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Sample records for boron-added low-carbon steels

  1. Microstructural and textural changes in a severely cold rolled boron-added interstitial-free steel

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    Saha, Rajib [Indian Institute of Technology, Kanpur 208 016 (India); R and D Division, Tata Steel, Jamshedpur (India)], E-mail: rajib.saha@tatasteel.com; Ray, R.K. [Indian Institute of Technology, Kanpur 208 016 (India); R and D Division, Tata Steel, Jamshedpur (India)

    2007-11-15

    The severe cold rolling of a single sheet of boron-added Ti + Nb IF steel at room temperature can produce nano- to ultrafine-sized grains. The number fraction of high-angle grain boundaries increases up to 98% cold rolling and then shows a perceptible decrease after further cold rolling. The coincidence site lattice (CSL) boundary fraction increases continuously with deformation. The most prominent among these CSL boundaries are the {sigma}3, {sigma}11 and {sigma}13b types.

  2. Aluminizing Low Carbon Steel at Lower Temperatures

    Institute of Scientific and Technical Information of China (English)

    Xiao Si; Bining Lu; Zhenbo Wang

    2009-01-01

    This study reports the significantly enhanced aluminizing behaviors of a low carbon steel at temperatures far below the austenitizing temperature, with a nanostructured surface layer produced by surface mechanical attrition treatment (SMAT). A much thicker iron aluminide compound layer with a much enhanced growth kinetics of η-Fe2Al5 in the SMAT sample has been observed relative to the coarse-grained steel sample. Compared to the coarse-grained sample, a weakened texture is formed in the aluminide layer in the SMAT sample. The aluminizing kinetics is analyzed in terms of promoted diffusivity and nucleation frequency in the nanostructured surface layer.

  3. Research of Mold Powder for Ultra-Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper explained the mechanism of carbon pickup byultra-low-carbon steels during continuous casting and indicated that the major cause of carbon pickup is the contact of the molten steel with the enriched-carbon layer of the powder. Forming of the enriched-carbon layer is due to the existing of “carbon core”. Accordingly, the measures to reduce the carbon content and amount of the enriched-carbon layer were investigated. A kind of new powder has been developed and successfully used to minimize the carbon pickup by ultra-low carbon steels during continuous casting.

  4. Control of nitrogen content in boron-added medium carbon steel%中碳含硼钢氮含量的控制

    Institute of Scientific and Technical Information of China (English)

    彭其春; 童志博; 陈立鹏; 杨柳; 彭明耀; 周春泉; 陈建新

    2013-01-01

    采用氧氮分析仪分析湖南华菱涟源钢铁集团有限公司中碳含硼钢A36-LB在生产各工序中氮含量的变化,研究其吸氮原因.结果表明,转炉终点碳含量控制不稳定是造成该厂钢中氮含量波动的主要因素;虽然转炉终点碳含量高可以降低钢中的氮含量,但同时也会导致钢中磷含量增高;在LF精炼整个过程中钢水增氮约11×10-6,增氮较多,其中原材料增氮并不是主要原因,主要原因是电弧加热过程增氮较为严重;连铸工艺段增氮较少,保护浇铸较好.%With oxygen and nitrogen analyzer, the change in nitrogen content in boron-added medium carbon steel produced by Valin Lianyuan Iron and Steel Corporation Limited in each stage of the process was analyzed and so was the nitrogen absorption mechanism. The results show that the insta-ble carbon content at BOF endpoint is the main factor for nitrogen content fluctuation. Though high carbon content at BOF endpoint may reduce the nitrogen content, it may lead to rephosphoration in BOF. Liquid steel nitrogen increase reaches 11×10-6 in LF refining process, which is rather significant. Yet the raw materials are not the main cause of nitrogen increase. Nitrogen increase mainly takes place during arc heating process. Nitrogen increase is comparatively small in CC process, which indicates protective casting is preferable.

  5. Austenite Recrystallization and Controlled Rolling of Low Carbon Steels

    Institute of Scientific and Technical Information of China (English)

    DU Lin-xiu; ZHANG Zhong-ping; SHE Guang-fu; LIU Xiang-hua; WANG Guo-dong

    2006-01-01

    The dynamic recrystallization and static recrystallization in a low carbon steel were investigated through single-pass and double-pass experiments. The results indicate that as the deformation temperature increases and the strain rate decreases, the shape of the stress-strain curve is changed from dynamic recovery shape to dynamic recrystallization shape. The austenite could not recrystallize within a few seconds after deformation at temperature below 900 ℃. According to the change in microstructure during deformation, the controlled rolling of low carbon steel can be divided into four stages: dynamic recrystallization, dynamic recovery, strain-induced ferrite transformation, and rolling in two-phase region. According to the microstructure after deformation, the controlled rolling of low carbon steel can be divided into five regions: non-recrystallized austenite, partly-recrystallized austenite, fully-recrystallized austenite, austenite to ferrite transformation, and dual phase.

  6. Twin structure of the lath martensite in low carbon steel

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    Pan Zhang

    2016-04-01

    Full Text Available It has been well accepted that the martensites in quenched carbon steels exhibit two typical morphologies which are closely dependent on the carbon content, i.e. lath martensite in low carbon steels and lenticular martensite in high carbon steels. Based on conventional belief, the lath martensites in low carbon steels are with high density dislocations as the substructure, in contrast to twin substructure in lenticular high carbon martensite. In the present work, an intensive transmission electron microscopy investigation was made to characterize the microstructures of the lath martensite in a low carbon steel of 0.2 wt%C. It was found that lots of lath martensites consist of twin as their substructure, rather than high density dislocations. In addition, nanoscale precipitates cohering with ferrite matrix were found at the twin interfaces. The orientation relationships between the precipitates and the ferrite matrix are in good agreement with that of primitive hexagonal ω phase in titanium alloys and other bcc metals or alloys.

  7. Twin structure of the lath martensite in low carbon steel

    Institute of Scientific and Technical Information of China (English)

    Pan Zhang; Yulin Chen; Wenlong Xiao; Dehai Ping; Xinqing Zhao

    2016-01-01

    It has been well accepted that the martensites in quenched carbon steels exhibit two typical morphol-ogies which are closely dependent on the carbon content, i.e. lath martensite in low carbon steels and lenticular martensite in high carbon steels. Based on conventional belief, the lath martensites in low carbon steels are with high density dislocations as the substructure, in contrast to twin substructure in lenticular high carbon martensite. In the present work, an intensive transmission electron microscopy investigation was made to characterize the microstructures of the lath martensite in a low carbon steel of 0.2 wt%C. It was found that lots of lath martensites consist of twin as their substructure, rather than high density dislocations. In addition, nanoscale precipitates cohering with ferrite matrix were found at the twin interfaces. The orientation relationships between the precipitates and the ferrite matrix are in good agreement with that of primitive hexagonalωphase in titanium alloys and other bcc metals or alloys.&2016 Chinese Materials Research Society. Production and hosting by Elsevier B.V. This is an open access.

  8. Oxidation of ultra low carbon and silicon bearing steels

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, Lucia [CTM - Technologic Centre, Materials Technology Area, Manresa, Barcelona (Spain)], E-mail: lucia.suarez@ctm.com.es; Rodriguez-Calvillo, Pablo [CTM - Technologic Centre, Materials Technology Area, Manresa, Barcelona (Spain)], E-mail: pablo.rodriguez@ctm.com.es; Houbaert, Yvan [Department of Materials Science and Engineering, University of Ghent (Belgium)], E-mail: Yvan.Houbaert@UGent.be; Colas, Rafael [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon (Mexico)], E-mail: rcolas@mail.uanl.mx

    2010-06-15

    Oxidation tests were carried out in samples from an ultra low carbon and two silicon bearing steels to determine the distribution and morphology of the oxide species present. The ultra low carbon steel was oxidized for short periods of time within a chamber designed to obtain thin oxide layers by controlling the atmosphere, and for longer times in an electric furnace; the silicon steels were reheated only in the electric furnace. The chamber was constructed to study the behaviour encountered during the short period of time between descaling and rolling in modern continuous mills. It was found that the oxide layers formed on the samples reheated in the electric furnace were made of different oxide species. The specimens treated in the chamber had layers made almost exclusively of wustite. Selected oxide samples were studied by scanning electron microscopy to obtain electron backscattered diffraction patterns, which were used to identify the oxide species in the layer.

  9. Ultrafine-grained low carbon steels by severe plastic deformation

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    S. Dobatkin

    2008-07-01

    Full Text Available The structure and properties of 0,14% C and 0,1% C - B low-carbon steels taken in two initial states, martensitic and ferritic-pearlitic, were studied after cold equal-channel angular (ECA pressing. ECA pressing leads to the formation of only partially submicrocrystalline structure with a grain size of 150 – 300 nm, depending on the steel alloying and initial state. The finest structure with the elements of 190 nm in size is obtained in the 0,1% C - B steel microalloyed with boron. The strength of the 0,1% C - B steel after cold ECA pressing (Rm = 805-1235 MPa meets the specifications of fasteners of the R80 - R120 strength grade. The strength of the deformed 0,14% C steel is close to the R80 strength grade.

  10. Elastic Sag Property of Low Carbon Martensite Spring Steel

    Institute of Scientific and Technical Information of China (English)

    LI Ye-sheng; CHEN Mi-song; WU Zi-ping; ZHU Yin-lu; DUO Tie-yun

    2004-01-01

    This paper studies the elastic sag resistance of new low-carbon martensite spring steel 35Si2CrVB developed recently and points out that the cause of elastic sag is attributed to cyclic softening of spring steel engendered during its serving,also considers that elastic sag property should be evaluated by dynamic mechanical properties of spring material such as dynamic yield strength σ'0.2, ratio of dynamic yield strength σ'0.2 vs. tensile strength σb (σ'0.2/σb) and ratio of dynamic yield strength σ' 0.2vs. static yield strengthσ0.2 (σ'0.2/σ0. 2 )etc. , which are measured by the cyclic stress-strain curve test. Compared with conventional spring steel 60Si2MnA, 35Si2CrVB has good advantages in both dynamic and static properties, which show it possesses higher elastic sag resistance than 60Si2MnA because of its lath-martensite structure tempering in low temperature different from 60Si2MnA steel's plate martensite structure tempering inmedium temperature. So it can be demonstrated that low carbon martensite spring steel is more appropriate for the demands of spring.

  11. Mechanical Properties and Corrosion Behavior of Low Carbon Steel Weldments

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    Mohamed Mahdy

    2013-01-01

    Full Text Available This research involves studying the mechanical properties and corrosion behavior of “low carbon steel” (0.077wt% C before and after welding using Arc, MIG and TIG welding. The mechanical properties include testing of microhardness, tensile strength, the results indicate that microhardness of TIG, MIG welding is more than arc welding, while tensile strength in arc welding more than TIG and MIG.The corrosion behavior of low carbon weldments was performed by potentiostat at scan rate 3mV.sec-1 in 3.5% NaCl to show the polarization resistance and calculate the corrosion rate from data of linear polarization by “Tafel extrapolation method”. The results indicate that the TIG welding increase the corrosion current density and anodic Tafel slop, while decrease the polarization resistance compared with unwelded low carbon steel. Cyclic polarization were measured to show resistance of specimens to pitting corrosion and to calculate the forward and reveres potentials. The results show shifting the forward, reverse and pitting potentials toward active direction for weldments samples compared with unwelded sample.

  12. Reduction of work hardening rate in low-carbon steels

    Science.gov (United States)

    Yalamanchili, Bhaskar Rao

    Low carbon grades of steel rods are used to produce finished products such as fine wire, coat hangers, staples, and roofing nails. These products are subject to ductility failures during production due to excessively high work hardening rates during wire drawing. The high work hardening rates are attributed to the presence of residuals, free nitrogen, or combinations thereof. This research concludes that the most cost-effective way to reduce the work hardening rate during wire drawing is to combine boron with nitrogen to form boron nitride, and thus reducing its work hardening contribution. The results of this study also conclude the following: (1) Boron/Nitrogen ratio is the more significant factor than rod tensile strength, which affects work hardening rate. Higher ratio is better in the 0.79 to 1.19 range. (2) Maintaining this narrow B/N range requires precise process control. (3) Process conditions such as dissolved oxygen (Steel Texas (North Star) benefited from this research by being able to provide a competitive edge in both quality and cost of its low carbon boron grades thus making North Star a preferred supplier of wire rod for these products.

  13. Deformation Behavior of Ultra-low Carbon Steel in Ferrite Region during Warm Processing

    Institute of Scientific and Technical Information of China (English)

    XU Guang; CHEN Zhenye; LIU Li; YU Shengfu

    2008-01-01

    The hot deformation experiments of ultra-low carbon steel in ferrite range were carried out ina hot simulator in order to research hot deformation behaviors of ultra-low carbon steel in ferrite range at low temperature.The results show that the influences of deformation parameters on flow stress are different to those in austenitic deformation.The deformation characteristic parameters were calculated for ultra-low carbon steel in ferrite region.The flow stress equation for ultra-low carbon steel in ferritic deformation at low temperature was obtained.

  14. FINITE DIFFERENCE SIMULATION OF LOW CARBON STEEL MANUAL ARC WELDING

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    Laith S Al-Khafagy

    2011-01-01

    Full Text Available This study discusses the evaluation and simulation of angular distortion in welding joints, and the ways of controlling and treating them, while welding plates of (low carbon steel type (A-283-Gr-C through using shielded metal arc welding. The value of this distortion is measured experimentally and the results are compared with the suggested finite difference method computer program. Time dependent temperature distributions are obtained using finite difference method. This distribution is used to obtain the shrinkage that causes the distortions accompanied with structural forces that act to modify these distortions. Results are compared with simple empirical models and experimental results. Different thickness of plates and welding parameters is manifested to illustrate its effect on angular distortions. Results revealed the more accurate results of finite difference method that match experimental results in comparison with empirical formulas. Welding parameters include number of passes, current, electrode type and geometry of the welding process.

  15. Electric arc surfacing on low carbon steel: Structure and properties

    Science.gov (United States)

    Ivanov, Yurii; Gromov, Victor; Kormyshev, Vasilii; Konovalov, Sergey; Kapralov, Evgenii; Semin, Alexander

    2016-11-01

    By the methods of modern materials science, the structure-phase state and microhardness distribution along the cross-section of single and double coatings surfaced on martensite low carbon steel by alloy powder-cored wire were studied. It was established that the increased mechanical properties of surfaced layer are determined by the sub-micro and nanodispersed martensite structure formation, containing iron borides forming the eutectic of lamellar form. The plates of Fe2B are formed mainly in the eutectic of a single-surfaced layer, while FeB is formed in a double-surfaced layer. The existence of bend extinction contours indicating the internal stress fields formation at the boundaries of Fe borides-α-Fe phases were revealed.

  16. Subgrains and boron distribution of low carbon bainitic steels

    Institute of Scientific and Technical Information of China (English)

    Xuemin Wang; Bing Cao; Chengjia Shang; Xueyi Liu; Xinlai He

    2005-01-01

    The structure variation of deformed austenite during the relaxation stage after deformation at various temperatures in an Nb-B ultra low carbon bainitic steel and Fe-Ni alloy was studied by the thermo-simulation. Optical microscope and TEM were applied to analyze the microstructure after RPC (Relaxation-precipitation-controlling phase transformation technique) and the evolution of dislocation configuration. The particle tracking autoradiography (PTA) technique, revealing the distribution of boron, was employed to show the change of boron segregation after different relaxation times. The results indicate that during the relaxation stage the recovery occurs in the deformed austenite, the dislocations rearrange and subgrains form. During the subsequent cooling the boron will segregate at the boundaries of subgrains.

  17. The structural dependence of work hardening in low carbon steels

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    Johnson, P.E.

    1991-12-01

    The influence of the dislocation cell structure on the work hardening behavior of low carbon steel sheets was investigated. Specimens were prestrained at low temperature to suppress cell formation and their subsequent behavior was compared with results of isothermal reference tests. It was found that the extent of cell development has little or no influence on the plastic behavior at room temperature and below. Interrupted temperature, tensile-shear tests demonstrated further that the transient behavior induced by loading path changes is also not strongly associated with the cell walls. In-situ straining studies indicate that the factor controlling the flow stress at room temperature is the limited mobility of screw dislocations moving the cell interiors, and not dislocation interactions with the cell walls. The unique properties of a/2<111> screw dislocations are known to dominate low temperature deformation behavior in bcc metals. The current work indicates that these dislocations may still control the flow stress at intermediate temperatures, even in the presence of a developed cell structure.

  18. Parameters Optimization of Low Carbon Low Alloy Steel Annealing Process

    Institute of Scientific and Technical Information of China (English)

    Maoyu ZHAO; Qianwang CHEN

    2013-01-01

    A suitable match of annealing process parameters is critical for obtaining the fine microstructure of material.Low carbon low alloy steel (20CrMnTi) was heated for various durations near Ac temperature to obtain fine pearlite and ferrite grains.Annealing temperature and time were used as independent variables,and material property data were acquired by orthogonal experiment design under intercritical process followed by subcritical annealing process (IPSAP).The weights of plasticity (hardness,yield strength,section shrinkage and elongation) of annealed material were calculated by analytic hierarchy process,and then the process parameters were optimized by the grey theory system.The results observed by SEM images show that microstructure of optimization annealing material are consisted of smaller lamellar pearlites (ferrite-cementite)and refining ferrites which distribute uniformly.Morphologies on tension fracture surface of optimized annealing material indicate that the numbers of dimple fracture show more finer toughness obviously comparing with other annealing materials.Moreover,the yield strength value of optimization annealing material decreases apparently by tensile test.Thus,the new optimized strategy is accurate and feasible.

  19. Optimization of fatigue damage indication in ferromagnetic low carbon steel

    Science.gov (United States)

    Tomáš, Ivan; Kovářík, Ondřej; Kadlecová, Jana; Vértesy, Gábor

    2015-09-01

    Fatigue damage was investigated by the method of magnetic adaptive testing (MAT), which is based on the systematic measurement and evaluation of minor magnetic hysteresis loops. A large number of magnetic measurements were performed on a single reference series of low carbon steel flat samples, which were fatigued by cyclic bending in an identical way, up to an increasing level of fatigue damage. The measurements of the magnetic properties of these samples were repeated under varied conditions, including speed of magnetization of the samples, sample temperature during the measurement, choice of the evaluated signal, frequency of the voltage sampling, and range of the applied amplitudes of the magnetizing field/current. Special attention was turned to the influence of the thickness of the non-ferromagnetic spacers positioned between the surface of the samples and the flat fronts of the attached magnetizing yokes. On one hand, the spacers decrease the values of the induced signal and its derivatives, but on the other hand they substantially increase the reproducibility of the measurement and positively influence the shapes of the resulting degradation curves. Optimum conditions for the magnetic measurement of the fatigue damage were searched, found, and recommended. The results indicate the reliable applicability of MAT to detect early stages of the material fatigue, and to predict its residual lifetime.

  20. Research on Welding Test of Grey Cast Iron and Low-Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Grey cast iron's welding itself is a complex proble m.So proper welding materials must be selected,complex welding techniques such as preheating before weldingslow cooling after welding etc,should be taken. However the carbon component in low-carbon steel is comparatively low,the carbo n of welded joint will diffuse to the low-carbon steel when it is welded with gr ey cast iron,which will cause the component of carbon greatly increased at the low-carbon steel side in HAZ,high carbon martensite and cracks ...

  1. Recent Progress in High Strength Low Carbon Steels

    Directory of Open Access Journals (Sweden)

    Zrník J.

    2006-01-01

    Full Text Available Advanced High Strength (AHS steels, among them especially Dual Phase (DP steels, Transformation Induced Plasticity (TRIP steels, Complex Phase (CP steels, Partially Martensite (PM steels, feature promising results in the field. Their extraordinary mechanical properties can be tailored and adjusted by alloying and processing. The introduction of steels with a microstructure consisting at least of two different components has led to the enlargement of the strength level without a deterioration of ductility. Furthermore, the development of ultra fine-grained AHS steels and their service performance are reviewed and new techniques are introduced. Various projects have been devoted to develop new materials for flat and long steel products for structural applications. The main stream line is High Strength, in order to match the weight lightening requirements that concern the whole class of load bearing structures and/or steel components and one of the most investigated topics is grain refinement.

  2. Solidification Structure of Low Carbon Steel Strips with Different Phosphorus Contents Produced by Strip Casting

    Institute of Scientific and Technical Information of China (English)

    Na LI; Zhenyu LIU; Yiqing QIU; Zhaosen LIN; Xianghua LIU; Guodong WANG

    2006-01-01

    In the present paper, low carbon steel strips with different phosphorus contents were produced using a twin roll strip casting process. The solidification structure was studied and its features were analyzed in detail. It was found that the strips possessed a fine microstructure compared with the mould cast steels. With increasing phosphorus content more ferrite has been formed with finer grains.

  3. CYCLIC RECRYSTALLIZATION OF FERRITE IN HOT-ROLLED LOW-CARBON SHEET STEEL WITH STRUCTURETEXTURAL HETEROGENEITY

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    A. M. Nesterenko

    2009-01-01

    Full Text Available It is determined that in the process of soaking at subcritical temperature 680 °C in hot-rolled rolling of low-carbon steel 08 ps recrystallization is developed with heterogeneous fu ll repeat change of the steel ferrite change by its section.

  4. Study on temper-rapid cooling process of low carbon steel produced by CSP

    Institute of Scientific and Technical Information of China (English)

    Huajie Wu; Yangchun Liu; Jie Fu

    2007-01-01

    On the basis of the effect of carbon precipitation on the microstructure and properties of steel products below A1 temperature,a new thermal treatment method (temper-rapid cooling process) was studied. By the temper-rapid cooling process, the yield strengths of the high strength low carbon (HSLC) steel ZJ330 and SPA-H produced using the compact strip production (CSP) process increased from 340 to about 410 MPa and from 410 to about 450 MPa, respectively. The results indirectly indicated that there existed nanoscaled iron-carbon precipitates that have obvious precipitation effect on low carbon steel produced by CSP. The prospect of application is discussed.

  5. New low-carbon steel for hot, warm, or cold forging

    Energy Technology Data Exchange (ETDEWEB)

    Ollilainen, V.; Hocksell, E. [Imatra Steel Oy Ab, Imatra Steelworks (Finland)

    2000-05-01

    The development of a new high-strength steel started from the needs of cold forging and continued into hot- and warm-forging areas. The steel has a very low carbon content (<0.1% C) and chromium-boron alloying. Its hardening is simple: just water quenching without tempering. Hot forgings of this steel are directly quenched from forging temperature, resulting in process cost savings and weight reduction. (orig.)

  6. Weldability of Low Carbon Transformation Induced Plasticity Steel

    Institute of Scientific and Technical Information of China (English)

    ZHANG Mei; LI Lin; FU Ren-yu; ZHANG Ji-cheng; WAN Zi

    2008-01-01

    Transformation induced plasticity (TRIP) steel exhibited high or rather high carbon equivalent (CE) because of its chemical composition,which was a particularly detrimental factor affecting weldability of steels.Thus the weldability of a TRIP steel (grade 600) containing (in mass percent,%) 0.11C-1.19Si-1.67Mn was extensively studied.The mechanical properties and impact toughness of butt joint,the welding crack susceptibility of weld and heat affected zone (HAZ) for tee joint,control thermal severity (CTS) of the welded joint,and Y shape 60° butt joint were measured after the gas metal arc welding (GMAW) test.The tensile strength of the weld was higher than 700 Mpa.Both in the fusion zone (FZ) and HAZ for butt joint,the impact toughness was much higher than 27 J,either at room temperature or at -20 ℃,indicating good low temperature impact ductility of the weld of TRIP 600 steel.In addition,welding crack susceptibility tests revealed that weldments were free of surface crack and other imperfection.All experimental results of this steel showed fairly good weldability.For application,the crossmember in automobile made of this steel exhibited excellent weldability,and fatigue and durability tests were also accomplished for crossmember assembly.

  7. Effect of Mo Content on Microstructure and Property of Low-Carbon Bainitic Steels

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    Haijiang Hu

    2016-07-01

    Full Text Available In this work, three low-carbon bainitic steels, with different Mo contents, were designed to investigate the effects of Mo addition on microstructure and mechanical properties. Two-step cooling, i.e., initial accelerated cooling and subsequent slow cooling, was used to obtain the desired bainite microstructure. The results show that the product of strength and elongation first increases and then shows no significant change with increasing Mo. Compared with Mo-free steel, bainite in the Mo-containing steel tends to have a lath-like morphology due to a decrease in the bainitic transformation temperature. More martensite transformation occurs with the increasing Mo, resulting in greater hardness of the steel. Both the strength and elongation of the steel can be enhanced by Mo addition; however, the elongation may decrease with a further increase in Mo. From a practical viewpoint, the content of Mo could be ~0.14 wt. % for the composition design of low-carbon bainitic steels in the present work. To be noted, an optimal scheme may need to consider other situations such as the role of sheet thickness, toughness behavior and so on, which could require changes in the chemistry. Nevertheless, these results provide a reference for the composition design and processing method of low-carbon bainitic steels.

  8. Prediction of Hot Ductility of Low-Carbon Steels Based on BP Network

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The purpose of the research is to obtain an effective method to predict the hot ductility of low-carbon steels, which will be a re ference to evaluate the crack sensitivity of steels. Several sub-netwo rks modeled from BP network were constructed for different temperature use, and the measured reduction of area (AR) of 12 kinds of low-carbo n steels under the temperature of 600 to 1000℃ were processed as trai ning samples. The result of software simulation shows that the model e stablished is relatively effective for predicting the hot ductility of steels.

  9. About Reverted Austenite in Carburized Layers of Low-Carbon Martensitic Steels

    Science.gov (United States)

    Ivanov, A. S.; Bogdanova, M. V.; Vylezhnev, V. P.

    2015-05-01

    Processes of surface hardening in low-carbon martensitic steel 24Kh2G2NMFTB under carburizing and subsequent quenching from the intercritical temperature range are studied. Special features of formation of reverted austenite with high strength and stability are considered.

  10. DEFORMATION AND FRACTURE MICROPROCESSES OF EXPLOSIVELY LOADED LOW-CARBON STEELS UNDER TENSION

    OpenAIRE

    Larionov, V; Yakovleva, S.

    1991-01-01

    The mechanism of strength properties formation in low-carbon steels subjected to explosive treatment is investigated. With this aim in view, the features inherent to plastic deformation and fracture microprocesses have been studied. A quantitative analysis of the microinhomogeneous plastic deformation characteristics has been carried out.

  11. Effects of tantalum content on the microstructure and mechanical properties of low-carbon RAFM steel

    Science.gov (United States)

    Chen, Jianguo; Liu, Chenxi; Liu, Yongchang; Yan, Biyu; Li, Huijun

    2016-10-01

    In order to explore the influence of tantalum content on the microstructure and mechanical properties of low carbon RAFM (reduced activation ferritic/martensitic) steels, three low carbon RAFM steels with different tantalum contents (0%, 0.027%, 0.073%) were designed. The precipitation behavior and effect of precipitates on the mechanical properties of the Low-C RAFM steel were investigated. The results indicate that increase of tantalum content causes decrease of the prior austenite grain size and the amount of M23C6 carbides precipitated along prior austenite grain boundaries and packet boundaries as well as increase of the amount of MX nano-sized particles within intragranular regions. The impact properties of low carbon RAFM steels are excellent regardless of the tantalum content. The impact properties and hardness are obviously improved by increasing tantalum content, which may be related to increase of the number of MX and decrease of M23C6. Furthermore, the tensile properties at elevated temperature below 600 °C are hardly changed with increase of tantalum content, yet those at 800 °C are improved with increasing tantalum content. This implies that MX carbides would be more important for tensile properties at higher temperature.

  12. Modeling of mechanical behaviour of HSLA low carbon bainitic steel thermomechanically processed

    Science.gov (United States)

    Santos, D. B.; Rodrigues, P. C. M.; Cota, A. B.

    2003-10-01

    A comparative study of the microstructure characterization and mechanical properties was done in a HSLA low carbon (0.08%) bainitic steel containing boron, developed by industry as a bainitic steel grade APIX80. The steel was submitted to two different thermomechanical processes. In the first one, controlled rolling followed by accelerated cooling was applied in laboratory mill. In the second processing, specimens of the same steel were submitted to hot torsion testing. The influence of cooling conditions like start cooling temperature, cooling rates and finish cooling temperature on the microstructure and mechanical properties were investigated. The final microstructure obtained was a complex mixture of polygonal ferrite, perlite, bainite and martensite/retained austenite constituent. The use of multiple regression analysis allowed the establishment of quantitative relationships between the accelerated cooling variables and mechanical properties of the steel available from Vickers microhardness and tensile tests.

  13. Microstructure and Mechanical Properties of Resistance Spot Welding Joints of Carbonitrided Low-Carbon Steels

    Science.gov (United States)

    Taweejun, Nipon; Poapongsakorn, Piyamon; Kanchanomai, Chaosuan

    2017-04-01

    Carbonitrided low-carbon steels are resistance welded in various engineering components. However, there are no reports on the microstructure and mechanical properties of their resistance spot welding (RSW) joints. Therefore, various carbonitridings were performed on the low-carbon steel sheets, and then various RSWs were applied to these carbonitrided sheets. The metallurgical and mechanical properties of the welding joint were investigated and discussed. The peak load and failure energy increased with the increases of welding current and fusion zone (FZ) size. At 11 kA welding current, the carbonitrided steel joint had the failure energy of 16 J, i.e., approximately 84 pct of untreated steel joint. FZ of carbonitrided steel joint consisted of ferrite, Widmanstatten ferrite, and untempered martensite, i.e., the solid-state transformation products, while the microstructure at the outer surfaces consisted of untempered martensite and retained austenite. The surface hardening of carbonitrided steel after RSW could be maintained, i.e., approximately 810 HV. The results can be applied to carbonitriding and RSW to achieve a good welding joint.

  14. Improved Wear Resistance of Low Carbon Steel with Plasma Melt Injection of WC Particles

    Science.gov (United States)

    Liu, Aiguo; Guo, Mianhuan; Hu, Hailong

    2010-08-01

    Surface of a low carbon steel Q235 substrate was melted by a plasma torch, and tungsten carbide (WC) particles were injected into the melt pool. WC reinforced surface metal matrix composite (MMC) was synthesized. Dry sliding wear behavior of the surface MMC was studied and compared with the substrate. The results show that dry sliding wear resistance of low carbon steel can be greatly improved by plasma melt injection of WC particles. Hardness of the surface MMC is much higher than that of the substrate. The high hardness lowers the adhesion and abrasion of the surface MMC, and also the friction coefficient of it. The oxides formed in the sliding process also help to lower the friction coefficient. In this way, the dry sliding wear resistance of the surface MMC is greatly improved.

  15. Effect of hydrogen attack on acoustic emission behavior of low carbon steel

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In order to investigate the effect of hydrogen attack degree on acoustic emission (AE) behavior of low carbon steel during tensiling, specimens made of low carbon steel was exposed to hydrogen gas of 18 MPa at 450 and 500℃ for 240, 480 and 720 h respectively. Experimental results show that with increase of the hydrogen attack degree, the totally AE activity decreases during tensiling. In addition, the count of AE signals with high amplitude for the specimens with hydrogen attack keeps a constant which is less than that without hydrogen attack. It is concluded that AE signals originate in the specimens with hydrogen attack from intergranular fracture induced by methane blisterings or/and microcracks on grain boundaries.

  16. Contribution of electrochemical dissolution during pickling of low carbon steel in acidic solutions

    OpenAIRE

    2014-01-01

    International audience; An electrochemical cell coupled with ICP-OES chemical analysis was used to explore the role of chemical and electrochemical reactions in pickling of low carbon steel in acidic media. Impedance spectroscopy was used to highlight scale properties. Dissolution of hematite is shown to be mainly of chemical nature, whereas the dissolution of magnetite and wüstite is both chemical and electrochemical. Initially, chemical dissolution of the scale dominated. The electrochemica...

  17. Use of Artificial Neural Network for Predicting the Mechanical Property of Low Carbon Steel

    OpenAIRE

    Somkuwar, Vandana

    2013-01-01

    For product development manufacturers and designers need information about the existing materials and new material and its properties as early as possible. This paper presents a method of predicting the properties of unknown material using artificial neural network. The developed neural network model is employed for simulations of the relationship between mechanical property and the chemical composition of low carbon steel. Simulating and analyzing result shows that network model can effectiv...

  18. Kinetics of austenite formation during continuous heating in a low carbon steel

    OpenAIRE

    Oliveira, Fernando Lucas Gonçalves e; Andrade, Margareth Spangler; Cota, André Barros

    2007-01-01

    The kinetics and microstructural evolution of austenite formation in a low carbon steel, with initial microstructure composed of ferrite and pearlite, were studied during continuous heating, by using dilatometric analysis and measurements of microstructural parameters. The formation of austenite was observed to occur in two stages: (a) pearlite dissolution and (b) ferrite to austenite transformation. The critical temperatures of austenite formation in continuous heating increase with increasi...

  19. EFFECT OF ELECTRIC FIELD ON THE AUSTENIZATION OF A LOW CARBON STEEL

    Institute of Scientific and Technical Information of China (English)

    X.T.Liu; J.Z.Cui

    2004-01-01

    With an electric field during austenitizing, the martensite transformation of the low carbon steel was promoted, and more martensite were obtained. The electric field promotes the homogeneity of carbon, and reduces the free energy of austenite. The critical neuclus r* and the critical driving force G* responsible for the nucleation of proeutectoid ferrite were increased. As a result of which the diffusion controlled proeuctoid ferrite transformation was retarded and the hardenability was improved.

  20. Computer Simulation of Ferrite Transformation during Hot Working of Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    Yunbo XU; Yongmei YU; Xianghua LIU; Guodong WANG

    2004-01-01

    On the basis of transformation kinetics and thermodynamics, the austenite-ferrite transformation start temperature during deformation was predicted for several grades of low-carbon steels under different processing conditions. Results indicate that Ar3d temperature mostly depended on alloying composition and processing parameters. Ar3d increased as strain rate or strain increased for the same steel grade. In view of enhancement of deformation on transformation,the basic kinetics model was established to simulate deformation induced transformation behavior, using which the influence of the deformation stored energy and effective deformation ledge on the nucleation and growth can be considered. The simulated results are in good agreement with experiment results.

  1. Dynamic Recrystallization and Grain Growth Behavior of 20SiMn Low Carbon Alloy Steel

    Institute of Scientific and Technical Information of China (English)

    DONG Lanfeng; ZHONG Yuexian; MA Qingxian; YUAN Chaolong; MA Lishen

    2008-01-01

    A senes of thermodynamics experiments were used to optimize the hot forging process of 20SiMn low-carbon alloy steel.A dynamic recrystallization and grain growth model was developed for the 20SiMn steel for common production conditions of heavy forgings by doing a nonlinear curve fit of the expenment data.Optimized forging parameters were developed based on the control of the dynamic recrystallization and the MnS secondary phase.The data shows that the initial grain size and the MnS secondary phase all affect the behavior of the 20SiMn dynamic recrystallization and grain growth.

  2. MODELING OF FERRITE GRAIN GROWTH OF LOW CARBON STEELS DURING HOT ROLLING

    Institute of Scientific and Technical Information of China (English)

    Y.T. Zhang; D.Z. Li; Y.Y. Li

    2002-01-01

    For most commercial steels the prediction of the final properties depends on accuratelycalculating the room temperature ferrite grain size. A grain growth model is proposedfor low carbon steels Q235B during hot rolling. By using this model, the initial ferritegrain size after continuous cooling and ferrite grain growing in coiling procedure canbe predicted. Finally, in-plant trials were performed in the hot strip mill of Ansteel.The calculated final ferrite grain sizes are in good agreement with the experimentalones. It is helpful both for simulation of microstructure evolution and prediction ofmechanical properties.

  3. Mathematical modeling and validation of the carburizing of low carbon steels

    Science.gov (United States)

    García Mariaca, A.; Cendales, E. D.; Chamarraví, O.

    2016-02-01

    This paper shows the mathematical modeling of heat and mass transfer in transient state of cylindrical bars of low carbon steel subjected to carburizing process. The model solution for the two phenomena was performed using a one-dimensional analysis in the radius direction, using the numerical method of finite differences; also a sensitivity analysis by varying the coefficient of convective heat transfer (h) is performed. The modeling results show that this carburization steel is strongly dependent on h. These results suggest that if it can increase the value of h in this kind of process could reduce the time of process for this heat treatment. Additionally, an experimental procedure was established by carburization of a steel AISI SAE 1010, which develops cementing solid phase and the specimen steel and micrographic hardness profiles obtained from samples of the specimen analysis was performed, to determine the penetration depth of the carbon and validate this result over the values obtained by the computer model.

  4. Influence of Molybdenum Addition on Mechanical Properties of Low Carbon HSLA-100 Steel

    Directory of Open Access Journals (Sweden)

    Bogucki R.

    2014-10-01

    Full Text Available The results of mechanical properties and microstructure observation of low carbon copper bearing steel with high addition of molybdenum are presented in this paper. This steels were characterized by contents of molybdenum in the range from 1% to 3% wt. After the thermo -mechanical processing the steels were subsequently quenched and tempered at different temperatures (500-800 °C for 1h. The changes of mechanical properties as function of tempering temperature were typical for the steel with the copper addition. The sudden drop of impact resistance after tempering from 575 °C to 600 °C was caused probably by precipitates of Laves phase of type Fe2Mo.

  5. The influence of molybdenum on stress corrosion in Ultra Low Carbon Steels with copper addition

    Directory of Open Access Journals (Sweden)

    M. Mazur

    2010-07-01

    Full Text Available The influence of molybdenum content on the process of stress corrosion of ultra-low carbon structural steels with the addition of copper HSLA (High Strength Low Alloy was analyzed. The study was conducted for steels after heat treatment consisting of quenching andfollowing tempering at 600°C and it was obtained microstructure of the tempered martensite laths with copper precipitates and the phaseLaves Fe2Mo type. It was found strong influence of Laves phase precipitate on the grain boundaries of retained austenite on rate anddevelopment of stress corrosion processes. The lowest corrosion resistance was obtained for W3 steel characterized by high contents ofmolybdenum (2.94% Mo which should be connected with the intensity precipitate processes of Fe2Mo phase. For steels W1 and W2which contents molybdenum equals 1.02% and 1.88%, respectively were obtained similar courses of corrosive cracking.

  6. Mechanical and service properties of low carbon steels processed by severe plastic deformation

    Directory of Open Access Journals (Sweden)

    J. Zrnik

    2009-07-01

    Full Text Available The structure and properties of the 0,09% C-Mn-Si-Nb-V-Ti, 0,1% C-Mn-V-Ti and 0,09% C-Mo-V-Nb low-carbon steels were studied after cold equal-channel angular pressing (ECAP. ECAP leads to the formation of partially submicrocrystalline structure with a grain size of 150 – 300 nm. The submicrocrystalline 0,09% C-Mn-Si-Nb-V-Ti steel compared with the normalized steel is characterized by Re higher more than by a factor of 2 and by the impact toughness higher by a factor of 3,5 at a test temperature of -40°C. The plasticity in this case is somewhat lower. The high-strength state of the submicrocrystalline 0,1% C-Mn-V-Ti and 0,09% C-Mo-V-Nb steels after ECAP is retained up to a test temperature of 500°C. The strength properties at 600°C (i.e. the fire resistance of these steels are higher by 20-25% as compared to those of the undeformed steels. The strength of the 0,09% C-Mo-V-Nb steel at 600°C is substantially higher than that of the 0,1% C-Mn-V-Ti steel.

  7. Formation of carburized layer structure with reverted austenite on low-carbon martensitic steel 12Kh2G2NMFT

    Science.gov (United States)

    Ivanov, A. S.; Bogdanova, M. V.

    2013-03-01

    The structure of surface layer in low-carbon martensitic steel 12Kh2G2NMFT obtained by carburizing followed by high-temperature tempering and quenching from the intercritical temperature range is investigated.

  8. Hot ductility behavior of a low carbon advanced high strength steel (AHSS) microalloyed with boron

    Energy Technology Data Exchange (ETDEWEB)

    Mejia, I., E-mail: imejia@umich.mx [Instituto de Investigaciones Metalurgicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio ' U' , Ciudad Universitaria, 58066 Morelia, Michoacan (Mexico); Bedolla-Jacuinde, A.; Maldonado, C. [Instituto de Investigaciones Metalurgicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio ' U' , Ciudad Universitaria, 58066 Morelia, Michoacan (Mexico); Cabrera, J.M. [Departament de Ciencia dels Materials i Enginyeria Metal.lurgica, ETSEIB - Universitat Politecnica de Catalunya, Av. Diagonal 647, 08028 Barcelona (Spain); Fundacio CTM Centre Tecnologic, Av. de las Bases de Manresa 1, 08240 Manresa (Spain)

    2011-05-25

    Research highlights: {yields} Effect of boron on the hot ductility behavior of a low carbon NiCrVCu AHSS. {yields} Boron addition of 117 ppm improves hot ductility over 100% in terms of RA. {yields} Hot ductility improvement is associated with segregation/precipitation of boron. {yields} Typical hot ductility recovery at lower temperatures does not appear in this steel. {yields} Hot ductility loss is associated with precipitates/inclusions coupled with voids. - Abstract: The current study analyses the influence of boron addition on the hot ductility of a low carbon advanced high strength NiCrVCu steel. For this purpose hot tensile tests were carried out at different temperatures (650, 750, 800, 900 and 1000 deg. C) at a constant true strain rate of 0.001 s{sup -1}. Experimental results showed a substantial improvement in hot ductility for the low carbon advanced high strength steel when microalloyed with boron compared with that without boron addition. Nevertheless, both steels showed poor ductility when tested at the lowest temperatures (650, 750 and 800 deg. C), and such behavior is associated to the precipitation of vanadium carbides/nitrides and inclusions, particularly MnS and CuS particles. The fracture mode of the low carbon advanced high strength steel microalloyed with boron seems to be more ductile than the steel without boron addition. Furthermore, the fracture surfaces of specimens tested at temperatures showing the highest ductility (900 and 1000 deg. C) indicate that the fracture mode is a result of ductile failure, while in the region of poor ductility the fracture mode is of the ductile-brittle type failure. It was shown that precipitates and/or inclusions coupled with voids play a meaningful role on the crack nucleation mechanism which in turn causes a hot ductility loss. Likewise, dynamic recrystallization (DRX) which always results in restoration of ductility only occurs in the range from 900 to 1000 deg. C. Results are discussed in terms of

  9. Effect of boron on hot strips of low carbon steel produced by compact strip production

    Institute of Scientific and Technical Information of China (English)

    Hao Yu; Yonglin Kang

    2008-01-01

    The effect of boron on hot strips of low carbon steel produced by compact strip production (CSP) to reduce the strength to a certain degree was investigated, which is quite different from that of high-strength low alloy steel. The mechanical properties and microstructural evolution of the hot strip were studied using optical microscopy and tensile tests. By means of an electrolytic disso- lution technique and Thermo-Cal calculation, the precipitates containing boron were analyzed and detected. From the electron back- scattered diffraction analysis, it can be deciphered whether the microstructure has recrystallized or not. Furthermore, the effect of boron segregation on the recrystallization or non-recrystallization conditions can be distinguished. The segregation behavior of boron was investigated in boron-containing steel. The nonequilibrium segregation of boron during processing was discussed on the basis of the forming complexes with vacancies that migrate to the boundaries prior to annihilation, which was confirmed by the subsequent cold rolling with annealing experiments.

  10. Joining of Low-Carbon Steel Sheets with Al-Based Weld

    Directory of Open Access Journals (Sweden)

    Boczkal G.

    2016-03-01

    Full Text Available The analysis of the connection steel/Al/steel made by resistance welding was performed. The used low-carbon steel had low content of carbon and other elements, aluminum was of 99.997 wt.% Al purity. Formation of various FeAl intermetallic phases found in the phase diagram depending on the duration of the process was analyzed. Two distinctively different types of structure depending on time of welding were observed: 1 hypoeutectic structure for samples processed for 5 s, and 2 eutectic structure for samples processed for 10 s and more. The shear test showed increase of mechanical properties of the connection for the samples welded 10 s.

  11. Corrosion protection of low-carbon steel using exopolysaccharide coatings from Leuconostoc mesenteroides.

    Science.gov (United States)

    Finkenstadt, Victoria L; Côté, Gregory L; Willett, J L

    2011-06-01

    Corrosion of metals is a serious and challenging problem faced worldwide by industry. Purified Leuconostoc mesenteroides exopolysaccharide (EPS) coatings, cast from aqueous solution, inhibited the corrosion of low-carbon steel as determined by electrochemical impedance spectroscopy (EIS). There were two different corrosion behaviors exhibited when EPS films from different strains were cast onto the steel. One EPS coating reacted immediately with the steel substrate to form an iron (III) oxide layer ("rust") during the drying process while another did not. The samples that did not flash corrode had higher corrosion inhibition and formed an iron (II) passivation layer during EIS testing that persisted after the cells were disassembled. Corrosion inhibition was strain-specific as polysaccharides with similar structure did not have the same corrosion potential.

  12. Processing of low carbon steel plate and hot strip—An overview

    Indian Academy of Sciences (India)

    B K Panigrahi

    2001-08-01

    Soaking temperature, drafting schedule, finish rolling and coiling temperatures all play important roles in processing of low carbon plate and strip. They control the kinetics of various physical and metallurgical processes, viz. austenitization, recrystallization and precipitation behaviour. The final transformed microstructures depend upon these processes and their interaction with each other. In view of increasing cost of input materials, new processing techniques such as recrystallized controlled rolling and warm rolling have been developed for production of plates and thinner hot bands with very good deep drawability respectively. Besides hybrid computer modelling is used for production of strip products with tailor made properties. Although there have been few reviews on low carbon microalloyed steels in the past the present one deals with new developments.

  13. Thermodynamic Research on Precipitates in Low Carbon Nb-Microalloyed Steels Produced by Compact Strip Production

    Institute of Scientific and Technical Information of China (English)

    Song XIANG; Guoquan LIU; Yang LI; Changrong LI; Andong WANG

    2007-01-01

    Microalloying element Nb in low carbon steels produced by compact strip production (CSP) process plays an important role in inhibiting recrystallization, decreasing the transformation temperature and grain refinement.With decreasing the rolling temperature, dislocations can be pinned by carbonitrides and the strength is increased. Based on the two sublattice model, with metal atom sublattice and interstitial atom sublattice,a thermodynamic model for carbonitride was established to calculate the equilibrium between matrix and carbonitride. In the steel produced by CSP, the calculation results showed that the starting temperature of precipitation of Ti and Nb are 1340℃ and 1040℃, respectively. In the range of 890-950℃, Nb rapidly precipitated. And the maximum of the atomic fraction of Nb in carbonitride was about 0.68. The morphologies and energy spectrum of the precipitates showed that (NbTi) (CN) precipitated near the dislocations. The experiment results show that Nb rapidly precipitated when the temperature was lower than 970℃, and the atomic fraction of Nb in carbonitride was about 60%-80%. The calculation results are in agreement with the experiment data. Therefore the thermodynamic model can be a useful assistant tool in the research on the precipitates in the low carbon steels produced by CSP.

  14. STUDY OF DYNAMIC RECRYSTALLIZATION OF LOW CARBON STEEL IN THIN SLAB CONTINUOUS ROLLING PROCESS

    Institute of Scientific and Technical Information of China (English)

    X.K. Liang; X.J. Sun; Q.Y. Liu; H. Dong

    2006-01-01

    Combined with the technological characteristics of thin slab continuous rolling process (TSCR),dynamic recrystallization of an extremely coarse austenite of low carbon steel is studied by Thermecmaster-Z hot simulator. By the analysis of true stress-strain curves and the observation of microstructures at different deformation stages, the critical stress and critical strain are determined under different deformation conditions. The effect of Z parameter on dynamic recrystallization of coarse austenite is studied. The microstructure evolution in real production is also discussed.

  15. Effect of quenching techniques on the mechanical properties of low carbon structural steel

    Directory of Open Access Journals (Sweden)

    K. Miernik

    2010-07-01

    Full Text Available The paper presents the results of the impact of incomplete quenching technique on the mechanical properties of low carbon structural steel.Significant influence of the heating method to the α + γ field was observed on the strength and plasticity after hardening process. The best combination of mechanical properties was obtained for the 3th technique consisting of pre-heating the material to the austenite field, next cooling to the appropriate temperature in the α + γ and hardening from that dual phase region. The high level of toughness with relatively high strength were observed, compared to the properties obtained for the two other ways to quench annealing (incomplete hardening.

  16. Scale formation and descaling in hot rolling of low carbon steel

    Science.gov (United States)

    Basabe Mancheno, Vladimir Vinicio

    In this research, the effects of gas composition, elapsed time of reaction and temperature on scale formation and descaling of low carbon steel were investigated and results were discussed from the viewpoint of the phase composition of the scales, oxidation rates, oxidation mechanisms, adhesion, fracture mechanics, porosity and residual scale. The phase composition and morphology of scales grown under conditions similar to those of reheating furnaces were analyzed. Low carbon steel was oxidized over the temperature range 1000-1250°C in gas mixtures of O 2-CO2-H2O-N2, O2-H 2O-N2 and O2-CO2-N2. The mole fraction of each phase, wustite (FeO), magnetite (Fe3O 4) and hematite (Fe2O3) was determined by the direct comparison method Two types of scales were observed. The first type was a crystalline scale with an irregular outer surface composed mostly of wustite, and a negligible amount of magnetite. The second type was the classical three-layer scale composed of wustite, magnetite and hematite. In general, the experiments showed that the furnace atmosphere, oxidation time and temperature influence the phase composition of the scales. Low carbon steel was oxidized in air over the temperature range 600-1200°C for 120 s to approximate the formation of secondary and tertiary scale in hot rolling. The mole fraction of wustite, magnetite and hematite was determined by the direct comparison method The phase composition of the scales changed with temperature and time. During the initial 30 s of oxidation, wustite was the predominant phase in the temperature range 800-1200°C, and as oxidation proceeded, the percentages of magnetite and hematite increased. In addition, the texture of the scales was investigated by orientation imaging microscopy (OIM); it was found that temperature influences the texture of the scales. The experiments indicated that 850°C is the ideal temperature for the finishing mill in order to reduce surface defects and work roll wear. The adhesion of

  17. Advanced manufacturing technologies of large martensitic stainless steel castings with ultra low carbon and high cleanliness

    Directory of Open Access Journals (Sweden)

    Lou Yanchun

    2010-11-01

    Full Text Available The key manufacturing technologies associated with composition, microstructure, mechanical properties, casting quality and key process control for large martensitic stainless steel castings are involved in this paper. The achievements fully satisfied the technical requirements of the large 700 MW stainless steel hydraulic turbine runner for the Three Gorges Hydropower Station, and become the major technical support for the design and manufacture of the largest 700 MW hydraulic turbine generator unit in the world developed through our own efforts. The characteristics of a new high yield to tensile strength (Rp0.2/Rm ratio and high obdurability martensitic stainless steel with ultra low carbon and high cleanliness are also described. Over the next ten years, the large martensitic stainless steel castings and advanced manufacturing technologies will see a huge demand in clean energy industry such as nuclear power, hydraulic power at home and abroad. Therefore, the new high yield o tensile strength (Rp0.2/Rm ratio and high obdurability martensitic stainless steel materials, the fast and flexible manufacturing technologies of large size castings, and new environment friendly sustainable process will face new challenges and opportunities.

  18. Tailoring the gradient ultrafine-grained structure in low-carbon steel during drawing with shear

    Directory of Open Access Journals (Sweden)

    G. I. Raab

    2016-04-01

    Full Text Available Conventional drawing and drawing with shear were conducted on the rods of low-carbon steel. Deformation by simple drawing forms basically a homogenous structure and leads to a uniform change in microhardness along the billet volume. A comparative analysis of the models of these processes showed that shear drawing of steel at room temperature reduces energy characteristics in half, normal forces on the die – by 1,8, and enhances the strain intensity from 0,5 to 1,6. During drawing with shear, strain-induced cementite dissolution occurs and a gradient structure is formed, which increases the microhardness of the surface layer up to values close to 7 000 MPa.

  19. Modeling of Reversible γ/α Transformations of Low Carbon Steels in the Intercritical Temperature Range

    Institute of Scientific and Technical Information of China (English)

    Tam(a)s R(E)TI; Imre FELDE; Hakan G(U)R

    2004-01-01

    A phenomenological kinetic model has been developed for the prediction of non-isothermal reversible incomplete transformations in low-carbon hypoeutectoid steels. The theoretical basis of the proposed method has its origin in a possible extension of the traditional Austin-Rickett kinetic differential equation. To critically assess the applicability of the model, anumber of experiments based on computer simulations have been performed to predict the austenite/ferrite proeutectoid transformation in the temperature range of Ae1 to Ae3 on plain carbon hypoeutectoid steels. A comparison with published experimental data has verified that the model developed is reasonable both quantitatively and with respect to well-established trends. Extension of the method of prediction appears promising when the non-isothermal reactions occurring during heat treatment (such as carbide precipitation and dissolution) can be assumed to proceed in a reversible manner.

  20. Effect of silicon and prior deformation of austenite on isothermal transformation in low carbon steels

    Institute of Scientific and Technical Information of China (English)

    Minghui CAI; Hun DING; Jiansu ZHANG; Long LI

    2009-01-01

    Isothermal transformation (TTT) behavior of the low carbon steels with two Si con-tents (0.50 wt pct and 1.35 wt pct) was investigated with and without the prior deformation. The results show that Si and the prior deformation of the austenite have significant effects on the transformation of the ferrite and bainite. The addition of Si refines the ferrite grains, accelerates the polygonal ferrite transformation and the formation of M/A constituents, leading to the improvement of the strength. The ferrite grains formed under the prior deformation of the austenite become more ho-mogeneous and refined. However, the influence of deformation on the tensile strength of both steels is dependent on the isothermal temperatures. Thermodynamic calcu-lation indicates that Si and prior deformation reduce the incubation time of both ferrite and bainite transformation, but the effect is weakened by the decrease of the isothermal temperatures.

  1. Mathematical Modeling and Microstructure Analysis of Low Carbon Steel Strips Produced by Horizontal Single Belt Casting (HSBC)

    Science.gov (United States)

    Ge, Sa; Chang, Sheng; Wang, Tong; Calzado, Luis E.; Isac, Mihaiela; Kozinski, Janusz; Guthrie, Roderick I. L.

    2016-06-01

    The horizontal single belt casting (HSBC) process has been proposed as an efficient, economical, and environmentally friendly alternative approach to the production of ferrous alloys. Low carbon steel strips were cast using the HSBC simulator apparatus to study the characteristics and properties of the as-cast steel strips. Three-dimensional computational fluid dynamics simulations using ANSYS FLUENT 14.5 were also performed. Numerical predictions were validated against experimental casting results. Microstructural analyses and as-cast surface texture studies were conducted on low carbon steels.

  2. Effect of Niobium and Titanium on Dynamic Recrystallization Behavior of Low Carbon Steels

    Institute of Scientific and Technical Information of China (English)

    MA Li-qiang; LIU Zhen-yu; JIAO Si-hai; YUAN Xiang-qian; WU Di

    2008-01-01

    Using a Gleeble 3800 thermo-mechanical simulator, the effect of niobium and titanium on the dynamic re-crystallization (DRX) behavior of low carbon steels was investigated. Isothermal single compression tests were per-formed in the temperature range of 850 to 1 150 ℃ at eonatant strain rates of 0. 1 to 5 s-1. The experimental results showed that the addition of niobium and titanium to the low carbon steels significantly increased both the peak stress and steady state stress. The activation energy of deformation Qd was larger than the activation energy associated with the steady state stress Qss. Furthermore, the difference between Qd and Qss became significant because of the addition of niobium and titanium. DRX is effeetively retarded beeause of solute dragging and dynamic precipitate pinning of niobium and titanium, resulting in higher values of the peak strain and steady state strain. Finally, the influence of niobium and titanium on the DRX kinetics and steady state grain size was determined.

  3. Effect of temper rolling on the bake-hardening behavior of low carbon steel

    Institute of Scientific and Technical Information of China (English)

    Chun-fu Kuang; Shen-gen Zhang; Jun Li; Jian Wang; Pei Li

    2015-01-01

    In a typical process, low carbon steel was annealed at two different temperatures (660°C and 750°C), and then was temper rolled to improve the mechanical properties. Pre-straining and baking treatments were subsequently carried out to measure the bake-hardening (BH) values. The influences of annealing temperature and temper rolling on the BH behavior of the steel were investigated. The results indicated that the microstructure evolution during temper rolling was related to carbon atoms and dislocations. After an apparent increase, the BH value of the steel significantly decreased when the temper rolling reduction was increased from 0%to 5%. This was attributed to the increase in solute carbon concentration and dislocation density. The maximum BH values of the steel annealed at 660°C and 750°C were 80 MPa and 89 MPa at the reductions of 3%and 4%, respectively. Moreover, increasing the annealing temperature from 660 to 750°C resulted in an ob-vious increase in the BH value due to carbide dissolution.

  4. Effects of Rolling and Cooling Conditions on Microstructure and Mechanical Properties of Low Carbon Cold Heading Steel

    Institute of Scientific and Technical Information of China (English)

    LI Zhuang; WU Di; LV Wei

    2012-01-01

    Effects of rolling and cooling conditions on microstructure and mechanical properties of low carbon cold heading steel were investigated on a laboratory hot rolling mill. The results have shown that the mechanical proper ties of low carbon steels exceed the standard requirements of ML30, ML35, ML40, and ML45 steel, respectively due to thermomechanical controlled processing (TMCP). This is attributed to a significant amount of pearlite and the ferrite-grain refinement. Under the condition of relatively low temperature rolling, the mechanical properties exceed standard requirements of ML45 and ML30 steel after water cooling and air cooling, respectively. Fast cooling which leads to more pearlite and finer ferrite grains is more critical than finish rolling temperatures for low carbon cold heading steel. The specimen at high finish rolling temperature exhibits very good mechanical properties due to fast cooling. This result has great significance not only for energy saving and emission reduction, but also for low-carbon economy, because the goals of the replacement of medium-carbon by low-carbon are achieved with TMCP.

  5. Co-precipitation of copper and niobium carbide in a low carbon steel

    Science.gov (United States)

    Gagliano, Michael Scott

    Co-precipitation of niobium carbide and body-centered cubic (BCC) copper in ferrite was investigated as a high strength, low carbon, chromium-free alternative to conventional high performance structural steels that rely on a tempered martensitic microstructure. Theoretical nucleation and growth rate models for BCC copper and niobium carbide were constructed using calculated thermodynamic driving forces in conjunction with classical theories for the homogeneous nucleation and subsequent growth of coherent, spherical precipitates. The maximum calculated nucleation and growth rates for niobium carbide were found to be 1.0 x 106 nuclei/cm3s at 666°C and 1.0 nm/s at 836°C, respectively, for an austenitizing temperature of 1170°C. For BCC copper in ferrite, the maximum calculated nucleation and growth rates were determined to be 8.0 x 1015 nuclei/cm 3s at 612°C and 0.038 nm/s at 682°C, respectively, for all austenitizing temperatures. Three-dimensional atom probe (3DAP) microscopy revealed the presence of nano-scale BCC copper clusters in approximately the same number density predicted by the theoretical nucleation model. Using an experimentally determined "effective" activation energy for copper in iron, the normalized theoretical nucleation rate curve compared very well with the normalized hardness response after 5 minutes of aging and effectively described the experimental short-time aging behavior of a low carbon, niobium bearing steel. The size and morphological evolution as well as the growth and coarsening behavior of copper precipitates were investigated through conventional TEM during isothermal direct aging at 550°C for a niobium and niobium-free steel. Although niobium carbide precipitation was not characterized, niobium additions provided increased hardness upon direct aging and showed a much higher resistance to overaging, than a niobium-free steel, for long isothermal aging times. In both steels for aging times up to five hours, both 9R type and BCC

  6. Outbursts formation on low carbon and trip steel grades during hot-dip galvanisation

    Science.gov (United States)

    Petit, E. J.; Lamm, L.; Gilles, M.

    2004-12-01

    Low carbon and TRIP grade steels have been hot dip galvanised in order to study outbursts formation. Microstructure and texture of intermetallic phases have been observed after selective electrochemical etching by scanning electron microscopy. Potential versus time (chronopotentiometric) characteristics were recorded in order to monitor surface modifications. This combination of techniques enable to quantify and observe intermetallic phase one by one. The overall thickness of coating on both substrates are similar. However, microstructures of Fe-Zn intermetallic phases are very different on both grades. In particular, the V phase is dense on standard steel but develops a highly branched filament structure on TRIP steel. The transformation of V phase to d and G1 are limited on TRIP steel. Differences of texture provide clues for understanding mechanisms of formation of outbursts. They can account for the differences of mechanical properties and corrosion resistance. Silicon from the substrate influences the reactivity of TRIP steels due to capping and local reactions. La formation des outbursts a été étudiée sur un acier bas carbone et sur un acier TRIP galvanisés. Les épaisseurs des revêtements sont similaires. Néanmoins, les observations microscopiques et les érosions électrochimiques montrent que la répartition des phases intermétalliques et leurs microstructures diffèrent sensiblement en fonction de la nature du substrat. Ces différences expliquent les propriétés mécaniques et anticorrosions. L’encapsulation de la surface par les oxydes de silicium freine la transformation de la phase dzêta en delta et gamma sur l’acier TRIP.

  7. Spectroscopic investigation of plasma electrolytic borocarburizing on q235 low-carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Run [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Zhenjiang Watercraft College, Zhenjiang 212000, Jiangsu (China); Wang, Bin; Wu, Jie [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Xue, Wenbin, E-mail: xuewb@bnu.edu.cn [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Jin, Xiaoyue; Du, Jiancheng; Hua, Ming [Key Laboratory for Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2014-12-01

    Highlights: • The plasma discharge behaviors for PEB/C on steels were evaluated by OES. • Electron temperature, concentration, atomic ionization degree were calculated. • The decomposition mechanism of electrolyte and was analyzed. - Abstract: A plasma electrolytic borocarburizing process (PEB/C) in borax electrolyte with glycerin additive was employed to fabricate a hardening layer on Q235 low-carbon steel. Optical emission spectroscopy (OES) was utilized to investigate the spectroscopy characteristics of plasma discharge around the steel during PEB/C process. Some plasma parameters were calculated in terms of OES. The electron temperature and electron concentration in plasma discharge zone is about 3000–12,000 K and 2 × 10{sup 22} m{sup −3}–1.4 × 10{sup 23} m{sup −3}. The atomic ionization degrees of iron, carbon and boron are 10{sup −16}–10{sup −3}, and 10{sup −23}–10{sup −6}, 10{sup −19}–10{sup −4}, respectively, which depend on discharge time. The surface morphology and cross-sectional microstructure of PEB/C hardening layer were observed, and the electrolyte decomposition and plasma discharge behaviors were discussed.

  8. Microstructural evolution and mechanical behaviour of surface hardened low carbon hot rolled steel

    Energy Technology Data Exchange (ETDEWEB)

    Tewary, N.K. [Department of Metallurgy and Materials Engineering, Bengal Engineering and Science University, Shibpur, Howrah 711103 (India); Syed, B. [R and D Division, Tata Steel Limited, Jamshedpur 831007 (India); Ghosh, S.K., E-mail: skghosh@metal.becs.ac.in [Department of Metallurgy and Materials Engineering, Bengal Engineering and Science University, Shibpur, Howrah 711103 (India); Kundu, S. [R and D Division, Tata Steel Limited, Jamshedpur 831007 (India); Shariff, S.M.; Padmanabham, G. [Centre for Laser Processing, ARCI-Hyderabad, Balapur PO, AP 500005 (India)

    2014-06-01

    Surface hardening of low carbon hot rolled C–Mn steel has been successfully performed by high power diode laser with an achievable case depth of about 300 μm. The laser treated samples have been characterised using optical microscope, scanning electron microscope, transmission electron microscope, and X-ray diffraction techniques. Higher hardness level is achieved in laser surface hardened zone (≈300 HV) than in the base alloy region (≈140 HV). The variation in hardness as a function of distance across the laser tracks is observed during multi-track laser hardening. Laser hardened steel sheets show enhanced mechanical strength (YS: 383–443 MPa, UTS: 476–506 MPa) with the lowering of percentage total elongation (23–28%) compared to the base alloy (YS: 351 MPa, UTS: 450 MPa and total elongation is 32%). Strain hardening exponent (‘n’) has been evaluated from true tensile stress–strain diagram and it shows a similar nature for both base alloy and laser treated steels. The microstructure in the base alloy region consists of a mixture of ferrite and pearlite, whereas predominantly lath martensite is present in the laser hardened surface layer. The improvement of mechanical strength is discussed in terms of the formation of this hardened layer on the surface.

  9. Formation of Diffusion Layers by Anode Plasma Electrolytic Nitrocarburizing of Low-Carbon Steel

    Science.gov (United States)

    Kusmanov, S. A.; Kusmanova, Yu. V.; Naumov, A. R.; Belkin, P. N.

    2015-08-01

    The structure of the low-carbon steel after plasma electrolytic nitrocarburizing in the electrolyte containing acetonitrile was investigated. The cross-sectional microstructure, composition, and phase constituents of a modified layer under different processing conditions were characterized. It is shown that the electrolyte that contained ammonium chloride and acetonitrile provides the saturation of steel with nitrogen and carbon and the formation of the Fe4N and FeN0.05 nitrides, Fe4C carbide and other phases. The nitrogen diffusion decreases the austenitization temperature and results in the formation of martensite after the sample cooling in the electrolyte. The formation of a carbon and nitrogen source in a vapor-gas envelope (VGE) is investigated. The proposed mechanism includes evaporation of acetonitrile in the VGE, its adsorption on an anode with the following thermal decomposition, and also the acetonitrile reduction to amine with subsequent hydrolysis to ethanol that is determined with the use of chromatographic method. The aqueous solution that contained 10 wt.% NH4Cl and 10 wt.% CH3CN allows one to obtain the nitrocarburized layer with the thickness of 0.22 mm and microhardness up to 740 HV during 10 min at 850 °C. This treatment regime leads to the decrease in the surface roughness of steel R a from 1.01 μm to 0.17 μm.

  10. Mass Transfer Coefficient During Cathodic Protectionof Low Carbon Steel in Seawater

    Directory of Open Access Journals (Sweden)

    Ameel Mohammed Rahman

    2009-01-01

    Full Text Available The aim of this research is to calculate mass transfer coefficient, kd, during cathodic protection of low carbon steel in neutral seawater (3.5% W/V NaCl in distilled water with pH = 7. Two types of cathodic protection were used:First: Sacrificial anode cathodic protection (SACP were a pipeline of steel carrying seawater using zinc as a sacrificial anode and with variable temperatures ranged (0 – 45oC and volumetric flow rate ranged (5 – 900 lit/hr. It was found that the kd increases with increasing temperature and volumetric flow rate of seawater, where kd ranged (0.24×10-6 – 41.6×10-6 m/s.Second: Impressed current cathodic protection (ICCP technique adopting a rotating vertical steel cylinder in seawater with variable temperatures ranged (0 – 45oC and rotating velocity ranged (0 – 400 rpm. It was found that the kd increases with increasing temperature and rotating velocity, where kd ranged (7.25×10-6 – 36.82×10-6 m/s.

  11. Effect of Niobium on Isothermal Transformation of Austenite to Ferrite in HSLA Low-Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    CAO Jian-chun; LIU Qing-you; YONG Qi-long; SUN Xin-jun

    2007-01-01

    Using thermomechanical simulation experiment, the kinetics of the isothermal transformation of austenite to ferrite in two HSLA low-carbon steels containing different amounts of niobium was investigated under the conditions of both deformation and undeformation. The results of optical microstructure observation and quantitative metallography analysis showed that the kinetics of the isothermal transformation of austenite to ferrite in lower niobium steel with and without deformation suggests a stage mechanism, wherein there exists a linear relationship between the logarithms of holding time and ferrite volume fraction according to Avrami equation, whereas the isothermal transformation of austenite to ferrite in high niobium steel proceeds via a two stage mechanism according to micrographs, wherein, the nucleation rate of ferrite in the initial stage of transformation is low, and in the second stage,the rate of transformation is high and the transformation of residual austenite to ferrite is rapidly complete. Using carbon extraction replica TEM, niobium carbide precipitation for different holding time was investigated and the results suggested that NbC precipitation and the presence of solute niobium would influence the transformation of austenite to ferrite. The mechanism of the effect of niobium on the isothermal transformation was discussed.

  12. Study on Carburizing Kinetics of Low-carbon Steel at High-temperature and Short-term

    Institute of Scientific and Technical Information of China (English)

    Lu Sheng; Xiao Nianxin; Zhang Hailong

    2007-01-01

    In this paper, the carburizing kinetics of low-carbon steel at high-temperature and short-term in liquid cast-iron were studied by metallographic microscope, chemical analysis and so on, and the microstructure of carburized layer was also analyzed. The results show that the carburizing rate of low-carbon steel at high-temperature and short-term is so fast, and the microstructure of carburized layer possess higher carbon content, and cementite, pearlite and ferrite exist in carburized layer structure simultaneously. Besides, the kinetic equations of permeating layer forming have been presented, and the carburizing mechanism was preliminary discussed also.

  13. Static and Metadynamic Recrystallization of Low Carbon Steels During Mechanical Deformation

    Institute of Scientific and Technical Information of China (English)

    沈丙振; 方能炜; 沈厚发; 柳百成

    2004-01-01

    Static and metadynamic recrystallization models were developed with the coefficients determined by multiple nonlinear regression analyses to describe microstructure evolution in low carbon steels. The effects of initial grain size, deformation temperature, strain, and strain rate on the austenitic recrystallized volume fraction and grain size were studied using a Gleeble machine. The results show that deformation reduces the grain size when the recrystallized volume fraction is large. The static recrystallized volume fraction increases with increasing deformation temperature, strain, and strain rate, and decreasing initial grain size. The grain size during metadynamic recrystallization is independent of the deformation strain and the initial grain size. The recrystallized volume fraction, the grain size, and the grown grain size calculated by the correlations are consistent with the measured values.

  14. Processing of low Carbon steel by dual rolls equal channel extrusion

    Science.gov (United States)

    Rusz, S.; Cizek, L.; Salajka, M.; Kedron, J.; Tylsar, S.

    2014-08-01

    This paper introduces a new method of forming for achievement of grain structure refinement by processing in DRECE (Dual Rolls Equal Channel Extrusion) equipment. The DRECE device was developed at the VSB - Technical University of Ostrava. It allows grain refinement in strip plate with dimensions of 58 mm (width) × 2 mm (thickness) × 1000 mm (length). The influence of the number of passes on the mechanical properties and related structure refinement was examined experimentally. The effect of a heat treatment (500 °C/1 h/steady air) on the grain refinement of low carbon steel after severe plastic deformation is analysed. Through this novel technique, the grain structure can be converted into a submicron grain structure.

  15. Hot-Dip Aluminizing of Low Carbon Steel Using Al-7Si-2Cu Alloy Baths

    OpenAIRE

    Prashanth Huilgol; Suma Bhat; K. Udaya Bhat

    2013-01-01

    Hot-dip aluminizing of low carbon steel was done in molten Al-7Si-2Cu bath at 690°C for dipping time ranging from 300 to 2400 seconds. Characterization of the intermetallics layer was done by using scanning electron microscope with energy dispersive spectroscopy. Four intermetallic phases, τ5-Al7Fe2Si, θ-FeAl3, η-Fe2Al5, and τ1-Al2Fe3Si3, were identified in the reaction layer. τ5- Al7Fe2Si phase was observed adjacent to aluminum-silicon topcoat, θ-FeAl3 between τ5 and η-Fe2Al5, η-Fe2Al5 adjac...

  16. Investigation on process parameters affecting blanking of AISI 1006 low carbon steel

    Science.gov (United States)

    D'Annibale, Antonello; El Mehtedi, Mohamad; Panaccio, Lorenzo; Di Ilio, Antoniomaria; Gabrielli, Filippo

    2016-10-01

    A blanking apparatus was designed and built in order to study the effects of the process parameters on blanking low carbon steel disks, with particular reference to the study of punch-die gap influence and Brozzo's damage criterion by keeping punch and die fillet radii constant. The goal of the shearing tests was to optimize the gap between punch and die, according to the material damage and the force curves obtained by experimental tests. By using a 2D axis-symmetry FE model, the authors studied a set of parameters in order to reduce damage. After studying the material damage by a first simulation series, a second series was carried out in order to evaluate the punch-die gap effects on force-stroke trend; good results in term of external surface finish were obtained in the geometry of the final workpiece.

  17. Influence of high deformation on the microstructure of low-carbon steel

    Institute of Scientific and Technical Information of China (English)

    Florin Popa; Ionel Chicina; Dan Frunz; Ioan Nicodim; Dorel Banabic

    2014-01-01

    Low-carbon steel sheets DC04 used in the automotive industry were subjected to cold rolling for thickness reduction from 20%to 89%. The desired thickness was achieved by successive reductions using a rolling mill. The influence of thickness reduction on the micro-structure was studied by scanning electron microscopy. Microstructure evolution was characterized by the distortion of grains and the occur-rence of the oriented grain structure for high cold work. A mechanism of grain restructuring for high cold work was described. The occur-rence of voids was discussed in relation with cold work. The evolution of voids at the grain boundaries and inside the grains was also consid-ered. To characterize the grain size, the Feret diameter was measured and the grain size distribution versus cold work was discussed. The chemical homogeneity of the sample was also analyzed.

  18. Effect of transient change in strain rate on plastic flow behaviour of low carbon steel

    Indian Academy of Sciences (India)

    A Ray; P Barat; P Mukherjee; A Sarkar; S K Bandyopadhyay

    2007-02-01

    Plastic flow behaviour of low carbon steel has been studied at room temperature during tensile deformation by varying the initial strain rate of 3.3 × 10-4 s-1 to a final strain rate ranging from 1.33 × 10-3 s-1 to 2 × 10-3 s-1 at a fixed engineering strain of 12%. Haasen plot revealed that the mobile dislocation density remained almost invariant at the juncture where there was a sudden increase in stress with a change in strain rate and the plastic flow was solely dependent on the velocity of mobile dislocations. In that critical regime, the variation of stress with time was fitted with a Boltzmann type Sigmoid function. The increase in stress was found to increase with final strain rate and the time elapsed in attaining these stress values showed a decreasing trend. Both of these parameters saturated asymptotically at a higher final strain rate.

  19. Cyclic Deformation Behavior and Fatigue Crack Propagation of Low Carbon Steel Prestrained in Tension

    Directory of Open Access Journals (Sweden)

    J. G. Wang

    2009-01-01

    Full Text Available The tests were performed on low carbon steel plate. In the tension fatigue tests, two angle values (ϕ=0° and ϕ=45°, ϕ is the angle between the loading and the rolling direction have been chosen. The influence of strain path change on the subsequent initial work softening rate and the saturation stress has been investigated. Dislocation microstructure was observed by transmission electron microscopy. It was found that the strain amount of preloading in tension has obviously affected the cyclic softening phenomenon and the initial cyclic softening rate. It was observed that the reloading axial stress for ϕ=45° case increased more than that of ϕ=0° case, due to the anisotropism of Q235. In the fatigue crack propagation tests, the experimental results show that with increasing the pretension deformation degree, the fatigue crack growth rate increases, especially at the near threshold section.

  20. Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel

    OpenAIRE

    Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

    2017-01-01

    TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based o...

  1. Effect of B and B + Nb on the bainitic transformation in low carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Kangying, E-mail: kangying.zhu@arcelormittal.com [ArcelorMittal Maizieres, Research and Development, BP 30320, 57283 Maizieres-les-Metz Cedex (France); Oberbillig, Carla, E-mail: carla.oberbillig@arcelormittal.com [ArcelorMittal Maizieres, Research and Development, BP 30320, 57283 Maizieres-les-Metz Cedex (France); Musik, Celine, E-mail: celine.musik@arcelormittal.com [ArcelorMittal Maizieres, Research and Development, BP 30320, 57283 Maizieres-les-Metz Cedex (France); Loison, Didier, E-mail: didier.loison@arcelormittal.com [ArcelorMittal Maizieres, Research and Development, BP 30320, 57283 Maizieres-les-Metz Cedex (France); Iung, Thierry, E-mail: thierry.iung@arcelormittal.com [ArcelorMittal Maizieres, Research and Development, BP 30320, 57283 Maizieres-les-Metz Cedex (France)

    2011-05-15

    Research highlights: {yields} B retards slightly the bainite transformation kinetics. {yields} Combined addition of B + Nb delayed dramatically bainite transformation kinetics. {yields} B refines the microstructure and promotes lath morphology of bainite. {yields} Larger packets of laths and longer laths are observed in the B + Nb steel. {yields} More free boron/finer borocarbide precipitates on {gamma} grain boundaries in B + Nb steel. - Abstract: Development of new, advanced high and ultra-high strength bainitic steels requires the selection of the optimum balance of bainite promoting elements allowing the production of the desired bainitic microstructure over a wide range of cooling rates. The addition of boron or a combined addition of boron and niobium is well known to retard strongly the polygonal ferrite formation but very little knowledge has been acquired on the bainitic transformation. Therefore, the purpose of this study is to investigate the influence of boron and boron plus niobium on the bainite transformation kinetics, microstructural evolution and mechanical properties in a low carbon steel (Fe-0.05C-1.49Mn-0.30Si). Isothermal and continuous cooling transformation diagrams were determined and followed by a detailed quantitative characterisation of the bainite microstructure and morphology using complementary advanced metallographic techniques (FEG-SEM-EBSD, SIMS and TEM). The relationship between microstructure and hardness has been evaluated. Finally, results of SIMS and TEM analyses coupled with microstructural investigations enable to propose a mechanism to explain the effect of the synergy between boron and niobium on the bainitic transformation and the resultant microstructure.

  2. Bulging Behavior of Thin-walled Welded Low Carbon Steel Tubes

    Directory of Open Access Journals (Sweden)

    XIE Wen-cai

    2017-01-01

    Full Text Available In order to investigate the deformation behaviour of welded tubes during hydraulic bulging process,the hydraulic bulging tests of thin-walled welded low carbon steel tubes (STKM11A were conducted on the tube hydroformability testing unit.The thickness distribution,profiles of bulging area and the strain distribution were all obtained.Results show that the thickness reduction of weld zone is just 2.4%-5.5% while its effective strain is just 0.05-0.10,which is very small and negligible compared with the parent material and means that just the geometric position of weld zone is changed with the continuous bulging.The thinnest points are located on the both sides of weld seam symmetrically and the angle between the thinnest point and weld seam is about 30°,at which the necking has been occurred.When the length of bulging area increases,the fracture pressure,the thickness reduction and the ultimate expansion ratio all decrease,and the profile of the bulging area gradually steps away from the elliptical model which is powerless for the ratio of length to diameter up to 2.0.Moreover,the strain state of the tube is transformed from biaxial tension to plane strain state with the increasing length of bulging area,on the basis of this the forming limit diagram of welded STKM11A steel tubes can be established.

  3. Reverse Austenite Transformation and Grain Growth in a Low-Carbon Steel

    Science.gov (United States)

    Garcin, Thomas; Ueda, Keiji; Militzer, Matthias

    2017-02-01

    The mechanisms controlling the reverse austenite transformation and the subsequent grain growth are examined in a low-carbon steel during slow continuous heating. The ex-situ metallographic analysis of quenched samples is complemented by in-situ dilatometry of the phase transformation and real-time laser ultrasonic measurements of the austenite grain size. Although the initial state of the microstructure (bainite or martensite) has only limited impact on the austenite transformation temperature, it has significant influence on the mean austenite grain size and the rate of grain growth. The coarsening of austenite islands during reverse transformation occurring from the martensitic microstructure is responsible for a large austenite grain structure at the completion of the austenite formation. On the other hand, a much finer austenite grain size is obtained when the austenite transforms from the bainite microstructure. Upon further heating, the rate of austenite grain growth is limited by the presence of nanometric precipitates present in the bainite microstructure leading to a significantly finer austenite grain size. These results give important guidance for the design of thermomechanical-controlled processing of heavy-gage steel plates.

  4. Experimental Study on Vacuum Carburizing Process for Low-Carbon Alloy Steel

    Science.gov (United States)

    Wei, Shaopeng; Wang, Gang; Zhao, Xianhui; Zhang, Xiaopeng; Rong, Yiming

    2013-10-01

    As a low-carbon alloy steel, 20Cr2Ni4A steel has an excellent mechanical properties. It has been used for producing heavy-duty gears, which require good wear and fatigue resistance. The vacuum carburizing process can improve the quality of gears and extend the service life. In this article, a complete heat-treatment process for 20Cr2Ni4A, with carburizing, tempering, quenching and cryogenic steps involved, was proposed. A numerical method was employed to design the carburizing step. The carburized samples were characterized by analysis of carbon profile, surface-retained austenite content, microstructure, and hardness profile. A good microstructure was obtained with acicular-tempered martensite, less-retained austenite, fine granular-dispersed carbides, and was oxide free. The final surface hardness was 64.2HRC, and the case depth was 0.86 mm, which meet the requirements of products. The relationships among process, performance, and microstructure were investigated to understand the inner connection.

  5. Study of the Deburring Process for Low Carbon Steel by Plasma Electrolytic Oxidation

    Science.gov (United States)

    Li, Hongtao; Kan, Jinfeng; Jiang, Bailing; Liu, Yanjie; Liu, Zheng

    2016-08-01

    In an appropriate electrochemical environment, the discrete thermal electron emission could be induced in the micro area due to the uneven distribution of electron flux on the anode surface. Thus an oxygen molecule could be ionized at the liquid-solid interface after collision, and then oxygen plasma with distribution characteristics would be formed. The plasma electrolytic oxidation (PEO) could happen at the liquid-solid interface. In this work, the low carbon steel was used to study the deburring process by PEO at a high frequency (70000 Hz) pulse DC mode. Its burr height H from 3.23 mm to 0.04 mm was removed to form a smooth surface within 6 min. The values of corrosion potential and current density for the untreated sample were -0.667 V and 6.735×10-5 A/cm2, respectively. But for the treated sample, the corrosion potential and current density were relatively lower, -0.354 V and 1.19×10-7 A/cm2. Therefore, PEO was expected to be a new deburring method of carbon steel for the material processing field. supported by National Natural Science Foundation of China (No. 51571114) and Natural Science Foundation of Jiangsu Province, China (No. BK20130935)

  6. Characterizations of Dynamic Strain-induced Transformation in Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    Luhan Hao; Mingyue Sun; Namin Xiao; Dianzhong Li

    2012-01-01

    Dynamic strain-induced transformation of the low carbon steel Q(235) at 770℃ and 850℃ leads to fine ferrite grains. The microstructure characterization and mechanism of the fine ferrite grain were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electron backscattered diffraction (EBSD) technique. The results show that strain-induced microstructure is the mixed microstructure of ferrite and pearlite, with cementite randomly distributed on ferrite grain boundaries and the grains interiors. EBSD images of grain boundaries demonstrate that high angle grain boundaries (HAGBs) are dominant in both of the deformation induced microstructures occurring below and above A(e3) , with only a few low angle grain boundaries (LAGBs) existing in the grain interiors. It implies that the dynamic strain-induced transformation (DSIT) happens above and below A(e3) temperature and has the same phase transition mechanisms. The refinement of ferrite is the cooperative effect of DSIT and continuous dynamic recrystallization (CDRX) of ferrite. Besides, DSIT is deemed as an incomplete carbon diffusion phase transition through the analysis of microstructure and the previous simulated results. The strengths of the Q(235) steel with refined ferrite and pearlite structure get doubled than the initial state without treated by DSIT and the residual stress in the refined structure is partly responsible for the ductility loss.

  7. Production of Low-Carbon Magnetic Steel for the LHC Superconducting Dipole and Quadrupole Magnets

    CERN Document Server

    Bertinelli, F; Harlet, P; Peiro, G; Russo, A; Taquet, A

    2006-01-01

    In 1996 CERN negotiated a contract with Cockerill Sambre – ARCELOR Group for the supply of 50 000 tonnes of low-carbon steel for the LHC main magnets: this was the first contract to be placed for the project, and one of the single largest. In 2005 – after nine years of work – the contract is being successfully completed. This paper describes the steel specifically developed, known as MAGNETIL™, its manufacturing and quality control process, organization of production, logistics and contract follow-up. Extensive statistics have been collected relating to physical, mechanical and technological parameters. Specific attention is dedicated to magnetic measurements (coercivity and permeability) performed at both room and cryogenic temperatures, the equipment used and statistical results. Reference is also made to the resulting precision of the fineblanked laminations used for the magnet yoke. The technology transfer from the particle accelerator domain to industry is ongoing, for example for ...

  8. Prevention of burn-on defect on surface of hydroturbine blade casting of ultra-low-carbon refining stainless steel

    Directory of Open Access Journals (Sweden)

    Li Ling

    2008-08-01

    Full Text Available The burn-on sand is common surface defect encountered in CO2-cured silicate-bonded sand casting of hydroturbine blade of ultra-low-carbon martensitic stainless steel, its feature, causes and prevention measures are presented in this paper. Experiments showed that the burn-on defect is caused by oxidization of chromium in the molten steel at high temperature and can be effectively eliminated by using chromium-corundum coating.

  9. Prevention of burn-on defect on surface of hydroturbine blade casting of ultra-low-carbon refining stainless steel

    Institute of Scientific and Technical Information of China (English)

    Li Ling; Xie Huasheng; Huang Danzhong; Li Hankun; Tan Rui; Zhou Jingyi

    2008-01-01

    The burn-on sand is common surface defect encountered in CO2-cured silicate-bonded sand casting of hydroturbine blade of ultra-low-carbon martensitic stainless steel, its feature, causes and prevention measures are presented in this paper. Experiments showed that the bum-on defect is caused by oxidization of chromium in the molten steel at high temperature and can be effectively eliminated by using chromium-corundum coating.

  10. Microstructural Evolution of a Low-Carbon Steel during Application of Quenching and Partitioning Heat Treatments after Partial Austenitization

    NARCIS (Netherlands)

    Santofimia, M.J.; Zhao, L.; Sietsma, J.

    2008-01-01

    The “quenching and partitioning” (Q&P) process has been studied in a low-carbon steel containing 1.1 wt pct aluminum by heat treatments consisting of partial austenitization at 900 °C and subsequent rapid cooling to a quenching temperature in the range between 125 °C and 175 °C, followed by an isoth

  11. Population Evolution of Oxide Inclusions in Ti-stabilized Ultra-low Carbon Steels after Deoxidation

    Institute of Scientific and Technical Information of China (English)

    Wen YANG; Ying ZHANG; Li-feng ZHANG; Hao-jian DUAN; Li WANG

    2015-01-01

    Population density function (PDF),which can eliminate the arbitrariness caused by the choice of the num-ber and the size of bins compared to the well-used histograms,was introduced to analyze the amount of inclusions. The population evolution of oxide inclusions in forms of PDF in Ti-stabilized ultra-low carbon steels after deoxidation during industrial RH refining and continuous casting processes was analyzed using an automated SEM-EDS system. It was found that after deoxidation till the early stage of casting,the alumina inclusions exhibited a lognormal PDF distribution,and three factors including the existence of a large amount of alumina clusters,the generation of alumi-na from the reduction of Al-Ti-O inclusions and the reoxidation of molten steel were estimated as the reasons.The shape parameterσwas high after deoxidation and then decreased after Ti treatment,indicating that in a short period after deoxidation,the size of alumina inclusions was widely distributed.After Ti treatment,the distribution of inclu-sion size was more concentrated.The scale parameter m decreased with time during the whole refining process,indi-cating that the proportion of large inclusions decreased during refining.Contrarily,the Al-Ti-O inclusions presented a fractal PDF distribution except at the end of casting with fractal dimension D of 4.3,and the constant of propor-tionality C decreased with time during RH refining and increased during casting process.The reoxidation of steel by slag entrapped from ladle was considered as the reason for the lognormal PDF behavior of Al-Ti-O inclusions at the end of casting.

  12. Modeling of roughness effect on hydrogen permeation in a low carbon steel

    Directory of Open Access Journals (Sweden)

    Carreño, J. A.

    2003-12-01

    Full Text Available A model is presented to evaluate the effect of the roughness and the profile of concentration of hydrogen in a low carbon steel. The model takes advantage of the Fick's Second Law, to predict the transport of hydrogen in the steel. The problem is treated as a variational one and its space solution is made numerically by means of the Finite Elements Method, while the temporal equation is solved via the Finite Differences Method, in order to determine the concentration profiles of Hydrogen in the steel and to quantify the roughness effect. Simultaneously, bipotentiostatic hydrogen permeation test were performed to evaluate the coefficient of mass transfer.

    El presente trabajo modela el efecto de la rugosidad y el perfil de concentración de hidrógeno en un acero, tomando como punto de partida la segunda ley de Fick para explicar el transporte de hidrógeno en el acero. El problema se trata como un problema variacional y su solución espacial se hace numéricamente por el Método de Elementos Finitos, mientras que la temporal por el Método de Diferencias Finitas, siendo estas las herramientas utilizadas para determinar los perfiles de concentración y cuantificar el efecto superficial presentado en este tipo de fenómeno. Además, a partir de la teoría se obtienen ecuaciones algebraicas que determinan el efecto que tiene la preparación superficial y el coeficiente de transferencia de masa con la permeación y concentración de hidrógeno en el acero.

  13. Adsorption and corrosion-inhibiting effect of Dacryodis edulis extract on low-carbon-steel corrosion in acidic media.

    Science.gov (United States)

    Oguzie, E E; Enenebeaku, C K; Akalezi, C O; Okoro, S C; Ayuk, A A; Ejike, E N

    2010-09-01

    The inhibition of low-carbon-steel corrosion in 1M HCl and 0.5M H(2)SO(4) by extracts of Dacryodis edulis (DE) was investigated using gravimetric and electrochemical techniques. DE extract was found to inhibit the uniform and localized corrosion of carbon steel in the acidic media, affecting both the cathodic and anodic partial reactions. The corrosion process was inhibited by adsorption of the extracted organic matter onto the steel surface in a concentration-dependent manner and involved both protonated and molecular species. Molecular dynamics simulations were performed to illustrate the process of adsorption of some specific components of the extract.

  14. Microstructure Examinations in Corners of the Low-Carbon Steel Slabs from Continuos Caster Machine

    Directory of Open Access Journals (Sweden)

    Kwinta G.

    2016-12-01

    Full Text Available The exposed selvedge layers in slabs cast by the continuous process should be free from surface defects, which in most cases appear in the form of cracks on the casting surface and run to its interior. In addition to the parameters of the casting process, the occurrence of such defects depends on the chemical composition of cast steel, on the segregation of surface active elements and formation of the precipitates of carbides, nitrides and other phases. Due to the frequent occurrence of defects in corners of the slabs, non-destructive testing was performed on the mechanically cleaned surfaces of slabs. The test material was low-carbon API(American Petroleum Institute API 5L standard steel micro alloyed with Nb and Ti designed for the production of pipes to handle gas, oil and other liquid and gaseous fuels. Despite the use of different methods of inspection, i.e. ultrasonic, magnetic particle and penetrant, cracks were not traced in the examined material. Then, from the corners of the examined slabs, specimens were cut out for metallographic examinations. The main purpose of these examinations was to disclose the presence of possible cracks and micro cracks on the surfaces transversal and longitudinal to the direction of casting. At the same time, studies were conducted to establish the number and morphology of non-metallic inclusions in selvedge layers of the slab corners and axis. Additionally, hardness of the slabs was measured. The conducted studies revealed only some minor differences in the slab hardness along its axis (130 ÷ 135 HB and in selvedge layers (120 ÷ 123 HB.

  15. Recrystallization and formation of austenite in deformed lath martensitic structure of low carbon steels

    Science.gov (United States)

    Tokizane, M.; Matsumura, N.; Tsuzaki, K.; Maki, T.; Tamura, I.

    1982-08-01

    The effect of prior deformation on the processes of tempering and austenitizing of lath martensite was studied by using low carbon steels. The recrystallization of as-quenched lath martensite was not observed on tempering while the deformed lath martensite easily recrystallized. The behavior of austenite formation in deformed specimens was different from that in as-quenched specimens because of the recrystallization of deformed lath martensite. The austenitizing behavior (and thus the austenite grain size) in deformed specimens was controlled by the competition of austenite formation with the recrystallization of lath martensite. In the case of as-quenched (non-deformed) lath martensite, the austenite particles were formed preferentially at prior austenite grain boundaries and then formed within the austenite grains mainly along the packet, block, and lath boundaries. On the other hand, in the case of lightly deformed (30 to 50 pct) lath martensite, the recrystallization of the matrix rapidly progressed prior to the formation of austenite, and the austenite particles were formed mainly at the boundaries of fairly fine recrystallized ferrite grains. When the lath martensite was heavily deformed (75 to 84 pct), the austenite formation proceeded almost simultaneously with the recrystallization of lath martensite. In such a situation, very fine austenite grain structure was obtained most effectively.

  16. Annealing Characteristics of Ultrafine Grained Low-Carbon Steel Processed by Differential Speed Rolling Method

    Science.gov (United States)

    Hamad, Kotiba; Ko, Young Gun

    2016-05-01

    The annealing behavior of ultrafine grained ferrite in low-carbon steel (0.18 wt pct C) fabricated using a differential speed rolling (DSR) process was examined by observing the microstructural changes by electron backscatter diffraction and transmission electron microscopy. For this purpose, the samples processed by 4-pass DSR at a roll speed ratio of 1:4 for the lower and upper rolls, respectively, were annealed isochronally at temperatures ranging from 698 K to 898 K (425 °C to 625 °C) for 1 hour. The deformed samples exhibited a complex microstructure in the ferrite phase consisting of an equiaxed structure with a mean grain size of ~0.4 µm and a lamellar structure with a mean lamellar width of ~0.35 µm. The texture evolved during deformation was characterized by the rolling and shear components with specific orientations. After annealing at temperatures lower than 798 K (525 °C), the aspect ratio of the deformed grains tended to shift toward a unit corresponding to the equiaxed shape, whereas the grain size remained unchanged as the annealing temperature increased. At temperatures above 798 K (525 °C), however, some grains with a low dislocation density began to appear, suggesting that the starting temperature of static recrystallization in the severely deformed ferrite grains was 798 K (525 °C). The annealing texture of the present sample after heat treatment showed a uniform fiber texture consisting of α- and γ-components.

  17. Hot-Dip Aluminizing of Low Carbon Steel Using Al-7Si-2Cu Alloy Baths

    Directory of Open Access Journals (Sweden)

    Prashanth Huilgol

    2013-01-01

    Full Text Available Hot-dip aluminizing of low carbon steel was done in molten Al-7Si-2Cu bath at 690°C for dipping time ranging from 300 to 2400 seconds. Characterization of the intermetallics layer was done by using scanning electron microscope with energy dispersive spectroscopy. Four intermetallic phases, τ5-Al7Fe2Si, θ-FeAl3, η-Fe2Al5, and τ1-Al2Fe3Si3, were identified in the reaction layer. τ5- Al7Fe2Si phase was observed adjacent to aluminum-silicon topcoat, θ-FeAl3 between τ5 and η-Fe2Al5, η-Fe2Al5 adjacent to base material, and τ1-Al2Fe3Si3 precipitates within Fe2Al5 layer. The average thickness of Fe2Al5 layer increased linearly with square root of dipping time, while for the rest of the layers such relationship was not observed. The tongue-like morphology of Fe2Al5 layer was more pronounced at higher dipping time. Overall intermetallic layer thickness was following parabolic relationship with dipping time.

  18. Microstructure and texture evolution during tensile deformation of symmetric/asymmetric-rolled low carbon microalloyed steel

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Minghui, E-mail: minghui.cai@deakin.edu.au [Institute for Frontier Materials (IFM), Deakin University, Geelong VIC 3217 (Australia); Wei, Xing [R & D Centre of Wuhan Iron & Steel (Group) Corp (WISCO), Wuhan 430080 (China); Rolfe, Bernard [Institute for Frontier Materials (IFM), Deakin University, Geelong VIC 3217 (Australia); Hodgson, Peter D., E-mail: minghui.cai@deakin.edu.au [Institute for Frontier Materials (IFM), Deakin University, Geelong VIC 3217 (Australia)

    2015-08-12

    The deformation and fracture mechanisms of a low carbon microalloyed steel processed by asymmetric rolling (AsR) and symmetric rolling (SR) were compared by microstructural and texture evolutions during uniaxial tensile deformation. A realistic microstructure-based micromechanical modeling was involved as well. AsR provides more effective grain refinement and beneficial shear textures, leading to higher ductility and extraordinary strain hardening with improved yield and ultimate tensile stresses as well as promoting the occurrence of ductile fracture. This was verified and further explained by means of the different fracture modes during quasi-static uniaxial deformation, the preferred void nucleation sites and crack propagation behavior, and the change in the dislocation density based on the kernel average misorientation (KAM) distribution. The equivalent strain/stress partitioning during tensile deformation of AsR and SR specimens was modeled based on a two-dimensional (2D) representative volume element (RVE) approach. The trend of strain/stress partitioning in the ferrite matrix agrees well with the experimental results.

  19. Characterization of coarse bainite transformation in low carbon steel during simulated welding thermal cycles

    Energy Technology Data Exchange (ETDEWEB)

    Lan, Liangyun, E-mail: lanly@me.neu.edu.cn [School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819 (China); State Key Laboratory of Rolling Technology and Automation, Northeastern University, Shenyang 110819 (China); Kong, Xiangwei [School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819 (China); Qiu, Chunlin [State Key Laboratory of Rolling Technology and Automation, Northeastern University, Shenyang 110819 (China)

    2015-07-15

    Coarse austenite to bainite transformation in low carbon steel under simulated welding thermal cycles was morphologically and crystallographically characterized by means of optical microscope, transmission electron microscope and electron backscattered diffraction technology. The results showed that the main microstructure changes from a mixture of lath martensite and bainitic ferrite to granular bainite with the increase in cooling time. The width of bainitic laths also increases gradually with the cooling time. For a welding thermal cycle with relatively short cooling time (e.g. t{sub 8/5} is 30 s), the main mode of variant grouping at the scale of individual prior austenite grains changes from Bain grouping to close-packed plane grouping with the progress of phase transformation, which results in inhomogeneous distribution of high angle boundaries. As the cooling time is increased, the Bain grouping of variants becomes predominant mode, which enlarges the effective grain size of product phase. - Highlights: • Main microstructure changes and the width of lath structure increases with cooling time. • Variant grouping changes from Bain zone to close-packed plane grouping with the transformation. • The change of variant grouping results in uneven distribution of high angle grain boundary. • Bain grouping is main mode for large heat input, which lowers the density of high angle boundary.

  20. Effect of acicular ferrite on banded structures in low-carbon microalloyed steel

    Institute of Scientific and Technical Information of China (English)

    Lei Shi; Ze-sheng Yan; Yong-chang Liu; Xu Yang; Cheng Zhang; Hui-jun Li

    2014-01-01

    The effect of acicular ferrite (AF) on banded structures in low-carbon microalloyed steel with Mn segregation during both iso-thermal transformation and continuous cooling processes was studied by dilatometry and microscopic observation. With respect to the iso-thermal transformation process, the specimen isothermed at 550°C consisted of AF in Mn-poor bands and martensite in Mn-rich bands, whereas the specimen isothermed at 450°C exhibited two different morphologies of AF that appeared as bands. At a continuous cooling rate in the range of 4 to 50°C/s, a mixture of AF and martensite formed in both segregated bands, and the volume fraction of martensite in Mn-rich bands was always higher than that in Mn-poor bands. An increased cooling rate resulted in a decrease in the difference of martensite volume fraction between Mn-rich and Mn-poor bands and thereby leaded to less distinct microstructural banding. The results show that Mn segregation and cooling rate strongly affect the formation of AF-containing banded structures. The formation mechanism of microstructural banding was also discussed.

  1. Effect of Thermomechanical Controlled Processing on Mechanical Properties of 490 MPa Grade Low Carbon Cold Heading Steel

    Institute of Scientific and Technical Information of China (English)

    LI Zhuang

    2009-01-01

    Thermomechanical controlled processing (TMCP) of low carbon cold heading steel in different austenite conditions were conducted by a laboratory hot rolling mill.Effect of various processing parameters on the mechanical properties of the steel was investigated.The results showed that the mechanical properties of the low carbon cold heading steel could be significantly improved by TMCP without heat treatment.The improvement of mechanical properties can be attributed mainly to the ferrite grain refinement due to low temperature rolling.In the experiments the better ultimate tensile strength and ductility are obtained by lowering finishing cooling temperature within the temperature range from 650 ℃ to 550 ℃ since the interlamellar space in pearlite colonies become smaller.Good mechanical properties can be obtained in a proper austenite condition and thermomechanical processing parameter.The ferrite morphology has a more pronounced effect on the mechanical behavior than refinement of the microstructure.It is possible to realize the replacement of medium-carbon by low-carbon for 490 Mpa grade cold heading steel with TMCP.

  2. Effect of Some Process Variables on Nickel Electroplating of Low Carbon Steel

    Directory of Open Access Journals (Sweden)

    Oluleke OLUWOLE

    2011-06-01

    Full Text Available This research work investigated the effect of current density, bath concentration, bath solution volume and electroplating time on nickel electroplating of low carbon steel. Varying voltage between 0.3 and 0.8 V, bath concentration between 0.27 g/cm3 (0.79 mol/dm3 and 0.35 g/cm3 (1.02 mol/dm3, electroplating time between 10 and 30 minutes and bath solution volume between 200 and 700 cm3, the effect of these process variables on electroplating was studied. The temperature was kept in conformity with Watt’s method at 50 ±5°C. It was observed that a bath concentration of 0.31 g/cm3 (0.89 Mol/dm3 concentration gave the best nickel deposit at 0.5V for 15 minutes. This would correspond to a Watt solution of composition: nickel sulphate-230 g/l, nickel chloride-46.5 g/l and boric acid-30.8 g/l with a pH of 4.18. Higher Watt bath concentration did not yield good results as plating thickness decreased and there was no luster. It was also observed that increasing time of plating served to increase plating thickness and did not affect brightness of plating. However non-uniform nickel deposition was observed for longer plating time. Increase in voltage served to increase rate of electrodeposition with the exceptions of 0.7 V where a long streak of plating was observed on substrate instead of uniform plating and 0.8V where plating lacked brightness having a burnt appearance. Bath volumes of between 200-500 cm3 were observed to be best for the coupons used (15mm × 20mm. Bath volumes above 500 cm^3 gave black plating appearance.

  3. Chemical Changes at the Interface Between Low Carbon Steel and an Al-Si Alloy During Solution Heat Treatment

    OpenAIRE

    2011-01-01

    International audience; The aim of this work was to characterize the chemical changes during solid state solution heat treatment of a metallurgically bonded steel/Al-Si interface. For this purpose, low carbon steel plates covered with the A-S7G03 aluminium alloy (7wt%Si, 0.3wt%Mg analogous to A356) were prepared by dip coating, water-quenching to room temperature and reheating in the solid state at 480-560°C for 3 to 160 hours. Upon reheating at 535 °C, a reaction layer was observed to grow a...

  4. Effects of C and Mn elements on deformation-enhanced ferrite transformation in low carbon (Mn) steels

    Institute of Scientific and Technical Information of China (English)

    Rongfeng Zhou; Wangyue Yang; Rong Zhou; Zuqing Sun

    2005-01-01

    Effects of C and Mn contents on the deformation-enhanced ferrite transformation (DEFT) in low carbon (Mn) steels have been investigated by hot compression. The microstructures of 2-4μm ultra-fine equiaxed ferrite grains with minors distributed homogeneously can be obtained by DEFT in all the tested steels. The more pronounced refinement is achieved as the C or Mn content increasing because of the higher-density nucleating sites and lower growth rate. The effectiveness of C on the level of refinement is more obvious than that of Mn.

  5. Microstructure and Property of Mn-Nb-B Low Carbon Bainite High Strength Steel Under Ultra-fast Cooling

    Directory of Open Access Journals (Sweden)

    WANG Bing-xing

    2016-07-01

    Full Text Available Using the Mn-Nb-B low carbon bainite high strength steel with the reducing production technology as the research target, the deformation behavior and phase transformation behavior were studied by the thermal simulation testing machine. Combining with the characteristics of the medium and heavy plate production line, the controlled rolling and controlled cooling technology based on ultra-fast cooling were designed to produce low cost high strength construction machinery steel with superior comprehensive mechanical properties. The strengthening mechanisms such as grain refinement strengthening, precipitation strengthening are effective to produce the Mn-Nb-B low carbon bainite high strength steel. The yield strength and tensile strength of the product reach to 678MPa and 756 MPa respectively, the elongation A50 is 33% and the impact energy at -20℃ is 261J. The microstructure of the steel is composed of granular bainite, acicular ferrite and lath bainite. A large number of fine, point, granular M/A constituents and dislocation structures dispersively distributed inside the matrix, and also tiny and dispersed (Nb,Ti (C,N precipitates are observed by transmission electron microscopy.

  6. Optimization of chemical compositions in low-carbon Al-killed enamel steel produced by ultra-fast continuous annealing

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Futao, E-mail: dongft@sina.com [The State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); Du, Linxiu; Liu, Xianghua [The State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); Xue, Fei [College of Electrical Engineering, Hebei United University, Tangshan 063000 (China)

    2013-10-15

    The influence of Mn,S and B contents on microstructural characteristics, mechanical properties and hydrogen trapping ability of low-carbon Al-killed enamel steel was investigated. The materials were produced and processed in a laboratory and the ultra-fast continuous annealing processing was performed using a continuous annealing simulator. It was found that increasing Mn,S contents in steel can improve its hydrogen trapping ability which is attributed by refined ferrite grains, more dispersed cementite and added MnS inclusions. Nevertheless, it deteriorates mechanical properties of steel sheet. Addition of trace boron results in both good mechanical properties and significantly improved hydrogen trapping ability. The boron combined with nitrogen segregating at grain boundaries, cementite and MnS inclusions, provides higher amount of attractive hydrogen trapping sites and raises the activation energy for hydrogen desorption from them. - Highlights: • We study microstructures and properties in low-carbon Al-killed enamel steel. • Hydrogen diffusion coefficients are measured to reflect fish-scale resistance. • Manganese improves hydrogen trapping ability but decrease deep-drawing ability. • Boron improves both hydrogen trapping ability and deep-drawing ability. • Both excellent mechanical properties and fish-scale resistance can be matched.

  7. An X-ray diffraction study of corrosion products from low carbon steel

    Directory of Open Access Journals (Sweden)

    Morales, A. L.

    2003-12-01

    Full Text Available It was found in earlier work a decrease in the corrosion rate from low carbon steel when it was subjected to the action of a combined pollutant concentration (SO4-2 = 10-4 M + Cl- = 1.5 x 10-3 M. It was also found that large magnetite content of the rust was related to higher corrosion rates. In the present study corrosion products are further analyzed by means of X-ray diffraction to account for composition changes during the corrosion process. It is found that lepidocrocite and goethite are the dominant components for the short-term corrosion in all batches considered while for long-term corrosion lepidocrite and goethite dominates if the corrosion rate is low and magnetite dominates if the corrosion rate is high. The mechanism for decreasing the corrosion rate is related to the inhibition of magnetite production at this particular concentration.

    En un estudio anterior se encontró que la tasa de corrosión, de un acero al carbono, decrecía cuando se le sometía al efecto combinado de una mezcla de contaminantes (SO4-2 = 10-4 M + Cl- = 1,5 x 10-3 M. También, se concluyó que altos contenidos de magnetita en la herrumbre estaban asociados a altas tasas de corrosión. En este trabajo se retoman estas herrumbres para analizarlas por difractometría de rayos X para tomar en cuenta los cambios en composición durante el proceso corrosivo. Se encuentra que goethita y lepidocrocita son las componentes dominantes durante la etapa inicial del proceso en todos los experimentos. En cambio para tiempos largos de exposición, y si la tasa de corrosión es alta, la magnetita es el producto de corrosión dominante. El mecanismo que reduce la tasa de corrosión, en la mezcla mencionada anteriormente, está relacionado con la inhibición del proceso de producción de la magnetita en estas condiciones.

  8. Continuous Cooling Transformation Behavior and Kinetic Models of Transformations for an Ultra-Low Carbon Bainitic Steel

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-min; CAI Qing-wu; YU Wei; LIXiao-lin; WANG Li-dong

    2012-01-01

    The aim was to investigate transformation behavior and transformation kinetics of an ultra-low carbon bai- nitic steel during continuous cooling. Continuous cooling transformation (CCT) curves of tested steel were measured by thermal dilatometer and metallographic structures at room temperature were observed by optical microscope. Then transformation kinetic equation of austenite to ferrite as well as austenite to bainite was established by analyzing the relationship of lnln]-l/(1--f)] and lnt in the kinetic equation on the basis of processed experimental data. Finally, the measured and calculated kinetic behaviors of the steel during continuous cooling were compared and growth pat- terns of transformed ferrite and bainite were analyzed. Results showed that calculated result was in reasonable agree- ment with the experimental data. It could be concluded that the growth modes of transformed ferrite and bainite were mainly one dimension as the Avrami exponents were between 1 and 2.

  9. Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel

    Science.gov (United States)

    Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

    2017-01-01

    TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based on volume fraction or force fraction. According to digital image correlation and electron back-scatter diffraction analyses, very high strain hardening effect in the initial deformation stage and active twin formation in the interfacial region beneficially affected the overall homogeneous deformation in the TWIP-cored sheets without any yield point phenomenon occurring in the LC sheet and serrations occurring in the TWIP sheet, respectively. These TWIP-cored sheets can cover a wide range of yield strength, tensile strength, and ductility levels, e.g., 320~498 MPa, 545~878 MPa, and 48~54%, respectively, by controlling the volume fraction of TWIP-cored region, and thus present new applications to multi-functional automotive steel sheets requiring excellent properties.

  10. Tensile property improvement of TWIP-cored three-layer steel sheets fabricated by hot-roll-bonding with low-carbon steel or interstitial-free steel

    Science.gov (United States)

    Park, Jaeyeong; Kim, Jung-Su; Kang, Minju; Sohn, Seok Su; Cho, Won Tae; Kim, Hyoung Seop; Lee, Sunghak

    2017-01-01

    TWIP-cored three-layer steel sheets were newly fabricated by hot rolling of TWIP steel sheet surrounded by low-carbon (LC) or interstitial-free (IF) steel sheets. TWIP/LC or TWIP/IF interfaces were well bonded without pores or voids, while a few pearlites were thinly formed along the interfaces. The strengths and elongation of the TWIP-cored sheets increased as the volume fraction of TWIP-cored region increased, and were also well matched with the ones calculated by a rule of mixtures based on volume fraction or force fraction. According to digital image correlation and electron back-scatter diffraction analyses, very high strain hardening effect in the initial deformation stage and active twin formation in the interfacial region beneficially affected the overall homogeneous deformation in the TWIP-cored sheets without any yield point phenomenon occurring in the LC sheet and serrations occurring in the TWIP sheet, respectively. These TWIP-cored sheets can cover a wide range of yield strength, tensile strength, and ductility levels, e.g., 320~498 MPa, 545~878 MPa, and 48~54%, respectively, by controlling the volume fraction of TWIP-cored region, and thus present new applications to multi-functional automotive steel sheets requiring excellent properties. PMID:28067318

  11. Relationship Between Bake Hardening, Snoek-Köster and Dislocation-Enhanced Snoek Peaks in Coarse Grained Low Carbon Steel

    Directory of Open Access Journals (Sweden)

    Li Weijuan

    2016-09-01

    Full Text Available In the present work, specimens prepared from coarse grained low carbon steel with different prestrains were baked and then, their bake hardening (BH property and internal friction were determined. TEM was used to characterize the dislocation structure in BH treated samples. The measurements of internal friction in prestrained samples and baked samples were carried out using a multifunctional internal friction apparatus. The results indicate that, in coarse grained low carbon steel, the bake hardening properties (BH values were negative, which were increased by increasing the prestrain from 2 to 5%, and then were decreased by increasing the prestrain from 5 to 10%. In the specimen with prestrain 5%, the BH value reached the maximum value and the height of Snoek-Köster peak was observed to be the maximum alike. With increasing the prestrain, both of the BH value and Snoek-Köster peak heights are similarly varied. It is concluded that Snoek-Köster and dislocation-enhanced Snoek peaks, caused by the interactions between interstitial solute carbon atoms and dislocations, can be used in further development of the bake hardening steels.

  12. Hard Chromium Electroplating and Improvement the Properties by the Thermo Chemical Treatments (Solid Carburizing of Low Carbon Steel

    Directory of Open Access Journals (Sweden)

    Ahmed Salloum Abbas

    2009-01-01

    Full Text Available In this research the hard chromium electroplating process, which is one of the common methods of overlay coating was used, by using chromium acid as source of chromium and sulphuric acid as catalyst since the ratio between chromic acid and sulphuric acid is (100 : 1 consequently. Plating process was made by applying current of density (40 Amp / dm2 and the range of solution temperature was (50 – 55oC with different time periods (1-5 hr. A low carbon steel type (Ck15 was used as substrate for hard chromium electroplating. Solid carburization was carried out for hard chromium plating specimen at temperature (925oC with time duration (2 hr to be followed with quenching and tempering. The phase analysis was conducted by using X– ray diffraction. The examination results show that the chromium carbides in plating layer were (Cr23C6, Cr7C3. The microhardness of hard chromium plating specimen was measured, and the results show that the high hardness was about (907HV. After solid carburization the hardness values increase and the results show that the higher hardness for chromium plating layer on low carbon steel surface was (1276 HV. Wear apparatus type (Pin on Disc was used to study dry sliding wear properties of low carbon steel (As received and hard chromium plating specimens and solid carburized. The effect of applied normal load on wear rate was studied with weighting method using five normal loads (5, 10, 15, 20, 25 N at constant sliding speed (2.198 m / sec. The results reveal that the wear rate increases with the increasing of applied normal load. A good improvement in wear resistance was noticed for hard chromium plating specimens as compared with substrate specimen. It was also seen that, the improvement in wear resistance was (94% as compared with substrate metal when carburizing treatment is carried out on hard chromium plating specimens.

  13. Influence of state of Nb on recrystallization temperature during annealing in cold-rolled low-carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Toshio, E-mail: ogawa.m8b.toshio@jp.nssmc.com [Nagoya Works, Nippon Steel and Sumitomo Metal Corporation, 5-3 Tokai-machi, Tokai-shi, Aichi 476-8686 (Japan); Sugiura, Natsuko [Steel Research Laboratories, Nippon Steel and Sumitomo Metal Corporation, 20-1 Shintomi, Futtsu, Chiba 293-8511 (Japan); Maruyama, Naoki; Yoshinaga, Naoki [Kimitsu R and D Laboratories, Nippon Steel and Sumitomo Metal Corporation, 1 Kimitsu, Kimitsu, Chiba 299-1141 (Japan)

    2013-03-01

    The influence of state of Nb on recrystallization temperature during annealing in cold-rolled low-carbon steels was investigated. Two kinds of specimens showing a remarkable difference in recrystallization temperature were prepared. Differences in the features of Nb-containing precipitates larger than 3 nm were rarely observed, whereas differences in precipitates smaller than 3 nm were confirmed by atom-probe field-ion microscopy in each hot-rolled sheet. The difference in the recrystallization temperatures of both specimens probably originates in the state of Nb at the atomic scale before annealing.

  14. Fatigue Property of Nano-grained Delaminated Low-carbon Steel Sheet

    Institute of Scientific and Technical Information of China (English)

    X. Li; T.F. Jing; M.M. Lu; R. Xu; B.Y. Liang; J.W. Zhang

    2011-01-01

    Tension-tension fatigue life tests on nano-grained delaminated Iow-carbon steel sheet under different fatigue loads are carried out to study the fatigue properties of the steel. The three-dimensional microstructures of the steel are observed by TEM. In addition, the morphology of the fatigue fracture of the specimen under different loads is observed by SEM. The results show that micro-cracks form on the weak interface of the nano-grained steel under Iow-stress conditions, which hinders the propagation of the main cracks and reduces the fatigue crack propagation rate, resulting in the extending fatigue life of the steel.

  15. Low-carbon transition of iron and steel industry in China: carbon intensity, economic growth and policy intervention.

    Science.gov (United States)

    Yu, Bing; Li, Xiao; Qiao, Yuanbo; Shi, Lei

    2015-02-01

    As the biggest iron and steel producer in the world and one of the highest CO2 emission sectors, China's iron and steel industry is undergoing a low-carbon transition accompanied by remarkable technological progress and investment adjustment, in response to the macroeconomic climate and policy intervention. Many drivers of the CO2 emissions of the iron and steel industry have been explored, but the relationships between CO2 abatement, investment and technological expenditure, and their connections with the economic growth and governmental policies in China, have not been conjointly and empirically examined. We proposed a concise conceptual model and an econometric model to investigate this crucial question. The results of regression, Granger causality test and impulse response analysis indicated that technological expenditure can significantly reduce CO2 emissions, and that investment expansion showed a negative impact on CO2 emission reduction. It was also argued with empirical evidence that a good economic situation favored CO2 abatement in China's iron and steel industry, while achieving CO2 emission reduction in this industrial sector did not necessarily threaten economic growth. This shed light on the dispute over balancing emission cutting and economic growth. Regarding the policy aspects, the year 2000 was found to be an important turning point for policy evolution and the development of the iron and steel industry in China. The subsequent command and control policies had a significant, positive effect on CO2 abatement.

  16. Electrochemical Behavior and Microstructure of Recyclable Aluminium-magmesium Alloy Hot-dip Coating Deposited on Low Carbon Steel Substrates

    Institute of Scientific and Technical Information of China (English)

    Panomkorn KWAKHONG; Apichart ARTNASEAW; Chaiyaput KRUEHONG

    2015-01-01

    With the abundance and good corrosion resistance of aluminium, hot-dip technique was used to prepare the recycled Al with 8.2 mass% Mg alloy coating on low carbon steel substrates. Electrochemical behavior of this coating was investigated by an-odic polarization and open circuit potential measurement. Its microstructure and composition were observed by scanning electron microscope and energy-dispersive X-ray spectrometry, respectively. The long lasting corrosion performance of coated steels was in-vestigated under the salt fog spray test. From anodic polarization curves and open circuit potential, recycled Al with 8.2 mass% Mg coating performed adequate sacriifcial ability. At 0.40 V, current density of recycled Al with 8.2 mass% Mg alloy coating was about 200 000 times higher than that of pure recycled Al coating, and was about 0.5 times lower than that of Zn coating. The microstruc-ture of recycled Al with 8.2 mass% Mg alloy coating on the steel substrate consisted of Al3Mg2, Al-Fe intermetallic compound and Al matrix. The results from salt fog spray test showed that recycled Al with 8.2 mass% Mg alloy coated steel had similar corrosion resistance ability to Zn coated steel.

  17. Modeling of Reversible γ/α Transformations of Low Carbon Steels in the Intercritical Temperature Range

    Institute of Scientific and Technical Information of China (English)

    TamasRETI; ImreFELDE; HakanGUR

    2004-01-01

    A phenomenological kinetic model has been developed for the prediction of non-isothermal reversible incomplete transformations in low-carbon hypoeutectoid steels. The theoretical basis of the proposed method has its origin in a possible extension of the traditional Austin-Rickett kinetic differential equation. To critically assess the applicability of the model, a number of experiments based on computer simulations have been performed to predict the austenite/ferrite proeutectoid transformation in the temperature range of Ae1 to Ae3 on plain carbon hypoeutectoid steels. A comparison with published experimental data has verified that the model developed is reasonable both quantitatively and with respect to well-established trends. Extension of the method of prediction appears promising when the non-isothermal reactions occurring during heat treatment (such as carbide precipitation and dissolution) can be assumed to proceed in a reversible manner.

  18. Morphology and Precipitation Kinetics of MnS in Low-Carbon Steel During Thin Slab Continuous Casting Process

    Institute of Scientific and Technical Information of China (English)

    YU Hao; KANG Yong-lin; ZHAO Zheng-zhi; SUN Hao

    2006-01-01

    The morphology of manganese sulfide formed during thin slab continuous casting process in low-carbon steel produced by compact strip production (CSP) technique was investigated. Using transmission electron microscopy analysis, it was seen that a majority of manganese sulfides precipitated at austenite grain boundaries, the morphologies of which were spherical or close to the spherical shape and the size of MnS precipitates ranged from 30 nm to 100 nm. A mathematical model of the manganese sulfide precipitation in this process was developed based on classical nucleation theory. Under the given conditions, the starting and finishing precipitation temperatures of MnS in the continuous casting thin slab of the studied low-carbon steel are 1 189 ℃ and 1 171 ℃, respectively, and the average diameter of MnS precipitates is about 48 nm within this precipitation temperature range. The influences of chemical components and thermo-mechanical processing conditions on the precipitation behavior of MnS in the same process were also discussed.

  19. Mechanical properties of fine-grained dual phase low-carbon steels based on dynamic transformation

    Institute of Scientific and Technical Information of China (English)

    Haiwei Xu; Wangyue rang; Zuqing Sun

    2008-01-01

    The fine grained dual phase (FG-DP) steel with ferrite grains of 2-4.5 μm and martensite islands smaller than 3 μm was obtained through the mechanism of deformation-enhanced ferrite transformation (DEFT). Mechanical properties of the steel were tested at room temperature. The results indicated that with a similar volume fraction of martensite (about 20vol%), FG-DP steel ex-hibited a superior combination of higher strength and more rapid strain hardening at low strains compared with the coarse-grained dual phase (CG-DP) steel obtained by critical annealing. The combination of higher strength, large elongation, and more rapid strain hardening of FG-DP steel can be attributed to the fine ferrite grain and finely dispersed martensite islands. In addition, the uniformly distributed martensite islands in FG-DP steel have smaller interspaeing compared with that of CG-DP steel. So, at the initial plastic deformation stage, the plastic deformation of ferrite was restrained and more pronounced load was transferred from ferrite to marten-site. The plastic deformation of martensite in FG-DP steel started earlier.

  20. High-Temperature Mechanical Behavior and Fracture Analysis of a Low-Carbon Steel Related to Cracking

    Science.gov (United States)

    Santillana, Begoña; Boom, Rob; Eskin, Dmitry; Mizukami, Hideo; Hanao, Masahito; Kawamoto, Masayuki

    2012-12-01

    Cracking in continuously cast steel slabs has been one of the main problems in casting for decades. In recent years, the use of computational models has led to a significant improvement in caster performance and product quality. However, these models require accurate thermomechanical properties as input data, which are either unreliable or nonexistent for many alloys of commercial interest. A major reason for this lack of reliable data is that high-temperature mechanical properties are difficult to measure. Several methods have been developed to assess the material strength during solidification, especially for light alloys. The tensile strength during solidification of a low carbon aluminum-killed (LCAK; obtained from Tata Steel Mainland Europe cast at the DSP plant in IJmuiden, the Netherlands) has been studied by a technique for high-temperature tensile testing, which was developed at Sumitomo Metal Industries in Japan. The experimental technique enables a sample to melt and solidify without a crucible, making possible the accurate measurement of load over a small solidification temperature range. In the current study, the tensile test results are analyzed and the characteristic zero-ductility and zero-strength temperatures are determined for this particular LCAK steel grade. The fracture surfaces are investigated following tensile testing, which provides an invaluable insight into the fracture mechanism and a better understanding with respect to the behavior of the steel during solidification. The role of minor alloying elements, like sulfur, in hot cracking susceptibility is also discussed.

  1. Toward the production of 50 000 tonnes of low-carbon steel sheet for the LHC superconducting dipole and quadrupole magnets

    CERN Document Server

    Babic, S; Beckers, F; Brixhe, F; Peiro, G; Verbeeck, T

    2002-01-01

    A total of 50 000 tonnes of low-carbon steel sheet has been ordered for the LHC main magnets. After three years of production, about 10 000 tonnes of steel sheet have been produced by Cockerill-Sambre Groupe Usinor. This paper gives a summary of the manufacturing process and improvements implemented as well as an overview of the difficulties encountered during this production. Preliminary statistics obtained for the mechanical and magnetic steel properties are presented. (6 refs).

  2. Towards the production of 50'000 tonnes of low-carbon steel sheet for the LHC superconducting dipole and quadrupole magnets

    CERN Document Server

    Babic, S; Brixhe, F; Comel, S; Peiro, G; Verbeeck, T

    2002-01-01

    A total of 50'000 tonnes of low-carbon steel sheet has been ordered for the LHC main magnets. After three years of production, about 10'000 tonnes of steel sheet have been produced by Cockerill-Sambre Groupe Usinor. This paper gives a summary of the manufacturing process and improvements implemented as well as an overview of the difficulties encountered during this production. Preliminary statistics obtained for the mechanical and magnetic steel properties are presented.

  3. Investigation on laser brazing AA6056 Al alloy to XC18 low-carbon steel

    Institute of Scientific and Technical Information of China (English)

    Jianjun Ding; Feiqun Li; Feng Qu; Patrice Peyre; Remy Fabbro

    2005-01-01

    @@ Based on the studies of influence of YAG laser heating conditions for Al alloy melt and steel on wettability,the mechanics of the laser overlap braze welding of 6056 Al and XC18 steel sheet has been investigated.Under the temperature range which is above the melting point of the Al alloy and below the melting point of the steel, two dissimilar metals can be joined by means of laser braze welding. There is no crack observed in the joining area, i.e. Al-Fe intermetallic phase (Fe3Al/FeAl/FeAl3/Fe2Al5) layer formed by solution and diffusion between liquid-solid interface. The temperature range can be defined as the process temperatures of laser braze welding of Al-Fe materials. Selecting a higher laser heating temperature can improve the wettability of Al melt to steel surface, but the intermetallic phase layer is also thicker. When the laser heating temperature is so high that the joining surface of steel is melted, there is a crack trend in the joining area.

  4. Corrosion Resistance and Pitting Behaviour of Low-Carbon High-Mn Steels in Chloride Solution

    Directory of Open Access Journals (Sweden)

    Grajcar A.

    2016-06-01

    Full Text Available Corrosion resistance of the X4MnSiAlNbTi27-4-2 and X6MnSiAlNbTi26-3-3 type austenitic steels, after hot deformation as well as after cold rolling, were evaluated in 3.5% NaCl solution using potentiodynamic polarization tests. A type of nonmetallic inclusions and their pitting corrosion behaviour were investigated. Additionally, the effect of cold deformation on the corrosion resistance of high-Mn steels was studied. The SEM micrographs revealed that corrosion damage formed in both investigated steels is characterized by various shapes and an irregular distribution at the metallic matrix, independently on the steel state (thermomechanically treated or cold worked. Corrosion pits are generated both in grain interiors, grain boundaries and along the deformation bands. Moreover, corrosion damage is stronger in cold deformed steels in comparison to the thermomechanically treated specimens. EDS analysis revealed that corrosion pits preferentially nucleated on MnS and AlN inclusions or complex oxysulphides. The morphology of corrosion damage in 3.5% NaCl supports the data registered in potentiodynamic tests.

  5. Design of duplex low carbon steels for improved strength: weight applications

    Energy Technology Data Exchange (ETDEWEB)

    Koo, J.

    1977-08-01

    Duplex ferrite-martensite (DFM) steels with excellent combinations of strength and formability have been selected from first principles, and their microstructure-property relationships established through a systematic investigation of a series of ternary Fe/X/0.1 C steels (X being varying amount of Cr and Si). Duplex processing consists of initial austenitization and quenching to form 100% martensite, followed by annealing in the (..cap alpha.. + ..gamma..) range and subsequent quenching. The resultant DFM morphology is controlled by the type and amount of alloying element X.

  6. Influence of grain size on radiation effects in a low carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Alsabbagh, Ahmad, E-mail: ahalsabb@ncsu.edu [Department of Nuclear Engineering, North Carolina State University (United States); Valiev, Ruslan Z. [Institute of Physics of Advanced Materials, Ufa State Aviation Technical University (Russian Federation); Murty, K.L. [Department of Nuclear Engineering, North Carolina State University (United States)

    2013-11-15

    Ultra-fine grain (UFG) metals with a relatively large volume of interfaces are expected to be more radiation resistant than conventional metals; grain boundaries act as unsaturable sinks for neutron irradiation induced defects. Effects of neutron irradiation on conventional and ultra-fine grain structured carbon steel are studied using the PULSTAR reactor at NC State University to relatively low fluence (∼1.15 × 10{sup −3} dpa). The low dose irradiation of ultrafine grained carbon steel revealed minute radiation effects in contrast to the observed radiation hardening and reduction of ductility in its conventional grained counterpart.

  7. Three-dimensional study of dislocation substructures in punch-stretched, AK, DQ, low-carbon steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Ledezma, M.

    1986-05-01

    Dislocation substructures developed in Aluminum Killed (AK), Drawing Quality (DQ), Low Carbon steel sheets during the Limiting Dome Height (LDH) test are investigated. Thin foils parallel to the sheet plane, longitudinal and transverse sections for different strain ratios have been observed by Transmission Electron Microscopy (TEM). Analysis of the cellular structure in three-dimensions allows the determination of the orientations of the cell wall planes inside individual ferrite grains. The observed cell wall planes for different strain ratios and grain orientations are compared with active slip planes calculated by using the Sach's model for polycrystal deformation. Cell walls are found to be roughly parallel to calculated slip planes for the range of strain ratios considered. Discrepancies observed in negative strain ratio samples are explained in terms of the validity of the Sach's model free-grain assumption.

  8. Continuous Cooling Bainite Transformation Characteristics of a Low Carbon Microalloyed Steel under the Simulated Welding Thermal Cycle Process

    Institute of Scientific and Technical Information of China (English)

    Xiangwei Kong; Chunlin Qiu

    2013-01-01

    Continuous cooling transformation of a low carbon microalloyed steel was investigated after it was subjected to the simulation welding thermal cycle process and the interrupted cooling test.Microstructure observation was performed by optical microscopy and transmission electron microscopy.On the basis of the dilatometric data and microstructure observation,the continuous cooling transformation (CCT) diagram was determined,which showed that the main microstructure changes from a mixture of lath martensite and bainitic ferrite to full granular bainite with the increase in the cooling time t8/5 from 10 to 600 s,accompanied with a decrease in the microhardness.The interrupted cooling test confirmed that the bainitic ferrite can form attached to grain boundaries at the beginning of transformation even if the final microstructure contains a mixture of granular bainite and bainitic ferrite.

  9. Microstructures relevant to brittle fracture initiation at the heat-affected zone of weldment of a low carbon steel

    Science.gov (United States)

    Ohya, Kenji; Kim, Jongseop; Yokoyama, Ken'ichi; Nagumo, Michihiko

    1996-09-01

    Charpy toughness of the heat-affected zone (HAZ) of weldment of a low carbon steel has been investigated by means of an instrumented Charpy test and fractographic analysis. Microstructures were varied with thermal cycles simulating double-pass welding. The ductile-brittle transition temperature is the most deteriorated at an intermediate second-cycle heating temperature. The origin of the difference in the transition temperatures has been analyzed to exist in the brittle fracture initiation stage. Fractographic examination correlating with microstructural features has revealed that the brittle fracture initiation site is associated with the intersection of bainitic ferrite areas with different orientations rather than the martensite-austenite constituents. The role of the constraint of plastic deformation on the brittle fracture initiation is discussed.

  10. Effect of zirconium addition on the austenite grain coarsening behavior and mechanical properties of 900 Mpa low carbon bainite steel

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The ultra-free bainitic microstructure of a 900 MPa low carbon bainitic Cu-Ni-Mo-B steel was obtained by a newly developed relaxation precipitation control (RPC) phase transformation processing.In a pan-cake like prior-anstenite grain,the microstructure consisted of lath bainite,a little of abnormal granular bainite,and acicular ferrite.The effect of zirconium carbonitrides on the austenite grain coarsening behavior was studied by transmission electron microscopy (TEM).The results show that,the lath is narrower with increasing cooling rate.The ratio of all kinds of bainitic microstructure is proper with the intermediate cooling rate;and Zr-containing precipitates distribute uniformly,which restrains austenite grain growing in heat-affected welding zone.

  11. Influence of shielding gas composition on weld profile in pulsed Nd:YAG laser welding of low carbon steel

    Directory of Open Access Journals (Sweden)

    M Jokar

    2014-12-01

    Full Text Available Weld area and weld depth/width ratio can be considered to be of the most important geometrical factors in pulsed laser welding. The effects of carbon dioxide and oxygen additions to the argon shielding gas on the weld properties in pulsed laser welding of low carbon steel is investigated. Presence of carbon dioxide and oxygen up to 10 and 15 percent respectively decreases the weld geometrical factors. But, at higher levels of additions, the weld geometrical factors will increase. It is observed that the plasma plume temperature decreases from 6000K to 5500K with the addition of 15% carbon dioxide but increases to 7700K with 25% carbon dioxide addition. Increase in laser absorption coefficient, laser energy absorption, formation of oxide layer on the work-piece surface, exothermic reactions and their competitive effects can be considered as the competing phenomena involved in such a behavior in the weld profile

  12. Microstructure, Wear, and Corrosion Characteristics of TiC-Laser Surface Cladding on Low-Carbon Steel

    Science.gov (United States)

    El-Labban, Hashem F.; Mahmoud, Essam Rabea Ibrahim; Algahtani, Ali

    2016-04-01

    Laser cladding was used to produce surface composite layer reinforced with TiC particles on low-carbon steel alloy for improving the wear and corrosion resistances. The cladding process was carried out at powers of 2800, 2000, 1500, and 1000 W, and a fixed traveling speed of 4 mm/s. The produced layers are free from any cracks. Some of the TiC particles were melted and then re-solidified in the form of fine acicular dendrites. The amount of the melted TiC was increased by increasing the laser power. The hardness of the produced layers was improved by about 19 times of the base metal. Decreasing laser power led to hardness increment at the free surface. The improvement in wear resistance was reached to about 25 times (in case of 1500 W) of the base metal. Moreover, the corrosion resistance shows remarkable improvement after the laser treatment.

  13. Phase Evolution in Boride-Based Cermets and Reaction Bonding onto Plain Low Carbon Steel Substrate

    Science.gov (United States)

    Palanisamy, B.; Upadhyaya, A.

    2012-04-01

    Reaction sinter bonding is a process that aims to bond two materials for improvement in properties through reactive sintering technique. The process has been effectively used to sinter hard materials like borides in situ which not only possess excellent oxidation resistance, good corrosion resistance but also resistant to abrasive wear. Sinter bonding is a unique surface modification process achieved through powder metallurgy and is competent with other techniques like boronizing sintering and sinter-brazing since it eliminates the additional operations of heat treatment and assembly and removes the inherent setbacks with these processes. This study focuses on identifying the phase evolution mechanism using characterization tools like x-ray diffractometry and energy dispersive spectroscopy and study of sinter bonding of the boron containing precursors (Mo-Cr-Fe-Ni-FeB-MoB) onto plain carbon steel. A microstructure containing Fe-based matrix dispersed with complex borides develops with temperature in the tape cast sheets. A fivefold increase in hardness between plain carbon steel in wrought condition and sinter bonded steel was observed. The multilayer consisted of a reaction zone adjacent to the interface and was investigated with the composition profile and hardness measurements. A model of sinter bonding between the cermet and the steel has also been proposed.

  14. Optimization of the Process of Carburizing and Heat Treatment of Low-Carbon Martensitic Steels

    Science.gov (United States)

    Ivanov, A. S.; Greben'kov, S. K.; Bogdanova, M. V.

    2016-05-01

    Steel 24Kh2G2NMFB is studied after carburizing and different heat treatments. The hardness and microhardness of the surface layer and of the matrix are measured. The content of retained austenite is determined by the method of x-ray diffraction analysis. Heat treatment modes improving the structure of the surface layer after carburizing are suggested.

  15. Corrosion protection of low-carbon steel using exopolysaccharide coatings from Leuconostoc mesenteroides

    Science.gov (United States)

    Corrosion is one of the most serious and challenging problems faced worldwide by industry. This research investigates the inhibition of corrosive behavior of SAE1010 steel by bacterial exopolysaccharides. Electrochemical Impedance Spectroscopy was used to evaluate the corrosion inhibition of diffe...

  16. Development of Fine-Grained, Low-Carbon Bainitic Steels with High Strength and Toughness Produced Through the Conventional Hot-Rolling and Air-Cooling

    Science.gov (United States)

    Dhua, Sanjay Kumar; Sarkar, Partha Pratim; Saxena, Atul; Jha, Bimal Kumar

    2016-12-01

    Low-carbon bainitic steels have created enormous interest among scientists across the world in the past few decades because of their high strength, toughness, and weldability replacing the conventional quenched and tempered medium-carbon steels. Three experimental steels with varying alloy additions were made in a 100-kg laboratory induction furnace and cast into 100-mm-diameter cylindrical ingots. These ingots were hot-rolled and air-cooled to 6-mm plates in an experimental rolling mill with selected thermomechanical parameters. Steels processed through this process provided an ultrafine low-carbon bainitic microstructure with maximum yield strength (YS) and ultimate tensile strength (UTS) 575 and 705 MPa, respectively. The Charpy impact toughness of the experimental steels was excellent, and at 253 K (-20 °C), it varied from 114 to 170 Joules. Cu-B-added steel was found to give an optimum combination of strength, YS-575 MPa, and toughness, 114 J at 253 K (-20 °C). Thus, fine-grained, low-carbon bainitic steels could be developed with a proper combination of alloying elements and thermomechanical parameters even by air-cooling.

  17. Development of Fine-Grained, Low-Carbon Bainitic Steels with High Strength and Toughness Produced Through the Conventional Hot-Rolling and Air-Cooling

    Science.gov (United States)

    Dhua, Sanjay Kumar; Sarkar, Partha Pratim; Saxena, Atul; Jha, Bimal Kumar

    2016-09-01

    Low-carbon bainitic steels have created enormous interest among scientists across the world in the past few decades because of their high strength, toughness, and weldability replacing the conventional quenched and tempered medium-carbon steels. Three experimental steels with varying alloy additions were made in a 100-kg laboratory induction furnace and cast into 100-mm-diameter cylindrical ingots. These ingots were hot-rolled and air-cooled to 6-mm plates in an experimental rolling mill with selected thermomechanical parameters. Steels processed through this process provided an ultrafine low-carbon bainitic microstructure with maximum yield strength (YS) and ultimate tensile strength (UTS) 575 and 705 MPa, respectively. The Charpy impact toughness of the experimental steels was excellent, and at 253 K (-20 °C), it varied from 114 to 170 Joules. Cu-B-added steel was found to give an optimum combination of strength, YS-575 MPa, and toughness, 114 J at 253 K (-20 °C). Thus, fine-grained, low-carbon bainitic steels could be developed with a proper combination of alloying elements and thermomechanical parameters even by air-cooling.

  18. Phase-field modelling of microstructure formation during the solidification of continuously cast low carbon and HSLA steels

    Science.gov (United States)

    Böttger, B.; Apel, M.; Santillana, B.; Eskin, D. G.

    2012-07-01

    Cracking in continuous casting of steels has been one of the main problems for decades. Many of the cracks that occur during solidification are hot tears. To better understand the factors leading to this defect, microstructure formation is simulated for a low carbon (LCAK) and two high strength low alloyed (HSLA) steel grades during the initial stage of the process where the first solidified shell is formed inside the mould and where breakouts typically occur. 2D simulation is performed using the multiphase-field software MICRESS [1], which is coupled to the thermodynamic database TCFE6 [2] and the mobility database MOB2 [2], taking into account all elements which may have a relevant effect on the mechanical properties and structure formation during or subsequent to solidification. The use of a moving-frame boundary condition allows travelling through the entire solidification history starting from the slab surface, and tracking the morphology changes during growth of the shell. A heterogeneous nucleation model is included to permit the description of morphological transitions between the initial solidification and the subsequent columnar growth region. Furthermore, a macroscopic one-dimensional temperature solver is integrated to account for the transient and nonlinear temperature field during the initial stage of continuous casting. The external heat flux boundary conditions for this process were derived from thermal process data of the industrial slab caster. The simulation results for the three steel grades have been validated by thickness measurements of breakout shells and microstructure observation of the corresponding grades. Furthermore, the primary dendrite spacing has been measured across the whole thickness of the shell and compared with the simulated microstructures. Significant microstructure differences between the steel grades are discussed and correlated with their hot-cracking behavior.

  19. Study of the mechanical properties of low carbon content HSLA steels

    Directory of Open Access Journals (Sweden)

    Illescas, S.

    2009-12-01

    Full Text Available Two high strength low alloy steels (HSLA with the same bulk composition and slight microalloying content differences were studied. The main purpose of the study was to determine the effect of different heat treatments and the influence of vanadium (V on the microstructure and mechanical properties of the bainite present in each steel. For that purpose, standard tests were conducted to determine the hardness, toughness, tensile and yield stress of the different bainite-acicular ferrite structures found in both steels. The results show how the V content promoted the formation of acicular ferrite, resulting in a decrease in hardness and tensile strength while improving toughness.

    Se han estudiado dos aceros HSLA (high strength low alloy que presentan composiciones similares, a excepción del contenido en elementos microaleantes. El propósito del estudio es determinar el efecto del tratamiento térmico y la influencia del contenido en vanadio (V sobre la microestructura y las propiedades mecánicas de la bainita en cada uno de los aceros. Para ello, se han realizado ensayos de dureza, de impacto y de tracción para cada una de las estructuras bainíticas-ferrita acicular obtenidas por medio de los diferentes tratamientos térmicos realizados. Los resultados muestran como el contenido en V promueve la formación de ferrita acicular, presentando valores bajos de dureza y resistencia mecánica pero mejorando la tenacidad.

  20. Effects of Nitride on the Tribological Properties of the Low Carbon Alloy Steel

    Directory of Open Access Journals (Sweden)

    Yuh-Ping Chang

    2013-01-01

    Full Text Available The technology of composite heat treatment is used popularly for low friction and wear resistance of drive elements. A large number of papers about the heat treatment technology had been proposed. Especially, the nitride treatment has been used widely for the purpose of wear resistance and low friction in the industry. Therefore, the self-developed vertical ball/disk friction tester with the measurement system was used to study the effects of nitride on the tribological properties of the low carbon alloy steel—SCM415— in this study. The experiments were conducted under dry and severe wear conditions. The variations of friction coefficient and surface magnetization were simultaneously recorded during dynamic friction process. After each test, the microstructures of the wear particles were observed and analyzed under a SEM, and the depth of wear track is measured by means of a surface tester. According to the experimental results, the wear resistance of the specimens with carburizing-nitride is significantly larger than the case of nitride-carburizing. Moreover, the surface magnetization was especially larger for the case of nitride-carburizing. As a result, the wear particles always stay in the interfaces and the wear mechanism becomes complex. Therefore, it is necessary to put nitride after carburizing for the composite heat treatments.

  1. Microstructure and Mechanical Properties of a Dissimilar Friction Stir Weld between Austenitic Stainless Steel and Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    M.Jafarzadegan; A.Abdollah-zadeh; A.H.Feng; T.Saeid; J.Shen; H.Assadi

    2013-01-01

    Dissimilar fusion welding of austenitic stainless steels to carbon steels has some metallurgical and technical problems.It was suggested that the solid-state nature of friction stir welding (FSW) can overcome these problems and produce a sound weld with reliable mechanical properties.In this study,plates of 304 stainless steel and st37 steel were welded together by FSW at tool rotational speed of 600 r/min and welding speed of 50 mm/min.In the stir zone (SZ) of 304 stainless steel,the results showed a refined grain structure with some features of metadynamic recrystallization.In the SZ of st37 steel,the hot deformation of material in the austenite region produced small austenite grains.These grains transformed to fine ferrite and pearlite by cooling the material after FSW.The production of fine grains increased the hardness and tensile strength in the SZ of both sides with respect to their base metals (BMs).

  2. Mechanical properties and characteristics of nanometer-sized precipitates in hot-rolled low-carbon ferritic steel

    Institute of Scientific and Technical Information of China (English)

    Xiao-pei Wang; Ai-min Zhao; Zheng-zhi Zhao; Yao Huang; Liang Li; Qing He

    2014-01-01

    The microstructures and properties of hot-rolled low-carbon ferritic steel have been investigated by optical microscopy, field-emission scanning electron microscopy, transmission electron microscopy, and tensile tests after isothermal transformation from 600°C to 700°C for 60 min. It is found that the strength of the steel decreases with the increment of isothermal temperature, whereas the hole expan-sion ratio and the fraction of high-angle grain boundaries increase. A large amount of nanometer-sized carbides were homogeneously distrib-uted throughout the material, and fine (Ti, Mo)C precipitates have a significant precipitation strengthening effect on the ferrite phase because of their high density. The nanometer-sized carbides have a lattice parameter of 0.411-0.431 nm. After isothermal transformation at 650°C for 60 min, the ferrite phase can be strengthened above 300 MPa by precipitation strengthening according to the Ashby-Orowan mechanism.

  3. Characterization of complex (B + C) diffusion layers formed on chromium and nickel-based low-carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Pertek, A.; Kulka, M

    2002-12-30

    Combined surface hardening with boron and carbon was used for low-carbon chromium and nickel-based steels. The microstructure, boron contents, carbon profiles and chosen properties of borided layers produced on the carburized steels have been examined. These complex (B+C) layers are termed borburized layers. The microhardness profiles and wear resistance of these layers have been studied. In the microstructure of the borocarburized layer two zones have been observed: iron borides (FeB+Fe{sub 2}B) and a carburized layer. The depth (70-125 {mu}m) and microhardness (1500-1800 HV) of iron borides zone have been found. The carbon content (1.2-1.94 wt.%) and microhardness (700-950 HV) beneath iron borides zone have been determined. The microhardness gradient in borocarburized layer has been reduced in comparison with the only borided layer. An increase of distance from the surface is accompanied by a decrease of carbon content and microhardness in the carburized zone. The carbon and microhardness profiles of borided, carburized and borocarburized layers have been presented. A positive influence of complex layers (B+C) on the wear resistance was determined. The wear resistance of the borocarburized layer was determined to be greater in comparison with that for only borided or only carburized layers.

  4. NbC precipitates EELS spectra in a very low carbon microalloyed steel

    Directory of Open Access Journals (Sweden)

    Mancilla, J. E.

    2004-06-01

    Full Text Available In this paper a characterization study by transmission electron microscopy (TEM and electron energy loss spectroscopy (EELS of NbC precipitates in microalloyed steel is presented. The steel was hot rolled in a laboratory scale two-high reversing mill. The shape, size, location, and number of particles per unit area in the steel microstructure are reported. The particles were semi quantitatively analyzed for the heavier alloying elements using EDS, while EELS was used for the lighter elements, e. g. carbon and nitrogen. The EELS study of the precipitates reveals that the carbon is present as a compound (NbC without nitrogen.

    En este trabajo se presenta un estudio de caracterización por espectroscopia de pérdida de energía de electrones (EPEE realizado en un microscopio electrónico de transmisión de los precipitados de NbC en un acero microaleado. El acero se laminó en caliente en un laminador dúo reversible escala laboratorio. Las partículas de precipitados se caracterizaron en tamaños, formas y distribución y se analizaron semicuantitativamente para los elementos de aleación del acero más pesados, empleando un detector por dispersión de energías de rayos X, mientras que la EPEE se empleó para los elementos más ligeros, es decir, el carbono y el nitrógeno. El estudio por EPEE de los precipitados muestra que el carbono está presente como un compuesto (NbC sin que se haya encontrado nitrógeno en los mismos.

  5. Thermomechanical processing route to achieve ultrafine grains in low carbon microalloyed steels

    OpenAIRE

    2016-01-01

    .A new thermomechanical processing route is described for a microalloyed steel, with roughing deformation below the recrystallisation-stop temperature (T5%), followed by a rapid reheat to 1200 °C for 10s, and then finish deformation at the same temperature as the rough deformation. The new route focused on optimising the kinetics of strain-induced precipitation (SIP) and the formation of deformation-induced ferrite transformation (DITF). For comparative purposes, two experimental 0.06 wt% C s...

  6. Effect of Mg Addition on the Ferrite Grain Boundaries Misorientation in HAZ of Low Carbon Steels

    Institute of Scientific and Technical Information of China (English)

    Kai Zhu; Zhenguo Yang

    2011-01-01

    The relation between the Mg treatment and ferrite grain boundaries misorientation was investigated. The orientation imaging; microscopy technique based on electron backscattered diffraction technique (EBSD) was used in this work. It was found that the addition of 0.005 wt% Mg to the steel could evidently increase the ratio of acicular ferrite crystals appearing at large angles boundaries to each other, which was attributed to the nucleation of the second-phase particles by the Mg treatment. The EBSD techniques provide a powerful method to characterize and quantify the ferrite grain boundaries misorientation, in order to relate it to toughness.

  7. RECRYSTALLIZATION BEHAVIOR AND PRIOR AUSTENITE GRAIN BOUNDARY CORROSION IN THE PLANE STRAIN COMPRESSION CONDITION FOR A LOW CARBON X70 PIPELINE STEEL

    Institute of Scientific and Technical Information of China (English)

    Y.H. Li; J. Wang; Y.S. Li; Y. Y. Shan

    2004-01-01

    Recrystallization behavior of a low carbon X70 pipeline steel was studied in the plane strain compression condition. It was found that the dynamic recovery but no dynamic recrystallization occurred in the current experimental condition. A method for examining the prior austenite grain boundary corrosion was supposed.

  8. Vapor Corrosion Response of Low Carbon Steel Exposed to Simulated High Level Radioactive Waste

    Energy Technology Data Exchange (ETDEWEB)

    Wiersma, B

    2006-01-26

    A program to resolve the issues associated with potential vapor space corrosion and liquid/air interface corrosion in the Type III high level waste tanks is in place. The objective of the program is to develop understanding of vapor space (VSC) and liquid/air interface (LAIC) corrosion to ensure a defensible technical basis to provide accurate corrosion evaluations with regard to vapor space and liquid/air interface corrosion. The results of the FY05 experiments are presented here. The experiments are an extension of the previous research on the corrosion of tank steel exposed to simple solutions to corrosion of the steel when exposed to complex high level waste simulants. The testing suggested that decanting and the consequent residual species on the tank wall is the predominant source of surface chemistry on the tank wall. The laboratory testing has shown that at the boundary conditions of the chemistry control program for solutions greater than 1M NaNO{sub 3}{sup -}. Minor and isolated pitting is possible within crevices in the vapor space of the tanks that contain stagnant dilute solution for an extended period of time, specifically when residues are left on the tank wall during decanting. Liquid/air interfacial corrosion is possible in dilute stagnant solutions, particularly with high concentrations of chloride. The experimental results indicate that Tank 50 would be most susceptible to the potential for liquid/air interfacial corrosion or vapor space corrosion, with Tank 49 and 41 following, since these tanks are nearest to the chemistry control boundary conditions. The testing continues to show that the combination of well-inhibited solutions and mill-scale sufficiently protect against pitting in the Type III tanks.

  9. Effects of carbon percentage, Stelmor cooling rate and laying head temperature on tensile strength gain in low carbon steels

    Science.gov (United States)

    Gade, Surya Prakash

    Low carbon steel wire rods are used to produce finished products such as fine wire, coat hangers, staples, and roofing nails. These products are subjected to excessively high work hardening rates during wire drawing process resulting in a variation in wire tensile strength. This research analyzes the effects of carbon percentage, StelmorRTM cooling rate and laying head temperature on the tensile strength gain in wire drawn low carbon steels using design of experiments. The probable reasons for variations in tensile strength gain are analyzed by observing the microstructural changes during experiments. Microstructural analysis was done extensively using optical microscope and Transmission Electron Microscope (TEM) and it was found that the tensile strength gain variation is mainly caused by the increase in the dislocation density in wire rod and wire due to high cooling rate and high laying head temperature, within the range considered. This research concludes that a low carbon wire rod can be produced with minimum tensile strength gain, lower dislocation density and finer ferrite grain size by maintaining a low cooling rate in the StelmorRTM cooling zone and low laying head temperature, which is the temperature at which the wire rod coils are laid on the Stelmor RTM deck. It is also concluded from the results of the present study that: (1) The lowest tensile strength gain is for NS 1006T-3 (0.07 wt.% Carbon) with low cooling rate of 14°F/s and low laying head temperature of 1500°F. (2) The highest tensile strength gain is for NS 1006T-3 with high cooling rate of 26°F/s and high laying head temperature of 1650°F. (3) The effect of StelmorRTM cooling rate and laying head temperature and their interaction are found to be the significant factors causing the variation in wire tensile strength gain. The StelmorRTM cooling rate has the most significant effect on tensile strength gain among the three factors. (4) The effect of carbon percentage on wire tensile strength

  10. Low carbon steel corrosion damage prediction in rural and urban environments

    Directory of Open Access Journals (Sweden)

    Díaz, V.

    2003-12-01

    Full Text Available This paper presents an Artificial Neural Network (ANN model for the damage function of carbon steel, expressed in μm of corrosion penetration as a function of environmental variables. Working in the context of the Iberoamerican Atmospheric Corrosion Map Project, the experimental data comes as result of the corrosion of low alloy steel subtracts in three test sites in Uruguay, South America. In addition, we included experimental values obtained from short time kinetics studies, corresponding to special series from one of the sites. The ANN numerical model shows attractive results regarding goodness of fit and residual distributions. It achieves a RMSE value of 0.5 μm while a classical regression model lies in the range of 4.1 μm. Furthermore, a properly adjusted ANN model can be useful in the prediction of corrosion damage under different climatological and pollution conditions, while linear models cannot.

    Este artículo presenta la metodología de las redes neuronales artificiales (RNA como solución para el modelado de los valores experimentales obtenidos en los procesos de corrosión atmosférica. Se desarrolla el modelo de RNA para la función de daño, expresada en μm de penetración para el acero de bajo carbono en función de las variables medioambientales, en el contexto del Proyecto MICAT (Mapa Iberoamericano de Corrosión Atmosférica y programas de experimentación propios. Los datos experimentales son resultado de los estudios de calibración sobre sustratos ferrosos en tres sitios del territorio uruguayo, Sudamérica. Se incluyen, además, los valores experimentales obtenidos en los estudios de cinéticas iniciales, correspondientes a series especiales de cortos tiempos de exposición en una de las estaciones de ensayo. El modelo numérico de RNA muestra resultados con un valor de RMSE de 0,5 μm, en tanto el modelo de regresión clásico arroja un valor de 4,1 μm.

  11. Modeling of structure of double-phase low-carbon chromium steels

    Science.gov (United States)

    Zolotarevskii, N. Yu.; Titovets, Yu. F.; Samoilov, A. N.; Hribernig, G.; Pichler, A.

    2007-01-01

    A physical model for determining the relative amount of phase components and the size of ferrite grains after decomposition of austenite in the process of cooling of double-phase steels is suggested. The main products of austenite transformation, i.e., polygonal ferrite, pearlite, bainite, and martensite, are considered. The driving forces of the transformation and the concentration of carbon on the phase surface are determined with the use of methods of computational thermodynamics. The model is based on equations of the classical theory of nucleation and growth. It allows for the structural features of the occurrence of γ → α transformation and contain some empirical parameters. The latter are determined using data of dilatometric measurements of the kinetics of austenite transformation and metallographic measurements of the size of ferrite grains. The model is used for predicting the kinetics of the transformation under the complex cooling conditions implemented by the VOEST-ALPINE STAHL LINZ GmbH rolling mill within the computer system for control of mechanical properties of hot-rolled strip.

  12. An Electron Microscopy Study of Vein-like Grain Boundary Microstructure in Nitrocarburized Low Carbon Steels

    Institute of Scientific and Technical Information of China (English)

    Wanglin Chen; Cuilan Wu; Jianghua Chen; Aigui He

    2013-01-01

    The coarsened grain boundaries (GBs) with vein-like morphology frequently appear in the nitrogen diffusion layer of nitrocarburized carbon steels.The electron probe X-ray microanalysis shows that such vein-like GBs are rich in nitrogen and carbon atoms.Transmission electron microscopy and scanning electron microscopy further reveal that the coarsened GBs consist of γ'-nitrocarbide (Fe4(C,N)) and ε-nitrocarbide lamellas that are formed during nitrocarburizing due to high nitrogen concentration at GBs.it is shown that many of {111}<112> micro twins exist in the γ'-phase lamellas and thin ε-phase slices prefer to nucleate at their twin boundaries with the orientation relationship of {O001}ε//{111}γ'.Upon growing large γ'-lamellas may become faceted and thin ε-lamellas may grow thicker and become the main portions in the vein-like GBs.The microstructure evolution occurring in the vein-like GBs can be depicted as:α + [N]/[C] → γ' + [C,N] → ε-nitrocarbides.

  13. Effect of Prestrain on Fatigue Crack Growth in Low-carbon Steel

    Directory of Open Access Journals (Sweden)

    Melnikov B.E.

    2011-05-01

    Full Text Available The current procedures of fatigue design of marine pipeline components allow for extending service life by considering a certain portion of the crack growth well before it turns into the instable phase. In structural components of transport systems material may undergo plastic pre-strain during the construction. The effect of pre-strain on the crack growth may be different depending on the material properties. Fatigue crack propagation was examined in testing symmetrically notched specimens machined from pre-strained steel plate coupons. Non-simultaneous crack initiation and propagation at the notches was reduced to symmetrical scheme by a simple coordinate transformation procedure. It was found that tensile pre-strain up to 0.01 did not substantially change the crack growth rate related to the stress intensity factor scale. Further increase of plastic pre-strain of material up to 0.15 caused almost two-times slowing down the crack growth rate compared to that of virgin material.

  14. A Conceptual Model for the Interaction between Carbon Content and Manganese Sulphide Inclusions in the Short-Term Seawater Corrosion of Low Carbon Steel

    Directory of Open Access Journals (Sweden)

    Robert E. Melchers

    2016-05-01

    Full Text Available The critical role of manganese sulphide (MnS inclusions for the initiation of the short-term growth of pitting or localized corrosion of low carbon steels has long been recognized. Classical results show that pitting probability and pitting severity increases with increased sulphide concentration for low carbon steels as a result of magnesium sulphides acting as local cathodes for initiating pitting corrosion. However, the iron carbides (cementite in steels can also act as local cathodes for initiation of pitting corrosion. Herein it is proposed that there is competition between pits for cathodic area and that this will determine the severity of pitting and general corrosion observed in extended exposures. Preliminary experimental data for immersion exposures of up to 56 days in natural seawater of three low carbon steels show, contrary to conventional wisdom, greater pit depths for the steels with lower S content. However, the pit depth results are consistent with lower C/S ratios. This is considered to support the concept of cathodic competition between C and S. It is proposed that this offers explanations for a number of other phenomena, including the thus far unexplained apparently higher reactivity of some MnS inclusions.

  15. Transformation behavior in low carbon 13% chromium-3% copper stainless steel; Tei C-13%Cr-3%Cu ko no hentai kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Hara, T.; Uemori, R.; Miyasaka, A. [Nippon Steel Corp., Tokyo (Japan)

    2000-10-01

    Martensitic transformation and {gamma} {yields} {alpha} transformation behavior were investigated in low carbon 13% chromium stainless steels containing 2% nickel or 3% copper. The main conclusions are as follows: (1) Hardness of 2% nickel added low carbon 13% chromium steel was independent of cooling rate after hot working at large reduction. Structure of the steel was martensitic even after being subjected to such large reduction of 75%. This result suggests that ferritic transformation was hard to occur under an usual cooling rate because austenite phase was sufficiently stablized by the addition of chromium and nickel. (2) Austenite to ferrite transformation occurred only for the low carbon 13% chromium 3% copper steel without nickel even at the small cooling rate, such as 0.01K/s. This result was mainly attributed to the unstabilization of austenite phase which caused by the precipitation of {epsilon}-Cu. Furthermore, austenite of the steel becomes easy to transform to ferrite due to heavy hot working. This phenomenon was seemed to be caused by the increase in the area of austenite grain boundary owing to recrystallization. Thus, it was considered that the nucleation of {epsilon}-Cu at the grain boundaries promoted ferrite formation. (author)

  16. Microstructural features and microhardness of Fe-Mo-Nb-V-C low-carbon steel processed by high-pressure torsion: The significance of the initial structural state

    Science.gov (United States)

    Maier, Galina; Astafurova, Elena; Melnikov, Eugene; Naydenkin, Eugene; Smirnov, Alexander; Bataev, Vladimir; Dobatkin, Sergey

    2016-11-01

    The effect of the initial heat treatment (quenching or tempering) of low-carbon steel (Fe-Mo-Nb-V-C) on special features of the ultrafine-grained structure and microhardness produced by high-pressure torsion was investigated. High-pressure torsion promotes the more apparent refinement of structural elements of the steel (dpr = 55 nm for the quenched state and 74 nm for the tempered state) and an increase in structural homogeneity of microhardness of quenched specimens in comparison with tempered ones. Experimental results reveal a high significance of the initial structural state for the final deformation-processed microstructure and microhardness (radial distribution) of steel specimens.

  17. An Experimental Investigation of Galvanic Anode Specifications for Suitable Cathodic Corrosion Protection of Low Carbon Steel in Kaduna Metropolitan Soil

    Directory of Open Access Journals (Sweden)

    T.N. Guma

    2016-06-01

    Full Text Available The paper stresses corrosion risks from huge underground engineering steel structures within the metropolitan area of Kaduna-a top city in Nigeria. Cathodic protection (CP is examined as an effective, economical and durable method of preventing corrosion of such structures if suitably designed-installed. Variables that can cause wide differences and difficulties in CP designs such as material make, surface area and nature of structure, corrosivity level of environment, etc, are recognized. Some supplementary information that accounts for complexity of such variables which can be used to optimize CP design of the structures was sought experimentally. Relative performances by zinc, pure magnesium and magnesium alloy as common and cheap galvanic anodes were investigated in a laboratory CP of polished bare low carbon steel specimens in soil of surveyed resistivity spectrum 31.9-152.9 ohm-m from the area. Specimens were exposed with and without CP by the anodes at ambient temperature up to 40 days in various samples of the soil. Levels of specimen protections were determined by analysis of obtained information on their corrosion rates and polarized potentials relative to the un-protected ones at 8-day intervals. The analysis indicated that; corrosion of the structures can be optimally reduced to negligible rates by polarizing them to -0.85V versus Cu/CuSO4 electrode with the anodes, pure magnesium is comparatively the best of the anodes for CP of the structures in terms of economy and effectiveness followed by magnesium alloy, and a unit surface area of the anodes can protect up to nearly 1200 units of the structure with the -0.85V protective potential depending on the anode type.

  18. A Model for Predicting the Yield Strength Difference between Pipe and Plate of Low-Carbon Microalloyed Steel

    Science.gov (United States)

    Zhang, Wenlong; Ding, Dongyan; Gu, Mingyuan

    2012-12-01

    A combination of finite-element calculation and tension-compression tests was employed to predict the yield strength difference between the pipe and plate of low-carbon microalloyed steel (LCMS) in the production of high-frequency straight bead welding pipes (HFSBWPs). The deformation process was divided into bending, flattening, and tension deformations. The bending and flattening deformations were simulated using a finite-element method in order to obtain circumferential strains at pipe wall positions along the wall thickness. These strains were the transition strains in the subsequent tension-compression-tension and compression-tension tests. The yield stresses (0.5 pct proof stresses) at the pipe wall positions were derived from the obtained stress-strain curves. The average of the obtained yield stresses was taken as the predicted yield strength of the pipes. It is found that the difference between the latter and the strength of the original steel plates is a result of the combined action of the Bauschinger effect and strain hardening caused by bending and reverse bending deformations. It is strongly dependent on the ratio of pipe wall thickness to pipe outer diameter ( T/D ratio). At low T/D ratios, the Bauschinger effect was dominant, resulting in a decreased yield strength. Strain hardening due to work hardening was dominant at higher T/D ratios, resulting in an increased yield strength. The increase in yield strength was greater at the inner pipe walls than at outer ones, indicating that strain hardening is stronger at inner pipe walls. The yield strength differences predicted with the presented approach are comparable with the values obtained from industrial productions of HFSBWPs, indicating that this approach can be used to predict the yield strength difference between pipe and plate of LCMS.

  19. Investigation of the Mechanical Properties of AISI 316 Austenitic Stainless Steel and St 37 Low Carbon Steel Dissimilar Joint by Friction Stir Welding

    Directory of Open Access Journals (Sweden)

    A.H. Khosrovaninezhad

    2015-07-01

    Full Text Available This paper reports on the mechanical properties of the dissimilar joints between AISI 316 austenitic stainless steel and St 37 low carbon steel achieved using friction stir welding technique. The welding was carried out by means of rotational speed of 800 rpm and linear speeds of 50,100,150 mm/min. EDS and XRD techniques were employed in order to determine possible phase transformations. Tensile test, shear punch test and microhardness measurements were conducted to evaluate the mechanical properties of the joints. The results of phase investigations showed that no carbide and brittle phase were detected at the joint boundary. Also, tensile test results demonstrated that failure occurred in the St 37 base metal. According to the shear punch test, the highest ultimate shear strength and yield shear strength was achieved for the sample welded at rotational speed of 800 rpm and linear speed of 150 mm/min, while this sample showed the least elongation. In addition, the highest microhardness was measured in the stir zone of austenitic stainless steel sample welded in the above mentioned welding condition, which can be attributed to the decrease in grain size caused by recrystallization process.

  20. Voltage-pulsed and laser-pulsed atom probe tomography of a multiphase high-strength low-carbon steel.

    Science.gov (United States)

    Mulholland, Michael D; Seidman, David N

    2011-12-01

    The differences in artifacts associated with voltage-pulsed and laser-pulsed (wavelength = 532 or 355 nm) atom-probe tomographic (APT) analyses of nanoscale precipitation in a high-strength low-carbon steel are assessed using a local-electrode atom-probe tomograph. It is found that the interfacial width of nanoscale Cu precipitates increases with increasing specimen apex temperatures induced by higher laser pulse energies (0.6-2 nJ pulse(-1) at a wavelength of 532 nm). This effect is probably due to surface diffusion of Cu atoms. Increasing the specimen apex temperature by using pulse energies up to 2 nJ pulse(-1) at a wavelength of 532 nm is also found to increase the severity of the local magnification effect for nanoscale M2C metal carbide precipitates, which is indicated by a decrease of the local atomic density inside the carbides from 68 ± 6 nm(-3) (voltage pulsing) to as small as 3.5 ± 0.8 nm(-3). Methods are proposed to solve these problems based on comparisons with the results obtained from voltage-pulsed APT experiments. Essentially, application of the Cu precipitate compositions and local atomic density of M2C metal carbide precipitates measured by voltage-pulsed APT to 532 or 355 nm wavelength laser-pulsed data permits correct quantification of precipitation.

  1. The Effect of Temperature and Acid Concentration on Corrosion of Low Carbon Steel in Hydrochloric Acid Media

    Directory of Open Access Journals (Sweden)

    Anees A. Khadom

    2009-01-01

    Full Text Available Problem statement: The effect of different temperatures and acid concentrations on the corrosion of low carbon steel in hydrochloric acid were addressed in this study. Approach: The effect of temperature was explained by application of Arrhenius equation and transition state theory, while the acid concentration effect was explained using reaction kinetic equations. The combined effect of temperature and acid concentration then modeled using a nonlinear regression method. Results: A detail of thermodynamic parameters of activation (E, ΔH* and ΔS* and kinetic studies for the corrosion reaction were obtained. Nonlinear corrosion rates as a function of temperature and acid concentration equation were estimated with a good prediction corrosion rates values. Conclusion: The values of activation energy E and enthalpy of activation ΔH* decrease with increase in acid concentration indicating the increasing in reaction rate. Entropy of activation ΔS* tend to lower values with increasing in acid concentration which indicated that the activated complex was more orderly relative to the initial state. The corrosion reaction was approximately firs order reaction. The observed corrosion rate values from the experimental data were in a good agreement with that predicated by the mathematical equation.

  2. Microstructural evolution and mechanical properties of a low-carbon quenching and partitioning steel after partial and full austenitization

    Institute of Scientific and Technical Information of China (English)

    Wan-song Li; Hong-ye Gao; Hideharu Nakashima; Satoshi Hata; Wen-huai Tian

    2016-01-01

    In this work, low-carbon steel specimens were subjected to the quenching and partitioning process after being partially or fully austenitized to investigate their microstructural evolution and mechanical properties. According to the results of scanning electron micros-copy and transmission electron microscopy observations, X-ray diffraction analysis, and tensile tests, upper bainite or tempered martensite appears successively in the microstructure with increasing austenitization temperature or increasing partitioning time. In the partially austeni-tized specimens, the retained austenite grains are carbon-enriched twice during the heat treatment, which can significantly stabilize the phases at room temperature. Furthermore, after partial austenitization, the specimen exhibits excellent elongation, with a maximum elongation of 37.1%. By contrast, after full austenitization, the specimens exhibit good ultimate tensile strength and high yield strength. In the case of a specimen with a yield strength of 969 MPa, the maximum value of the ultimate tensile strength reaches 1222 MPa. During the partitioning process, carbon partitioning and carbon homogenization within austenite affect interface migration. In addition, the volume fraction and grain size of retained austenite observed in the final microstructure will also be affected.

  3. A method for extracting phase change kinetics from dilatation for multistep transformations: Austenitization of a low carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Dykhuizen, R.C.; Robino, C.V.; Knorovsky, G.A. [Sandia National Labs., Albuquerque, NM (United States). Materials Joining Dept.

    1999-02-01

    This article describes the development of a method for determining phase change kinetics for multistep diffusion limited solid-state transformations from dilatation data. Since each step in a multistep reaction proceeds at a different rate, and the volume changes for the transformations are, in general, not equal, determination of the reaction kinetics from the dilatation data is not straightforward. Thus, a model is developed for the phase change process in which the transient dilatation is calculated based on the fractional extent of the various phases present. In this way, kinetic parameters are determined that allow the best match to the experimental data. However, both random and systematic experimental errors make reproduction of the experimental dilatation difficult. Therefore, a self-calibration process is developed that uses portions of the dilatation data to obtain the density variation of the various phases with temperature to help correct for experimental uncertainties. This procedure also enables the model to be used in situations where accurate property data are not available. The model and procedures are applied to the formation of austenite in a pearlite/ferrite low carbon steel where the pearlite and ferrite regions transform at different rates. A single kinetic parameter set allows reproduction of transformation transients of significantly different heating rates. These parameters can then be used to describe the austenitization for any time-temperature path. Excellent agreement between the model and experimental data is shown.

  4. Improvement in nano-hardness and corrosion resistance of low carbon steel by plasma nitriding with negative DC bias voltage

    Science.gov (United States)

    Alim, Mohamed Mounes; Saoula, Nadia; Tadjine, Rabah; Hadj-Larbi, Fayçal; Keffous, Aissa; Kechouane, Mohamed

    2016-10-01

    In this work, we study the effect of plasma nitriding on nano-hardness and corrosion resistance of low carbon steel samples. The plasma was generated through a radio-frequency inductively coupled plasma source. The substrate temperature increased (by the self-induced heating mechanism) with the treatment time for increasing negative bias voltages. X-rays diffraction analysis revealed the formation of nitride phases (ɛ-Fe2-3N and γ'-Fe4N) in the compound layer of the treated samples. A phase transition occurred from 3.5 kV to 4.0 kV and was accompanied by an increase in the volume fraction of the γ'-Fe4N phase and a decrease in that of the ɛ-Fe2-3N phase. Auger electron spectroscopy revealed a deep diffusion of the implanted nitrogen beyond 320 nm. The nano-hardness increased by ~400% for the nitrogen-implanted samples compared to the untreated state, the nitride phases are believed to participate to the hardening. Potentiodynamic polarization measurements revealed that the plasma nitriding has improved the corrosion resistance behavior of the material. When compared to the untreated state, the sample processed at 4.0 kV exhibits a shift of +500 mV and a reduction to 3% in its corrosion current. These results were obtained for relatively low bias voltages and short treatment time (2 h).

  5. Isothermal Reduction of Oxide Scale on Hot-Rolled, Low-Carbon Steel in 10 pct H2-Ar

    Science.gov (United States)

    He, Yongquan; Jia, Tao; Li, Zhifeng; Cao, Guangming; Liu, Zhenyu; Li, Jun

    2016-10-01

    The isothermal reduction of oxide scale on hot-rolled, low-carbon steel strip in 10 pct H2-Ar mixtures in the temperature range of 673 K to 1073 K (400 °C to 800 °C) was investigated by using a thermo-gravimetric analyzer (TGA). During heating under an argon atmosphere, magnetite/iron eutectoid and proeutectoid magnetite in the oxide scale successively transformed into wüstite at a temperature above 843 K (570 °C). The kinetic plot of the isothermal reduction assumes a sigmoid shape, including induction, acceleration, and finally the decaying stage. Fitting the kinetic curve to mathematical models, the reaction at 1073 K (800 °C) and 773 K (500 °C) were determined to be controlled by phase-boundary-controlled reaction and three-dimensional growth of nuclei, respectively. The reduction product varies with temperature and itself affects the kinetics. Porous and dense iron were, respectively, obtained below and above 873 K (600 °C). A "rate-minimum" was observed at 973 K (700 °C) due to the formation of dense iron that blocks the gas diffusion. Due to the structural transformation of oxide scale during heating, the reactant depends on the heating process. However, compared with the oxide scale structure, the temperature is more important in determining the reduction kinetics at temperatures above 973 K (700 °C).

  6. Fracture process of a low carbon low alloy steel relevant to charpy toughness at ductile-brittle fracture transition region

    Science.gov (United States)

    Tani, T.; Nagumo, M.

    1995-02-01

    The fracture process that determines the Charpy energy at the ductile-brittle transition region was investigated by means of the instrumented Charpy test and fractographic analysis with a low carbon low alloy steel subjected to different control-rolling conditions. The decomposition of a Charpy energy into the energies dissipated in the course of the notch-tip blunting, stable crack growth, and brittle crack propagation is unique irrespective of the testing temperatures and specimen series. Toughness level can be divided into four regions according to the pre-dominating fracture process. The temperature dependence of toughness and effects of the an-isotropy of a specimen originates in the brittle fracture initiation stage rather than the resistance against the notch-tip blunting or stable crack growth. From fractographic examination referring to the stress analyses, it is discussed that the brittle fracture initiation is controlled by the local deformation microstructures in the plastic zone together with the stress field ahead of the notch or the stable crack front.

  7. Preparation Femtosecond Laser Prevention for the Cold-Worked Stress Corrosion Crackings on Reactor Grade Low Carbon Stainless Steel

    CERN Document Server

    John Minehara, Eisuke

    2004-01-01

    We report here that the femtosecond lasers like low average power Ti:Sapphire lasers, the JAERI high average power free-electron laser and others could peel off and remove two stress corrosion cracking (SCC) origins of the cold-worked and the cracking susceptible material, and residual tensile stress in hardened and stretched surface of low-carbon stainless steel cubic samples for nuclear reactor internals as a proof of principle experiment except for the third origin of corrosive environment. Because a 143 °C and 43% MgCl2 hot solution SCC test was performed for the samples to simulate the cold-worked SCC phenomena of the internals to show no crack at the laser-peered off strip on the cold-worked side and ten-thousands of cracks at the non-peeled off on the same side, it has been successfully demonstrated that the femtosecond lasers could clearly remove the two SCC origins and could resultantly prevent the cold-worked SCC.

  8. Conservation Research and Development/ New Ultra-Low Carbon High Strength Steels with Improved Bake Hardenability for Enhanced Stretch Formability and Dent Resistance

    Energy Technology Data Exchange (ETDEWEB)

    Anthony J. DeArdo; C. Isaac Garcia

    2003-12-15

    Conservation Research and Development/New Ultra-Low Carbon High Strength Steels with Improved Bake Hardenability for Enhanced Stretch Formability and Dent Resistance. The experimental work can be divided into four phases. In each phase, the materials were received or designed, processed and tested, to evaluate the BH increment or response, as a function of compositions and processing conditions. Microstructural characterization by various techniques was performed in order to gain insights into the mechanisms of flow stress increment by bake hardening.

  9. Corrosion of low-carbon steel under environmental conditions at Hanford: Two-year soil corrosion test results

    Energy Technology Data Exchange (ETDEWEB)

    Anantatmula, R.P. [Westinghouse Hanford Co., Richland, WA (United States); Divine, J.R. [ChemMet Ltd., West Richland, WA (United States)

    1995-11-01

    At the Hanford Site, located in southeastern Washington state, nuclear production reactors were operated from 1944 to 1970. The handling and processing of radioactive nuclear fuels produced a large volume of low-level nuclear wastes, chemical wastes, and a combination of the two (mixed wastes). These materials have historically been packaged in US Department of Transportation (DOT) approved drums made from low-carbon steel, then handled in one of three ways: (A) Before 1970, the drums were buried in the dry desert soil. It was assumed that chemical and radionuclide mobility would be low and that the isolated, government-owned site would provide sufficient protection for employees and the public. (B) After 1970, the drums containing long-lived transuranic radionuclides were protected from premature failure by stacking them in an ordered array on an asphalt concrete pad in the bottom of a burial trench. The array was then covered with a large, 0.28-mm- (011-in.-) thick polyethylene tarp and the trench was backfilled with 1.3 m (4 ft) of soil cover. This burial method is referred to as soil-shielded burial . Other configurations were also employed but the soil-shielded burial method contains most of the transuranic drums. (C) Since 1987, US Department of Energy sites have complied with the Resource Conservation and Recovery Act of 1976 (RCRA) regulations. These regulations require mixed waste drums to be stored in RCRA compliant large metal sheds with provisions for monitoring. These sheds are provided with forced ventilation but are not heated or cooled.

  10. The efficiency of different types of wood charcoal on increasing carbon content on surfaces of low carbon steel in the pack carburizing process

    Directory of Open Access Journals (Sweden)

    Narongsak Thammachot

    2014-09-01

    Full Text Available The purpose of this research is to compare the efficiency of five types of wood charcoal, eucalyptus, coconut shell, tamarind, bamboo and cassava root in increasing carbon content on surfaces of low carbon steel by the pack carburizing process. The experiment for pack carburized low carbon steel (grade AISI 1020 was conducted by using the different wood charcoals as carburizers, mixed with 10% limestone (by weight as the energizer. The carburizing temperature of 950°C, and carburizing times of 2, 4 and 6 hours were used in the experiment. After grinding, the specimens in each case were checked for carbon content by optical emission spectroscopy. Micro-Vickers hardness testing and microstructure inspections were carried out. The results of the experiment showed that the efficiency of eucalyptus charcoal as the carburizer (for increasing carbon content on surfaces of low carbon steel was higher than that of tamarind, cassava root, coconut shell and bamboo charcoals. The averages for carbon content were: 1.16, 1.06, 0.97, 0.83 and 0.77% respectively.

  11. Surface characteristic of chemically converted graphene coated low carbon steel by electro spray coating method for polymer electrolyte membrane fuel cell bipolar plate.

    Science.gov (United States)

    Kim, Jungsoo; Kim, Yang Do; Nam, Dae Geun

    2013-05-01

    Graphene was coated on low carbon steel (SS400) by electro spray coating method to improve its properties of corrosion resistance and contact resistance. Exfoliated graphite was made of the graphite by chemical treatment (Chemically Converted Graphene, CCG). CCG is distributed using dispersing agent, and low carbon steel was coated with diffuse graphene solution by electro spray coating method. The structure of the CCG was analyzed using XRD and the coating layer of surface was analyzed using SEM. Analysis showed that multi-layered graphite structure was destroyed and it was transformed in to fine layers graphene structure. And the result of SEM analysis on the surface and the cross section, graphene layer was uniformly formed with 3-5 microm thickness on the surface of substrate. Corrosion resistance test was applied in the corrosive solution which is similar to the polymer electrolyte membrane fuel cell (PEMFC) stack inside. And interfacial contact resistance (ICR) test was measured to simulate the internal operating conditions of PEMFC stack. As a result of measuring corrosion resistance and contact resistance, it could be confirmed that low carbon steel coated with CCG was revealed to be more effective in terms of its applicability as PEMFC bipolar plate.

  12. Effects of Cr, Ni and Cu on the Corrosion Behavior of Low Carbon Microalloying Steel in a Cl-Containing Environment

    Institute of Scientific and Technical Information of China (English)

    Yanlei Zhou; Jun Chen; Yang Xu; Zhenyu Liu

    2013-01-01

    The effects of Cr,Ni and Cu on the corrosion behavior of low carbon microalloying steel in a Cl-containing environment were investigated.The results revealed that the corrosion process could be divided into the initial stage in which the corrosion rate increased with accumulation of corrosion products and the later stage in which homogeneous and compact inner rust layers started to protect steel substrate out of corrosion mediums.The results of X-ray diffraction (XRD) indicated that the rust layers of the three-group steels (Cr,Cr-Ni and Cr-Ni-Cu steels) were composed of α-FeOOH,β-FeOOH,γ-FeOOH,Fe3O4 and large amounts of amorphous compounds.The content of amorphous compounds of Cr-Ni-Cu steel was about 2%-3% more than that of Cr-Ni steel.The results of electron probe microanalysis (EPMA) showed that Cr concentrated mainly in the inner region of the rust of Cr-Ni-Cu steel,inner/outer interface especially,whereas Ni was uniformly distributed all over the rust and Cu was noticed rarely after 73 wet/dry cycles.The addition of Cr and Ni was beneficial to the formation of dense and compact inner rust layer,which was the most important reason for the improvement of corrosion resistance of experimental steel.

  13. Research on low carbon steel activating flux CMT welding%活性剂CMT焊接的研究

    Institute of Scientific and Technical Information of China (English)

    周方明; 宋辉

    2013-01-01

    The CO2 gas shielded welding has big spatter,and this will pollute the environment and affect the staff health.In this paper, we will study the activating flux CMT welding under the CO2 gas protection, to research a green and efficient welding technology.Through the active agent of low carbon steel CMT welding test,the results show that,CMT welding with active agent,you can make a higher degree of penetration increases, increasing 20% or more proportion.With the different active agent ingredients, the degree of weld penetration increases in different.In activating flux CMT welding,the active agent has an important impact on both the physical process of the arc electrode gas ionization and electron emission, and the active substance reduces the accession of ionization voltage to make the arc stability .The activating flux CMT welding make the penetration increase result of arc compression and surface tension.Especially, the B2O3 and SiO2 make the weld penetration increasing significantly, because of the two elements of B and Si have large resistively.%CO2气体保护焊飞溅较大,污染环境,影响人员健康.研究了CO2气体保护下的活性剂CMT焊接,旨在研究一种绿色高效的焊接技术.通过进行低碳钢的活性剂CMT焊接试验,研究结果表明:CMT焊接采用活性剂后,可以较大程度增加熔深,增加比例在20%以上.活性剂成分不同,焊缝熔深增加程度也不同.在活性剂CMT焊接中,活性剂对电弧气体电离和电极发射电子都产生重要影响,活性物质的加入使得电离电压降低,电弧稳定.活性剂CMT焊接使熔深增加是电弧压缩和表面张力共同作用的结果.其中B2O3和SiO2使焊缝熔深增加明显,与B和Si两元素具有较大的的电阻率有关.

  14. The use of morinda citrifolia as a green corrosion inhibitor for low carbon steel in 3.5% NaCl solution

    Science.gov (United States)

    Kusumastuti, Rahayu; Pramana, Rakhmad Indra; Soedarsono, Johny W.

    2017-03-01

    The effect and mechanism of green corrosion inhibitor of Morinda Citrifolia (Noni) toward low carbon steel material has been researched. The general background is to develop the cheap and eco-friendly corrosion inhibitor based on components taken from tropical plants that grow +in Indonesia. This research aims to determine the effectiveness of the use of the extracts of noni as green corrosion inhibitor of carbon steel material in aggressive environment. The medium applied for this experiment is 3.5% natrium chloride solution. The variation of the concentration and immersion time duration has been applied as the experimental parameters. All the work was done at room temperature. The corrosion rate was measured by electrochemical polarization method with CMS 600-Gamry instruments and weight loss. The adsorption of inhibitor into the metal surface, which induced bonding formation after immersion was observed by using FTIR method. Inhibition mechanism was observed by polarization curves and fitted by the Langmuir adsorption models. The experimental results show that the higher concentration of inhibitor increasing the inhibition effect. The optimum inhibition is obtained at 3 ppm noni fruit extract, after immersion for about 288 hours. The corrosion rates obtained was 1.385 mpy, with the inhibitor efficiency of 76.92%. The monolayer film is formed coating the surface material as a result of mixed type corrosion inhibitor behavior of Noni. It can be concluded that this green inhibitor is effective to be used for low carbon steel material.

  15. The morphology of Al-Ti-O complex oxide inclusions formed in an ultra low-carbon steel melt during the RH process

    Science.gov (United States)

    Doo, Won-Chul; Kim, Dong-Yong; Kang, Soo-Chang; Yi, Kyung-Woo

    2007-06-01

    Internal morphologies of bulk shape oxides in a melt of Ti bearing low-carbon steel were analyzed. The outer shapes of nearly spherical inclusions containing Ti were quite different from the shape of alumina inclusions that typically have a cluster form. A cross-section investigation using a polishing method and the FIB method revealed that the TiOx-Al2O3 complex oxide covers alumina clusters and that the interfaces of the alumina and complex oxide are modified as time passes.

  16. Effects of AlMnCa and AlMnFe Alloys on Deoxidization of Low Carbon and Low Silicon Aluminum Killed Steels

    Institute of Scientific and Technical Information of China (English)

    ZHAN Dong-ping; ZHANG Hui-shu; JIANG Zhou-hua

    2008-01-01

    To confirm the effects of AlMnCa and AIMnFe alloys on the deoxidization and modification of Al2O3 inclu-sions, experiments of 4-heat low carbon and low silicon aluminum killed steels deoxidized by AlMnCa and AlMnFe alloys were done in a MoSi2 furnace at 1 873 K. It is found that the 1# A1MnCa alloy has the best ability of deoxidi-zation and modification of Al2 O3 inclusions than 2# A1MnCa and A1MnFe alloys. Steel A deoxidized by 1# AlMnCa alloy has the lowest total oxygen content in the terminal steel, which is 37 × 10-6. Most of the inclusions in the steel deoxidized by 1# AIMnCa alloy are spherical CaO-containing compound inclusions, and 89. 1% of them are smaller than 10 μm. The diameter of the inclusion bigger than 50 μm is not found in the final steels deoxidized by AlMnCa alloys. Whereas, for the steels deoxidized by AlMnFe alloys, most inclusions in the terminal steel are Al2O3 or Al2O3-MnO inclusions, and a few of them are spherical, and only 76. 8% of them are smaller than 10 μm. Some in-clusions bigger than 50 μm are found in the steel D deoxidized by AlMnFe alloy.

  17. Effect of Strain Rate on the Ferrite Grain Refinement in a Low Carbon Nb-Ti Microalloyed Steel during Low Temperature Deformation

    Institute of Scientific and Technical Information of China (English)

    B.Eghbali; A.Abdollah-zadeh

    2005-01-01

    Grain refinement is one of the effective methods to develop new generation low carbon microalloyed steels possessing excellent combination of mechanical properties. The microstructural evolution and ferrite grain refinement at the de-formation temperature of 865℃, above Ar3, with different strain rates were investigated using single pass isothermal hot compression experiments for a low carbon Nb-Ti microalloyed steel. The physical processes that occurred during deformation were discussed by observing the optical microstructure and analyzing the true stress-true strain responses.At strain rates of 0.001 and 0.01 s-1, there is no evidence of work hardening behavior during hot deformation and strain-induced transformation (SIT) leads to dynamic flow softening in flow curves. Optical microscopy observation shows that ultrafine and equiaxed ferrite with grain sizes of 2μm can be obtained by applying deformation with strain rate of 0.1 s-1 due to SIT just after deformation. Furthermore, increasing the strain rate from 0.001 to 0.1 s-1reduces both the grain size of the equiaxed ferrite and the amount of deformed ferrite.

  18. Technological change and industrial energy efficiency : Exploring the low-carbon transformation of the German iron and steel industry

    NARCIS (Netherlands)

    Arens, M.

    2017-01-01

    Climate change is a key challenge of our time. The iron and steel industry emits 6.5 % of global anthropogenic CO2 that is likely to drive global warming. Greenhouse gases, among these CO2, are to be reduced to 5-20% of today’s level in industrialised countries. Thus, the steel sector must make sign

  19. Pathways to a low-carbon iron and steel industry in the medium-term – the case of Germany

    NARCIS (Netherlands)

    Arens, Marlene; Worrell, Ernst; Eichhammer, Wolfgang; Hasanbeigi, Ali; Zhang, Qi

    2016-01-01

    The iron and steel industry is a major industrial emitter of carbon dioxide globally and in Germany. If European and German climate targets were set as equal proportional reduction targets (referred to here as “flat” targets) among sectors, the German steel industry would have to reduce its carbon d

  20. Effect of V and V-N Microalloying on Deformation-Induced Ferrite Transformation in Low Carbon Steels

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Deformation-induced ferrite transformation (DIFT) has been proved to be an effective approach to refine ferrite grains. This paper shows that the ferrite grains can further be refined through combination of DIFT and V or VN microalloying. Vanadium dissolved in γ matrix restrains DIFT. During deformation, vanadium carbonitrides rapidly precipitate due to strain-induced precipitation, which causes decrease in vanadium dissolved in matrix and indirectly accelerates DIFT. Under heavy deformation, deformation induced ferrite (DIF) grains in V microalloyed steel were finer than those in V free steel. The more V added to steel, the finer DIF grains obtained. Moreover, the addition of N to V microalloyed steels can remarkably accelerate precipitation of V,and then promote DIFT. However, DIF grains in V-N microalloyed steel easily coarsen.

  1. Effect of the heat-affected zones on hydrogen permeation and embrittlement of low-carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    Razzini, G.; Peraldo Bicelli, L. [Politecnico di Milano (Italy). Dipt. di Chimica Fisica Applicata; Cabrini, M.; Maffi, S.; Mussati, G.

    1998-12-31

    Steels with yield strengths below about 900 MPa are essentially immune to hydrogen embrittlement, and almost all pipeline steels have a yield strength below that value. However, same catastrophic failures of pipelines have been reported. Under mechanical stress these failures are due to the local formation of high-hardness martensite (hard spot) during cooling and from the presence of absorbed hydrogen developed under cathodic over-protection. This paper describes a photoelectrochemical, micrographic and fractographic study of the effect of an heat-affected zone (hard spot) on hydrogen permeation and the embrittlement of an API 5L STD X60 steel. (orig.) 6 refs.

  2. 低碳钢的点蚀诱发敏感性研究%A comparison of pitting susceptibility in low carbon steels

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Three low carbon steels with different metallurgy factors have been selected. Their susceptibility to pitting has been compared by means of polarization test, and pitting characteristics of different inclusions during pitting initiation have been studied with the EPMA, and their passivation films stabilization has been compared by means of Flade measurement. The results show that the susceptibility of boiling steel to pitting initiation is markedly lower than those of killed steel, the pitting susceptibility of killed steel treated by rare earth is between boiling steel and killed steel. The inclusions are the most source susceptible to pitting initiation. Passivation film of boundary between steel matrix and inclusions is the weakest, and the early pitting corrosion is caused from here. The difference of susceptibility of pitting initiated by homogeneous inclusions is large when these inclusions existed in different kind of steels. The difference of susceptibility to pitting initiated by different inclusions in the same steel is small, and the sulfide inclusions have bigger ability in initiating pitting than other types of inclusions.%选择3种冶金因素有代表性的低碳钢,通过极化试验比较了它们之间的点蚀诱发敏感性,同时利用电子探针分析了不同夹杂物在诱发点蚀过程中的腐蚀特征,并利用Flade电位比较了不同钢之间的钝化膜稳定性的差异.结果表明:沸腾钢的点蚀诱发敏感性显著低于镇静钢,稀土处理镇静钢则介于两者之间;夹杂物是钢中主要点蚀诱发源,钢基体与夹杂物交界处的钝化膜保护作用最弱,点蚀均从该处诱发;同类夹杂物在不同类型钢中的点蚀诱发敏感性差异较大,同一钢中的不同类型夹杂物的点蚀诱发敏感性差异很小,硫化物夹杂较其它夹杂物的点蚀诱发敏感性稍强.

  3. Electrochemical and quantum chemical studies of N,N'-bis(4-hydroxybenzaldehyde)-2,2-dimethylpropandiimine Schiff base as corrosion inhibitor for low carbon steel in HCl solution.

    Science.gov (United States)

    Jafari, Hojat; Danaee, Iman; Eskandari, Hadi; Rashvandavei, Mehdi

    2013-01-01

    A synthesized Schiff base N,N'-bis(4-hydroxybenzaldehyde)-2,2-dimethylpropandiimine (p-HBDP) was studied as green inhibitor for the corrosion of low carbon steel in 1 M HCl solution using electrochemical, surface and quantum chemical methods. Results showed that the inhibition occurs through the adsorption of the inhibitor molecules on the metal surface. The inhibition efficiency was found to increase with increasing inhibitor concentration and de-creased with increasing temper-ature, which is due to the fact that the rate of corrosion of steel is higher than the rate of adsorption. Thermodynamic parameters for adsorp-tion and activation processes were determined. Polarization data indicated that this compound act as mixed-type inhibitors and the adsorption isotherm basically obeys the Langmuir adsorption isotherm. The calculations of reactivity indices of p-HBDP such as softness and natural charge distributions together with local reactivity by means of Fukui indices were used to explain the electron transfer mechanism between the p-HBDP molecules and the steel surface.

  4. Effect of cooling rate after hot rolling and of multistage strain aging on the drawability of low-carbon-steel wire rod

    Science.gov (United States)

    Taheri, A. Karimi; Maccagno, T. M.; Jonas, J. J.

    1995-05-01

    Tensile testing was used to simulate the multistage strain aging occurring in low-C steel during the relatively short intervals between dies in a multiple-die wire-drawing machine. The effects were examined of three simulated post-hot-rolling cooling rates and three thermal treatments on the strain-aging susceptibility of a high- and a low-N steel. This was measured by applying a 6 pct tensile strain, followed by aging at either 65° or 100 °C for 20 seconds, and then pulling the specimen to failure at room temperature. Increases in flow stress and decreases in the elongation to fracture both indicated high susceptibility to strain aging. It was found that the nitrogen content, the cooling rate from the hot-rolling temperature to about 300 °C, as well as the cooling rate below 300 °C, all have dramatic effects on the strain-aging behavior. Moreover, multistage strain aging is more severe than single-stage strain aging. The implications of these observations on increasing the drawability of low-carbon-steel wire are discussed.

  5. Relationship Between Solidification Microstructure and Hot Cracking Susceptibility for Continuous Casting of Low-Carbon and High-Strength Low-Alloyed Steels: A Phase-Field Study

    Science.gov (United States)

    Böttger, B.; Apel, M.; Santillana, B.; Eskin, D. G.

    2013-08-01

    Hot cracking is one of the major defects in continuous casting of steels, frequently limiting the productivity. To understand the factors leading to this defect, microstructure formation is simulated for a low-carbon and two high-strength low-alloyed steels. 2D simulation of the initial stage of solidification is performed in a moving slice of the slab using proprietary multiphase-field software and taking into account all elements which are expected to have a relevant effect on the mechanical properties and structure formation during solidification. To account for the correct thermodynamic and kinetic properties of the multicomponent alloy grades, the simulation software is online coupled to commercial thermodynamic and mobility databases. A moving-frame boundary condition allows traveling through the entire solidification history starting from the slab surface, and tracking the morphology changes during growth of the shell. From the simulation results, significant microstructure differences between the steel grades are quantitatively evaluated and correlated with their hot cracking behavior according to the Rappaz-Drezet-Gremaud (RDG) hot cracking criterion. The possible role of the microalloying elements in hot cracking, in particular of traces of Ti, is analyzed. With the assumption that TiN precipitates trigger coalescence of the primary dendrites, quantitative evaluation of the critical strain rates leads to a full agreement with the observed hot cracking behavior.

  6. Structure Character of M-A Constituent in CGHAZ of New Ultra-Low Carbon Bainitic Steel under Laser Welding Conditions

    Institute of Scientific and Technical Information of China (English)

    Lin ZHAO; Wuzhu CHEN; Xudong ZHANG; Jiguo SHAN

    2006-01-01

    800 MPa grade new ultra-low carbon bainitic (NULCB) steel is the recently developed new generation steel.The microstructure in the coarse-grained heat-affected zone (CGHAZ) of NULCB steel under laser welding conditions was investigated by thermal simulation. The influence of the cooling time from 800℃ to 500℃,t8/5 (0.3~30 s), on the microstructure of the CGHAZ was discussed. The experimental results indicate that the microstructure of the CGHAZ is only the granular bainite which consists of bainitic ferrite (BF) lath and M-A constituent while t8/5 is 0.3~30 s. The M-A constituent consists of twinned martensite and residual austenite, and the change of the volume fraction of the residual austenite in the M-A constituent is very small when t8/5 is between 0.3 and 30 s. The morphology of the M-A constituent obviously changes with the variation of t8/5. As t8/5 increases, the average width, gross and shape parameter of the M-A constituent increase, while the line density of the M-A constituent decreases.

  7. Modeling of primary dendrite arm spacing variations in thin-slab casting of low carbon and low alloy steels

    Science.gov (United States)

    Mehrara, H.; Santillana, B.; Eskin, D. G.; Boom, R.; Katgerman, L.; Abbel, G.

    2012-01-01

    Solidification structure of a High Strength Low Alloy (HSLA) steel, in terms of dendrite arm spacing distribution across the shell thickness, is studied in a breakout shell from a thin-slab caster at Tata Steel in IJmuiden. Columnar dendrites were found to be the predominant morphology throughout the shell with size variations across the shell thickness. Primary Dendrite Arm Spacing (PDAS) increases by increasing the distance from meniscus or slab surface. Subsequently, a model is proposed to describe the variation of the PDAS with the shell thickness (the distance from slab surface) under solidifiction conditions experienced in the primary cooling zone of thin-slab casting. The proposed relationship related the PDAS to the shell thickness and, hence, can be used as a tool for predicting solidifcation structure and optimizing the thin-slab casting of low alloy steels.

  8. Tribocorrosion of low carbon steel C15E IN 5% NaCl and 5% NaCl + SiO2

    Directory of Open Access Journals (Sweden)

    S. Aračić

    2010-04-01

    Full Text Available The article represents testing results of corrosion and erosion-corrosion wear. Specimens have been made from low carbon steel C15E in four different states: delivery state and heat-treated (carburizing, boronising and carburizing + boronising. The results are shown as wear of materials (losing of surface mass in mg/(cm2 • d. Surface hardness method HV1 and micro hardness per section of specimen HV0,2 method have been used during the analyses. A comparison of testing results of wear in four different states was made. The best performances have shown samples which have been treated with duplex procedure (carburizing + boronising as was predicted.

  9. Superplasticity of low carbon HSLA steel during bainite transformation. Teitanso teigokinko no beinaito hentai ni okeru chososei kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, H.; Yamamoto, S.; Miyaji, H.; Furubayashi, E. (National Research Inst. for Metals, Tsukuba, Ibaraki (Japan))

    1993-12-01

    Recently, the development of high strength low alloy steel (HSLA steel) of untempered type is advanced by using the comparatively high strength and excellent tenacity of the bainite or martensite of carbon remained being transformed. In the present researches, the superplasticity during the bainite transformation due to the continuous cooling and changes of the structure as well as the mechanical properties due to the superplastic deformation are examined with the samples of Mn-Cr-Mo system HSLA steel. The results obtained therefrom are shown as follows. The temperatre range of B[sub S] and bainite transformation is moving to the higher temperature side along with the increasing of the applied stress when it is over 60 MPa. The bainitic structure is composed of the mixture lath-like bainitic ferrite and granular bainitic ferrite in the use of having no applied stress, while the percentage of the latter increases simultaneously with the increasing of the applied stress. Transformation superplastic strain is increasing together with the increasing of the applied stress, and its increasing is over the linear function when the applied stress is above about 50 MPa. 22 refs., 9 figs., 2 tabs.

  10. Effect of Mg Addition on Inhibiting Austenite Grain Growth in Heat Affected Zones of Ti-Bearing Low Carbon Steels%Effect of Mg Addition on Inhibiting Austenite Grain Growth in Heat Affected Zones of Ti-Bearing Low Carbon Steels

    Institute of Scientific and Technical Information of China (English)

    ZHU Kai; YANG Jian; WANG Rui-zhi; YANG Zhen-guo

    2011-01-01

    To study the effect of Mg addition on inhibiting weld heat affected zones (HAZ) austenite grain growth of Ti-bearing low carbon steels, two steels with and without Mg treated were prepared using a laboratory vacuum. The welding testing was simulated by Gleeble 3500 thermomechanical simulator. The performance of HAZ was investiga ted that the toughness was improved from 3.3 to 185 J by adding 0. 005%Mg (in mass percent) to the steel, and the fracture mechanism changed from cleavage fracture to toughness fracture. Through in-situ observation by a confocal scanning laser microscope, a significant result was found that the austenite grain of the steel with Mg treated was still keeping fine-grained structure after holding at 1 400℃ and lasting for 300 s. This inhibition of austenite grain growth was mainly attributed to the formation of pinning particles after the addition of Mg. The obtained results pro pose a potential method for improving HAZ toughness of structure steels.

  11. A Physical Model to Study the Effects of Nozzle Design on Dense Two-Phase Flows in a Slab Mold Casting Ultra-Low Carbon Steels

    Science.gov (United States)

    Salazar-Campoy, María M.; Morales, R. D.; Nájera-Bastida, A.; Cedillo-Hernández, Valentín; Delgado-Pureco, J. C.

    2017-01-01

    Momentum transfer of argon-steel flows in a slab mold were studied through an air-water physical model and particle image velocimetry measurements under the effects of nozzle design (nozzles with square ports S, square ports with bottom design U and circular ports C) and gas flow rate. The ratio of drag momentum of the gas phase over the liquid phase defines the conditions for coupled (existence of momentum transfer between the phases) and channeled flows (defined as those conditions where there is not further momentum transfer between both phases). When the ratio of superficial velocities of the gas phase over the liquid phase in the nozzle bore is less than 0.14, the flow pattern in the mold is dependent on the nozzle design and flow rate of gas (2 to 10 L/minute). Above this magnitude, the flow pattern becomes uncoupled and independent from the nozzle design and from the flow rate of gas. The ratios of drag velocities of the gas phase on the liquid phase and their superficial velocities in the nozzle bore are strongly dependent on the volume fraction of the gas phase. Nozzle U delivers the smallest sizes of bubbles and the smaller amount of bubble swarms per unit time impacting on the narrow face of the mold. It is, therefore, the most recommendable to cast ultra-low carbon steels. Practical implications derived from these results are written down in the text.

  12. Structure–mechanical property relationship in a high strength low carbon alloy steel processed by two-step intercritical annealing and intercritical tempering

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, W.H. [School of Materials Science and Engineering, University of Science and Technology, Beijing (China); Laboratory for Excellence in Advanced Steel Research, Center for Structural and Functional Materials, Institute for Material Research and Innovation, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70503 (United States); Wang, X.L. [School of Materials Science and Engineering, University of Science and Technology, Beijing (China); Venkatsurya, P.K.C. [Laboratory for Excellence in Advanced Steel Research, Center for Structural and Functional Materials, Institute for Material Research and Innovation, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70503 (United States); Guo, H. [School of Materials Science and Engineering, University of Science and Technology, Beijing (China); Shang, C.J., E-mail: cjshang@ustb.edu.cn [School of Materials Science and Engineering, University of Science and Technology, Beijing (China); Misra, R.D.K. [Laboratory for Excellence in Advanced Steel Research, Center for Structural and Functional Materials, Institute for Material Research and Innovation, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70503 (United States)

    2014-06-01

    The influence of annealing and tempering temperature on the microstructure and mechanical properties was investigated in a low carbon alloy steel that was processed by a two-step intercritical annealing and intercritical tempering heat treatment. In general, the microstructure of the processed steel comprises intercritical lath-like ferrite, bainitic/martensitic lath and acicular-type retained austenite. The lower intercritical annealing temperature resulted in lower fraction of intercritical ferrite with finer grain size and consequently higher strength. On the other hand, the intercritical tempering temperature significantly influenced retained austenite content and precipitation. High fraction of retained austenite was obtained at a temperature slightly above Ac{sub 1} temperature and retained austenite content decreased with increase in tempering temperature. This behavior is attributed to the competition between the enrichment of Mn and Ni and the fraction of reversed austenite. Fine niobium carbide precipitates of size ∼2–6 nm and copper precipitates of size range ∼10–30 nm were obtained. The optimal intercritical annealing and tempering temperatures to obtain the product of tensile strength and elongation % of ∼30 GPa% were 780 °C and 660 °C, respectively and the volume fraction of retained austenite was ∼29%.

  13. Extending the boundaries of mechanical properties of Ti-Nb low-carbon steel via combination of ultrafast cooling and deformation during austenite-to-ferrite transformation

    Science.gov (United States)

    Deng, Xiangtao; Fu, Tianliang; Wang, Zhaodong; Liu, Guohuai; Wang, Guodong; Misra, R. D. K.

    2017-01-01

    We underscore here a novel approach to extend the boundaries of mechanical properties of Ti-Nb low-carbon steel via combination of ultrafast cooling and deformation during austenite-to-ferrite transformation. The proposed approach yields a refined microstructure and high density nano-sized precipitates, with consequent increase in strength. Steels subjected to ultra-fast cooling during austenite-to-ferrite transformation led to 145 MPa increase in yield strength, while the small deformation after ultra-fast cooling process led to increase in strength of 275 MPa. The ultra-fast cooling refined the ferrite and pearlite constituents and enabled uniform dispersion, while the deformation after ultra-fast cooling promoted precipitation and broke the lamellar pearlite to spherical cementite and long thin strips of FexC. The contribution of nano-sized precipitates to yield strength was estimated to be 247.9 MPa and 358.3 MPa for ultrafast cooling and deformation plus ultrafast cooling processes. The nano precipitates carbides were identified to be (Ti, Nb)C and had a NaCl-type crystal structure, and obeyed the Baker-Nutting orientation relationship with the ferrite matrix.

  14. 316L 超低碳不锈钢的焊接性分析%Analysis of the Welding Character of Extra Low Carbon Stainless Steel 316L

    Institute of Scientific and Technical Information of China (English)

    王敏华; 顾天杰

    2015-01-01

    用不同焊接方式和同一焊接方式不同焊口坡度焊接多种316L超低碳不锈钢焊接试板。通过外观观察、 X射线检验、机械性能检验等方法对成品进行分析,掌握了316L材料的焊接性能。结果表明通过采取适当的工艺措施,316L奥氏体不锈钢焊接接头可以避免热裂纹、晶间腐蚀、刀状腐蚀等缺陷。同时验证了316L焊接接头良好的耐蚀性和机械性能。%A variety of extra low carbon stainless steel 316 L welding test plates were made by different welding ways and different weld slope in the same way.Through visual observation, X-ray inspection, mechanical properties test to analyze the products, the welding properties of 316L materials were mastered.The results showed that by adopting the appropriate process measures, welding joint of 316L austenitic stainless steel can prevent hot crack, intergranular corrosion, knife shaped corrosion.At the same time, it was verified that 316L welded joints had good corrosion resistance and mechanical properties.

  15. Development of a carburizing and quenching simulation tool: A material model for low carbon steels undergoing phase transformations

    Energy Technology Data Exchange (ETDEWEB)

    Bammann, D.; Prantil, V.; Kumar, A. [Sandia National Labs., Livermore, CA (United States)] [and others

    1996-06-24

    An internal state variable formulation for phase transforming alloy steels is presented. We have illustrated how local transformation plasticity can be accommodated by an appropriate choice for the corresponding internal stress field acting between the phases. The state variable framework compares well with a numerical micromechanical calculation providing a discrete dependence of microscopic plasticity on volume fraction and the stress dependence attributable to a softer parent phase. The multiphase model is used to simulate the stress state of a quenched bar and show qualitative trends in the response when the transformation phenomenon is incorporated on the length scale of a global boundary value problem.

  16. Experimental study on variations in Charpy impact energies of low carbon steel, depending on welding and specimen cutting method

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhaorui; Kang, Hansaem; Lee, Young Seog [Chung-Ang University, Seoul (Korea, Republic of)

    2016-05-15

    This paper presents an experimental study that examines variations of Charpy impact energy of a welded steel plate, depending upon the welding method and the method for obtaining the Charpy specimens. Flux cored arc welding (FCAW) and Gas tungsten arc welding (GTAW) were employed to weld an SA516 Gr. 70 steel plate. The methods of wire cutting and water-jet cutting were adopted to take samples from the welded plate. The samples were machined according to the recommendations of ASTM SEC. II SA370, in order to fit the specimen dimension that the Charpy impact test requires. An X-ray diffraction (XRD) method was used to measure the as-weld residual stress and its redistribution after the samples were cut. The Charpy impact energy of specimens was considerably dependent on the cutting methods and locations in the welded plate where the specimens were taken. The specimens that were cut by water jet followed by FCAW have the greatest resistance-to-fracture (Charpy impact energy). Regardless of which welding method was used, redistributed transverse residual stress becomes compressive when the specimens are prepared using water-jet cutting. Meanwhile, redistributed transverse residual stress becomes tensile when the specimens are prepared using wire cutting.

  17. Characterization and Properties of Nanostructured Surface Layer in a Low Carbon Steel Subjected to Surface Mechanical Attrition

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A nanostructured surface layer was synthesized on a Iow carbon steel by using surface mechanical attrition (SMA)technique. The refined microstructure of the surface layer was characterized by means of different techniques,and the hardness variation along the depth was examined. Experimental results show that the microstructure isinhomogeneous along the depth. In the region from top surface to about 40μm deep, the grain size increases fromabout 10 nm to 100 nm. In the adjacent region of about 40~80μm depth, the grain size increases from about 100nm to 1000 nm. The grain refinement can be associated with the activity of dislocations. After the SMA treatment,the hardness of the surface layer is enhanced significantly compared with that of the original sample, which canprimarily be attributed to the grain refinement.

  18. Metallurgical and Corrosion Properties of Explosively Welded Ti6Al4V/Low Carbon Steel Clad

    Institute of Scientific and Technical Information of China (English)

    Nizamettin Kahraman; Beh(c)et Gülen(c)

    2005-01-01

    Titanium alloy (Ti6Al4V) and Iow carbon steel (LCS) were joined by explosive welding method using different ratios of explosive. Some metallurgical properties of joined samples were investigated. Joined samples were examined by means of optical microscope, scanning electron microscope (SEM) and tensile-shearing tests. Bending, tensile, hardness and corrosion behaviour of the samples were investigated. Separation was not occurred on the joining interface after tensile-shearing and bending tests. It is seen that hardness of both plates were increased with increasing explosive.It is found that increasing explosive ratio leads to an increase in corrosion. It is also found that corrosion rate was high at the beginning of the experiment but the rate of the corrosion decreased subsequently during the experiment.

  19. Diffusivity of Al and Fe near the diffusion bonding interface of Fe3Al with low carbon steel

    Indian Academy of Sciences (India)

    Li Yajiang; Wang Juan; Yin Yansheng; Ma Haijun

    2005-02-01

    The distribution of elements near the Fe3Al/Q235 diffusion bonding interface was computed by the diffusion equation as well as measured by means of EPMA. The results indicated close agreement between the two for iron and aluminium. Diffusion coefficient in the interface transition zone is larger than that in the Fe3Al and Q235 steel at the same temperature, which is favourable to elemental diffusion. The diffusion distance near the Fe3Al/Q235 interface increased with increasing heating temperature, , and the holding time, . The relation between the width of the interface transition zone, , and the holding time, , conformed to parabolic growth law: 2 = 4.8 × 104 exp(– 133/RT) ( – 0). The width of the interface transition zone does not increase significantly for holding times beyond 60 min.

  20. Recovery of Ductility in Ultrafine-Grained Low-Carbon Steel Processed Through Equal-Channel Angular Pressing Followed by Cold Rolling and Flash Annealing

    Science.gov (United States)

    Singh, Raj Bahadur; Mukhopadhyay, N. K.; Sastry, G. V. S.; Manna, R.

    2017-01-01

    The low-carbon steel workpieces are deformed by equal-channel angular pressing at 293 K (20 °C) up to an equivalent strain of 12 using route B c, which results in the bulk ultrafine-grained (UFG) structure with high dislocation density and partial dissolution of cementite. The yield strength (YS) is enhanced from 208 (as-received) to 872 MPa and the tensile strength is increased from 362 to 996 MPa, but the material loses total elongation (TE) from 36.2 to 2.9 pct. Cold rolling of equal-channel angular pressed steel produces the refined structure of grain size 0.11 μm. The YS increases further to 924 MPa with a marginal gain in ductility due to the reappearance of the γ fiber component. Flash annealing the samples, which were equal-channel angular pressed followed by cold rolling, at 873 K (600 °C) results in 27 pct of micron-sized (9 µm) ferrite grains in submicron-sized (<1 µm) matrix with a reduced defect density and small amount of precipitation of cementite. TE increases from 2.9 to 23.3 pct. The material retains a YS of 484 MPa and tensile strength of 517 MPa, which are higher than those of the as-received material. The UFG grains are failed by cleavage, but the micron-sized grains display ductile fracture. The ductility of the flash-annealed material is recovered significantly due to bimodal grain size distribution in ferrite and the development of a good amount of γ fiber texture components. The major contribution toward recovery of ductility comes from the bimodal grain size distribution in ferrite rather the precipitation of cementite.

  1. Building A Simulation Model For The Prediction Of Temperature Distribution In Pulsed Laser Spot Welding Of Dissimilar Low Carbon Steel 1020 To Aluminum Alloy 6061

    Science.gov (United States)

    Yousef, Adel K. M.; Taha, Ziad. A.; Shehab, Abeer A.

    2011-01-01

    This paper describes the development of a computer model used to analyze the heat flow during pulsed Nd: YAG laser spot welding of dissimilar metal; low carbon steel (1020) to aluminum alloy (6061). The model is built using ANSYS FLUENT 3.6 software where almost all the environments simulated to be similar to the experimental environments. A simulation analysis was implemented based on conduction heat transfer out of the key hole where no melting occurs. The effect of laser power and pulse duration was studied. Three peak powers 1, 1.66 and 2.5 kW were varied during pulsed laser spot welding (keeping the energy constant), also the effect of two pulse durations 4 and 8 ms (with constant peak power), on the transient temperature distribution and weld pool dimension were predicated using the present simulation. It was found that the present simulation model can give an indication for choosing the suitable laser parameters (i.e. pulse durations, peak power and interaction time required) during pulsed laser spot welding of dissimilar metals.

  2. Texture evolution of 390 MPa grade ultra low carbon bake hardening steel%390MPa级超低碳BH钢织构演变规律

    Institute of Scientific and Technical Information of China (English)

    陈银莉; 苏岚; 赵爱民; 吴雷; 李本海; 刘光明; 滕华湘

    2012-01-01

    Texture evolution in a 390 MPa grade high strength ultra low carbon bake hardening( ULCBH )steel in the process of hot rolling, cold rolling and annealing is studied by utilizing ODF texture analysis method. The effect of cold rolling reduction and annealing parameters on texture is measured. The results show that the ULC-BH sheet steel after cold rolling has a highly preferred orientation with typical /112/ 〈 110 〉 and /lll/ 〈 110 〉 texture, and strong unfavorable deformation texture /001 / 〈 110 〉. The increase of cold rolling reduction influeneed the strength ratio of favorable components to unfavorable components in the annealing textures. After annealing, a very strong y texture was obtained when cold rolling reduction reached 80% , which intensity peak was at 1111 / 〈 112 〉 component with f(g) value of 11.7. The annealing temperature and time had little influence on a texture, while increasing annealing temperature and extending holding time enhanced y texture intensity and r value.%采用ODF织构分析方法,对390MPa级超低碳BH钢板热轧、冷轧、退火过程织构演变规律进行研究,并对不同冷轧月下量和不同退火工艺织构进行分析。结果表明:经冷轧变形后的钢板有较强的择优取向,具有典型的{112}〈110〉和{111}〈110〉织构,形变织构中的不利织构{001}〈110〉较强;冷轧压下率为80%时再结晶退火后钢板具有较强的Y织构,{111}〈112:织构取向密度高达11.7;退火温度和保温时间对a织构影响不大,提高退火温度和延长保温时间使y织构增强,r值增加。

  3. Effect of aluminum content on austenite-ferrite transformation temperature in low carbon (Si-Al hot rolled GNO electrical steels

    Directory of Open Access Journals (Sweden)

    Equihua, F.

    2010-02-01

    Full Text Available The aim of the present study is to investigate the synergistic effect of silicon and aluminum content on the austeniteferrite transformation temperatures on cooling (Ar3, Ar1 in non-oriented (GNO Al-Si-low carbon electrical steel strips. Two specimens with different Al contents: A=0.22 wt% and B=0.61 wt%Al, were analyzed by “in-situ” high temperature X-ray diffraction experiments. The samples were austenitized at 1050 °C for 5 minutes and sequentially cooling in a stepwise manner by steps of 10 °C inside an environmental chamber installed in a Philips X’Pert multi-purpose diffractometer. X-ray diffraction patterns were recorded every 10 °C during cooling from 1000 to 720 °C. The austenite to ferrite transformation temperatures on cooling, Ar3 and Ar1, were estimated from changes in the intensities of the (110-α and (111-γ peaks as a function of temperature. The results of the experiments show that the transformation temperatures increase with increasing aluminum content from 0.22 to 0.61 wt%. In addition, the two-phase field (austenite + ferrite in the system Fe-C decreases with increasing silicon and aluminum contents for these GNO steels. X-Ray diffraction results were supported by microstructural observations of quenched samples of steel B which were subjected to similar heat treatment conditions than those applied in the X-ray diffractometer experiments. Thin ferrite films (~ 4-10 μm were observed in the microstructure of specimens of steel B quenched from temperatures close to the experimental Ar3.

    El objetivo del presente trabajo es investigar el efecto del contenido de aluminio y silicio sobre la temperatura critica de transformación, durante el enfriamiento, en aceros eléctricos de grano no-orientado (GNO de bajo carbono laminados en caliente. Dos muestras, con diferentes contenidos de aluminio: A=0,22 y B=0,61 % en peso, fueron analizadas mediante la técnica in-situ de difracción de rayos X a alta temperatura

  4. Effect of plastic deformation on the structure and mechanical properties of an ultra-low carbon interstitial-free steel in the monolithic material and as a component of a sandwich composite

    Science.gov (United States)

    Gladkovsky, S. V.; Kuteneva, S. V.; Kamantsev, I. S.; Sergeev, S. N.; Safarov, I. M.

    2016-10-01

    The structure and mechanical properties of ultra-low carbon interstitial-free (IF) steel in the annealed state, after warm and cold rolling, and as a component of seven-layer steel-aluminum composite have been studied. A comparative analysis of the results of structural studies using optical microscopy and scanning and transmission electron microscopy have revealed the possibility of the formation of an ultrafinegrained structure in a steel layer during rolling at temperatures ranging from room temperature to 520°C. It has been found that the seven-layer composite has higher strength properties as compared to monolithic samples of the IF steel after analogous regime of the warm rolling.

  5. DIRECTION OF LOW-CARBON TECHNOLOGY R&D OF STEEL INDUSTRY IN DEVELOPED COUNTRIES%发达国家钢铁工业低碳技术研发方向

    Institute of Scientific and Technical Information of China (English)

    张京萍

    2012-01-01

    减少二氧化碳排放是当今世界的热点议题。近年来,国外发达国家的钢铁工业一直将研发和应用突破性的技术作为减排二氧化碳的主要措施。简要叙述了欧盟、日本和美国钢铁工业在低碳技术研发方面的情况,并对我国钢铁工业研发具有自主知识产权的低碳技术提出建议。%Reduction of C02 emissions is a hot topic in today's world. In recent years, the steel industry in developed countries has made R&D of breakthrough technology as the main measure of the reduction of C02 emissions. This article briefly describes the situation of steel industry in the EU, Japan and the U.S. in the R&D of low-carbon technologies, and also suggests that Chinese steel industry should also start R&D of low-carbon technologies with independent intellectual property rights.

  6. Evaluación del empleo de aceros de bajo contenido de carbono en la fabricación del cuerpo de cilindros oleohidráulicos. // Low carbon steel evaluation for oleohydraulic cylinders manufacturing.

    Directory of Open Access Journals (Sweden)

    V. Gómez Rodríguez

    2003-05-01

    Full Text Available En el trabajo se realiza una evaluación del empleo de aceros de bajo contenido de carbono en la fabricación del cuerpo decilindros oleohidráulicos de producción nacional. Se estudia la influencia del cambio de material en la calidad superficial,la resistencia al desgaste y el comportamiento desde el punto de vista de la corrosión.Palabras claves: Cilindros oleohidráulicos, resistencia superficial, corrosión, acero._________________________________________________________________________________Abstract.In this paper, an evaluation of the use of low carbon steel used to manufacture the hydraulic homemade cylinders body iscarried out. The influence of change of material in surface quality, the wear resistance and the behaviour from the corrosionpoint of view, are studied.Key words: Oleohydraulic cylinders, superficial strength, corrosion, steel.

  7. Slag Composition Control in Soft-Killed Process for Ultra-Low Carbon Steel%超低碳钢弱脱氧工艺下炉渣组分的控制

    Institute of Scientific and Technical Information of China (English)

    张国兴; 王谦; 何生平; 曾建华

    2011-01-01

    Based on the soft-killed process for ultra-low carbon steel, the relationship between oxidizability of top slag and oxygen activity in steel was calculated using software Factsage, and then the effect of components of top slag on sulphur distribution ratio was also calculated. The results indicated that for ultra-low carbon steel making,ω(FeO+ MnO) in top slag should be controlled below 15 % at least, and ω(CaO)/ω(Al2O3 ) should be controlled 2.5-4.0. Industrial test showed that after the ω(FeO+ MnO) is controlled below 15% through the slag property changing treatment, the resulfurization can be avoidable, the sulfur content of products is controlled lower than 0.005 %, and the requirements for the steel can be met.%针对采用弱脱氧工艺冶炼超低碳钢,利用Factsage软件计算了顶渣氧化性与钢水氧活度之间的关系,进而计算了炉渣各组元对硫分配比的影响.结果表明,对于超低碳钢的生产,顶渣中w(FeO+MnO)至少应控制在15%以下,w(CaO)/w(A12O3)控制在2.5~4.0.工业试验表明,通过顶渣改性将w(FeO+MnO)控制在15%以下可避免回硫现象的发生,成品硫质量分数小于0.005%,达到了钢种要求.

  8. 低碳中铬钢渗碳层的耐磨粒磨损性能研究%Study on Abrasive Wear-Resistance of Carburized Low-carbon Medium-chromium Steel

    Institute of Scientific and Technical Information of China (English)

    张黔; 孙小华; 李朝志

    2001-01-01

    The microstructure and abrasive wear-resistence of carburized layer of low-carbon medium-chromiun steel.compered with cemented 20 steel and Cr12Mo1V steel,was investigated.Carburized layer of 1Cr6Si2Mo steel contains large number of fine carbide(2.5~3.0 μm),which size smaller than that one of Cr12Mo1V.The wear-resistence of 1Cr6Si2Mo steel after carburizing and queching is obviously better than that of 20 steel.but less than that of Cr12Mo1V steel by vacuum heat treatment.%对低碳中铬钢(1Cr6Si2Mo)固体法稀土渗碳层的组织和耐磨性能与渗碳20钢及淬火Cr12Mo1V钢进行了对比试验研究。1Cr6Si2Mo钢的渗碳层内含有大量粒度为2.5~3.0 μm、弥散分布的铬碳化物,其尺寸比Cr12Mo1V钢中的共晶碳化物小。渗碳淬火后的1Cr6Si2Mo钢试样耐磨粒磨损性能大大优于渗碳淬火后的20钢,但不及真空热处理的Cr12Mo1V。

  9. 外锈层对低碳钢腐蚀影响的电化学分析%Electrochemical Analysis Outer Rust Layer Effect on Corrosion Behavior of Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    田志强; 孔小东; 王崇碧; 王源升

    2012-01-01

    In the long-term corrosion process, the rust layer formed on the low carbon hull steel may affect its corrosion behavior. The influence mechanism of the outer rust layer on the hull steel corrosion behavior is unclear. A certain type of low carbon steel was selected to soaked in 3mass% NaCl solutions for one year, then of which the electrochemical corrosion characteristic was studied by electrochemical methods before and after removal of the formed outer rust layer. The corrosion resistance before and after the removal of the outer rust layer was compared, and the effect of the outer rust layer on the corrosion of the rust steel was analyzed by use of linear polarization, AC impedance spectroscopy (EIS) and electrochemical noise (EN). The morphology, phase constituents and elemental distribution of the corrosion products formed on the rust and base steels were characterized by EPMA and XRD respectively, then the relevant corrosion mechanism was discassed. The results show that, the corrosion resistance of the steel decreased and the corrosion rate increased after removal of outer rust layer; the removal of the outer rust layer may facilitate the oxygen inward-transportation thereby affecting the electrode process on interface of the rust layer/ metal matrix.%选用某型船用低碳钢,在3mass%NaCl溶液中浸泡一年,用电化学技术研究外锈层去除前后低碳钢的腐蚀电化学特征.运用线性极化、电化学阻抗(EIS)和电化学噪声(EN)技术比较外锈层去除前后钢的耐蚀性,分析外锈层对腐蚀的影响;通过对内、外锈层和裸钢腐蚀形貌的显微观察、对内锈层的电子探针(EMPA)和x射线衍射(XRD)分析,研究外锈层对腐蚀影响的机理.结果表明,去除外锈层使钢的耐蚀性减小,腐蚀速率增大;外锈层的去除导致氧更易于向内输送,进而影响内锈层/金属基体界面的电极过程.

  10. Effect of boron on continuous cooling transformation of low carbon steel%硼对低碳钢变形后连续冷却转变的影响

    Institute of Scientific and Technical Information of China (English)

    杨静; 郭晓波; 李桂艳; 赵宝纯

    2012-01-01

    The continuous cooling transformation curves of the B-bearing and B-free low carbon steel were measured by means of Vickers-hardness measurement and thermal dilation method by use of Gleeble-3800 thermo-simulation machine.The microstructure was observed and analyzed by OM and SEM.The results show that when the cooling rates are changed in a large range,full bainite can be obtained in the tested steel with boron addition,compared with which the full bainite can not be obtained in the tested steel without boron.The lath bainte can be obtained in the steel with boron addition when the cooling rate is greater than 5 ℃/s.While there is no such structure that can be observed in the steel without boron.Compared with that of the steel without boron,the hardness of the steel with boron addition is much higher under the same process and the difference between the hardness of the two steels become obvious with the increment of the cooling rate.%利用Gleeble-3800热模拟试验机,采用热膨胀法结合硬度测试研究了含硼和不含硼两种低碳钢的连续冷却转变过程,通过光学显微镜、扫描电镜分析了不同冷速下两种钢的组织转变。结果表明,不含硼钢未得到全部贝氏体组织,含硼钢可在相当大的冷速范围内得到全部贝氏体组织,且可细化显微组织;含硼钢中冷速大于5℃/s时出现板条贝氏体,而不含硼钢在整个试验冷速范围内均无板条贝氏体出现;含硼钢的硬度明显高于不含硼钢相同冷速下的硬度值,且随着冷却速度的增加相同冷速下含硼钢与无硼钢硬度值的差明显变大。

  11. Innovative Thinking of the Development of China's Steel Industry in the Era of Low - Carbon Economy%低碳经济时代我国钢铁行业发展的创新思考

    Institute of Scientific and Technical Information of China (English)

    马素敏

    2011-01-01

    随着低碳经济时代的到来,企业面临更加严峻的竞争环境,对企业发展提出了新的发展要求,通过分析企业在新形势下所面临的机遇与挑战,以及企业内部优劣势,结合实际案例分析钢铁企业目前面临的新环境并做出对策研究.%In the era of low - carbon economy, enterprises have to face more severe competition. Through the analysis of opportunities and challenges enterprises have to face, and internal strengths and weaknesses of enterprises in the new situation, combined with practical ease, the paper studies the current situation of steel industry and makes countermeasures accordingly.

  12. Comparison of CaCO3 from Natural Sources and Artificial Carbonates as Activators of Solid-Phase Carburizing of Low-Carbon Steel

    Science.gov (United States)

    González-Angeles, A.; López-Cuevas, J.; Pitalúa-Díaz, N.

    2013-11-01

    The process of solid-phase carburizing of steel with the use of carbonates of different origin including chemical reagents, limestone and oyster shells is studied. The highest microhardness is obtained in the case of SrCO3, wheres Na2CO3 is shown to be the cheapest and most economically expedient carbonate. A good carburized layer can be obtained using a mixture of limestone and oyster shells.

  13. 超低碳钢RH冶炼脱碳过程的数学模型%Mathematical model of decarburization processes in RH refining for ultra-low carbon steel

    Institute of Scientific and Technical Information of China (English)

    赵新宇; 张炯明; 罗衍昭; 肖超; 吴炼

    2012-01-01

    In consideration of the equilibrium of C and 0 elements, a mathematical model was established for decarburization in RH refining. The principle and process of establishing the model were illustrated according to 210 t RH refining for ultra-low carbon steel. A comparison between the modeling results and measuring data shows that the prediction of the mathematical model agrees well with industrial practice. There exists the nonuniform characteristic of carbon in liquid steel. The position with the minimum mass fraction of carbon is at the free surface in the vacuum chamber above the descending snorkel, while the position with the maximum mass fraction of carbon is at the interface between slag and liquid steel on the right side of the ascending snorkel. The difference between the maximum and minimum values is 0. 0025% after 20 min circulating.%在充分考虑RH平衡碳氧浓度的前提下,建立脱碳反应数学模型.以210t超低碳钢RH冶炼工艺为背景,详细给出数学模型的建立原则与过程.将模拟结果与实际测量数据进行对比发现,数学模型与实际测量数据有很好的吻合度.碳元素在钢液内存在一定的不均匀性,真空室自由液面下降管上方碳元素质量分数最小,钢渣界面处上升管右侧碳元素质量分数最大,循环20min后,二者相差0.0025%左右.

  14. 低碳钢固体渗碳的实验与研究%Experiment and Research on Solid-carburizing for Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    廖西平

    2012-01-01

    The experiment of solid-carburizing process on 20 steel and 20CrMoV steel has been fully developed, which includes preparatory heat-treatment, carburizing craft, metallographic structure, the final heat- treatment, etc. This experiment analyzed the factors of carburizing coating and hardness, and the basic law and technology of solid- carburizing process have been worked out. The experiment has proved that solid- carburizing craft has several advantages such as simple process, easily to operate and control, low cost, and without special devices. The solid- carburizing product completely meets conventional requirement. However, solid-carburizing process has its disadvantages such as thin carburizing coating and too long total operating time, thus solid- carburizing only fits for the production of single-piece on small scale.%对20、20CrMoV钢的固体渗碳进行了较全面的实验及研究,包括钢的预备热处理、渗碳工艺、金相组织、最终热处理等;分析了渗碳层、硬度的影响因素,并总结摸索出固体渗碳的基本规律和工艺技术;实验证明:固体渗碳工艺简单、操作简单、成本低廉,不需要专门设备;渗碳件在性能上完全能够达到常规渗碳的要求,但固体渗碳的渗碳层偏薄,时间较长,只能适应单件、小批量的生产。

  15. Weldability of Low Carbon and High Niobium X80 Pipeline Steel and Its Engineering Practice%低碳高铌X80管线钢焊接性及工程实践

    Institute of Scientific and Technical Information of China (English)

    尚成嘉; 王晓香; 刘清友; 付俊岩

    2012-01-01

    Low carbon high Nb and high Mn microalloying design has been applied to X80 pipeline steel , the longitudinal and submerged arc weling performance of X80 line pipe are of prime importance to application of the said alloy system. The results of thermal simulation study showed that the optimum heat input energy for alloy system X80 steel should be lower than 30 kj/cm. The grain size of CGHAZ of high Nb pipeline steel is smaller than that of common Nb steel; the coarse precipitates do not appear in ICCGHAZ, and the size of Nb(CN) is not more than 30nm. A large number of production data indicated that the mechanical properties of HAZ in high Nb X80 pipeline steel, especially the toughness, can reach high level, which can fully meet the requirements of the Second West-east Gas Pipeline Project The application of this alloy system provided the Second West-east Gas Pipeline Project with powerful safeguard.%低C高Nb高Mn的合金设计已广泛应用于X80管线钢,X80管线钢钢管的直缝焊接以及螺旋缝焊接性能对该合金体系的应用极其重要.热模拟研究结果表明,该合金体系X80管线钢的最佳热输入量应低于30 kJ/cm.相比于普通Nb含量管线钢,高Nb含量设计管线钢的粗晶区(CGHAZ)晶粒尺寸更细;临界粗晶区(ICCGHAZ)并没有粗大的析出物,Nb(CN)的尺寸≤30 nm.直缝焊及螺旋焊X80钢管的大量工业生产数据表明,高Nb X80管线钢热影响区的力学性能,特别是韧性能达到较高的水平,完全满足西气东输二线的技术指标,该合金体系的应用为西气东输二线的成功建成提供了有力保障.

  16. 低碳Q690qENH高强桥梁钢的动态再结晶行为%Dynamic Recrystallization Behaviors of Low Carbon Q690qENH High-strength Bridge Steels

    Institute of Scientific and Technical Information of China (English)

    陈俊; 唐帅; 周砚磊; 刘振宇; 王国栋; 杨颖; 陈军平

    2012-01-01

    对低碳Q690qENH高强桥梁钢进行压缩实验,研究了动态再结晶行为.结果表明,在低碳Q690qENH高强桥梁钢的轧制热变形过程中,其软化以动态回复为主,只在0.1s^-1和0.2s^-1低应变速率下才发生明显的动态再结晶.通过计算将应力因子a修正为0.0099MPa^-1,得到了实验钢的动态再结晶激活能,建立了动态再结晶动力学模型。采用P-M-K法确定了εc/εp约为0.72,且峰值应变与Z/A满足幂函数关系,建立了动态再结晶临界应变模型,其计算值与热变形中的显微组织演变规律一致。研究了温度对动态再结晶过程中界面迁移速率的影响规律。%The dynamic recrystallization behaviors of low carbon Q690qENH high-strength bridge steel were investigated by hot compression deformation using MMS-300 thermo-simulation machine. The results show the softening of low carbon Q690qENH high-strength bridge steel is mainly controlled by dynamic recovery during hot rolling deformation and the dynamic recrystallization occurs obviously at low strain rates of 0.1 s^-1 and 0.2 s^-1. The stress factor was modified as 0.0099 MPa-1, the dynamic recrystal- lization activation energies were gained, and the dynamic recrystallization kinetics model was established. The expression of εc=0.72εp was determined using P-M-K method. Correlations between peak strain and Z/A are power function, and dynamic recrystallization critical strain model was established calculation values of which are good agreement with evolution of microstructure during hot deformation. EfFects of temperature on migration-rate of interface were also investigated during dynamic recrystallization.

  17. The influence of Desulfovibrio vulgaris on the efficiency of imidazoline as a corrosion inhibitor on low-carbon steel in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Rodriguez, Carlos A. [Facultad de Quimica UNAM, Ciudad Universitaria, C.P. 04510 Mexico, D.F. (Mexico)], E-mail: gorc74@yahoo.com; Rodriguez-Gomez, Francisco J.; Genesca-Llongueras, Joan [Facultad de Quimica UNAM, Ciudad Universitaria, C.P. 04510 Mexico, D.F. (Mexico)

    2008-12-01

    The action of Desulfovibrio vulgaris (Dv) during a corrosion process has been reported in literature, but the influence of imidazoline in the formation of biofilms is not clear, as well as the effect of bacteria on the efficiency of the corrosion inhibitors. The aim of this work is to determine the behavior of bacteria in the presence of imidazoline. Therefore, the growth of Dv, isolated and characterized from a morphological point of view, was monitored during 21 days, during which synthetic seawater was used as the culture medium, according to the ASTM D665-98 standard. Electrochemical noise (EN) was employed to establish the corrosion type generated by the microorganism on an AISI 1018 steel cylinder. The attack was observed using scanning electron microscopy (SEM). In order to evaluate the efficiency of the corrosion inhibitor, Tafel extrapolation was used; the optimum concentration of the inhibitor was used in the presence of sulphate-reducing bacteria (SRB). In general, two forms of corrosion were observed: localized corrosion (in the LAG phase) and mixed corrosion (in the LOG phase)

  18. Characterisation of passive films formed on low carbon steel in borate buffer solution (pH 9.2) by electrochemical impedance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hamadou, L. [Laboratoire de Materiaux, Electrochimie et Corrosion, Universite Mouloud MAMMERI de, Tizi-Ouzou, B.P. 17 (15000) (Algeria)]. E-mail: lamhama@yahoo.fr; Kadri, A. [Laboratoire de Materiaux, Electrochimie et Corrosion, Universite Mouloud MAMMERI de, Tizi-Ouzou, B.P. 17 (15000) (Algeria); Benbrahim, N. [Laboratoire de Materiaux, Electrochimie et Corrosion, Universite Mouloud MAMMERI de, Tizi-Ouzou, B.P. 17 (15000) (Algeria)

    2005-12-15

    The comprehension of passivity and its protective character against corrosion is closely connected with the electronic properties of passive films. Passive films formed anodically on carbon steel in borate/boric acid solution, pH 9.2, have been characterised by electrochemical impedance spectroscopy (EIS). Mott-Schottky plots and impedance measurements were made on films formed at different potentials and times. The investigation allowed the determination of the semiconductive properties of the films. The results of the capacitance response indicate that the passive films behave like highly doped n-type semiconductors, showing that the passive film properties are dominated by iron. The value of donors density (N {sub D}) for the passive film is of the order of 10{sup 21} cm{sup -3} and decreases with increasing formation time and potential, indicating that defects decrease with increasing film thickness. Based on the information about the physical phenomena, an equivalent circuit is proposed to fit the experimental data, leading to determination of anodic film capacitance and film resistance.

  19. Fluxes design for continuous casting mold of slab low carbon steels; Diseno de polvos de molde para colada continua de slabs de aceros bajo carbono

    Energy Technology Data Exchange (ETDEWEB)

    Cruz-Ramirez, A.; Chavez-Alcala, J. F.; Romero-Serrano, J. A.

    2004-07-01

    Commercial fluxes were characterized by laboratory tests, and their original properties were changed with additions of chemical reagents in order to establish criteria and design strategies to produce new fluxes. The characterization of the commercial fluxes reveals that they are produced by simple mechanical blend of minerals, using feldspars and clays as base materials, containing SiO{sub 2} Al{sub 2}O{sub 3}, Na{sub 2}O and in less quantity K{sub 2}O, Fe{sub 2}O{sub 3} and MnO; limestone as the main source of CaO, fluorspar (CaF{sub 2}) used to control the viscosity and graphite as carbon source. Melting-solidification tests revealed melting and fluidity temperatures and the existence of abundant mineralogical phases formed during the flux solidification. some important mineralogical compounds are the nepheline (NaAlSiO{sub 4}) and cus pidine (Ca{sub 4}Si{sub 2}O{sub 7}F{sub 2}): these species have a direct influence on the heat transfer phenomena from strand to mold and therefore on the phase transformations and the shrinkage of the steel. (Author) 8 refs.

  20. Effects of heating and cooling rate on transformation behaviors in weld heat affected zone of low carbon steel; Teitanso koban no yosetsu netsu eikyobu no hentai kyodo ni oyobosu kanetsu reikyaku sokudo no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kanetsuki, Y.; Katsumata, M. [Kobe Steel, Ltd., Kobe (Japan)

    1998-01-25

    Discussions were given on effects of welding heat cycles on transformation behaviors in a weld heat affected zone (HAZ). Test pieces are low-carbon fine ferrite pearlite organization steel sheets, which have been treated with a thermomechanical control process (TMCP). The heat cycling was experimented at a maximum temperature of 1350 degC by using a high-frequency heating coil, heating rates from 0.15 to 200 degC/s, cooling rates from 10 to 80 degC/s at an elevated temperature region (higher than 900 degC), and transformation regions (lower than 900 degC) from 0.5 to 6 degC. A transformation curve in actual welding heat cycling was interpreted from these results. Shear-type inverse transformation (from ferrite to austenite) occurs in a rate region corresponding to the heating rate realized during welding. Austenite containing internal stress and a lower structure formed by this inverse transformation accelerates transformation into grain boundary ferrite (GBF) and acerous ferrite (AF). On the other hand, slow cooling in the elevated temperature region releases the internal stress, restores the lower structure, and suppresses the GBF and AF transformation. The GBF tends to precipitate pearlite in adjacent regions and deteriorates the HAZ tenacity. 17 refs., 8 figs., 1 tab.

  1. Ti+Nb和Ti+V超低碳烘烤硬化钢的组织和性能研究%Research on Microstructure and Mechanical Properties of Ti+Nb and Ti+V Ultra-low Carbon Bake Hardening Steels

    Institute of Scientific and Technical Information of China (English)

    陈继平; 钱健清; 李胜祗; 康永林

    2012-01-01

    Deformation resistance and dynamic continuous cooling transformation of Ti+Nb and Ti+V bearing ultra-low carbon bake hardening steels were studied using Gleeble-1500 thermal simulator. The microstructures of two experimental steels under different cooling conditions were also analyzed. The results showed that the deformation resistance of Ti+Nb bearing ultra-low carbon bake harden-ing steel was 13MPa higher than that of Ti +V bearing ultra-low carbon bake hardening steel at 1100°C with the strain rate of ls~'. The morphology of the microstructures and the grain size have big difference for two experimental steels under the same deformation conditions. The room temperature microstructures of the two experimental steels are polygonal ferrites under various cooling conditions. The ferrites of Ti + Nb bearing ultra-low carbon bake hardening steel are finer and have irregular shape with the average grain size of 16μm, while for Ti + V bearing ultra-low carbon bake hardening steel, the ferrites are coarse and have regular shape with the average grain size of 26μm.%采用Gleeble-1500热模拟试验机对Ti+Nb和Ti+V复合处理超低碳BH钢的变形抗力和动态连续冷却转变进行研究,并观察了两种实验钢在不同冷却工艺条件下的金相组织.结果表明:在1100℃、应变速率ls-1时Ti+ Nb超低碳BH钢的变形抗力比Ti+V超低碳BH钢高出约13MPa,在相同的变形条件下,两种实验钢的组织形貌及晶粒尺寸差别较大.两种超低碳BH钢在不同冷却条件下的室温金相组织均是多边形的铁素体,Ti+Nb超低碳BH钢铁索体晶粒较为细小,形状不规则,平均晶粒尺寸为16μm,Ti+V超低碳BH钢铁素体晶粒则较为粗大,形状规则,平均晶粒尺寸为26μm.

  2. Continuous Cooling Transformation Behavior and Microstructure of Low Carbon Nb-Bearing Microalloyed Steel%低碳含铌微合金钢的连续冷却相变行为及显微组织

    Institute of Scientific and Technical Information of China (English)

    宗云; 赵莉萍; 麻永林; 王宝峰; 宋海彬

    2011-01-01

    利用Gleeble-1500D型热/力模拟试验机,采用热膨胀法测定了不同铌含量低碳含铌微合金钢在不同冷速下的相变点,研究了奥氏体连续冷却时的相变行为及铌含量和冷却速率对该钢相变组织与硬度的影响。结果表明:随着铌含量和冷速的提高,γ→α相变温度降低,相变组织变得复杂,显微硬度升高;铌含量较低(小于0.024%,质量分数)的钢在冷速较低(3℃·S^-1)时,显微组织为较粗大的铁素体和少量珠光体,冷速提高后主要是由尖角形、多边形铁素体和贝氏体组成的混合组织;铌含量较高(0.06%)的钢在高冷速(50℃·S^-1%The transformation temperatures at different cooling rates of low-carbon Nb-bearing microalloyed steels with different Nb contents were obtained by thermal dilation method using Gleeble-1500D thermo-mechanical simulator. The transformation behavior of austenite during continuous cooling and the effects of Nb content and cooling rate on transformation microstructure and hardness were studied. The results show that the γ→α transformation temperature lowered, the microstructure became more complex and the microhardness increased with the increase of Nb content and cooling rate. The microstructure of the steel with low Nb content (〈0. 024wt%) was composed of coarser ferrite and minor pearlite at slow cooling rate of 3℃ · s^-1 , the sharp-angle shaped and polygon shaped ferrite as well as banite were got at higher cooling rates. The acicular ferrite was got at higher cooling rate (50 ℃ · s^-1) in the higher Nh content (0.06wt%)steel.

  3. Effect of Ce on the Purifying Degree and Inclusion modification of Low Carbon and High-Strength Steel%Ce对低碳高强度钢液夹杂物变性的研究

    Institute of Scientific and Technical Information of China (English)

    贺磊; 侯阳; 原春阳; 郭清理; 王社斌

    2013-01-01

    用真空感应炉在800 Pa的Ar气氛中把3.0 kg工业纯铁与合金元素熔化,在1873K加入Ce元素精炼10min,制备4种0.08C-0.6Si-0.45Mn-0.3Cu-0.09P-xCe的钢样.用化学成分、SEM和EDS表征结果,研究该体系中洁净度和夹杂物的变化.结果表明[Ce]为0时,夹杂物为MnS-MgO-Al2O,系;[Ce]为0.008% ~0.020%时,夹杂物为MgO-Al2O3-Ce2O2S系;[Ce]为0.043%时,夹杂物为FePCe-Ce2O3系,且把7μn以上形状不规则的夹杂物变为2μn球状,甚至转变为0.3μm以下的球形夹杂物,钢材基体上夹杂物残留面积减少58.1%,且尺度均小于3μm.钢液深度净化的原因是,Ce脱O、S后生成的夹杂物上浮、排除,不同类型夹杂物的成因与其形成的热力学条件相关.%In order to improve the refining process of low carbon and high-strength container plates,four steel samples were prepared by adding Ce into the molten steel containing 0.08C-0.60Si-0.45Mn-0.3Cu0.09P(mass%) at 1 873 K in a 3.0 kg vacuum induction furnace under Ar atmosphere (800 Pa).The chemical composition,SEM and EDS analytic results were obtained to study the cleanliness of 0.08C-0.60 Si-0.45Mn-0.3Cu-0.09P-xCe(mass%) steel and the change of inclusions.When [Ce] content was 0,the inclusions were MnS-MgO-A12O3 system; when [Ce] content was in the range of 0.008% ~0.020%,the inclusions were MgO-Al2O3-Ce2O3 system; when [.Ce] content was 0.043%,the inclusions became FePCe-Ce2O3 system and spherical inclusions of 2 μn or even smaller than 0.3 μm were transformed from 7 μm inclusions with irregular shape.The residual area of inclusions in the steel matrix was reduced by 58.1% and the size of inclusions was below 3 μm approximately.The liquid steel was cleaned profoundly due to the floating up and removal of inclusions which were formed by Ce deoxidation and desulfuration.The formation of different kinds of inclusions was relevant to the relative thermodynamic conditions.

  4. CSP 流程低碳铝镇静钢铸坯碳覆夹杂物析出行为%Precipitation behavior of carbon bearing inclusion in a slab for low carbon Al-killed steel

    Institute of Scientific and Technical Information of China (English)

    郭靖; 程树森; 李积鹏; 颜坤; 梅亚光

    2016-01-01

    在使用 CSP 工艺生产低碳或超低碳钢时,在铸坯中,特别是铸坯宽面的中心经常观察到相当数量的微米级碳覆夹杂物.通过对 CSP 流程不同的钢种铸坯取样,研究了这类夹杂物的结构特点和析出机制.指出碳覆夹杂物呈双层结构,外面包裹一层富碳层、中心为钙铝酸盐或含 CaO 的复合夹杂物.热力学计算结果显示这层富碳物质并非 CaC2.通过对比球墨铸铁中球状石墨的形成条件,指出 CSP 铸坯中存在冷却速度快、S 元素含量低、加钙处理后促球化元素 Ca、Mg 含量相对较高,有大量夹杂物作为形核核心等促进碳覆夹杂物析出的有利条件.C 为易偏析元素,在低碳或超低碳钢铸坯凝固过程中液芯中 C 含量的升高,能够析出球状的碳覆夹杂物.并指出由于碳覆夹杂物的析出,中心钢基体 C 含量降低,碳覆夹杂物析出能够减轻铸坯凝固过程中 C元素的偏析程度.%A kind of carbon bearing inclusion was frequently detected in the slab,in particular in the central part of a slab,of low carbon or ultra-low carbon steel produced by compact strip production (CSP)process.The struc-ture and the formation mechanism of carbon bearing inclusion was studied in different kinds of steel grades pro-duced by CSP process.It finds that the carbon bearing inclusion presents a duplex structure,in which the outer layer composes of graphite rich material and the inner core composes of calcium aluminates or CaO rich multi-com-ponent oxide.Thermodynamic analysis shows that the precipitation of carbon bearing inclusions are not CaC2. In addition,by comparing with spherical graphite formation conditions in spheroidal graphite cast iron,it finds that during the CSP slab solidification,the cooling rate is relative high,the sulfur content is very low,the Ca and Mg content which are beneficial to spherical inclusion formation are relative rich after Ca-treatment and there are a lar

  5. Quality Evaluation of Zinc-nickel Alloy Layer on Low Carbon Steel Surface%低碳钢表面锌-镍合金镀层的质量评价

    Institute of Scientific and Technical Information of China (English)

    郑凯; 施凯顺; 李红艺; 韩玉华; 崔俊; 施文静

    2013-01-01

    In alkaline medium, zinc-nickel alloy was electroplated on the low carbon steel surface in a plating bath containing polarized solvent. The qualities of coatings were tested according to national standards. The analyzing results indicate that adhesion and glossiness of the coatings are fine. The surface morphology and composition of coatings were analyzed by SEM. The results show that coating thickness is even and the compactness is good. Meanwhile, the alloy layer is mainly made up of nickel atoms and zinc atoms, the atom ration of nickel is 16 percents and that of zinc is 84 percents. The form of crystalline of alloy was determined by the X-ray diffraction spectrogram. The analyzed results show that crystal of the alloys was y crystal.%在碱性介质中,采用含有极化剂的溶液在低碳钢表面电镀锌-镍合金,按照国家相关标准对镀层进行质量检测,通过电子扫描电镜对镀层表面形貌和成分进行分析.结果表明,电镀层附着力好,粗糙度低,镀层厚度均匀、致密度好,锌-镍合金镀层中w(镍)和w(锌)分别为16%和84%;采用X-射线衍射仪分析锌-镍合金的结构,晶型为γ晶型.

  6. Microbiological Corrosion in Low Carbon Steels

    Directory of Open Access Journals (Sweden)

    O. Medina–Custodio

    2009-01-01

    Full Text Available The Microbiologically Induced Corrosion affects several industries, such as oil industry where it is estimated that 20% to 30% pipes failures are related with microorganism . The chemical reactions generate ions transfer, this validate the use of electrochemical techniques for its analysis. Coupons submerged in a nutritional medium with presence and absence of three different microorganisms during two periods, 48 hours and 28 days we restudied. Polarization resistance (Rp and Electrochemical Impedance Spectroscopy (EIS techniques we re applied to determine the corrosivity of the systems. The results show a greater corrosive effect of abiotic system, this indicates a microorganisms protection effect to the metal, opposite to the first hypothesis. This result was ratified observing surfaces coupons by using Scanning Electron Microscopy (SEM technique. A possible mechanism based on Evans – Tafel graph is proposed to explain inhibitor microorganism effect.

  7. 超低碳铝镇静钢冶炼过程氮含量的控制%Nitrogen control of ultra-low-carbon Al-killed steel in a smelting process

    Institute of Scientific and Technical Information of China (English)

    王敏; 张超杰; 蔡小峰; 张思源; 郭昭桥

    2016-01-01

    Based on the fact of high nitrogen pick-up, large nitrogen fluctuation and poor control in some steel works, the main aspects of nitrogen removal and nitrogen pick-up in an ultra-low-carbon Al-killed steel smelting process were summarized by analyzing the process data and sampling. The main sections for nitrogen removal are BOF decarburization period and vacuum treatment. High decarburization amount can lower the nitrogen content at the BOF endpoint. There is just a limited effect of switching between nitrogen and argon on the final nitrogen content at the BOF endpoint before the point of 70% oxygen blowing. Free oxygen is favorable for deni-trification by promoting the reaction of carbon and oxygen under the RH mode, in contrast under the VD mode. When free oxygen in liquid steel is controlled above 200 í10 -6 , the nitrogen absorption during tapping can be controlled within 5 í10 -6 . The nitrogen introduction of furnace charge is the important factor of nitrogen pick-up during the vacuum refining process, and it is up to 11í10 -6 . The minimum of nitrogen pick-up can reduce to 1í10 -6 by adopting gasket sealing and argon blowing protection simultaneously.%针对企业冶炼超低碳铝镇静钢过程中增氮量高、波动大及控制不稳定的问题,采用工艺数据统计和现场取样的手段,系统梳理了冶炼过程钢液脱氮和增氮的主要环节和影响因素.转炉脱碳期和真空处理是脱氮的主要环节,碳氧期的总脱碳量高则终点氮含量低;转炉底吹N2/Ar切换点在吹炼70%以前对终点氮含量影响不大;VD在无氧条件下脱氮有利,RH则在有氧条件下脱氮有利.控制钢中溶解氧>200×10-6则出钢过程增氮可控制在5×10-6以下;炉料的氮带入是真空精炼环节增氮的重要因素,最高达11×10-6;采用密封垫+吹Ar的保护方式,增氮量最低为1×10-6.

  8. 含Ti微合金低碳钢连续冷却过程中组织演变行为%Transformation behavior of Ti microalloyed low carbon steel during continuous cooling

    Institute of Scientific and Technical Information of China (English)

    利成宁; 袁国; 康健; 王国栋

    2016-01-01

    The transformation behavior of Ti microalloyed low carbon steel during continuous cooling was investigated by thermal dilation method and metallographic analysis,and the effects of Ti content and cooling rate on the transformation were discussed.The results show that Ti microalloying element plays important roles in refining the ferrite grains,suppressing the ferrite transformation and promoting the transformations of bainite and martensite.When the Ti content increases from 0.015% to 0.10%,the average grain size of ferrite obtained at 0.5 ℃ /s decreases from 24.5 μm to 13 μm,the range of cooling rate for ferrite transformation narrows from lower than 5 ℃ /s to lower than 1 ℃ /s,and the critical cooling rate of martensite transformation reduces from 40 ℃ /s to 20 ℃ /s.The transformation behaviors,especially the starting temperature of diffusion transformation,are governed by the combined effects of Ti content and cooling rate.%通过热膨胀法及金相分析法,研究Ti含量为0.015% ~0.10%的低碳钢连续冷却条件下组织演变行为,探讨了Ti含量及冷却速率对低碳钢相变行为的影响规律.结果表明,Ti微合金元素具有细化铁素体晶粒尺寸,抑制铁素体相变,促进贝氏体和马氏体相变的作用.当Ti含量由0.015%增加至0.10%时,0.5℃/s下获得的铁素体平均晶粒尺寸可由24.5 μm细化至13 μm,铁素体相变的冷却速率范围由≤5℃/s缩小至<1℃/s,马氏体临界冷却速率由40℃/s降低至20℃/s.冷却速率及Ti含量共同决定Ti微合金低碳钢的组织演变行为,特别是对扩散型的相变开始温度具有显著的影响.

  9. Maldives Low Carbon Development Strategy

    DEFF Research Database (Denmark)

    Fenhann, Jørgen Villy; Ramlau, Marianne

    This report presents the findings of a study for low carbon development strategy for Maldives. The study was implemented under the Memorandum of Understanding between the Ministry of Environment and Energy (MEE), Maldives and URC and was financed by Danida, Denmark’s development aid agency under...

  10. Effect of Humidity on Corrosion Behavior of Low Carbon Steel in Atmosphere Containing SO_2%含SO_2大气中湿度对低碳钢腐蚀行为的影响

    Institute of Scientific and Technical Information of China (English)

    林翠; 陈三娟; 肖志阳

    2012-01-01

    Through simulated polluted atmospheric corrosion system,the effect of relative humidity(RH) on the corrosion morphology and the growth process of corrosion products of 20 low carbon steel in atmosphere containing 5×10-6 volume fraction SO2 was studied by means of optical microscopy,SEM,XRD and XPS.The results show that the corrosion products were mainly composed of α-FeOOH,γ-FeOOH,FeSO4,Fe3O4,γ-Fe2O3 under the enviroment of different relative humidities,and the concentration of FeOOH increased with increase of RH,and the corrosion rate increased,too.When the RH were 65% and 75%,the corrosion curves was divided into two stages which respectively followed by exponential increase and the linear growth.When the RH were 85% and 95%,the corrosion curves followed by linear growth.At the enviroment of RH of 65%,the corrosion products grew in the form of corrosion-ring.With increase of RH,the filiform corrosion products were found around the corrosion-ring.When the RH was 95%,it was filiform corrosion products with cellular corrosion products,and obvious pits were observed under the cellular corrosion products.%采用模拟污染大气腐蚀系统,利用光学显微镜、SEM、XRD和XPS等研究了湿度对含体积分数为5×10-6的SO2环境中20低碳钢腐蚀形貌和腐蚀产物生长过程的影响。结果表明:在不同湿度环境中,腐蚀产物均主要由α-FeOOH、γ-FeOOH、FeSO4、Fe3O4、γ-Fe2O3组成;随湿度增大,FeOOH含量增多,低碳钢的腐蚀速率增大;在相对湿度为65%,75%时,腐蚀曲线分为指数增加和线性增加2个阶段,在85%,95%时,腐蚀曲线符合线性增长规律;在相对湿度为65%的环境中,腐蚀产物主要以腐蚀圈形式生长,随着相对湿度增加,腐蚀圈周围有短小丝状腐蚀产物出现;在相对湿度为95%时主要为丝状腐蚀产物,其上伴随有胞状腐蚀产物生成,且在胞状腐蚀产物下存在明显的腐蚀坑。

  11. Some Considerations about Low-Carbon Logistics

    Institute of Scientific and Technical Information of China (English)

    LI Yifan

    2013-01-01

    More and more People have paid attention to low-carbon logistics.This article,based on the characteristics of low-carbon logistics,proposes the effective ways to achieve low-carbon logistics,including logistics information,effective supply chain management,establishing environmental logistics and reverse logistics.

  12. Recent Development of Air-Cooled Bainitic Steels Containing Manganese

    Institute of Scientific and Technical Information of China (English)

    FANG Hong-sheng; YANG Fu-bao; BAI Bing-zhe; YANG Zhi-gang; YIN Jiang

    2005-01-01

    The superiorities of air-cooled bainitic steels were described.A series of air-cooled bainitic steels containing manganese were developed and presented,which include low carbon granular bainitic steels,low carbon grain-boundary allotriomorphic ferrite/granular bainite dual phase steels,medium and medium high carbon bainite/martensite dual phase steels and casting bainitic steels.The development of ultra-low carbon bainitic steels in China was also introduced.

  13. Low Carbon: Do the Green Thing

    Institute of Scientific and Technical Information of China (English)

    Wang Ting

    2010-01-01

    @@ Apparently,till the end of the year 2009,the words related with climate change,Copenhagen,as well as low-carbon almost spread all over the world.Just click the web,only 0.14 seconds,nearly 27,600,000 low-carbon related results were showcasing obviously.Low carbon economy,low carbon life...the things that related with the 'low-carbon' has become a trend or a focus,gradually changing our daily life;or,the whole world cares more about their living condition and makes effort to avoid suffering the crack of doom that the '2012' told us.

  14. 基于熵值法的钢铁企业低碳竞争力评价%Low Carbon Competitiveness Evaluation of Steel Enterprise Based on the Entropy Value Method

    Institute of Scientific and Technical Information of China (English)

    范莉莉; 江玉国

    2016-01-01

    通过对钢铁企业现状的描述和经典文献的研究,构建了钢铁企业的低碳竞争力评价指标体系;提出了熵值法的评价模型,在搜集全国重点钢铁企业相关数据的基础上,运用该模型计算了各指标的信息熵、效用值、权重;通过实证研究得出了样本企业的低碳竞争力水平。%Firstly,this paper builts the low-carbon competitiveness evaluation index system,through the description of the present situation of iron enterprises and classical literature research,and chose the evaluation indexs. Then,it puts forward the evaluation method of entropy model. It screenes and scores,empoweres the indicators. Finally,it empirically studies samples of low-carbon enterprise competitive level.

  15. Microstructure and mechanical properties of transient liquid phase diffusion bonding region of low carbon steel-brass-stainless steel composite tube%碳钢-黄铜-不锈钢瞬间液相扩散结合区组织与性能

    Institute of Scientific and Technical Information of China (English)

    张锋刚; 景然; 王永善; 宋佩维

    2016-01-01

    采用OM、SEM、EDS、EPMA、显微硬度和剪切试验等方法,研究了H62黄铜中间层20钢/304不锈钢瞬间液相扩散结合区组织与性能.结果表明,结合区发生Fe、Cr、Ni、Cu、Zn原子互扩散,异种金属界面获得良好的冶金结合,抗剪强度可达到270 MPa以上;碳钢/黄铜界面有含Cr、Cu、Ni、Zn的“岛状”富铁相形成,扩散温度由950℃增加至1100℃,岛状组织形态由不连续状转变为连续状,并向黄铜中间层中生长,随着扩散时间的延长,贯穿于中间层,使结合区硬度增加,抗剪强度提高;950℃扩散复合,碳钢/黄铜界面有铬碳化物形成,剪切断裂发生该处,断口呈脆性穿晶断裂;1100℃扩散复合,碳钢/黄铜界面无铬碳化物形成,剪切断裂发生在黄铜/不锈钢界面,断口呈韧性断裂.%Microstructure and mechanical properties of the transient liquid phase diffusion bonding region of low carbon steel/stainless steel composites with H62 brass interlayer were examined by means of OM,SEM,EDS,EPMA,microhardness and shear tests.The results show that the metallurgical bond of the different metal interface is achieved by the inter-diffusion of Fe,Cr,Ni,Cu and Zn in the diffusion bonding zone,and the compression shearing strength above 270 MPa is obtained.The island iron-rich phase,which contains Fe,Cr,Ni,Cu and Zn,forms at the copper/stainless steel interface.With increasing diffusion temperature from 950 ℃ to 1100 ℃,the island ironrich phase changes from discontinuous to continuous and grows into the brass inter layer,and the micorhardness and shearing strength of the bonding zone increases.Shear failure occurs at the carbon steel/brass interface and fracture surface shows brittle transgranular fracture for the diffusion bonding at 950 ℃,which is attributed to the formation of chromium carbide while shear failure occurs at the brass/stainless steel interface and fracture surface shows ductile fracture for the diffusion bonding at 1100

  16. Low Carbon:Do the Green Thing

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Apparently, till the end of the year 2009, the words related with climate change, Copenhagen, as well as low-carbon almost spread all over the world. Just click the web, only 0.14 seconds, nearly 27,600,000 low-carbon related results were showcasing obviously. Low carbon economy, low carbon life…the things that related with the ’low-carbon’ has become a trend or a focus, gradually changing our daily life; or, the whole world cares more about their living condition and makes effort to avoid suffering the crack of doom that the ’2012’ told us.

  17. Overview of Low-carbon Economy Research

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The paper has a detailed literature review in low-carbon economy research of academic circle in our country from three aspects that are conception and connotation of low-carbon economy, necessity and urgency of developing low-carbon economy and path choice of realizing low-carbon economy in our country. low-carbon economy is the "green economy" that obtains the maximum output by discharging minimum greenhouse gases with the main characteristics of "three low and three high" that are low energy consumption, low pollution, low discharge and high effect, high efficiency, high benefit. To China, developing low-carbon economy is the inevitable choice in realizing peaceful rising and sustainable development as a responsible large country. It conforms to world trends and corresponds to China’s actual conditions. Finally, the paper makes a overview of the path choice in realizing low-carbon economy in our country from eight aspects-integral countermeasures and suggestions, technology innovation, consumption pattern innovation, policy innovation, environmental and financial innovation, building low-carbon city, establishing carbon trading market and developing low-carbon agriculture.

  18. 纳米SiC粉体对铸造超低碳马氏体不锈钢耐磨蚀性能的影响%Effect of Nano-SiC Powders on Abrasion Properties of Ultra-Low Carbon Martensitic Stainless Cast Steel

    Institute of Scientific and Technical Information of China (English)

    杨军; 王鑫; 陈美玲; 高宏; 杨莉

    2011-01-01

    水轮机用铸造超低碳马氏体不锈钢遭受着泥砂冲刷和腐蚀的双重作用.在生产条件下将经过表面改性处理的纳米SiC粉体加入到铸造超低碳马氏体不锈钢中,分别在加与不加NaCl的两种水砂粒介质中进行磨蚀试验,研究纳米SiC粉体加入量对其耐磨蚀性能的影响.结果表明:纳米SiC粉体强化处理后马氏体不锈钢表现出优越的耐磨蚀性能,其材料失重形式主要为韧性断裂,当SiC加入量为0.1%时,在水砂粒和3.5%NaCl水砂粒中磨蚀率分别降低了90%和86%.%The turbine steel has to suffer the dual effects of sediment erosion and corrosion. The nano-SiC powders were poured into the melt for ultra-low carbon martensitic stainless steel, and the abrasion test was carried out in sand-water mixture with and without NaCI to study the effect of nano-SiC powder addition on corrosion resistant properties of the steel. The results show that the martensitic stainless steel strengthened by nano-SiC powders shows superior abrasion performance. When the addition of SiC powders is 0.1%, the erosion rates in the sand-water mixture with 3.5% NaCI and sand-water mixture without NaCI, decrease by 86% and 90%, respectively.

  19. Physical and chemical evaluation of the effect of a magnetic field on the electrodeposition of Ni in low carbon steel; Evaluacion fisica y quimica del efecto de un campo magnetico en la electrodeposicion de Ni en acero bajo carbono

    Energy Technology Data Exchange (ETDEWEB)

    Campo G, G. A.

    2015-07-01

    In this study nickel coatings were obtained, with and without the presence of magnetic field at 60 degrees Celsius for 7, 12 and 17 minutes on substrates of AISI 1018 carbon steel, from a classical type Watts solution. The properties of the coatings were studied by X-ray diffraction, scanning electron microscopy and atomic force microscopy, hardness tester and roughness tester, the electrochemical behavior of the films was also studied through RP and EIE and also capacitance calculations, corrosion rate and thickness were made. In general, the magnetic field has a negative influence on the physical and chemical properties of an electrodeposited Ni steel AISI 1018. The details are discussed in this research. (Author)

  20. Low-Carbon Innovation and Development

    DEFF Research Database (Denmark)

    Lema, Rasmus; Johnson, Bjørn; Andersen, Allan Dahl

    In this Thematic Review we communicate relevant insights from the Globelics research community to policy circles and development donor organisations. The key issues addressed are, firstly, how the notion of LICS can help us understand the challenges of low carbon development (LCD), and secondly, ......, a discussion of the design of support structures for the building of LICS that contribute to low-carbon development....

  1. Green Growth and Low Carbon Society

    DEFF Research Database (Denmark)

    Müller, Anders Riel; Tonami, Aki

    This paper ask the question of what makes Low Carbon and Green Growth and Low Carbon Society policy concepts that have not only gained foothold in their countries of origin, but also globally. Autobiography analysis is employed to discover the stories that these concepts tell about developmental ...

  2. Ce2O3微粒对低碳钢夹杂和晶粒度的影响%Effect of Ce2O3 Particle on Crystal Grain Size and Inclusion of Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    彭军; 王键; 李样兵; 郭瑞华; 安胜利

    2012-01-01

    The effect of Ce2O3 particle on inclusion and crystal grain size of steel product was studied by adding Ce2O3 particle into steel. The result shows the content of inclusion in steel will not increase when the particle size of Ce2O3 is lower than 1.13 |xm, but the content of inclusion will obviously increase when the size is higher than 2.34 μm. The Ce2O3 particle can combine with sulfide inclusion and deoxided product, which has the same function as adding rare earth alloy into steel partially. The Ce2O3 particle can reduce the size of crystal grain of cast structure. The average size of crystal grain is reduced from 180 μm to 90~75 μm. And it can also reduce the size of crystal grain of rolled structure. The degree is reduced from level 6.5 to level 11. The best economic and technical norms can be got when the size of Ce2O3 particle is 1.13 μm and the adding content is 0.5% of the content of metal.%通过在钢中外加Ce2O3微粒的方法,研究Ce2O3微粒对钢材夹杂物和晶粒度的影响.结果表明,Ce2O3粒度不大于1.13 μm时,钢中夹杂物含量不会增加,粒度大于2.34 μm时夹杂物含量会明显增加.外加Ce2O3微粒可以和钢中硫化物夹杂和脱氧产物结合,起到加稀土合金的部分作用.Ce2O3微粒可以细化铸态晶粒的粒度,晶粒平均尺寸由180 μm降低到90~75 μm;也可显著降低轧态组织的晶粒度,使晶粒度由6.5级降低到11级.当添加Ce2O3微粒粒度为1.13 μm,加入量为金属量的0.5%时,可以取得最好的经济技术指标.

  3. 重碳酸盐溶液中SO2-4和Cl-对低碳钢活化/钝化腐蚀行为的影响%EFFECTS OF SO2-4 AND Cl-ON ACTIVE/PASSIVE CORROSION BEHAVIORS OF LOW CARBON STEEL IN DEAERATED BICARBONATE SOLUTION

    Institute of Scientific and Technical Information of China (English)

    阳靖峰; 董俊华; 柯伟

    2011-01-01

    The corrosion behaviors of low carbon steel, a kind of materials used in making metal container sealing high-level radioactive waste, in three deaerated bicarbonate solutions simulated the ground water, 0.1 mol/L NaHCO3 solution, 0.1 mol/L NaHCO3+0.1 mol/L Na2SO4 solution and 0.1 mol/L NaHCO3+0.1 mol/L NaCl solution, were examined. The results in potential evolution revealed that the low carbon steel moved up to the passive state in 0.1 mol/L NaHCO3 solution while moved up to the re-active state in the other solutions. SEM observations showed that the low carbon steel was not corroded in 0.1 mol/L NaHCO3 solution, while homogeneous corrosion occurred in 0.1 mol/L NaHCO3+0.1 mol/L Na2SO4 solution and local corrosion in the third solution. XRD analyses illustrated that the corrosion products are composed of Fe3O4 and α-FeOOH.%在除O2的0.1 mol/L NaHCO3,0.1 mol/L NaHCO3+0.1 mol/L Na2SO4以及0.1 mol/L NaHCOa+ 0.1 mol/L NaCl溶液中,用恒电位法在低碳钢电极表面制备腐蚀产物,并原位监测低碳钢的开路电位,用SEM观察腐蚀形貌,用XRD确定腐蚀产物的相组成.结果表明,在0.1 mol/L NaHCO3溶液中,低碳钢的开路电位最终处于再钝化区间,其表面未观察到明显的腐蚀现象;在0.1 mol/L NaHCO3+0.1 mol/L Na2SO4溶液中,低碳钢的开路电位最终处于再活化区间,其表面发生均匀腐蚀;在0.1 mol/L NaHCO3+0.1 mol/L NaCl溶液中,低碳钢的开路电位最终亦处于再活化区间,而其表面却发生局部腐蚀.XRD结果表明,低碳钢表面的腐蚀产物主要为Fe3O4和α-FeOOH.

  4. Applicability Assessment of Phase Transfromation Models of Low Carbon Steel in Laminar Flow Cooling Process%层流冷却过程低碳钢相变模型的适用性分析

    Institute of Scientific and Technical Information of China (English)

    程杰锋; 唐广波; 刘正东

    2011-01-01

    Available austenite phase transformation models of C-Mn steels were collected and compared to investigate their applicability. Five groups of incubation period models (according to Scheil's additivity rule) were used to calculate ferrite transformation start temperature, seven groups of avrami equations were used to describe phase transformation kinetic process, and five groups of grain size models were used to predict ferrite grain size after transformation completion. By use of a developed integrated process modeling system in which thermal, mechanical and metallurgical processes from reheating furnace to coiling of a steel strip had been numerically and successfully coupled together. Phase transformation process was investigated under three different runout table cooling conditions (cooling rate is 10 ℃/s, 20 ℃/s and 40 ℃/s respectively) during hot strip rolling at 2050 HSM of Baosteel Co. Ltd. Applicability of phase transformation models were discussed by comparing the calculated data with experimental data. The results show that models proposed by Kwon are suitable for the incubation period,models of Avrami equations proposed by Liu, Donnay and Sun are suitable for the kinetics of phase transformation, and for the ferrite grain size, models proposed by Hodgson is suitable.%选取了现有典型的C-Mn钢相变过程的物理冶金模型,包括5组孕育期模型、7组相变动力学方程模型、5组相变后铁素体晶粒尺寸模型.利用自行开发的组织性能预报系统软件模拟计算了在3组实际冷却工艺条件下各模型的奥氏体转变过程,并对各模型进行了评价.结果表明,对于所设定的成分和工艺条件,适用性较好的孕育期模型是Kwon所提出的模型;适用性较好的动力学方程模型是Liu、Donnay和Sun所提出的模型;适用性较好的铁索体晶粒尺寸模型是Hodgson所提出的模型.

  5. Study on in-situ observation of martensitic transformation in low carbon steel by high temperature confocal laser scanning microscopy%低碳钢在高温共焦激光扫描显微镜下马氏体相变的原位观察研究

    Institute of Scientific and Technical Information of China (English)

    班丽丽; 温娟; 史学星; 刘卫平

    2011-01-01

    利用高温共焦激光扫描显微镜,对低碳钢进行了马氏体相变的原位动态观察.结果表明,实验用低碳钢在连续冷却过程中形成板条马氏体,Ms点约为373℃,Mf点约为300℃.板条马氏体主要在退火孪晶处以及奥氏体晶界及其角隅处形核,或者在先形成的板条处形核,再以60°或120°角向奥氏体晶内生长.板条束的形成也有两种类型,一类以先形成的板条为基准逐步形成彼此平行的板条束,另一类则由先形成的板条触发60°或120°方向的板条.最终构成正三角形、平行四边形等几何形状.%The in-situ dynamical observation of martensitic transformation in low carbon steel was carried out by high temperature confocal laser scanning microscopy (CLSM). It was found that lath martensite was formed in experimental low carbon steel in continuous cooling process as the temperature reached about 373 °C (Ms). And the transformation stopped at about 300 °C (Mf). The lath martensite was mainly nucleated in annealing twin boundaries and austenitic boundaries &. Corners, or nucleated in previously formed laths and then developed to austenitic crystal at 60° or 120°. Furthermore, there were two types for the formation of lath bundle: one was parallel lath bundle which was gradually formed based on the previously formed laths; the other was laths which finally formed geometrical shapes such as regular triangle and parallelogram after being triggered by the previously-formed laths.

  6. Strategies for Local Low-Carbon Development

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Nan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fridley, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ohshita, Stephanie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Khanna, Nina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Min, Hu [Energy Foundation China, Beijing (China); Xiulian, Hu [Energy Research Inst., Beijing (China)

    2012-11-14

    Cities around the world are implementing policies and programs with the goal to reduce greenhouse gas emissions, as well as save energy, reduce costs, and protect the local, regional, and global environment. In China, low-carbon development is a key element of the 12th Five Year Plan. Pilot low-carbon development zones have been initiated in five provinces and eight cities and many other locations around China also want to pursue a low-carbon development pathway. This booklet provides information for government officials, policy makers, program designers and implementers, provincial and city planners, and others who want an overview of the key options available for low-carbon development at local level. These Strategies for Local Low-Carbon Development draw from successful experiences from around the world. Information is provided for low-carbon actions that can be taken in the sectors of (1) Industry, (2) Buildings and Appliances, (3) Electric Power, (4) Consumption and Waste Management, (5) Transportation and Urban Form, and (6) Agriculture and Forestry. A description of each policy is provided along with information on the stakeholders involved in implementation, the conditions for successful implementation, the expected energy and carbon savings, and the policy cost-effectiveness. Case studies show how each policy has been implemented somewhere around the world. While there are many low-carbon options available for local implementation, this booklet aims to provide guidance on those that have been most successful, that have the largest impact, and that are cost-effective in order to support low-carbon development efforts in Chinese cities.

  7. Atmospheric corrosion of low carbon steel in a polar marine environment. Study of the effect of wind regime; Corrosion atmosferica del acero bajo en carbono en un ambiente marino polar. Estudio del efecto del regimen de vientos

    Energy Technology Data Exchange (ETDEWEB)

    Rivero, S.; Chico, B.; Fuente, D. de la; Morcillo, M.

    2007-07-01

    The present work studies the atmospheric corrosion of carbon steel (UNE-EN 10130) in a sub-polar marine environment (Artigas Antarctic Scientific Base (BCAA), Uruguay) as a function of site atmospheric salinity and exposure time. A linear relationship is established between corrosion rate and airborne salinity deposition rate, valid in the deposition range encountered (125-225 mg Cl-l/m{sup 2}.d) and a bi logarithmic relationship established between corrosion and exposure time (1-4 years). Atmospheric salinity is related with the monthly wind speed average, based on the concept of the wind run. chloride ion deposition rates of less than 300 mg Cl-l/m{sup 2}.d are related with remote (oceanic) winds and coastal winds basically of speeds between 1-40 km/h, while higher deposition rates (300-700 mg Cl-/m{sup 2}.d) correspond to coastal marine winds of a certain persistence with speeds of between 41-80 km/h. (Author) 39 refs.

  8. Effect of solid solute carbon on hardening property of ultra-low carbon bake hardened steel%固溶碳含量对 ULC-BH 钢烘烤硬化性能的影响

    Institute of Scientific and Technical Information of China (English)

    杨晰; 李维娟; 金晓龙; 刘洋; 孙成钱

    2014-01-01

    研究了固溶碳含量对ULC-BH钢烘烤硬化性能的影响,测量了不同烘烤时间下的烘烤硬化( BH )值,通过内耗试验分析固溶碳含量变化。结果表明,对试样进行相同预变形、不同时间烘烤硬化处理后,随烘烤时间增加,BH值先快速增大再基本不变最后增大;Snoek峰峰高随烘烤时间的延长而降低,固溶碳含量随时间延长而降低;对于试验钢,常规的烘烤工艺170℃×20 min没有达到最大的BH值,但继续增加烘烤时间BH值提高缓慢。%Effect of solid solute carbon on hardening property of ULC-BH steel was studied in this paper .The BH value of the samples with different aging time were measured and the variation of solid solute carbon amount was analyzed by internal friction test .The result shows that the BH value increases rapidly at first , then basically remains the same and increases slowly at last with the increasing aging time dealing with same pre-strain;The height of Snoek peak and solute carbon amount decreases with the increasing aging time ;The BH value does not increase to maximum with the normal baking process 170 ℃×20 min, but increases slowly if samples are increased aging time .

  9. Simulación del vaciado continuo de perfiles de aceros al carbono de baja aleación//Simulation of the continuous casting of low carbon steel profiles

    Directory of Open Access Journals (Sweden)

    Yusdel Díaz-Hernández

    2012-12-01

    Full Text Available En este artículo se presentó un algoritmo para simular el proceso de vaciado continuo a partir de la construcción de un modelo físico matemático utilizando el Método de los Elementos Finitos. Como característica más destacada del algoritmo se encuentra la consideración de los procesos complejos de intercambio de calor, cambio de fase del metal, distribución de temperaturas en el molde, composiciónquímica del metal, flujo de agua en el enfriamiento primario y secundario, y la velocidad de colada. El algoritmo permitió predecir con suficiente pericia el comportamiento de las variables durante el proceso de vaciado continuo de acero según perfil y marca del mismo.Palabras claves: simulación, solidificación, vaciado continuo, modelado._______________________________________________________________________________AbstractIn this paper an algorithm to simulate the process of continuous casting based on a physical – mathematical model using finite element methods was presented. The most outstanding characteristic of the model was the inclusion of complex processes of heat interchange, metal phase changes, distribution of temperatures in the mould, chemical composition of the metal, flow of water in the primary andsecondary cooling system and the casting speed. Moreover, the algorithm permitted to predict the behaviour of the process variables in the continuous casting of steel according to its profile and type.Key words: simulation, solidification, continuous casting, modelling.

  10. Research and Application of Lost Foam Technology of Low-Carbon Alloy Steel Casting%低碳合金钢铸件消失模铸造技术研究与应用

    Institute of Scientific and Technical Information of China (English)

    王新节

    2011-01-01

    运用计算机辅助三维设计、计算机辅助凝固过程数值模拟和计算机辅助数控编程制造CAD/CAE/CAM一体化技术手段,通过优化设计产品模型结构、铸造工艺参数、产品模具工装结构、浇冒口工艺系统以及模具型腔数控加工的刀具定位源文件,研究开发了货运列车低碳合金钢零部件转8A型承载鞍消失模铸件产品.与普通砂型铸造相比,其铸件单体重量减轻了3kg,铸件重量精度达到MT7级,铸件尺寸精度达到CT8级,铸造工艺出品率达到65%;本文也对大批量产生过程中容易出现的铸造缺陷进行了分析并提出了解决的办法.%By integrated technological medium of 3D CAD, computer aided solidification process numerical simulation engineering and computer aided NC programming manufacturing, by means of optimization of product pattern structure, foundry technological parameters, die auxiliary, equipment and tool, riser gating system and die cavity NC cutter location source file, the type of Z8A goods train lowcarbon alloy steel adapter lost foam casting has been developed. Comparedwith ordinary sand mold casting, the casting monomer weight lightened 3kg, grade of casting weight precision came to MT7, grade of casting size precision came to CT8, foundry yield came to 65% Casting defects easily appeared in the course of large quantities production have been analysed with solution methods offered

  11. Effects of cyclic cryogenic treatment on microstructure and mechanical properties of low carbon martensitic stainless bearing steel%循环冷处理对低碳马氏体不锈轴承钢组织和性能的影响

    Institute of Scientific and Technical Information of China (English)

    薛茹娜; 李绍宏; 袁晓虹; 姜雯; 孙虎代; 赵昆渝; 杨卯生

    2015-01-01

    Effects of cyclic cryogenic treatment on microstructure and mechanical properties of a Fe-Cr-Co-Ni-Mo low carbon martensitic stainless bearing steel were investigated. The results show that the martensitic laths refines. In corresponding, the hardness increases and the impact energy decreases with the cyclic cryogenic treatment and tempering time increasing. The retained austenite reduces during cryogenic treatment and at last about 2% thin film-like retained austenite is distributed between martensite laths after second tempering.%研究了循环冷处理对一种Fe-Cr-Co-Ni-Mo系低碳马氏体不锈轴承钢组织和性能的影响。结果表明,随着冷处理和高温回火次数的增加,马氏体板条细化,钢的硬度升高,相应的冲击吸收能量降低。冷处理促使钢中残留奥氏体量减少,最终约有2%的薄膜状残留奥氏体分布于马氏体板条间。

  12. Aplicación del rayo láser de CO2 para soldar laminas de acero bajo carbono // Application of the ray laser of CO2 to weld sheets of steel low carbon

    Directory of Open Access Journals (Sweden)

    Enrique J. Martínez D

    1999-07-01

    very thin sheets is facilitated, that which difficultly is achieved withthe processes common of welding. This technique also presents the advantage that easily you can automate, producing weldings ofhigh precision with low contamination.The study consists on carrying out an investigation on the process of welding of thin sheets using a laser of CO2 of low power incontinuous way, focusing the laser with a lens of ZnSe and using industrial argon to control the atmosphere around the treated regionand to avoid the oxidation. To carry out the process, you design a device for ' to displace the sample at 45o with regard to thetrajectory of the ray laser in precise form; the welding was carried out to it collides and without material contribution.The work was carried out on sheets of steel of low coal of caliber 24 and 26. The welded samples were subjected to: tractionrehearsal, visual analysis, analysis metalográfico and microdureza tests. The obtained results show that it can be carried out theprocess easily, by means of the control of the most important variables, in such a way that once established, the operator doesn't needa great experience in the handling of this technique to carry out the process with high quality. The carried out analyses confirm thatby means of this technique it is possible to obtain uniform welding cords, with good mechanical properties.Key words: Welding, laser.

  13. China Firmly Committed to Low Carbon Economy

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ The creation of a "low carbon" economy that will provide jobs and clean up industry is now a crucial policy objective for countries trying to spend their way out of the world economic downturn. A recent report by HSBC calculates that the United States is allocating 12 per cent of its fiscal stimulus to the green economy and China, 34per cent.

  14. Developing Potential of Low-carbon Agriculture in Heilongjiang Province

    Institute of Scientific and Technical Information of China (English)

    Yang Hui; Li Cui-xia; Chen Yao; Fu Rao

    2012-01-01

    Based on the trace of origin and development process of low-carbon economy, the paper defined the concept of low- carbon agriculture. As a case, the development of low-carbon advantage and disadvantage of agriculture in Heilongjiang Province made a systematic analysis of factors; it based on the empirical and comparative analysis of low-carbon development in Heilongjiang Province and put forward countermeasures and suggestions of agriculture. At last, the low-carbon agriculture was prospected in the future.

  15. INFLUENCE RESEARCH OF COLD PLASTIC DEFORMATION ON DIFFUSION SATURATION PROCESS BY CARBON AND BORON OF THE LOW-CARBON AND BORON-CONTAINING ALLOYS

    Directory of Open Access Journals (Sweden)

    N. Yu. Filonenko

    2010-06-01

    Full Text Available This work is devoted to the study of influence of cold prestrain with degree of deformation within the range 0…40 % on diffusion saturation with boron and carbon for low-carbon and boron steels. It is determined that the plastic prestrain with degree of deformation 20 % at temperature 750 °С for the low-carbon steel promote increasing of boron-cementation layer thickness by 25 % and microhardness of perlite layer by 20 %.

  16. Bacterial exopolysaccharides for corrosion resistance on low carbon steel

    Science.gov (United States)

    Corrosion is a global issue that affects safety and economics. There is an increasing demand for bio-based polymers for industrial applications and production of polymers by microorganisms is especially attractive. This work reports on the electrochemical and physical properties of exopolysaccharide...

  17. Low carbon steel: Metallurgical structure vs. mechanical properties

    Science.gov (United States)

    Shull, Robert D.

    1990-01-01

    The objective is to provide a low cost, simple experiment for either demonstration purposes or as a laboratory experiment that will teach the student the importance of the thermal-mechanical history of a metallic alloy in determining that material's mechanical behavior. Hairpins are subjected to various treatments. The experimental equipment and procedures are discussed.

  18. Investigation The Mechanical Properties of Carburized Low Carbon Steel

    Directory of Open Access Journals (Sweden)

    Dr. Mohammed Abdulraoof Abdulrazzaq

    2016-09-01

    Full Text Available microstructure, mechanical properties; hardness and wear resistance has been investigated taken different temperatures; (850, 900, and 950 ˚C with constant time (2 hr of carburizing process. The experimental work shows that at carburizing temperature (850 ˚C, the hardness was increases from the inside to outside of specimen from ( 102 to HV 250., while increases for temperatures (900 and 950 ˚C from (105 to 272 HV, and (115 to 192 HV respectively. This experiment also been conducted for wear resistance for harder specimen which was at 950 ˚C carburized sample for three times (2, 4 and, 6 hr and the wear rate was (9.99*10-6 g/m at (2 hr, and for (4 hr it was (12.7*10-6 g/m and at (6 hr it was (15.13*10-6 g/m.

  19. Characteristics of Strain-Induced Ferrite in Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    LI Wei-juan; LIU Cui-qin; WANG Guo-dong; LIU Xiang-hua

    2003-01-01

    The strain-induced ferrite formed under different conditions was observed with SEM and optical microscope. The nucleation sites of strain-induced ferrite include grain boundary, grain inside, deformed band and annealing twin boundary. The shapes of the ferrite accordingly are equiaxed irregular polygonal, strip-shaped and acicular.

  20. Uso del Parámetro de Redondez para Evaluar la Cavitación Intergranular en un Acero de bajo Carbono Microaleado con Niobio Deformado Isotérmicamente Use of the Roundness Parameter to Evaluate Intergranular Cavitation of Low Carbon Niobium Microalloyed Steel under Isothermal Deformation

    Directory of Open Access Journals (Sweden)

    E. Hurtado

    2005-01-01

    Full Text Available Se realizaron ensayos de tracción a temperaturas de 640°C, 840°C, 900°C y 960°C para velocidades de desplazamiento de cabezal de 1.35 mm/min y 13.5 mm/min para determinar el comportamiento de la formación de cavidades en un acero de bajo carbono microaleado con niobio deformado isotérmicamente. Después de la fractura en pruebas de tensión en caliente, un corte longitudinal de la muestra permite evaluar la forma y tamaño de las cavidades por microscopía óptica y análisis de imágenes. En ambos casos se presentaron cavidades en forma de zig-zag en las muestras ensayadas a 900°C, temperatura que está dentro de un intervalo donde hay la más baja ductilidad de este acero bajo cargas de tensión. Se encontró que las cavidades formadas 1.35 mm/min, para esta misma temperatura, presentan tamaños mayores y menor valor del parámetro de redondez.Hot tensile tests were carried out on low-carbon niobium microalloyed steel at four temperatures: 640°C, 840°C, 900°C and 960°C, for crosshead speeds of 1.35 mm/min and 13.5 mm/min in order to evaluate cavity formation behavior during isothermic deformation. After fracture in a hot tensile test, transverse sample sectioning allowed the evaluation of shape and size of cavities formed during the test using optical microscopy and image analysis. In both cases zigzag shaped cavities were observed at 900°C, a temperature within the range of the lowest ductility for this steel under uniaxial tensile load conditions. It was found that cavities formed at 1.35 mm/min at this temperature were greater in size, and had a lower relative value for the roundness parameter.

  1. Sharing a Low-Carbon Future

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ On March 25,2010,Office Park held the"Sharing a Low-Carbon Future with You"promotional conference for its new building,Tower C,situated in the center of the Beijing CBD.More than 150 representatives of agencies and media organizations in Beijing attended this grand event.The purpose of the event was to announce that Tower C is now officially ready for leasing.

  2. Contribution of archaeological analogs to the estimation of average corrosion rates and long term corrosion mechanisms of low carbon steel in soil; Apport des analogues archeologiques a l'estimation des vitesses moyennes et a l'etude des mecanismes de corrosion a tres long terme des aciers non allies dans les sols

    Energy Technology Data Exchange (ETDEWEB)

    Neff, D

    2003-11-15

    In the context of the French nuclear waste storage, a multi-barriers disposal is envisaged. Wastes could be put in metallic overpacks disposed in a clay soil. As these overpacks could be made of low carbon steel, it is important to understand the corrosion behaviour of this material in soil during period of several centuries. Indeed, it is necessary to consolidate the empirical data by a phenomenological approach. This includes laboratory experiments and modelling of the phenomenon which have to be validated and completed by the study of archaeological artefacts. This was the aim of this PhD-work. To this purpose, an analytical protocol has been elaborated: about forty archaeological artefacts coming from five dated sites (2. to 16. centuries) have been studied on cross section in order to observe on the same sample all the constituents of the system: metallic substrate/corrosion products/environment. The corrosion products are divided into two zones: the Dense Product Layer (DPL) in contact with the metal, and the Transformed Medium (TM) which are the corrosion products formed around soil minerals (quartz grains). The metallic substrate has been studied by the classical methods of materials science (optical and scanning electron microscope, energy and wavelength dispersive spectroscopies). It has been verified that despite their heterogeneity of structure and composition, they are all hypo-eutectoids steels that can contain phosphorous until 0.5 wt%. The corrosion products have been analysed by local structural analytical methods as micro-diffraction under synchrotron radiation ({mu}XRD) and Raman micro-spectroscopy. These two complementary techniques and also the elemental composition analysis conducted to the characterisation of the corrosion forms. On the majority of the samples coming from four sites, the DPL are constituted by goethite including marbles of magnetite/maghemite. On the artefacts from the fifth site, a particular corrosion form has been

  3. 基于Gurson-JC模型的铝合金6061T6和低碳钢Q235力学性能表征%Characterization of mechanical properties of aluminium alloy 6061T6 and low carbon steel Q235 based on Gurson-JC model

    Institute of Scientific and Technical Information of China (English)

    陆善彬; 周璐瑶; 郭赛

    2014-01-01

    T he basic sheet material fracture testing under different stress triaxialities and strain rates is carried out on specimens of low carbon steel Q 235 and aluminium alloy 6061T6 ,and the mechanical properties of these two materials under different working conditions are obtained .Six parameters of Gurson model are optimized by using LS-OPT software .This optimization method improves the effi-ciency in parameters determination and makes Gurson model applicable under a certain range of stress triaxiality .However ,Gurson model is incapable of predicting shear fracture under low stress triaxiali-ty .So an improved Gurson model with the strain failure criterion of Johnson-Cook model under low stress triaxiality is used to overcome this weakness under the shear working condition .Through the simulation and comparison of two materials under different stress triaxialities and strain rates by Gur-son model and Johnson-Cook model ,the relevant parameters of Gurson-JC model of the two materials are determined so as to satisfy the accuracy requirement under a wider range of stress triaxiality and strain rate .%文章对低碳钢Q235和铝合金6061T6试样在不同应力三轴度下进行拉伸试验,得到2种材料在不同工况下的力学性能。采用LS-OPT软件对Gurson模型相关参数进行优化,该优化方法既可以提高参数确定的效率,同时可以使Gurson模型在一定应力三轴度范围内适用。但Gurson模型不能准确预测在低应力三轴度下的失效,所以在低应力三轴度下引入Johnson-Cook模型的应变失效标准,以弥补剪切工况下的不足。通过比较Gurson模型和Johnson-Cook模型对2种材料在不同应力三轴度下的仿真结果,确定2种材料的Gurson-JC模型相关参数,以满足在较大范围内的应力三轴度下的仿真精准度。

  4. Decarbonising cities mainstreaming low carbon urban development

    CERN Document Server

    Rauland, Vanessa

    2015-01-01

    This book sets out some positive directions to move forward including government policy and regulatory options, an innovative GRID (Greening, Regenerative, Improvement Districts) scheme that can assist with funding and management, and the first steps towards an innovative carbon credit scheme for the built environment. Decarbonising cities is a global agenda with huge significance for the future of urban civilisation. Global demonstrations have shown that technology and design issues are largely solved. However, the mainstreaming of low carbon urban development, particularly at the precinct

  5. Experience and Ways of Low-carbon Agriculture Development

    Institute of Scientific and Technical Information of China (English)

    Xinmin; ZHANG; Chunhong; QIN

    2013-01-01

    Firstly,the status quo of low-carbon agriculture development in China was analyzed,and then advanced experience of developed countries in low-carbon agriculture development was introduced,finally ways of developing low-carbon agriculture in China were put forward.

  6. Standard Specification for Low-Carbon Nickel-Chromium-Molybdenum, Low-Carbon Nickel-Chromium-Molybdenum-Copper, Low-Carbon Nickel-Chromium-Molybdenum-Tantalum, Low-Carbon Nickel-Chromium-Molybdenum-Tungsten, and Low-Carbon Nickel-Molybdenum-Chromium Alloy Plate, Sheet, and Strip

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    Standard Specification for Low-Carbon Nickel-Chromium-Molybdenum, Low-Carbon Nickel-Chromium-Molybdenum-Copper, Low-Carbon Nickel-Chromium-Molybdenum-Tantalum, Low-Carbon Nickel-Chromium-Molybdenum-Tungsten, and Low-Carbon Nickel-Molybdenum-Chromium Alloy Plate, Sheet, and Strip

  7. Standard Specification for Low-Carbon Nickel-Chromium-Molybdenum, Low-Carbon Nickel-Molybdenum-Chromium, Low-Carbon Nickel-Molybdenum-Chromium-Tantalum, Low-Carbon Nickel-Chromium-Molybdenum-Copper, and Low-Carbon Nickel-Chromium-Molybdenum-Tungsten Alloy Rod

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    Standard Specification for Low-Carbon Nickel-Chromium-Molybdenum, Low-Carbon Nickel-Molybdenum-Chromium, Low-Carbon Nickel-Molybdenum-Chromium-Tantalum, Low-Carbon Nickel-Chromium-Molybdenum-Copper, and Low-Carbon Nickel-Chromium-Molybdenum-Tungsten Alloy Rod

  8. Approaches to Promote China's Low Carbon Agricultural Development%Approaches to Promote China's Low Carbon Agricultural Development

    Institute of Scientific and Technical Information of China (English)

    Chen Yao

    2012-01-01

    Low carbon agriculture is a new production mode of green agriculture development to face the challenge of the global climate change, and a kind of innovation on developing circular agriculture. Up to now, low carbon agricultural development approaches are lacking of deep and systematical researches. Therefore, the paper briefly analyzed the situation and the existing problems of China's low carbon agricultural development, and then put forward the approaches to promote the low carbon agricultural development.

  9. An economic assessment of low carbon vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Summerton, P. [Cambridge Econometrics CE, Cambridge (United Kingdom); Harrison, P. [European Climate Foundation ECF, Brussels (Belgium)] (eds.)

    2013-03-15

    The study aimed to analyse the economic impacts of decarbonizing light duty vehicles. As part of the study, the impacts of the European Commissions proposed 2020 CO2 regulation for cars and vans have been assessed. The analysis showed that a shift to low-carbon vehicles would increase spending on vehicle technology, therefore generating positive direct employment impacts, but potentially adding 1,000-1,100 euro to the capital cost of the average new car in 2020. However, these additional technology costs would be offset by fuel savings of around 400 euro per year, indicating an effective break-even point for drivers of approximately three years. At the EU level, the cost of running and maintaining the European car fleet would become 33-35 billion euro lower each year than in a 'do nothing scenario' by 2030, leading to positive economic impacts including indirect employment gains. Data on the cost of low carbon vehicle technologies has largely been sourced from the auto industry itself, with the study supported by a core working group including Nissan, GE, the European Association of Automotive Suppliers (CLEPA), and the European Storage Battery Manufacturers Association (Eurobat). Fuel price projections for the study were based on the IEA's World Energy Outlook, while technical modelling was carried out using the transport policy scoping tool SULTAN (developed by Ricardo-AEA for the European Commission) and the Road Vehicle Cost and Efficiency Calculation Framework, also developed by Ricardo-AEA. Macro-economic modelling was done using the E3ME model, which has previously been used for several European Commission and EU government impact assessments. This report focuses on efficient use of fossil fuels in internal combustion- and hybrid electric vehicles. It will be followed by a second report, which will focus on further reducing the use of fossil fuels by also substituting them with domestically produced energy carriers, such as electricity and

  10. Low carbon fuel and chemical production from waste gases

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, S.; Liew, F.M.; Daniell, J.; Koepke, M. [LanzaTech, Ltd., Auckland (New Zealand)

    2012-07-01

    LanzaTech has developed a gas fermentation platform for the production of alter native transport fuels and commodity chemicals from carbon monoxide, hydrogen and carbon dioxide containing gases. LanzaTech technology uses these gases in place of sugars as the carbon and energy source for fermentation thereby allowing a broad spectrum of resources to be considered as an input for product synthesis. At the core of the Lanzatech process is a proprietary microbe capable of using gases as the only carbon and energy input for product synthesis. To harness this capability for the manufacture of a diverse range of commercially valuable products, the company has developed a robust synthetic biology platform to enable a variety of novel molecules to be synthesised via gas fermentation. LanzaTech initially focused on the fermentation of industrial waste gases for fuel ethanol production. The company has been operating pilot plant that uses direct feeds of steel making off gas for ethanol production for over 24 months. This platform technology has been further successfully demonstrated using a broad range of gas inputs including gasified biomass and reformed natural gas. LanzaTech has developed the fermentation, engineering and control systems necessary to efficiently convert gases to valuable products. A precommercial demonstration scale unit processing steel mill waste gases was commissioned in China during the 2{sup nd} quarter of 2012. Subsequent scale-up of this facility is projected for the 2013 and will represent the first world scale non-food based low carbon ethanol project. More recently LanzaTech has developed proprietary microbial catalysts capable of converting carbon dioxide in the presence of hydrogen directly to value added chemicals, where-in CO{sub 2} is the sole source of carbon for product synthesis. Integrating the LanzaTech technology into a number of industrial facilities, such as steel mills, oil refineries and other industries that emit Carbon bearing

  11. How to Develop Low-carbon Agriculture in China?

    Institute of Scientific and Technical Information of China (English)

    Chengjun; ZHANG

    2015-01-01

    With the advent of low-carbon economy nowadays,the development of agriculture is necessary to adapt to the situation of global economic development,and transform the agricultural development models. This paper firstly gives an overview of low-carbon economy and lowcarbon agriculture,and then points out the possibility of developing the low-carbon agricultural economy in China,and describes the ways to develop the low-carbon agricultural economy. Finally,this paper puts forth the corresponding recommendations for the development of the lowcarbon agricultural economy.

  12. Low-carbon infrastructure strategies for cities

    Science.gov (United States)

    Kennedy, C. A.; Ibrahim, N.; Hoornweg, D.

    2014-05-01

    Reducing greenhouse gas emissions to avert potentially disastrous global climate change requires substantial redevelopment of infrastructure systems. Cities are recognized as key actors for leading such climate change mitigation efforts. We have studied the greenhouse gas inventories and underlying characteristics of 22 global cities. These cities differ in terms of their climates, income, levels of industrial activity, urban form and existing carbon intensity of electricity supply. Here we show how these differences in city characteristics lead to wide variations in the type of strategies that can be used for reducing emissions. Cities experiencing greater than ~1,500 heating degree days (below an 18 °C base), for example, will review building construction and retrofitting for cold climates. Electrification of infrastructure technologies is effective for cities where the carbon intensity of the grid is lower than ~600 tCO2e GWh-1 whereas transportation strategies will differ between low urban density (~6,000 persons km-2) cities. As nation states negotiate targets and develop policies for reducing greenhouse gas emissions, attention to the specific characteristics of their cities will broaden and improve their suite of options. Beyond carbon pricing, markets and taxation, governments may develop policies and target spending towards low-carbon urban infrastructure.

  13. Wood-burning stoves in low-carbon dwellings

    DEFF Research Database (Denmark)

    Luis Teles de Carvalho, Ricardo; Jensen, Ole Michael; Afshari, Alireza;

    2013-01-01

    The European climate change strategy intends to encourage the erection of low-carbon buildings and the upgrading of existing buildings to low-carbon level. At the same time, it is an EU vision to maximise the use of renewable energy resources. In this strategy, small-scale wood...

  14. From Green Building to Low Carbon Eco-City

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    After reviewing the development of energy-saving construction and green buildings in China,the author suggests that in order to develop low carbon cities in China,efforts should be put into both green buildings construction and low carbon ecologic city development.The paper divides the low-carbon ecologic cities into four categories and summarizes the experiences gained from the ecologic city development in Sino-Singapore Ecologic City in Tianjin and Caofeidian in Tangshan.In addition,it also introduces the general idea for low carbon city development in China and the particular requirements for the planning and construction,as well as the critical techniques for low carbon ecologic city development.

  15. Analysis on the Development of Low-Carbon Marine Economy

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    From the perspective of low-carbon economy,the paper analyzes the factors that influencing the development of low carbon economy.It is showed that the damage of marine ecological environment results in the low ability of oceans in absorbing green gas;environmental pollution leads to lowering capacity of ocean to deal with the wastes;development of related marine industries brings deterioration of marine environment;changes of climate threat the healthy development of marine economy.The paper points out the development routines of marine low carbon economy:accelerating the innovation of energy techniques,exploring marine renewable green energies;planning scientifically and strengthening the protection and repairmen of marine environment;developing marine recycle economy,upgrading resources using efficiency;adjusting marine industrial structures and exploring greatly the marine low carbon industries;guiding industries to chase chances and accelerating the development of low-carbon marine economy.

  16. Localized Corrosion of Chromium Coated Steel

    NARCIS (Netherlands)

    Zhang, X.; Beentjes, P.; Mol, A.; Terryn, H.

    2006-01-01

    In this paper, we report on the studies of the local corrosion behaviour of chromium-coated ultra low carbon steel in NaCl solution using polarization, electrochemical impedance spectroscopy (EIS) and SVET.

  17. FAW Technology Strategies of Low-Carbon Passenger Car

    Institute of Scientific and Technical Information of China (English)

    Li Jun

    2012-01-01

    Author analyzed the global background of low-carbon technology around the world,a technology & economy analysis model called TOS was developed in the paper,author analyzed technology paths for low-carbon Car in China based on the current technologies available and technologies to he developed in China,3 possible paths are presented based on the analysis,author also explained the FAW BlueWay technology strategies for low carbon cars both for short mid and long term objectives.Author concludes the paper with illustration of powertrain lineup for FAW BlueWay Technologies.

  18. Natural Gas Based Electricity Production and Low Carbon Technology Options

    Science.gov (United States)

    Concerns regarding air quality, global climate change, and the national energy security impacts of the intensive use of fossil fuels and their environmental impacts in the power generation sector have raised interest in alternative low carbon electricity generation technology and...

  19. Distributed Leadership in a Low-Carbon City Agenda

    Directory of Open Access Journals (Sweden)

    Azalia Mohamed

    2016-07-01

    Full Text Available This paper uses Spillane’s (2001 theory and Gronn’s (2000 concerted efforts approach to examine distributed leadership in a low-carbon city agenda. The main purpose of the paper is to find empirical evidence of a relationship between distributed leadership and the achievement of the agenda. Eight constructs emerged that informed our understanding of distributed leadership dimensions within the low-carbon city framework: vision, organizational framework, organizational culture, consensus, instructional programs, expertise, team leader leadership, and team member leadership. The evidence shows that there is a positive relationship between distributed leadership and the outcome of the low-carbon city agenda, and that a dispersed pattern in distributing leadership is required to enhance community engagement. The findings also suggest that an organizational culture that facilitates multiple sources of leadership may largely contribute to the effectiveness of distributed leadership practices in realizing the low-carbon city agenda.

  20. Renewable energy and low carbon economy transition in India

    DEFF Research Database (Denmark)

    Shukla, P.R.; Dhar, Subash; Fujino, Junichi

    2010-01-01

    Cooperation of large developing countries such as India would be important in achieving a low carbon future, which can help in restricting the global temperature rise to 2 °C. Global modeling studies of such low carbon scenarios point to a prominent role for renewable energy. This paper reports...... that aligns India’s emissions to an optimal 450 ppmv CO2-eq. stabilization global response. The second emissions pathway assumes an underlying sustainable development pattern. A low carbon future will be good for renewable energy under both the development pathways, though the share of renewable energy...... will be higher under a sustainable pathway. Renewable energy faces competition from low carbon technologies like nuclear and carbon capture and storage in the electricity sector. Solar, wind, biomass, and biofuels emerge as the four competitive renewable energy choices for India. Renewable development however...

  1. STUDY OF Mn AND P SOLUTE DISTRIBUTIONS AND THEIR EFFECT ON THE TENSILE BEHAVIOR IN ULTRA LOW CARBON BAKE HARDENING STEELS%Mn和P在超低碳烘烤硬化钢中的分布形态及其对拉伸行为的影响研究

    Institute of Scientific and Technical Information of China (English)

    王华; 史文; 何燕霖; 符仁钰; 李麟

    2011-01-01

    With the increasing requirement of vehicle weight reduction and energy conservation from automobile industry, the investigation and development of high strength steel sheet has been stressed extensively. Bake hardening steel, as a new kind of automotive steel, exhibits low strength and good formability before drawing, after which increases obviously in the yield strength during baking process, and is then widely used in the outer plate of modern cars. Mn and P are often added to sheet steel to increase the strength, and their distributions have significant effect on drawability,bake hardening property and surface quality of bake hardening steels. In this paper, the distributions of Mn and P and their effect on tensile behavior in bake hardening steels were studied. For investigation,two kinds of bake hardening steels (BH-Mn and BH-P steels) were heated to 800 ℃, held for 2 min and cooled by water quenching. Three dimensional atom probe (3DAP) technique, internal friction experiments and tensile tests were carried out to analysis the effect of Mn and P distribution patterns on the interstitial atom distribution and Cottrell atmosphere in the matrix, so as to obtain the influence of solute distributions on tensile behavior. The results indicate that P segregates mainly in bake hardening steel, and part of P segregates together with C, which strongly pin the dislocations and is the main reason that induces the yield point elongation during tensile process. In BH-Mn steel,Mn hardly segregates in the matrix and C segregates very little, so the strength of BH-Mn steel is lower than that of BH-P steel, whereas the plasticity is better than BH-P steel. The segregation of P together with C and its pinning of dislocations will influence Snoek -Ke-Koster internal friction, and makes the disappearance of Snoek-Ke-Koster peak.%将2种不同成分的烘烤硬化钢(BH-Mn钢和BH-P钢)加热至800℃,保温2 min后水淬;采用3DAP技术、内耗实验及拉伸性能检测分

  2. Investigation of Corrosion and Cathodic Protection in Reinforced Concrete. II: Properties of Steel Surface Layers

    NARCIS (Netherlands)

    Koleva, D.A.; De Wit, J.H.W.; Van Breugel, K.; Lodhi, Z.F.; Ye, G.

    2007-01-01

    The present study explores the formation of corrosion products on the steel surface (using as-received low carbon construction steel) in reinforced concrete in conditions of corrosion and subsequent transformation of these layers in conditions of cathodic protection (CP).

  3. Nested barriers to low-carbon infrastructure investment

    Science.gov (United States)

    Granoff, Ilmi; Hogarth, J. Ryan; Miller, Alan

    2016-12-01

    Low-carbon, 'green' economic growth is necessary to simultaneously improve human welfare and avoid the worst impacts of climate change and environmental degradation. Infrastructure choices underpin both the growth and the carbon intensity of the economy. This Perspective explores the barriers to investing in low-carbon infrastructure and some of the policy levers available to overcome them. The barriers to decarbonizing infrastructure 'nest' within a set of barriers to infrastructure development more generally that cause spending on infrastructure--low-carbon or not--to fall more than 70% short of optimal levels. Developing countries face additional barriers such as currency and political risks that increase the investment gap. Low-carbon alternatives face further barriers, such as commercialization risk and financial and public institutions designed for different investment needs. While the broader barriers to infrastructure investment are discussed in other streams of literature, they are often disregarded in literature on renewable energy diffusion or climate finance, which tends to focus narrowly on the project costs of low- versus high-carbon options. We discuss how to overcome the barriers specific to low-carbon infrastructure within the context of the broader infrastructure gap.

  4. The Deployment of Low Carbon Technologies in Energy Intensive Industries: A Macroeconomic Analysis for Europe, China and India

    Directory of Open Access Journals (Sweden)

    Stefan Nabernegg

    2017-03-01

    Full Text Available Industrial processes currently contribute 40% to global CO2 emissions and therefore substantial increases in industrial energy efficiency are required for reaching the 2 °C target. We assess the macroeconomic effects of deploying low carbon technologies in six energy intensive industrial sectors (Petroleum, Iron and Steel, Non-metallic Minerals, Paper and Pulp, Chemicals, and Electricity in Europe, China and India in 2030. By combining the GAINS technology model with a macroeconomic computable general equilibrium model, we find that output in energy intensive industries declines in Europe by 6% in total, while output increases in China by 11% and in India by 13%. The opposite output effects emerge because low carbon technologies lead to cost savings in China and India but not in Europe. Consequently, the competitiveness of energy intensive industries is improved in China and India relative to Europe, leading to higher exports to Europe. In all regions, the decarbonization of electricity plays the dominant role for mitigation. We find a rebound effect in China and India, in the size of 42% and 34% CO2 reduction, respectively, but not in Europe. Our results indicate that the range of considered low-carbon technology options is not competitive in the European industrial sectors. To foster breakthrough low carbon technologies and maintain industrial competitiveness, targeted technology policy is therefore needed to supplement carbon pricing.

  5. Low Carbon Supplier Selection in the Hotel Industry

    Directory of Open Access Journals (Sweden)

    Chia-Wei Hsu

    2014-05-01

    Full Text Available This study presents a model for evaluating the carbon and energy management performance of suppliers by using multiple-criteria decision-making (MCDM. By conducting a literature review and gathering expert opinions, 10 criteria on carbon and energy performance were identified to evaluate low carbon suppliers using the Fuzzy Delphi Method (FDM. Subsequently, the decision-making trial and evaluation laboratory (DEMATEL method was used to determine the importance of evaluation criteria in selecting suppliers and the causal relationships between them. The DEMATEL-based analytic network process (DANP and VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR were adopted to evaluate the weights and performances of suppliers and to obtain a solution under each evaluation criterion. An illustrative example of a hotel company was presented to demonstrate how to select a low carbon supplier according to carbon and energy management. The proposed hybrid model can help firms become effective in facilitating low carbon supply chains in hotels.

  6. Counting the cost of carbon. Low carbon economy index 2011

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-15

    Achieving the rates of decarbonisation needed to stay within the 2 degrees target agreed by governments in Cancun in 20101 requires a revolution in the way the world produces and uses energy. A transformation in financing will also be necessary to achieve the transition at the scale and speed needed. PwC published the first Low Carbon Economy Index ahead of the COP15 in Copenhagen, 2009. This looked at the progress of the G20 economies against a 2000-based carbon budget estimated by PwC. Carbon intensity is our preferred metric for analysing countries' movements towards a low carbon economy, as it accounts for expected economic growth, and can generate comparable targets. The carbon intensity of an economy is the emissions per unit of GDP and is affected by a country's fuel mix, energy efficiency and the proportion of industrial versus service sectors. Since COP 16 in Cancun, there has been an increasing focus on the cost of meeting the low carbon challenge and raising the capital required to finance it. This year's Low Carbon Economy Index focuses on this global financing gap and the reforms that might help to fill it. In section one we present our analysis of economic and emissions growth and ask whether we are decarbonising fast enough. The second section asks how much it will cost and can we afford it. We highlight the global financing gap, and focus on efforts to increase low carbon generation in the UK and South Africa. The report concludes by outlining some steps that could be taken to help meet the low carbon challenge.

  7. Global low-carbon transition and China's response strategies

    Directory of Open Access Journals (Sweden)

    Jian-Kun He

    2016-12-01

    Full Text Available The Paris Agreement establishes a new mechanism for post-2020 global climate governance, and sets long-term goals for global response to climate change, which will accelerate worldwide low-carbon transformation of economic development pattern, promote the revolutionary reform of energy system, boost a fundamental change in the mode of social production and consumption, and further the civilization of human society from industrial civilization to eco-civilization. The urgency of global low-carbon transition will reshape the competition situation of world's economy, trade and technology. Taking the construction of eco-civilization as a guide, China explores green and low-carbon development paths, establishes ambitious intended nationally determined contribution (INDC targets and action plans, advances energy production and consumption revolution, and speeds up the transformation of economic development pattern. These strategies and actions not only confirm to the trend of the world low-carbon transition, but also meet the intrinsic requirements for easing the domestic resources and environment constraints and realizing sustainable development. They are multi-win-win strategies for promotion of economic development and environmental protection and mitigation of carbon emissions. China should take the global long-term emission reduction targets as a guide, and formulate medium and long-term low-carbon development strategy, build the core competitiveness of low-carbon advanced technology and development pattern, and take an in-depth part in global governance so as to reflect the responsibility of China as a great power in constructing a community of common destiny for all mankind and addressing global ecological crisis.

  8. China Aims to Boost Emerging Industries for Low Carbon Economy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ China is making concrete steps in pushing forward with its low-carbon economy by boosting strategic emerging industries at home.The Chinese government will guido the development of high-tech industries such as wind and solar power equipment manufacturing as China rushed to build a low-carbon economy.In December 2009,Chinese Premier Wen Jiabao listed seven high-tech emerging industries as new energy,energy-saving and environmental protection,electric vehicles,new materials,information industry,new medicine and pharmacology,as well as biological breeding.

  9. Development of Advanced High Strength Steel for Improved Vehicle Safety, Fuel Efficiency and CO2 Emission

    Science.gov (United States)

    Kumar, Satendra; Singhai, Mrigandra; Desai, Rahul; Sam, Srimanta; Patra, Pradip Kumar

    2016-10-01

    Global warming and green house gas emissions are the major issues worldwide and their impacts are clearly visible as a record high temperatures, rising sea, and severe `flooding and droughts'. Motor vehicles considered as a major contributor on global warming due to its green house gas emissions. Hence, the automobile industries are under tremendous pressure from government and society to reduce green house gas emission to maximum possible extent. In present work, Dual Phase steel with boron as microalloying is manufactured using thermo-mechanical treatment during hot rolling. Dual phase steel with boron microalloying improved strength by near about 200 MPa than dual phase steel without boron. The boron added dual phase steel can be used for manufacturing stronger and a lighter vehicle which is expected to perform positively on green house gas emissions. The corrosion resistance behavior is also improved with boron addition which would further increase the life cycle of the vehicle even under corrosive atmosphere.

  10. Development of Advanced High Strength Steel for Improved Vehicle Safety, Fuel Efficiency and CO2 Emission

    Science.gov (United States)

    Kumar, Satendra; Singhai, Mrigandra; Desai, Rahul; Sam, Srimanta; Patra, Pradip Kumar

    2015-12-01

    Global warming and green house gas emissions are the major issues worldwide and their impacts are clearly visible as a record high temperatures, rising sea, and severe `flooding and droughts'. Motor vehicles considered as a major contributor on global warming due to its green house gas emissions. Hence, the automobile industries are under tremendous pressure from government and society to reduce green house gas emission to maximum possible extent. In present work, Dual Phase steel with boron as microalloying is manufactured using thermo-mechanical treatment during hot rolling. Dual phase steel with boron microalloying improved strength by near about 200 MPa than dual phase steel without boron. The boron added dual phase steel can be used for manufacturing stronger and a lighter vehicle which is expected to perform positively on green house gas emissions. The corrosion resistance behavior is also improved with boron addition which would further increase the life cycle of the vehicle even under corrosive atmosphere.

  11. Funding pathways to a low-carbon transition

    Science.gov (United States)

    Foulds, Chris; Christensen, Toke Haunstrup

    2016-07-01

    The framing of funding programmes can sustain existing ways of conceptualizing particular problems, as well as create new ones. Yet, without more prominent roles for social sciences and humanities, the techno-economic conceptualization of energy consumers could hinder long-term low-carbon aspirations.

  12. Developing low carbon policies for road transport in Poland

    NARCIS (Netherlands)

    Kok, R.; Rahman, S.A.

    2010-01-01

    This paper presents the results of work done for the World Bank to develop low carbon policies for road transport in Poland. Here, we outline the development of Green House Gas (GHG) emissions, develop a Business As Usual (BAU) scenario based on social-economic-, infrastructure-, car market, vehicle

  13. Development of a New Armor Steel and its Ballistic Performance

    Directory of Open Access Journals (Sweden)

    S. Hakan Atapek

    2013-05-01

    Full Text Available In this study, a boron added armor steel was developed according to standard rolled homogenous armor steel, MIL-A-12560, and metallographic-fractographic examinations were carried out to understand its deformation characteristics and perforation mode after interaction with a 7.62 mm armor piercing projectile. The microstructure of the developed steel was characterized by light and scanning electron microscope to evaluate its matrix after application of several heat treatments consisting of austenization, quenching and tempering. The mechanical properties of the developed steel were determined by tensile test at room temperature and notched impact test at -40 ºC. The ballistic performance of developed steel was determined by its V50 ballistic protection limit according to MIL-STD-662F standard and it was found to be higher than that of MIL-A-12560 steel. After perforation deformation induced adiabatic shear bands, that have an important role on the crack nucleation, were observed close to the penetration in the etched steel and perforation occurred by typical ductile hole enlargement with certain radial flows.Defence Science Journal, 2013, 63(3, pp.271-277, DOI:http://dx.doi.org/10.14429/dsj.63.1341

  14. Operation Mechanism of Farmers’ Professional Cooperatives from the Point of Low-Carbon Agricultural Products

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    We firstly take a look at internal logic of cluster development of low-carbon agricultural products.In combination with operation features of farmers’ professional cooperatives and actual requirements for cluster development of low-carbon agricultural products;we elaborate establishing benefit allocation mechanism,bearing education and training functions,forming low-carbon value,building low-carbon identification system,as well as realizing low-carbon value.According to these situations,we systematically analyze operation mechanism of farmers’ professional cooperatives suitable for cluster development of low-carbon agricultural products.To promote cluster development of low-carbon agricultural products,we put forward following suggestions,including government guidance and encouragement,social acceptance and active cooperation,and integration into global low-carbon development system to share benefit of low-carbon development.

  15. Fusion power in a future low carbon global electricity system

    DEFF Research Database (Denmark)

    Cabal, H.; Lechón, Y.; Bustreo, C.

    2017-01-01

    Fusion is one of the technologies that may contribute to a future, low carbon, global energy supply system. In this article we investigate the role that it may play under different scenarios. The global energy model ETM (originally EFDA TIMES Model) has been used to analyse the participation of f....... Finally, the main competitors for fusion in future are Carbon Capture and Storage and fission technologies.......Fusion is one of the technologies that may contribute to a future, low carbon, global energy supply system. In this article we investigate the role that it may play under different scenarios. The global energy model ETM (originally EFDA TIMES Model) has been used to analyse the participation...

  16. Possibilities and Challenges designing low-carbon-energy technologies

    DEFF Research Database (Denmark)

    Bjarklev, Araceli

    Footprint, concepts and tools from Life Cycle Assessment, and relevant elements from eco-efficiency theoretical frameworks. Often systemic approaches tend to be driven by completely rational models. However, our main contribution is to consider a more holistic approach that also includes socio......Though there is broad consensus that one of the solutions to the current environmental challenge will be based on the use of low-carbon technologies, and even though there is a big potential to turn to a more sustainable design and innovation, there are several elements that need to be taken...... as a study object and discusses the question: What are the main possibilities and challenges when designing low-carbon illumination technologies? To answer this question, we use a systemic approach including environmental, economic, energy and political issues using relevant concepts from the Ecological...

  17. Developmental Status Quo and Trends of Low-carbon Agriculture

    Institute of Scientific and Technical Information of China (English)

    Liming; CAO; Xiaohua; PAN; Maobai; LI

    2013-01-01

    In order to reduce carbon emission in agricultural production,this paper has discussed the developmental trends of low-carbon agriculture in terms of developing precision agriculture,improving the efficiency of fertilizer utilization,scientific use of pesticides,water-saving irrigation,ecological control of pests and diseases,as well as energy conservation and emission reduction by agricultural machinery and other agricultural practices.

  18. China Aims to Boost Emerging Industries for Low Carbon Economy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ China has made significant efforts to pursue energy and resource efficieneies to achieve sustainable development,while the nation still faces challenges in the transition to a low-carbon economy and needs integrated solution systems.Changing energy use is the biggest of China's challenges when transforming to a green economy.China's explosive industrial development has placed great pressure on the consumption of energy and other resources.

  19. Low -carbon life%低碳生活

    Institute of Scientific and Technical Information of China (English)

    段溶

    2012-01-01

    什么是低碳生活? 低碳生活意味着要减少二氧化碳的排放,是一种低能量、低消耗、低开支的生活方式。%What's the low-carbon life? Lowcarbon life is a kind of life style with low energy, low consumption and low cost of living which means reducing carbon dioxide emissions.

  20. Health benefits, ecological threats of low-carbon electricity

    Science.gov (United States)

    Gibon, Thomas; Hertwich, Edgar G.; Arvesen, Anders; Singh, Bhawna; Verones, Francesca

    2017-03-01

    Stabilizing global temperature will require a shift to renewable or nuclear power from fossil power and the large-scale deployment of CO2 capture and storage (CCS) for remaining fossil fuel use. Non-climate co-benefits of low-carbon energy technologies, especially reduced mortalities from air pollution and decreased ecosystem damage, have been important arguments for policies to reduce CO2 emissions. Taking into account a wide range of environmental mechanisms and the complex interactions of the supply chains of different technologies, we conducted the first life cycle assessment of potential human health and ecological impacts of a global low-carbon electricity scenario. Our assessment indicates strong human health benefits of low-carbon electricity. For ecosystem quality, there is a significant trade-off between reduced pollution and climate impacts and potentially significant ecological impacts from land use associated with increased biopower utilization. Other renewables, nuclear power and CCS show clear ecological benefits, so that the climate mitigation scenario with a relatively low share of biopower has lower ecosystem impacts than the baseline scenario. Energy policy can maximize co-benefits by supporting other renewable and nuclear power and developing biomass supply from sources with low biodiversity impact.

  1. Low Carbon Footprint Mortar from Pozzolanic Waste Material

    Directory of Open Access Journals (Sweden)

    Taha Mehmannavaz

    2014-04-01

    Full Text Available Nowadays, Portland cement clinker leads to emission of CO2 into the atmosphere and therefore causes greenhouse effect. Incorporating of Palm Oil Fuel Ash (POFA and Pulverized Fuel Ash (PFA as partial cement replacement materials into mix of low carbon mortar decreases the amount of cement use and reduces high dependence on cements compared to ordinary mortar. The result of this research supported use of the new concept in preparing low carbon mortar for industrial constructions. Strength of low carbon mortar with POFA and PFA replacement in cement was affected and changed by replacing percent finesse, physical and chemical properties and pozzolanic activity of these wastes. Waste material replacement instead of Ordinary Portland Cement (OPC was used in this study. This in turn was useful for promoting better quality of construction and innovative systems in construction industry, especially in Malaysia. This study was surely a step forward to achieving quality products which were affordable, durable and environmentally friendly. Disposing ash contributes to shortage of landfill space in Malaysia. Besides, hazard of ash might be another serious issue for human health. The ash disposal area also might create a new problem, which is the area's sedimentation and erosion.

  2. Analysis on the deformation and fracture behavior of carbon steel by in situ tensile test

    Institute of Scientific and Technical Information of China (English)

    Fan Li; Haibo Huang

    2006-01-01

    The deformation and fracture behaviors of low-carbon steel, medium-carbon steel, and high-carbon steel were studied on internal microstructure using the scanning electron microscopy in situ tensile test. The microstructure mechanism of their deformation and fracture behavior was analyzed. The results show that the deformation and fracture behavior of low-carbon steel depends on the grain size of ferrite, the deformation and fracture behavior of medium-carbon steel depends on the size of ferrite grain and pearlite lump,and the deformation and fracture behavior of high-carbon steel depends on the size of pearlite lump and the pearlitic interlamellar spacing.

  3. Fracture Mechanisms in Steel Castings

    Directory of Open Access Journals (Sweden)

    Z. Stradomski

    2013-07-01

    Full Text Available The investigations were inspired with the problem of cracking of steel castings during the production process. A single mechanism of decohesion - the intergranular one - occurs in the case of hot cracking, while a variety of structural factors is decisive for hot cracking initiation, depending on chemical composition of the cast steel. The low-carbon and low-alloyed steel castings crack due to the presence of the type II sulphides, the cause of cracking of the high-carbon tool cast steels is the net of secondary cementite and/or ledeburite precipitated along the boundaries of solidified grains. Also the brittle phosphor and carbide eutectics precipitated in the final stage solidification are responsible for cracking of castings made of Hadfield steel. The examination of mechanical properties at 1050°C revealed low or very low strength of high-carbon cast steels.

  4. Study on environmental cost accounting under low-carbon economy

    Science.gov (United States)

    Pei, Zhoukun

    2017-03-01

    With the strengthen of people's ability to use and transform nature, on the one hand, people acquire more resources from nature and make life more comfortable, on the other hand, the amount of waste that people emit has also increased rapidly. Excessive excavation of resources and disposal of waste emissions led to the deterioration of the environment, affecting the country's sustainable development and the Earth's ecological balance. In this paper, from the perspective of low-carbon economy, to explore corporate environmental cost recognition, measurement, collection, distribution methods, expectations for the relevant enterprises, especially high-polluting, high-emission energy-based enterprises to learn from.

  5. Supply chains and energy security in a low carbon transition

    OpenAIRE

    Hoggett, Richard; Bolton, Ronan; Candelise, Chiara; Kern, Florian; Mitchell, Catherine; Yan, Jinyue

    2014-01-01

    This special edition to be published in Applied Energy brings together a range of papers that explore the complex, multi-dimensional and inter-related issues associated with the supply or value chains that make up energy systems and how a focus on them can bring new insights for energy security in a low carbon transition.\\ud \\ud Dealing with the trilemma of maintaining energy security, reducing greenhouse gas emissions and maintaining affordability for economies and end users are key issues f...

  6. Funding pathways to a low-carbon transition

    DEFF Research Database (Denmark)

    Foulds, Chris; Christensen, Toke Haunstrup

    2016-01-01

    The framing of funding programmes can sustain existing ways of conceptualizing particular problems, as well as create new ones. Yet, without more prominent roles for social sciences and humanities, the techno-economic conceptualization of energy consumers could hinder long-term low-carbon aspirat......The framing of funding programmes can sustain existing ways of conceptualizing particular problems, as well as create new ones. Yet, without more prominent roles for social sciences and humanities, the techno-economic conceptualization of energy consumers could hinder long-term low...

  7. Seoul: Public policies to walk through a low carbon era

    Directory of Open Access Journals (Sweden)

    Silvia Guadalupe Figueroa González

    2013-06-01

    Full Text Available The economic and demographic growth that Seoul has experienced in recent decades has led to an increase in demand and energy consumption at the expense of the environment. In accordance with national green growth vision, Seoul is implementing a number of strategies that involve various actors for the transition to a low carbon era. The paper addresses Korea’s vision for green growth, analyzes presidential leadership to articulate policies in the domestic and international level and the actions executed locally by the Seoul Metropolitan Government.

  8. Key Assets for a Sustainable Low Carbon Energy Future

    Science.gov (United States)

    Carre, Frank

    2011-10-01

    Since the beginning of the 21st century, concerns of energy security and climate change gave rise to energy policies focused on energy conservation and diversified low-carbon energy sources. Provided lessons of Fukushima accident are evidently accounted for, nuclear energy will probably be confirmed in most of today's nuclear countries as a low carbon energy source needed to limit imports of oil and gas and to meet fast growing energy needs. Future challenges of nuclear energy are then in three directions: i) enhancing safety performance so as to preclude any long term impact of severe accident outside the site of the plant, even in case of hypothetical external events, ii) full use of Uranium and minimization long lived radioactive waste burden for sustainability, and iii) extension to non-electricity energy products for maximizing the share of low carbon energy source in transportation fuels, industrial process heat and district heating. Advanced LWRs (Gen-III) are today's best available technologies and can somewhat advance nuclear energy in these three directions. However, breakthroughs in sustainability call for fast neutron reactors and closed fuel cycles, and non-electric applications prompt a revival of interest in high temperature reactors for exceeding cogeneration performances achievable with LWRs. Both types of Gen-IV nuclear systems by nature call for technology breakthroughs to surpass LWRs capabilities. Current resumption in France of research on sodium cooled fast neutron reactors (SFRs) definitely aims at significant progress in safety and economic competitiveness compared to earlier reactors of this type in order to progress towards a new generation of commercially viable sodium cooled fast reactor. Along with advancing a new generation of sodium cooled fast reactor, research and development on alternative fast reactor types such as gas or lead-alloy cooled systems (GFR & LFR) is strategic to overcome technical difficulties and/or political

  9. A Low Carbon Development Strategy with Chinese Characteristics

    Institute of Scientific and Technical Information of China (English)

    WANG Yi

    2009-01-01

    @@ Now one of the world largest CO2 emitters, China faces increasing pressure to reduce its emissions. Being a responsible country, it will take action to tackle climate change. When developing its mitigation target, China will consider such factors as the levels of development and technology know-how, social impacts, international image and a new international climate regime underpinned by fairness and effectiveness. China will move onto a win-win low carbon development path to achieve climate protection, quality economic development and other related policy targets.

  10. Local hardening evaluation of carbon steels by using frequency sweeping excitation and spectrogram method

    Science.gov (United States)

    Tsuchida, Yuji; Kudo, Yuki; Enokizono, Masato

    2017-02-01

    This paper presents our proposed frequency sweeping excitation and spectrogram method (FSES method) by a magnetic sensor for non-destructive testing of hardened low carbon steels. This method can evaluate the magnetic properties of low carbon steels which were changed after induction heating treatment. It was examined by our proposed method that the degrees of yield strength of low carbon steels were varied depending on hardened conditions. Moreover, it was made clear that the maximum magnetic field strength, Hmax, derived from the measured B-H loops was very sensitive to the hardening if the surface of the samples were flat.

  11. 低C含Cu NV-F690特厚钢板的精细组织和强韧性%FINE MICROSTRUCTURE AND TOUGHNESS OF LOW CARBON COPPER CONTAINING ULTRA HIGH STRENGTH NV-F690 HEAVY STEEL PLATE

    Institute of Scientific and Technical Information of China (English)

    刘东升; 程丙贵; 陈圆圆

    2012-01-01

    本文通过板坯连铸、钢板控轧控冷(TMCP)、固溶淬火回火(QT)工业生产流程,开发低C含Cu高强韧NV-F690特厚(厚度t为80 mm)船体和海洋平台用钢板,使用SEM,EBSD和TEM分别研究了淬火(Q)态和QT态钢板的精细组织,测试了距离钢板表面t/4处(高冷却速率)和芯部t/2处(低冷却速率)的室温硬度和拉伸性能,在-60和-80℃下进行了Charpy冲击(Charpy V notch,CVN)示波实验.结果表明,淬火速率较大有利于板条组织形成和提高大角度晶界比例,t/4处的组织为板条状贝氏体(LB),板条间存在细小片状马氏体/奥氏体(M/A)组元,晶粒间大角度晶界(>15°)体积分数为67.5%;t/2处的组织为粒状贝氏体(GB)+LB.大角度晶界体积分数为63.0%;Q态下的LB具有高位错密度,但晶粒内不存在Cu析出相.经过650℃回火150 min,钢板的强韧性匹配优良,低温下呈韧性断裂,大量含Cu弥散沉淀相在基体组织内析出.t/2处的M/A组元分解为Cr-Mo碳化物,贝氏体板条宽度为0.4 μm,大角度晶界分数为62.5%; t/4处的LB板条回复,板条内存在与基体取向差较大的亚晶,大角度晶界分数提高到71.7%,板条平均宽度为0.2 μm.在-80℃下,NV-F690钢板t/4处的韧性高于t/2处的韧性.随着纤维断裂位移的增大,韧窝断裂区比例和韧窝尺寸逐渐增大,NV-F690钢低温Charpy冲击能量逐渐提高.%Advanced NV-F690 heavy steel plates for offshore structure and shipbuilding have been produced via continuous casting of the slab, thermomechanical control rolling of the plate followed by solutionizing (austenitizing), quenching and tempering (QT) steps. The present work is to reveal the microstructure evolution and evaluate the mechanical properties of 80 mm thick plates subjected to the QT process. The microstructures were characterized with SEM, EBSD and TEM. At quarter thickness (f/4) where the cooling rate was rapid, the as quenched microstructures consist of mainly lath

  12. Research of low-carbon transition path of star hotels--A case study of Guilin

    Directory of Open Access Journals (Sweden)

    Tang Fengling

    2016-01-01

    Full Text Available A general trend of the world economic development is the low-carbon economic transition. With a wide influencing range and rapid development, the hotel industry has prominent problems in the energy con-sumption, resources occupancy and environmental unfriendliness, so it is imperative to develop low-carbon ho-tels. This paper proposes the low-carbon transition of the star hotels in Guilin in terms of constructing the energy conservation and innovative management mode, adopting new technologies and ways, developing low-carbon hotel products and guiding low-carbon consumption through analysis about the inevitability of establishing low-carbon hotels in Guilin, the running status of the existing star hotels and the situation of energy consumption, thus further promoting the development of low-carbon tourism in Guilin.

  13. Energy modelling towards low carbon development of Beijing in 2030

    DEFF Research Database (Denmark)

    Zhao, Guangling; Guerrero, Josep M.; Jiang, Kejun;

    2017-01-01

    Beijing, as the capital of China, is under the high pressure of climate change and pollution. The consumption of non-renewable energy is one of the most important sources of the CO2 emissions, which cause climate changes. This paper presents a study on the energy system modelling towards renewable...... energy and low carbon development for the city of Beijing. The analysis of energy system modelling is organized in two steps to explore the alternative renewable energy system in Beijing. Firstly, a reference energy system of Beijing is created based on the available data in 2014. The Energy......PLAN, an energy system analysis tool, is chosen to develop the reference energy model. Secondly, this reference model is used to investigate the alternative energy system for integrating renewable energies. Three scenarios are developed towards the energy system of Beijing in 2030, which are: (i) reference...

  14. Low Carbon Energy Supply for South East Europe

    DEFF Research Database (Denmark)

    Dominkovic, Dominik Franjo; Bačeković, I.; Ćosić, B.

    2015-01-01

    South East Europe consists of several smaller countries in terms of energy systems and thus,integrating energy systems of the whole region has significant benefits for all the countries included. However, as there are large differences between energy mixes of the countries included, careful energy...... planning needs to be carried out in order to satisfy energy needs of all the countries of the region.Due to the significant differences in geography and the climate of different parts of the region, many different technologies need to be introduced in order to have optimal, low-carbon energy mix.......In this paper, steps toward the 100% renewable energy system (RES) for the year 2050 have been presented. Novelty in this paper, compared to the similar research already being carried out, is the sustainable use of biomass in 100% RES, as this is the only way in which biomass can be considered as carbon...

  15. Introduction to low-carbon innovation and development

    DEFF Research Database (Denmark)

    Lema, Rasmus; Iizuka, Michiko; Walz, Rainer

    2015-01-01

    This special issue seeks to bring together the fields of low-carbon development (LCD) and innovation studies. It contributes to the debate by addressing how the learning, innovation, and competence-building lens adds to the discussion about the development outcomes of climate change mitigation....... The aim of this introductory article is fourfold. First, it discusses key advances in the debate about the role of innovation and competence building in LCD in developing countries. Second, it seeks to add to the debate by paying particular attention to the heterogeneity of developing countries in terms...... of the context and innovative capacity for LCD. Third, it addresses the challenges to policy arising from such differentiated starting points. Finally, it sets forth the insights from the articles in this issue and the implications for future research....

  16. Walking away from a low-carbon economy?

    DEFF Research Database (Denmark)

    Mundaca T., Luis; Markandya, Anil; Nørgaard, Jørgen

    2013-01-01

    Using the latest available data, this brief article attempts to provide the first regional decomposition analysis of CO2 emissions from fuel combustion. Covering eight regions of the world, determinants are estimated in relative and absolute terms for the period 1971–2010. We use the unparalleled...... of continuous improvement (e.g. reduced energy intensity in Asia, decarbonisation of of energy supply in OECD Europe), they are incapable of offsetting the effects of economic growth and increased energy use. With the exception of Africa, most regions appear to have missed the ‘low-carbon economy opportunity......’ provided by the 2008–2009 global financial crisis. Results suggest a lack of serious environmental effectiveness of regional policy portfolios aiming at reducing CO2 emissions. Highly ambitious energy efficiency and renewable energy policies across all regions are immediately needed. Additionally, absolute...

  17. Energy policies for low carbon sustainable transport in Asia

    DEFF Research Database (Denmark)

    Shukla, P.R.; Dhar, Subash

    2015-01-01

    equivalent to 2 °C stabilization. Accounting for heterogeneity of national transport systems, these papers use diverse methods, frameworks and models to assess the response of the transport system to environmental policy, such as a carbon tax, as well as to a cluster of policies aimed at diverse development...... indicators. The analysis shows that CO2 mitigation in a transport system is achieved more effectively by aligning mitigation policies with sustainable development policies and measures such as mandates for mode share and choices such as urban design, information and communication systems, and behavioral......Transformation of Asia's transport sector has vital implications for climate change, sustainable development and energy indicators. Papers in this special issue show how transport transitions in Asia may play out in different socio-economic and policy scenarios, including a low carbon scenario...

  18. Jellyfish body plans provide allometric advantages beyond low carbon content.

    Directory of Open Access Journals (Sweden)

    Kylie A Pitt

    Full Text Available Jellyfish form spectacular blooms throughout the world's oceans. Jellyfish body plans are characterised by high water and low carbon contents which enables them to grow much larger than non-gelatinous animals of equivalent carbon content and to deviate from non-gelatinous pelagic animals when incorporated into allometric relationships. Jellyfish have, however, been argued to conform to allometric relationships when carbon content is used as the metric for comparison. Here we test the hypothesis that differences in allometric relationships for several key functional parameters remain for jellyfish even after their body sizes are scaled to their carbon content. Data on carbon and nitrogen contents, rates of respiration, excretion, growth, longevity and swimming velocity of jellyfish and other pelagic animals were assembled. Allometric relationships between each variable and the equivalent spherical diameters of jellyfish and other pelagic animals were compared before and after sizes of jellyfish were standardised for their carbon content. Before standardisation, the slopes of the allometric relationships for respiration, excretion and growth were the same for jellyfish and other pelagic taxa but the intercepts differed. After standardisation, slopes and intercepts for respiration were similar but excretion rates of jellyfish were 10× slower, and growth rates 2× faster than those of other pelagic animals. Longevity of jellyfish was independent of size. The slope of the allometric relationship of swimming velocity of jellyfish differed from that of other pelagic animals but because they are larger jellyfish operate at Reynolds numbers approximately 10× greater than those of other pelagic animals of comparable carbon content. We conclude that low carbon and high water contents alone do not explain the differences in the intercepts or slopes of the allometric relationships of jellyfish and other pelagic animals and that the evolutionary longevity

  19. Jellyfish body plans provide allometric advantages beyond low carbon content.

    Science.gov (United States)

    Pitt, Kylie A; Duarte, Carlos M; Lucas, Cathy H; Sutherland, Kelly R; Condon, Robert H; Mianzan, Hermes; Purcell, Jennifer E; Robinson, Kelly L; Uye, Shin-Ichi

    2013-01-01

    Jellyfish form spectacular blooms throughout the world's oceans. Jellyfish body plans are characterised by high water and low carbon contents which enables them to grow much larger than non-gelatinous animals of equivalent carbon content and to deviate from non-gelatinous pelagic animals when incorporated into allometric relationships. Jellyfish have, however, been argued to conform to allometric relationships when carbon content is used as the metric for comparison. Here we test the hypothesis that differences in allometric relationships for several key functional parameters remain for jellyfish even after their body sizes are scaled to their carbon content. Data on carbon and nitrogen contents, rates of respiration, excretion, growth, longevity and swimming velocity of jellyfish and other pelagic animals were assembled. Allometric relationships between each variable and the equivalent spherical diameters of jellyfish and other pelagic animals were compared before and after sizes of jellyfish were standardised for their carbon content. Before standardisation, the slopes of the allometric relationships for respiration, excretion and growth were the same for jellyfish and other pelagic taxa but the intercepts differed. After standardisation, slopes and intercepts for respiration were similar but excretion rates of jellyfish were 10× slower, and growth rates 2× faster than those of other pelagic animals. Longevity of jellyfish was independent of size. The slope of the allometric relationship of swimming velocity of jellyfish differed from that of other pelagic animals but because they are larger jellyfish operate at Reynolds numbers approximately 10× greater than those of other pelagic animals of comparable carbon content. We conclude that low carbon and high water contents alone do not explain the differences in the intercepts or slopes of the allometric relationships of jellyfish and other pelagic animals and that the evolutionary longevity of jellyfish and

  20. Achievements of New Generation Steel Project in China

    Institute of Scientific and Technical Information of China (English)

    Weng Yuqing

    2004-01-01

    Major achievements of the national project, Fundamental Research on New Generation of Iron and Steel Materials in China (NG Steel), are reviewed in the paper. Ultrafine grained steel technology, based on deformation induced ferrite transformation (DIFT)and successive microstructure changes, is illustrated for grain refinement in both plain low carbon steel and microalloyed steel. Delayed fracture resistance of alloy structure steel can be improved through prior austenite grain refinement. It is shown by results that nano scale precipitates play an important role to grain refinement in thin slab casting and rolling (TSCR)process. Progresses on super cleanliness, high homogeneity, welding and metallurgical process simulation are also briefly introduced.

  1. High speed railway promoting development of low-carbon economy in China%High speed railway promoting development of low-carbon economy in China

    Institute of Scientific and Technical Information of China (English)

    Zhou Xinjun

    2011-01-01

    Low-carbon Economy is a kind of economic developing mode which takes low energy consumption, low pollution and low discharge as its foundation. It is another important revolution of the human society after the agriculture civilization and industry civilization. It deals with various fields including low-carbon energy, low-carbon agriculture, lowcarbon industry, low-carbon transportation and low-carbon life, etc. Among those, low-carbon transportation is one of the important contents. Since high speed railway uses electricity as driving force, it runs without discharging waste gas, and it is a kind of clean and green transportation with little dust and smoke black. Therefore, the study of the relationship between the high speed railway and low-carbon economy is becoming one of the important frontier problems that confronting the theoretic circle. With demonstration analysis and comparative analysis, this paper discusses the comparative advantages of high speed railway in terms of energy saving and environment protection, treatment of sound pollution, land saving and reduction of external cost ( mainly pollution treatment cost), etc. compared with the other transportation modes and ordinary railway. Taking Beijing~Tianjin Intercity Railway as an example, the paper further demonstrates the distinctive advantages in respect of energy conservation and emission reduction. Besides, the paper also predicates the low-carbon effects after several high speed railways is put into operation in a few years. It is concluded that the development of high speed railways will meet the need of low-carbon economy and is significant for sustainable and steady development of economy and society.

  2. Effects of Deformation on Bainite Transformation During Continuous Cooling of Low Carbon Steels

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Hot deformation experiments were carried out on Gleeble 1500 thermo-mechanical simulator. The bainite transformation after deformation was investigated by optical microstructure analysis. The results indicated that the deformation accelerated the bainite transformation when the deformation was carried out at high temperature and no or little ferrite was precipitated before bainite transformation; when the deformation was carried out at low temperature, the deformation hindered the bainite transformation because a lot of ferrite precipitated before bainite transformation.

  3. Electrochemical evaluation for corrosion resistance of bacterial exopolysaccharides on low carbon steel

    Science.gov (United States)

    Corrosion is a global issue that affects safety and economics. There is an increasing demand for bio-based polymers for industrial applications and production of polymers by microorganisms is especially attractive. This work reports on the electrochemical and physical properties of 29 strains or fr...

  4. Microbiological corrosion in low carbon steels; Corrosion microbiologica en aceros de bajo carbono

    Energy Technology Data Exchange (ETDEWEB)

    Medina-Custodio, O; Ortiz-Prado, A; Jacobo-Armendariz, V. H; Schouwenaars-Franssens, R [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)]. E-mail: medina_1979@yahoo.com; armandoo@servidor.unam.mx; vjacobo@dgapa.unam.mx; raf_schouweenaars@yahoo.com

    2009-01-15

    The Microbiologically Induced Corrosion affects several industries, such as oil industry where it is estimated that 20% to 30% pipes failures are related with microorganism. The chemical reactions generate ions transfer, this validate the use of electrochemical technique for its analysis. Coupons submerged in a nutritional medium with presence and absence of three different microorganisms during two periods, 48 hours and 28 days were studied. Polarization resistance (Rp) and Electrochemical Impedance Spectroscopy (EIS) techniques were applied to determine the corrosively of the systems. The results show a greater corrosive effect of abiotic systems, this indicates a microorganisms protection effect to the metal, opposite to the first hypothesis. This result was ratified observing surface coupons by using Scanning Electron Microscopy (SEM) technique. A possible mechanism based on Evans - Tafel graph is proposed to explain inhibitor microorganism effect. [Spanish] La corrosion microbiologica es un tipo comun de deterioro que afecta diversas industrias, una de ellas es la petrolera en la que se estiman que el 20% o 30% de fallas en las tuberias de trasporte de hidrocarburos es favorecida por microorganismos. Las reacciones quimicas que sustentan estos, generan transferencia de iones, lo que justifica el empleo de tecnicas electroquimicas para su analisis. En este trabajo, se estudiaron probetas de acero de bajo carbono SAE 1018, sumergidas en un medio nutritivo rico en cloruros en presencia y ausencia de tres diferentes cargas microbianas, en tiempos de exposicion de 48 horas y 28 dias. Se realizaron ensayos de resistencia a la polarizacion (Rp) y espectroscopia de impedancia electroquimica (EIS) para determinar el efecto corrosivo de los diferentes sistemas. Los resultados muestran que el medio abiotico causa el mayor efecto corrosivo, lo que indica un efecto protector de los microorganismos al metal contradiciendo la hipotesis inicialmente propuesta. La observacion de las superficies en el microscopio electronico de barrido (MEB) apoya lo obtenido por las tecnicas electroquimicas. Para explicar la disminucion de la corrosividad del medio en presencia de microorganismos se propone un posible mecanismo de polarizacion catodica.

  5. Effect of Cathodic Protection on the Fatigue Crack Growth Behavior of Low Carbon Alloy Steels

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    1IntroductionCathodicprotectionisanusefulmethodtopreventsteelstructuresfromcorodinginmarineenvironment.Thismethodhasbeenwidel...

  6. Microstructure and strengthening parameters of ultra-thin hot strip of low carbon steel

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The microstructure and precipitation mechanism of ultra-thinhot strip produced by CSP technology were analyzed by electron back scattered diffraction (EBSD), H-800 transmission electron microscope (TEM) and thermodynamics theory. The EBSD results show that the finishing hot rolling microstructures are mixture of recrystallized and deformed austenite. After phase transformation, ferrite grains embody substructures and dislocations that led ultra-thin hot strip high strength and relatively low elongation rate. TEM observations show that there are a lot of fine and dispersive precipitates in microstructures. Most of aluminium nitrides are in grains, while coexisted precipitates of MnS along grain boundaries. Coexisted precipitates compose cation-vacancy type oxides such as Al2O3 in the core , while MnS at the fringe of surface. At the same time, reasons for microstructure refinement and strengthening effect were investigated.

  7. EFFECT OF STRAIN RATE ON MICROSTRUCTURE OF A LOW CARBON STEEL WIRE

    Directory of Open Access Journals (Sweden)

    H BOUHALAIS

    2011-12-01

    microstructure of the material in as received and deformed conditions. It is found that tensile properties depend on the wiredrawing area reduction (τw. The annealing temperatures and the grain size are determined; they also vary with τw .

  8. Analysis of Valence Electron Structure of RE in Solid Solution in Medium and Low Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    朱莹光; 刘艳; 刘志林; 刘伟东

    2004-01-01

    According to EET theory,the valence electron structures of RE in the solid solution of austenite,pearlite and martensite were calculated.The influence of RE in solid solution on phase transformation of pearlite and recrystallization of martensite was explained by the valence electron structure data of phases.Calculating results indicate that C element is favorite to enhance the number of RE in the solid solution.RE in the solute solution shortens the incubation period of proeutectoid ferrite,increases its quantity and carbon content,decreases the quantity of pearlite and thickness of its lamellas and lamellar spacing,then the strength and hardness of pearlite are improved and granular pearlite can be obtained.RE dissolved in martensite intensifies martensite,enhances tempering stability of martensite,increases its recrystallization temperature and prolongs the holding time needed during tempering.

  9. Bridging analytical approaches for low-carbon transitions

    Science.gov (United States)

    Geels, Frank W.; Berkhout, Frans; van Vuuren, Detlef P.

    2016-06-01

    Low-carbon transitions are long-term multi-faceted processes. Although integrated assessment models have many strengths for analysing such transitions, their mathematical representation requires a simplification of the causes, dynamics and scope of such societal transformations. We suggest that integrated assessment model-based analysis should be complemented with insights from socio-technical transition analysis and practice-based action research. We discuss the underlying assumptions, strengths and weaknesses of these three analytical approaches. We argue that full integration of these approaches is not feasible, because of foundational differences in philosophies of science and ontological assumptions. Instead, we suggest that bridging, based on sequential and interactive articulation of different approaches, may generate a more comprehensive and useful chain of assessments to support policy formation and action. We also show how these approaches address knowledge needs of different policymakers (international, national and local), relate to different dimensions of policy processes and speak to different policy-relevant criteria such as cost-effectiveness, socio-political feasibility, social acceptance and legitimacy, and flexibility. A more differentiated set of analytical approaches thus enables a more differentiated approach to climate policy making.

  10. Green growth: Policies for transition towards low carbon economies

    Energy Technology Data Exchange (ETDEWEB)

    Moe, Thorvald

    2012-11-01

    For the next fifty years and beyond, the world faces twin challenges: -Enhancing economic opportunities and living standards for a growing global population; -Addressing the environmental threats that, if left largely unaddressed, could undermine our abilities for longer term economic growth and development and the ability to reduce poverty. For twenty years the world community has attempted to face up to these challenges, notably global warming by a 'top down' international negotiation process under the auspices of the UN Framework Convention on Climate Change (UNFCCC). The paper discusses why this process has failed so far. To get out of this impasse, a 'bottom up' policy framework for green growth based on national preferences, possibilities and policies should be considered and is discussed in some detail. However, while green growth may enhance the transition towards low-carbon economies in the short and medium term, it is argued that a 'Global Green Deal' with regional and global rules of the game is needed to reduce the risk for unsustainable development in the longer term.(auth)

  11. Thermal Diffusivity of Traditional and Innovative Sheet Steels

    OpenAIRE

    2010-01-01

    The low carbon steels, used for the production of car bodies by deep drawing, are graduallu substituted by high strength steels for vehicle weight reduction. The drawn car body components are joined by welding and the welded points undergo a reduction of the local tensile strength. In developing an accurate welding process model, able to optimize process parameters and to predict the final local microstructure, a significant improvement can be given by the knowledge of the welded steels therm...

  12. Operation Mechanism of Farmers’ Professional Cooperatives from the Point of Low-Carbon Agricultural Products

    OpenAIRE

    2012-01-01

    We firstly take a look at internal logic of cluster development of low-carbon agricultural products. In combination with operation features of farmers’ professional cooperatives and actual requirements for cluster development of low-carbon agricultural products; we elaborate establishing benefit allocation mechanism, bearing education and training functions, forming low-carbon value, building low-carbon identification system, as well as realizing low-carbon value. According to these situati...

  13. Shift to a low carbon society through energy systems design

    Institute of Scientific and Technical Information of China (English)

    Toshihiko; NAKATA; Mikhail; RODIONOV; Diego; SILVA; Joni; JUPESTA

    2010-01-01

    Concern about global warming calls for an advanced approach for designing an energy system to reduce carbon emissions as well as to secure energy security for each country.Conventional energy systems tend to introduce different technologies with high conversion efficiency,leading to a higher average efficiency.Advanced energy systems can be achieved not by an aggregate form of conversion technologies but by an innovative system design itself.The concept of LCS(low carbon society) is a unique approach having multi-dimensional considerations such as social,economic and environmental dimensions.The LCS aims at an extensive restructuring of worldwide energy supply/demand network system by not only replacing the conventional parts with the new ones,but also integrating all the necessary components and designing absolutely different energy networks.As a core tool for the LCS design,energy-economic models are applied to show feasible solutions in future with alternatives such as renewable resources,combined heat and power,and smart grid operations.Models can introduce changes in energy markets,technology learning in capacity,and penetration of innovative technologies,leading to an optimum system configuration under priority settings.The paper describes recent trials of energy models application related to waste-to-energy,clean coal,transportation and rural development.Although the modelling approach is still under investigation,the output clearly shows possible options having variety of technologies and linkages between supply and demand sides.Design of the LCS means an energy systems design with the modelling approach,which gives solution for complex systems,choices among technologies,technology feasibility,R&D targets,and what we need to start.

  14. California's Low-Carbon Fuel Standard - Compliance Trends

    Science.gov (United States)

    Witcover, J.; Yeh, S.

    2013-12-01

    Policies to incentivize lower carbon transport fuels have become more prevalent even as they spark heated debate over their cost and feasibility. California's approach - performance-based regulation called the Low Carbon Fuel Standard (LCFS) - has proved no exception. The LCFS aims to achieve 10% reductions in state transport fuel carbon intensity (CI) by 2020, by setting declining annual CI targets, and rewarding fuels for incremental improvements in CI beyond the targets while penalizing those that fail to meet requirements. Even as debate continues over when new, lower carbon fuels will become widely available at commercial scale, California's transport energy mix is shifting in gradual but noticeable ways under the LCFS. We analyze the changes using available data on LCFS fuels from the California Air Resources Board and other secondary sources, beginning in 2011 (the first compliance year). We examine trends in program compliance (evaluated through carbon credits and deficits generated), and relative importance of various transport energy pathways (fuel types and feedstocks, and their CI ratings, including new pathways added since the program's start). We document a roughly 2% decline in CI for gasoline and diesel substitutes under the program, with compliance achieved through small shifts toward greater reliance on fuels with lower CI ratings within a relatively stable amount of transport energy derived from alternatives to fossil fuel gasoline and diesel. We also discuss price trends in the nascent LCFS credit market. The results are important to the broader policy debate about transportation sector response to market-based policies aimed at reducing the sector's greenhouse gas emissions.

  15. Advances in the research of nitrogen containing stainless steels

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The current status of nitrogen containing stainless steels at home and aboard has been introduced. The function and existing forms of nitrogen in the stainless steels, influence of nitrogen on mechanical properties and anti-corrosion properties as well as the application of nitrogen containing cast stainless steels were discussed in this paper. It is clear that nitrogen will be a potential and important alloying element in stainless steels. And Argon Oxygen Decarbonization (AOD) refining can provide an advanced manufacture process for nitrogen containing stainless steels with ultra-low- carbon and high cleanliness.

  16. Development of Low-carbon Forest Tourism with Emphasis on Construction of Urban Forest Park

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    This paper mainly points out that the urban forest tourism has so many advantages and it will hopefully become the support industry of low-carbon forestry, and the development of urban forestparks in low-carbon economy is extraordinarily important, especially when faced with some serious traditional problems. A series of proposals about revolutionary measures are put forwards.

  17. Fuzzy evaluation of low carbon development levels for logistic enterprises in China

    Directory of Open Access Journals (Sweden)

    Peixin Zhao

    2015-11-01

    Full Text Available Purpose: Under the background of global warming, low carbon economy, which is based on low waste and low pollution, has become a globally focused topic. Energy conservation, emission reduction and low carbon development have become irresistible trends of social development. A new set of low carbon evaluation index system for logistics enterprises is proposed. It is helpful for the better monitor of low carbon production and provide the optimization of industrial policies in China.Design/methodology/approach: Based on the problem that logistic analyses are facing under the background of low carbon economy, this paper firstly establishes a set of new evaluation indexes system, including 5 first-level indices and 28 second-level indices, for the low carbon development levels of logistics enterprises in China. To simplify the new evaluation system, the weight judgment method is then used to select indices, the validity judgment method and reliability coefficient judgment method are respectively used to test the validity and reliability of the evaluation systems. The simplified evaluation system consists of 4 first-class indices and 20 second-class indexes. Finally, numerical examples illustrate the validity and operability of the evaluation system.Findings: From the analysis and evaluation results, it is not difficult to obtain the rank of logistics enterprise according to the selected indexes or the overall evaluation indices. Low scores of some key indexes in strategy indices and technical indices cause low carbon emission performance. Moreover, The reason for the good low carbon performance of one enterprises is that it is in the lead on the key indexes of high weighs such as Perfection degree of low carbon development strategy, Level of transportation route optimization, etc. The new evaluation index system also helps enterprises to realize the sustainable development by identifying the key factors that affect the low carbon development level

  18. Plain carbon steel bipolar plates for PEMFC

    Institute of Scientific and Technical Information of China (English)

    WANG Jianli; SUN Juncai; TIAN Rujin; XU Jing

    2006-01-01

    Bipolar plates are a multifunctional component of PEMFC. Comparing with the machined graphite and stainless steels, the plain carbon steel is a very cheap commercial metal material. In this paper, the possibility of applying the plain carbon steels in the bipolar plate for PEMFC was exploited. In order to improve the corrosion resistance of the low carbon steel in the PEMFCs' environments,two surface modification processes was developed and then the electrochemical performances and interfacial contact resistance (ICR) of the surface modified plate of plain carbon steel were investigated. The results show that the surface modified steel plates have good corrosion resistance and relatively low contact resistance, and it may be a candidate material as bipolar plate of PEMFC.

  19. Industrial trial to produce a low clinker, low carbon cement

    Directory of Open Access Journals (Sweden)

    Vizcaíno-Andrés, L. M.

    2015-03-01

    Full Text Available A preliminary assessment of conditions for the industrial manufacture of a new cementitious system based on clinker-calcined clay and limestone, developed by the authors, referred as “low carbon cement” is presented. The new cement enables the substitution of more than 50% of the mass of clinker without compromising performance. The paper presents the follow-up of an industrial trial carried out in Cuba to produce 130 tonnes of the new cement at a cement plant. The new material proved to fulfill national standards in applications such as the manufacture of hollow concrete blocks and precast concrete. No major differences either in the rheological or mechanical properties were found when compared with Portland cement. Environmental assessment of the ternary cement was made, which included comparison with other blended cements produced industrially in Cuba. The new cement has proven to contribute to the reduction of above 30% of carbon emissions on cement manufacture.Se presenta la evaluación preliminar de las condiciones de fabricación industrial de un nuevo sistema cementicio a partir del empleo de clínquer; arcillas calcinadas y piedra caliza; desarrollado por los autores; denominado “cemento de bajo carbono”. El nuevo cemento posibilita la reducción de más de un 50% de la masa de clínquer; sin comprometer el comportamiento del material. El presente trabajo presenta el monitoreo de la producción industrial en una planta en Cuba; de 130 t del nuevo cemento. El cemento obtenido cumple con las regulaciones nacionales de calidad y su empleo tiene similar rendimiento que el cemento Pórtland para la producción de bloques y hormigón de 25 MPa. Se realiza el análisis de impacto ambiental del cemento ternario mediante la comparación con otros cementos producidos industrialmente. El nuevo cemento puede contribuir a la reducción de más del 30% de las emisiones de CO2 asociadas a la manufactura de cemento.

  20. Resistance microwelding of 316L stainless steel wire to block

    DEFF Research Database (Denmark)

    Friis, Kasper Storgaard; Khan, M.I.; Bay, Niels

    2011-01-01

    The excellent corrosion resistance of low carbon vacuum melted 316 stainless steel coupled with its non-magnetic properties makes it ideal for biomedical applications. The typical joint geometry for microcomponents, such as medical implants, includes joining of fine wire to a larger block. However......, this type of joint has received little attention in the current literature. The present study was conducted to examine the microstructure and mechanical properties of low carbon vacuum melted 316 stainless steel wire welded to a larger block. Results revealed solid state bonding occurring at low currents...

  1. 低碳经济视域下的我国低碳消费%China's low carbon consumption under the low-carbon economy

    Institute of Scientific and Technical Information of China (English)

    马照泽

    2013-01-01

      我国正处于城市化工业化发展的关键期,高消耗高污染的消费现状的改变,已经刻不容缓。城市低碳消费的关键是人们的消费理念、消费方式和消费行为三者之间的协调与配合。鉴于此,城市低碳消费的基本模式是:倡导低碳消费方式,树立低碳消费理念。控制碳排放和碳消耗,更重要的是改变人们的传统消费观念,让低碳消费的观念深入人心,从而让低碳消费成为社会主流认知。%China is in the critical period of city chemical industry development, the change of consumption situation of high consumption and high pollution, already brook no delay. The key of city low carbon consumption is the coordination and cooperation of people's consumption idea, consumption patterns and consumer behavior. In view of this, the basic pattern of the city low carbon consumption is: advocate low carbon consumption, establish the concept of low carbon consumption. Controlling carbon emissions and carbon consumption, more important is to change the traditional consumption concept of people, let the low carbon consumption ideas win support among the people, so that the low carbon consumption has become the mainstream of social cognition.

  2. Research on the Influencing Factors of Rural Low-carbon Economic Development and Government Regulation

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    This paper analyses the main factors causing sluggish development of rural low-carbon economy in China as follows:the rural energy structure is irrational;the infrastructure and technology are relatively backward;system of laws,regulations and policy is not sound;fund-raising mechanism develops slowly;farmers’ low-carbon awareness and ability are limited.On the basis of these unfavorable factors,from the perspective of government regulation,feasible strategies are put forward in line with the actual situation of rural low-carbon economic development in China.

  3. The nanostructure and microstructure of steels: Electrochemical Tafel behaviour and atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Valeria A. [Departamento de Farmacia-Bioquimica, Faculdades Federais Integradas de Diamantina, FAFEID, Rua da Gloria, 187 Centro 39100-000 Diamantina, Minas Gerais (Brazil); Paquim, Ana M. Chiorcea [Departamento de Quimica, Universidade de Coimbra, 3004-535 Coimbra (Portugal); Cavaleiro, Albano [Departamento de Engenharia Mecanica, Universidade de Coimbra, 3030 Coimbra (Portugal); Brett, Christopher M.A. [Departamento de Quimica, Universidade de Coimbra, 3004-535 Coimbra (Portugal)]. E-mail: brett@ci.uc.pt

    2005-12-15

    The influence of chemical composition and heat treatment on a low-carbon steel, chromium steel and high speed steel has been examined by polarisation curves and electrochemical parameters deduced from the Tafel plots. The electrochemical corrosion resistance, which is small between the as-received steels become greater after heat treatment, following the order: carbon steel < chromium steel {approx} high speed steel. To explain these differences, the nano- and microstructure of the steels has been characterized by the ex situ techniques of atomic force microscopy and optical microscopy, before and after surface etching with Nital (a solution of 5% HNO{sub 3} in ethanol). This causes preferential attack of the ferrite phases showing the carbide phases more clearly. From these nanostructural studies it was possible to better understand why the passive films formed on chromium steel and high speed steel have superior protective properties to those formed on carbon steel.

  4. Low-Carbon Based Multi-Objective Bi-Level Power Dispatching under Uncertainty

    OpenAIRE

    2016-01-01

    This research examines a low-carbon power dispatch problem under uncertainty. A hybrid uncertain multi-objective bi-level model with one leader and multiple followers is established to support the decision making of power dispatch and generation. The upper level decision maker is the regional power grid corporation which allocates power quotas to each follower based on the objectives of reasonable returns, a small power surplus and low carbon emissions. The lower level decision makers are the...

  5. Low-carbon building assessment and multi-scale input-output analysis

    Science.gov (United States)

    Chen, G. Q.; Chen, H.; Chen, Z. M.; Zhang, Bo; Shao, L.; Guo, S.; Zhou, S. Y.; Jiang, M. M.

    2011-01-01

    Presented as a low-carbon building evaluation framework in this paper are detailed carbon emission account procedures for the life cycle of buildings in terms of nine stages as building construction, fitment, outdoor facility construction, transportation, operation, waste treatment, property management, demolition, and disposal for buildings, supported by integrated carbon intensity databases based on multi-scale input-output analysis, essential for low-carbon planning, procurement and supply chain design, and logistics management.

  6. Optimal Strategies for Low Carbon Supply Chain with Strategic Customer Behavior and Green Technology Investment

    Directory of Open Access Journals (Sweden)

    Wen Jiang

    2016-01-01

    Full Text Available Climate change is mainly caused by excessive emissions of carbon dioxide and other greenhouse gases. In order to reduce carbon emissions, cap and trade policy is implemented by governments in many countries, which has significant impacts on the decisions of companies at all levels of the low carbon supply chain. This paper investigates the decision-making and coordination of a low carbon supply chain consisting of a low carbon manufacturer who produces one product and is allowed to invest in green technology to reduce carbon emissions in production and a retailer who faces stochastic demands formed by homogeneous strategic customers. We investigate the optimal production, pricing, carbon trading, and green technology investment strategies of the low carbon supply chain in centralized (including Rational Expected Equilibrium scenario and quantity commitment scenario and decentralized settings. It is demonstrated that quantity commitment strategy can improve the profit of the low carbon supply chain with strategic customer behavior. We also show that the performance of decentralized supply chain is lower than that of quantity commitment scenario. We prove that the low carbon supply chain cannot be coordinated by revenue sharing contract but by revenue sharing-cost sharing contract.

  7. Microstructures and Mechanical Properties of Fe-Mn-(Al, Si) TRIP/TWIP Steels

    Institute of Scientific and Technical Information of China (English)

    DING Hua; TANG Zheng-You; LI Wei; WANG Mei; SONG Dan

    2006-01-01

    The mechanical properties and microstructure of two low carbon high manganese steels with 23.8% (No.1) and 33% (No.2) (mass percent) of manganese were investigated. The results showed that No.1 steel possesses high strength and high plasticity, and No.2 steel has a relatively high strength and extraordinary plasticity. The No.1 steel exhibits both TRIP (transformation induced plasticity) and TWIP (twin induced plasticity) effects during the deformation; while only TWIP effect appeared under the same deformation condition for No.2 steel. The comparison between the microstructures and mechanical properties of two steels was made, and the strengthening mechanisms were also analyzed.

  8. Three-Sheet Spot Welding of Advanced High-Strength Steels

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Friis, Kasper Storgaard; Zhang, W.

    2011-01-01

    The automotive industry has introduced the three-layer weld configuration, which represents new challenges compared to normal two-sheet lap welds. The process is further complicated by introducing high-strength steels in the joint. The present article investigates the weldability of thin, low....... The weld mechanisms are analyzed numerically and compared with metallographic analyses showing how the primary bonding mechanism between the thin, low-carbon steel sheet and the thicker sheet of high-strength steel is solid-state bonding, whereas the two high-strength steels are joined by melting, forming...... a weld nugget at their mutual interface. Despite the absence of the typical fusion nugget through the interface between the low-carbon steel and high-strength steel, the weld strengths obtained are acceptable. The failure mechanism in destructive testing is ductile fracture with plug failure....

  9. Benefits of Low Carbon Development Strategies in Emerging Cities of Developing Country: a Case of Kathmandu

    Directory of Open Access Journals (Sweden)

    Shree Raj Shakya

    2016-06-01

    Full Text Available Kathmandu is one of the fastest growing cities in South Asia facing various challenges related to climate change, local pollutants emissions and energy security of supply. This study analysed the greenhouse gas mitigation potential in different economic sectors of the city by using Long-range Energy Planning (LEAP frame work. It shows that the effect of implementing various low carbon development strategy options can reduce 35.2% of total greenhouse gas emission from energy use as compared to the base case scenario in 2030. This indicates the need for exploring the possibility of utilizing the global climate funds and adopting voluntary mechanisms for greenhouse gas mitigation. The estimated demand side technology investment cost of low carbon measures for different sectors ranges from less than US$ 1/tonne CO2e for residential sector to US$ 99/tonne CO2e for transport sector. The low carbon options also results co-benefits in terms of significant reduction in emission of local pollutants and improvement of energy security. As Government of Nepal has envisioned following low carbon economic development path on the long run, there is the need of establishment of regulatory framework, institutional framework and development of clear action plans for realizing the implementation of low carbon development strategy measures in the country.

  10. Global Trend of Low-carbon Economy and China's Responses

    Institute of Scientific and Technical Information of China (English)

    He Jiankun; Zhou Jian; Liu Bin; Sun Zhenqing

    2011-01-01

    Based on the analysis on the global economic crisis,climate change crisis and their mutual underlying reasons,the authors believe that low-carbon economy has become an inevitable choice to break through the dual crises,coordinate the economic development,and protect the global climate.The global trend of low-carbon economy finds expression in Green Recovery currently,while,in a long run,it will give rise to a new pattern of world competition in politics,economy,technology,trade and finance.The impact of the global trend of low-carbon economy on China can not be overlooked,and it is both a challenge and an opportunity for China's future development.Based on comparative studies on the low-carbon economy of China,the U.S.,EU and Japan,the authors conclude that China should blaze a new path of lowcarbon economy development with Chinese characteristics,and the authors have put forward relevant countermeasures for China to address the global trend of low-carbon economy from angles of countries,enterprises and the public

  11. The Research on Low Carbon Logistics Routing Optimization Based on DNA-Ant Colony Algorithm

    Directory of Open Access Journals (Sweden)

    Liyi Zhang

    2014-01-01

    Full Text Available As the energy conservation and emission reduction and sustainable development have become the hot topics in the world, low carbon issues catch more and more attention. Logistics, which is one of the important economic activities, plays a crucial role in the low carbon development. Logistics leads to some significant issues about consuming energy and carbon emissions. Therefore, reducing energy consumption and carbon emissions has become the inevitable trend for logistics industry. Low carbon logistics is introduced in these situations. In this paper, from the microcosmic aspects, we will bring the low carbon idea in the path optimization issues and change the amount of carbon emissions into carbon emissions cost to establish the path optimization model based on the optimization objectives of the lowest cost of carbon emissions. According to different levels of air pollution, we will establish the double objectives path optimization model with the consideration of carbon emissions cost and economy cost. Use DNA-ant colony algorithm to optimize and simulate the model. The simulation indicates that DNA-ant colony algorithm could find a more reasonable solution for low carbon logistics path optimization problems.

  12. Stress-Corrosion Cracking of Metallic Materials. Part III. Hydrogen Entry and Embrittlement in Steel

    Science.gov (United States)

    1975-04-01

    Strength Steels," Stress Corrosion Cracking in High-Strength Steels and in Titanium and Altuninum Alloys, Naval Rasearch Laboratory, Washington, D.C...to pickling solutions. In all of these examples, the sulfide, cyanide, etc., caused a hydrogen-related problem that would not have existed in their...desorption reaction. In studying the pickling of low-carbon steel in various strong acids, Hudson’ 4 measured the corrosion rate and amount of hydr-ogen

  13. Low carbon Finland 2050. VTT clean energy technology strategies for society

    Energy Technology Data Exchange (ETDEWEB)

    Koljonen, T.; Simila, L.; Sipila, K. [and others

    2012-11-15

    The Low Carbon Finland 2050 project by VTT Technical Research Centre of Finland aims to assess the technological opportunities and challenges involved in reducing Finland's greenhouse gas emissions. A target for reduction is set as at least 80% from the 1990 level by 2050 as part of an international effort, which requires strong RD and D in clean energy technologies. Key findings of the project are presented in this publication, which aims to stimulate enlightening and multidisciplinary discussions on low-carbon futures for Finland. The project gathered together VTT's technology experts in clean energy production, smart energy infrastructures, transport, buildings, and industrial systems as well as experts in energy system modelling and foresight. VTT's leading edge 'Low Carbon and Smart Energy' enables new solutions with a demonstration that is the first of its kind in Finland, and the introduction of new energy technology onto national and global markets. (orig.)

  14. The Impact of Transport Mode and Carbon Policy on Low-Carbon Retailer

    Directory of Open Access Journals (Sweden)

    Yi Zheng

    2015-01-01

    Full Text Available Low-carbon retail has become a strategic target for many developed and developing economies. This study discusses the impact of transport mode and carbon policy on achieving this objective. We investigated the retailer transportation mode, pricing, and ordering strategy, which all consider carbon-sensitive demand under the carbon cap-and-trade policy. We analyzed the optimal decision of retailer and their maximum profit affected by transport mode and cap-and-trade policy parameters. Results show that the two elements (cap-and-trade policy and consumer low-carbon awareness could encourage the retailer to choose low-carbon transportation. The two elements also influence the profit and optimal decision of retailer. Finally, a numerical example is presented to illustrate the applicability of the model.

  15. Process Reengineering of Cold Chain Logistics of Agricultural Products Based on Low-carbon Economy

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Through the process analysis of cold chain logistics of agricultural products,we find that cold chain logistics of agricultural products contradict the development model of low-carbon economy to some extent.We apply the development idea of low-carbon economy,introduce the thirdparty logistics companies,establish distribution center of cold chain logistics of agricultural products,and strengthen information sharing,to reengineer the process of cold chain logistics of agricultural products in China.The results show that applying low-carbon economy to process reengineering of cold chain logistics of agricultural products,has advantages of increasing added value of products,promoting scale merit and abating lag,plays a role in promoting emission reduction,high efficiency and environmental protection in the process of cold chain logistics of agricultural products in China.

  16. Simulation and Optimization of One Live Pig Low-Carbon Industry Chain Using SD-RCCM

    Directory of Open Access Journals (Sweden)

    Jiuping Xu

    2013-01-01

    Full Text Available The destruction of the natural environment has been drawing more and more attention. Developing low-carbon industry chains is an effective solution to the conflict between rapid economic growth and high CO2 emissions. Summarizing various traditional and new industry chain sustainable development, live pig industry was chosen as a typical industry chain to study low-carbon development using a system dynamics and random chance-constrained model (SD-RCCM. Leshan, a world natural and cultural heritage area in China, was selected as a typical city to analyze the low-carbon pig industry. Three different programs based on distribution ratios were selected to study this industry. The results showed that program 1, which considers both environmental and economic benefits, realizes sustainable development. In order to extend the pig industry chain and fully utilize pig ordure and other waste, introducing a Clean Development Mechanism (CDM and household biogas exploitation program is recommended.

  17. China's Development of Low-Carbon Eco-Cities and Associated Indicator Systems

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Nan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); He, Gang [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Williams, Christopher [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-07-01

    China's urban population surpassed its rural population historically in 2011, when the number of Chinese living in towns and cities reached about 690 million1. In the years to come, cities in China will face major challenges as their rapidly increasing populations burden already crowded infrastructure systems and exacerbate environmental and climate change issues, threatening public health and quality of life. Low-carbon cities may be key to addressing those challenges, especially as regards mitigating and adapting to climate change. Government entities at both the central and local level have moved aggressively on building low-carbon eco-cities. According to statistics reported by the Chinese Society for Urban Studies, by February of 2011, China will have 230 cities at the prefecture-and-above level that have proposed to establish themselves as “eco-cities,” accounting for 80.1% of the 287 such cities nationally. Of those 230 cities, 133, or 46.3%, have established targets to develop specifically as “lowcarbon cities” (Chinese Society for Urban Studies 2011). Given the proposed scale of the effort, China’s potential success or failure in demonstrating and implementing low-carbon eco-cities could greatly affect how the world addresses both the climate change impacts of urbanization and the sustainable development of cities. Despite the multiple guidelines that have been developed, it remains unclear what defines a low-carbon eco-city. Additionally, although more than 100 indicators have been used or proposed for assessing such cities, few relate directly to energy use or carbon emissions. Nonetheless, policy makers and leaders continue to demand comprehensive toolboxes to facilitate development of low-carbon eco-cities. This paper presents the results of an extensive literature review of the development of low-carbon eco-cities in China. The paper also qualitatively and quantitatively analyzes 11 major indicator systems that researchers, planners

  18. Establishment of CSR Matter-Element Evaluation Model in Perspective of Low Carbon Economy in China

    Directory of Open Access Journals (Sweden)

    Li Furong

    2013-06-01

    Full Text Available With the development of CSR concept, more and more enterprises begin to bring CSR into practice. Especially in the era of low-carbon economy develops quickly, CSR practice is going to mature. In order to make a scientific evaluation on CSR and promote the comprehensive development of CSR, this study develop a new CSR evaluation model under requires of low-carbon economy development. This CSR evaluation model combined G1 weighting method with the Matter-Element Model and finally verified by an example. What we do in this study will provide a good guidance for the development of CSR evaluation and practices.

  19. Low Carbon Concept:Functional & Green Casual Fabrics Are Enjoying A Favor

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Starting from the low-carbon concept to practice in the specific production requires recollected thinking and judgments. It can be seen that "functional" and "green" casual fabrics are becoming more and more important evidently. From the trend to start businesses, enterprises could find an "ultimate goal" for low carbon in such production processes as matching the raw materials, printing processes, finishing and others, and then plus the careful planning of cost, the environmentally friendly and cost-effective products enable the enterprises to seize the market opportunities.

  20. Techno-economic and environmental analysis of low carbon energy technologies: Indian perspective

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Vijay Prakash; Kumar, Rahul; Kumar, Manish; Deswal, Surinder; Chandna, Pankaj

    2010-09-15

    In this paper, techno-economic and an environmental investigation and analysis of Low Carbon Technologies (LCTs) has been presented, with special emphasis on India. The paper identify, analyze and recommend, on the basis of available and collected / collated information and data, the promising and potential low carbon energy technology options suited to Indian conditions for grid connected power generation. The evaluation criteria adopted include - emission reduction potential, technological feasibility, and economic viability; and on its basis recommend a detailed action plan and strategy for guiding future research and development with a more focused approach considering current Indian policy framework.

  1. Opportunities for A Low Carbon Future——China's Clean Revolution Ⅱ

    Institute of Scientific and Technical Information of China (English)

    Audrey GUO

    2009-01-01

    @@ Despite economic downturn,China's domestic markets continue to scale up low carbon technology.A new report that was released in Beijing in August by the Climate Group shows that in an incredibly short time China has taken the lcad in the race to develop and commercialize a range of low carbon technologies.On the back of ambitious government policies and a new breed of entrepreneurs,Chinese businesses are amongst the top producers of electric vehicles,wind turbines,solar panels and energy efficient appliances.

  2. 低碳生活居住环境设计%Low-carbon Living Environment Design

    Institute of Scientific and Technical Information of China (English)

    韦宇航

    2012-01-01

    Based on the review of the influence of human activity on global environment, and recognition of current climate warming, it is considered that human activity is the primary reason and climate change has caused serious global environmental problems and threatened human ' s survival and development. After the introduction of low carbon and conclusion of the main content and development of researches, it has emphasized that low-carbon urban living mode is an important component of low-carbon urban planning. In view of the situation of China, the main content of low-carbon urban living mode has been illustrated from the perspective of low-carbon life behavior, low-carbon life consumption and carbon budget life mode. On this basis, the purpose and significance of low-carbon living environment design, design principles and requirements, and low-carbon life measures have been analyzed.%回顾了人类活动对地球环境的影响,基于对当前气候变暖的认识,认为人类活动是其主要原因,气候变化导致了严重的地球环境问题,危害着人类的生存发展.介绍了低碳城市的主要含义,并综述了相关研究的主要内容与研究进展,强调低碳城市生活模式是低碳城市规划的重要组成部分,并针对我国具体情况,从低碳生活行为、低碳生活消费、碳预算生活方式3个方面指明了我国低碳城市生活模式研究的主要内容.在此基础上,分析了低碳生活居住环境设计的目的和意义,设计的基本原则和要求,以及低碳生活的措施.

  3. Planning and Construction of Low Carbon Cities:The Relevance of Cost-Benefit Analysis

    Institute of Scientific and Technical Information of China (English)

    Stanley; C.T.YIP

    2011-01-01

    Cities are the major source of carbon dioxide emissions in China,and are the critical locations where emissions should be effectively managed.Adopting a low carbon urban development model is the pathway towards reducing the emissions.A low carbon city development model means achieving efficient and effective urban growth through low energy consumption and low emissions.While many local authorities in China have started to express the intention to construct low carbon cities,it is important to emphasize the need to apply a Cost-Benefit Analysis (CBA) to low carbon urban policies and development projects.Since all policies and projects will have their costs and benefits to the society,the effects of the policies and projects on reducing emissions should be measured and assessed objectively.Through the setting up of an analysis framework to assess the costs and benefits,one can provide a scientific basis for decision making,and enhance the overall efficiency in the use of resources for the society as a whole.

  4. A Guidebook for Low-Carbon Development at the Local Level

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Nan; Price, Lynn; Ohshita, Stephanie; Zheng, Nina; Min, Hu

    2011-10-31

    This report aims to provide a manual with a menu of the successful policies and measures for local governments in China to create low carbon plan or climate action plans. This manual includes a comprehensive list of successful policies and best practices.

  5. Local transition strategies for low carbon construction and housing – studies of innovative Danish municipalities

    DEFF Research Database (Denmark)

    Holm, Jesper; Søndergård, Bent; Stauning, Inger

    The paper sets out to discuss and characterize the innovative local practices among Danish municipalities, when it comes to clean-tech related CO2 reductions from the housing sector. This paper is part of our general aim to identify and develop planning concepts of transition for low carbon...... construction and housing....

  6. Renewable and low-carbon energies as mitigation options of climate change for China

    NARCIS (Netherlands)

    Urban, F.; Benders, R. M. J.; Moll, H. C.

    2009-01-01

    This article discusses how renewable and low-carbon energies can serve as mitigation options of climate change in China's power sector. Our study is based on scenarios developed in PowerPlan, a bottom-up model simulating a countries' power sector and its emissions. We first adjusted the model to Chi

  7. Development of Affordable, Low-Carbon Hydrogen Supplies at an Industrial Scale

    Science.gov (United States)

    Roddy, Dermot J.

    2008-01-01

    An existing industrial hydrogen generation and distribution infrastructure is described, and a number of large-scale investment projects are outlined. All of these projects have the potential to generate significant volumes of low-cost, low-carbon hydrogen. The technologies concerned range from gasification of coal with carbon capture and storage…

  8. Research on Development Measures of Low-carbon Transportation in Beijing

    Directory of Open Access Journals (Sweden)

    Gang Zong

    2014-05-01

    Full Text Available With the development of economy, vehicle ownership is growing rapidly. People gradually concentrate on the energy consumption of transportation industry and environmental pollution. Because of air pollution, energy consumption, climate change and other problems, people in major cities pay more attention to energy conservation and emission reduction in transportation. Transportation industry is an important source of energy consumption and carbon emission. Facing the task of energy conservation and emission reduction in the Twelfth Five-year Plan for economic and social development, it is extremely urgent to adjust the transportation industry and take road of low-carbon transportation. Low-carbon transportation is an important breakthrough for Beijing to readjust industrial structure and transform the economic development pattern; it is also a demand for Culture-enriched Beijing, Technology-empowered Beijing, Environment-friendly Beijing as well as an inevitable choice for the coordinated development of economy, society and environment. This paper analyzes the status quo and major problems facing Beijing low-carbon transportation and comes up with policy advice for low-carbon transportation development.

  9. Developing and Using Green Skills for the Transition to a Low Carbon Economy

    Science.gov (United States)

    Brown, Mike

    2015-01-01

    One of the strategies being advocated in response to climate change is the need to transition to a low carbon economy. Current projections show that within this transition, new jobs will be created, some eliminated and most others subjected to change. This article reports findings from interviews with a selection of twenty participants who are…

  10. Study on the serialization and applications of low carbon ductile iron

    Institute of Scientific and Technical Information of China (English)

    SHU Xin-fu; SHU Rui; CHANG Dian-cun; ZHANG Xiao-long; ZHU Yan-dong; LI Ling-fang; LI Yu-zhong

    2005-01-01

    Both the production process and the chemical composition of Sx were studied, and the serialization of iow carbon ductile iron was also discussed. It was indicated that Sx modifier was sensitive to the carbon equivalent (CE) of molten iron and to some alloying elements too. When the CE of molten iron and the contents of alloying elements were changed, the content of Sx must be revised with the change correspondingly. Low carbon ductile iron can be stably changed into the one that non-carbon acicular ferrite and retained austenite (about 25%-28%) by quasi-casting bainitic process of using Sx-2 modifier treated Si-Mn-Cr-Cu-alloyed low carbon molten iron. The austenitic low carbon as-cast ductile iron could be obtained by the Ni-Si-Cr 35 5 2 percent alloys molten iron with less than 2% carbon treated by type Sx-3 modifier. The high-toughness ferritic low carbon as-cast ductile iron which contained more than 85 % ferrite in matrix could be got after the molten iron treated by type Sx-4 modifier, and it's elongation was more than 10 %.

  11. The MDGs and Beyond : Can Low Carbon Development be Pro-poor?

    NARCIS (Netherlands)

    Urban, Frauke

    2010-01-01

    Climate change adaptation and mitigation needs to cut across all poverty reduction efforts, including any post-2015 architecture. However, low carbon development (LCD) debates to date have been mainly about high- and middle-income countries. There are good reasons why even the poorest countries with

  12. Low carbon rural housing provision in China: Participation and decision making

    NARCIS (Netherlands)

    Liu, Wenling; Spaargaren, G.; Mol, A.P.J.; Heerink, N.B.M.; Wang, C.

    2014-01-01

    Under the national strategy of ‘building a new socialist countryside’, concentrated rural housing is increasing in some rural regions in China. In this research we use three case studies to analyze decision making on concentrated rural housing and the potential for future low carbon rural housing. T

  13. Informed public choices for low-carbon electricity portfolios using a computer decision tool.

    Science.gov (United States)

    Mayer, Lauren A Fleishman; Bruine de Bruin, Wändi; Morgan, M Granger

    2014-04-01

    Reducing CO2 emissions from the electricity sector will likely require policies that encourage the widespread deployment of a diverse mix of low-carbon electricity generation technologies. Public discourse informs such policies. To make informed decisions and to productively engage in public discourse, citizens need to understand the trade-offs between electricity technologies proposed for widespread deployment. Building on previous paper-and-pencil studies, we developed a computer tool that aimed to help nonexperts make informed decisions about the challenges faced in achieving a low-carbon energy future. We report on an initial usability study of this interactive computer tool. After providing participants with comparative and balanced information about 10 electricity technologies, we asked them to design a low-carbon electricity portfolio. Participants used the interactive computer tool, which constrained portfolio designs to be realistic and yield low CO2 emissions. As they changed their portfolios, the tool updated information about projected CO2 emissions, electricity costs, and specific environmental impacts. As in the previous paper-and-pencil studies, most participants designed diverse portfolios that included energy efficiency, nuclear, coal with carbon capture and sequestration, natural gas, and wind. Our results suggest that participants understood the tool and used it consistently. The tool may be downloaded from http://cedmcenter.org/tools-for-cedm/informing-the-public-about-low-carbon-technologies/ .

  14. Energy and low carbon development efforts in Ghana: institutional arrangements, initiatives, challenges and the way forward

    Directory of Open Access Journals (Sweden)

    Emmanuel Kofi Ackom

    2016-04-01

    Full Text Available Over the years, Ghana has invested considerable effort and resources together with international partners to develop the energy sector and to mainstream energy low carbon pathways into national development plans. Low carbon development (LCD provides a good opportunity, of not only building upon earlier energy and climate change local processes and structures but also help to mainstream low carbon agenda in economic activities and national development plans. For this to work however, require efficient institutions and effective institutional arrangements. Based on extensive literature analysis, personal communications and inputs from stakeholders, the paper highlights the key institutional arrangements, their interactions, challenges and proffers recommendations for improvements. To improve energy and low carbon development effort from the perspectives of institutional structures, would require, clearer institutional mandates, continuous improvements in institutional coordination (intra and inter, capacity and skills development, sustained visibility of the essence of energy and LCD at high political levels as well as engagement by civil societies. Equally important are the issues of finance, data availability and quality, monitoring and evaluation.

  15. Exploring a low carbon development in rural China : the role of households

    NARCIS (Netherlands)

    Liu Wenling, Wenling

    2013-01-01

    As the largest emitter of greenhouse gasses in the world, China is facing great pressure to reduce these emissions in order to mitigate global climate change. Developing a low carbon economy has been initiated in many countries, including China, as a means to tackle this issue. China’s actions

  16. Effect of Cr, Mo and W on the Microstructure of Al Hot Dipped Carbon Steels

    Energy Technology Data Exchange (ETDEWEB)

    Trung, Trinh Van [School of Materials Science and Engineering, Hanoi University of Science and Technology, Hanoi (Viet Nam); Kim, Min Jung; Park, Soon Yong; Vadav, Poonam; Abro, Muhammad Ali; Lee, Dong Bok [School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon (Korea, Republic of)

    2014-02-15

    A low carbon steel, Fe-2.25%Cr steel (ASTM T22), and Fe-2.25%Cr-1.6%W steel (ASTM T23) were aluminized by hot dipping into molten Al baths. After hot-dipping, a thin Al-rich topcoat and a thick alloy layer formed on the surface. The topcoat consisted primarily of a thin Al layer that contained a small amount of Fe, whereas the alloy layer consisted of Al-Fe intermetallics such as Al{sub 5}Fe{sub 2} and AlFe. Cr, Mo, and W in T22 and T23 steels reduced the thickness of the topcoat and the alloy layer, and flattened the reaction front of the aluminized layer, when compared to the low carbon steel.

  17. Research of Low-Carbon Consumption Mode on the Basis of Low-Carbon Economy%基于低碳经济的消费模式探析

    Institute of Scientific and Technical Information of China (English)

    常媛媛

    2011-01-01

    In the background of global climate changes,Low-carbon economy has become the social consensus.Low-carbon economy is essentially a kind of consumption mode,and the Low-carbon consumption is an important part of the development of Low-carbon economy.We should build low carbon consumption environment,conception of low-carbon consumption and other ways to promote the establishment of low-carbon consumption patterns through the increasing research and development on the low-carbon technologies.%在全球气候变化的大背景下,发展低碳经济已成为全社会的共识。低碳经济本质上是一种消费模式,而低碳消费是低碳经济发展的重要环节。应通过加大低碳技术研发,建立低碳消费环境,引导低碳消费理念等途径推进低碳消费模式的建立。

  18. Low-Carbon City Policy Databook: 72 Policy Recommendations for Chinese Cities from the Benchmarking and Energy Savings Tool for Low Carbon Cities

    Energy Technology Data Exchange (ETDEWEB)

    Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; Zhou, Nan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; Fridley, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; Ohshita, Stephanie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; Khanna, Nina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; Hong, Lixuan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; He, Gang [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; Romankiewicz, John [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area. Energy Analysis and Environmental Impacts Division. China Energy Group; Min, Hu [Energy Foundation China, Beijing (China)

    2016-07-01

    This report is designed to help city authorities evaluate and prioritize more than 70 different policy strategies that can reduce their city’s energy use and carbon-based greenhouse gas emissions of carbon dioxide (CO2) and methane (CH4). Local government officials, researchers, and planners can utilize the report to identify policies most relevant to local circumstances and to develop a low carbon city action plan that can be implemented in phases, over a multi-year timeframe. The policies cover nine city sectors: industry, public and commercial buildings, residential buildings, transportation, power and heat, street lighting, water & wastewater, solid waste, and urban green space. See Table 1 for a listing of the policies. Recognizing the prominence of urban industry in the energy and carbon inventories of Chinese cities, this report includes low carbon city policies for the industrial sector. The policies gathered here have proven effective in multiple locations around the world and have the potential to achieve future energy and carbon savings in Chinese cities.

  19. Tool steels

    DEFF Research Database (Denmark)

    Højerslev, C.

    2001-01-01

    resistance against abrasive wear and secondary carbides (if any) increase the resistance against plastic deformation. Tool steels are alloyed with carbide forming elements (Typically: vanadium, tungsten, molybdenumand chromium) furthermore some steel types contains cobalt. Addition of alloying elements...

  20. Capturing low-carbon power system dynamics : Interactions between intermittent renewables and power plants with CO2 capture and storage

    NARCIS (Netherlands)

    Brouwer, A.S.

    2015-01-01

    Low-carbon power systems are needed by the year 2050 to meet climate change mitigation targets. This dissertation investigates the operational and economic feasibility of such future low-carbon power systems by simulating the Dutch and European power systems. Particular attention is paid to the impa

  1. Visualizing the application of GIS in transformation towards a sustainable development and a low carbon society

    Science.gov (United States)

    Ahmad, M. H.; Ariffin, A.; Malik, T. A.

    2014-02-01

    A strategy for sustainable development is a significant milestone on the road to a more socially, economically and environmentally responsible society. It creates a framework within which the stakeholders can make a strong contribution to a better future. Because of the merits and growing interest in sustainable development, the race is on for researchers and stakeholders in the construction sector to initiate actions to reduce the negative impacts of development and sharpen their competitive edge. The cities should be created with a vision which supports harmonious communities and living conditions through sustainable urban development. The resources must be used efficiently while reducing the development impact on human health and environment during the buildings' life cycle. Environmental auditing and pressure-state response based models to monitor sustainable development in Malaysia should be developed. A data availability and sharing system should be developed and implemented to facilitate for the use in the establishment of sustainable development and low carbon society. Ideas which affect millions of people and guide the policies of nations must be accessible to all. Only thus can they permeate the institutions from the local to the global level. Creating sustainable development and low carbon societies depends on the knowledge and involvement of all stakeholders in the industry. So what is our level of understanding of GIS and its application? The development of geospatial data in Malaysia is important because the successful implementation of sustainable development and low carbon projects depend largely on the availability of geospatial information. It would facilitate the stakeholders and resolve some of the problems regarding the availability, quality, organisation, accessibility and sharing of spatial information. The introduction of GIS may change the way for better sustainable urban development and low carbon society performance. The use of GIS is to

  2. Steel Spring

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Tarnished Hebei Iron and Steel Group regains chance to shine A lthough it is too early to tell whether the steel-making sector has emerged [from its gloom, a big divide is openling between China’s large and small producers. While most of the marginal players are still reeling from a market contagion, steel titans like the Shanghai-based Baosteel

  3. Low Carbon Development: Challenges for China as a Rapidly Industrializing Developing Country

    Institute of Scientific and Technical Information of China (English)

    HongboChen; HuaiguoHu; JiahuaPan

    2005-01-01

    China is in a stage of rapid industrialization. Over the past two decades, the size of the Chinese economy has more than quadrupled and energy consumption has more than doubled. The drive for more industrialization over the next two decades is leading to similar dynamics on a much larger scale. The net increase in emissions of CO2 between 1990 and 2001 amounted to 823 million tons, accounting for 27percent of the world total. Energy supplies and security are key constraints to industrialization; therefore, mitigation of emissions can in fact contribute to the achievement of development goals. There is a need for China to pursue a path of low carbon development. However, low and zero carbon technologies can hardly meet the demands for the physical expansion of the economy. In order to cope with the challenges for low carbon development, factors such as responsibility, capability, and potentials have to be taken into account in an international climate regime.

  4. Research of System Building Basing on the Low Carbon Economy About Carbon Accounting for the Enterprise

    Directory of Open Access Journals (Sweden)

    Yao Liqiong

    2016-01-01

    Full Text Available As global warming has become truth, is developing as a new economic model, The new economic development model has given rise to an important branch of environmental accounting, namely carbon accounting. At first, this paper discusses the carbon accounting theoretical foundation comprehensively, and then analyzes the environment of the construction of the carbon accounting system. The focus of the article is to build enterprise carbon accounting system, it covers the confirmation and measurement, record and information disclosure of the enterprise carbon accounting on the way of low carbon economy, its core is the processing of carbon emission rights, information disclosure mode and content, etc.; The purpose of this paper is to build enterprise carbon accounting system which is suitable for China’s national conditions, in order to provide certain reference and theoretical support for the low carbon economy development of our country.

  5. Analysis of responses to the microgeneration strategy and low carbon buildings programme consultation

    Energy Technology Data Exchange (ETDEWEB)

    Gibbard, J.; Long, S.; McCartney, K.; Rushton, K.

    2005-10-15

    This report summarises and analyses the written responses to the consultation document, 'Microgeneration Strategy and Low Carbon Buildings Programme', issued by the Department of Trade and Industry (DTI) in June 2005. Responses were received from 204 different organisations representing 29 stakeholder groups. The consultation document contained 41 core questions divided into eight sections: general; product development and deployment; communications; economics; installation; Low Carbon Buildings Programme; physical infrastructure; and local authorities and regional bodies. In the analysis, the responses to these questions were categorised according to whether they represented a 'clear consensus', a 'majority view', 'supporting themes' and 'divergent themes'. Using these categories, stakeholder agreement on the eight strategic issues is summarised in a matrix. The report is divided into three sections: introduction; summary of responses; and key findings. The respondents are listed in an appendix. Another appendix reproduces the consultation questions.

  6. Low Carbon Grid Study: Analysis of a 50% Emission Reduction in California

    Energy Technology Data Exchange (ETDEWEB)

    Brinkman, Gregory [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ehlen, Ali [Center for Energy Efficiency and Renewable Technologies, Sacramento, CA (United States); Caldwell, James H. [Center for Energy Efficiency and Renewable Technologies, Sacramento, CA (United States)

    2016-01-07

    The California 2030 Low Carbon Grid Study (LCGS) analyzes the grid impacts of a variety of scenarios that achieve 50% carbon emission reductions from California's electric power sector. Impacts are characterized based on several key operational and economic metrics, including production costs, emissions, curtailment, and impacts on the operation of gas generation and imports. The modeling results indicate that achieving a low-carbon grid (with emissions 50% below 2012 levels) is possible by 2030 with relatively limited curtailment (less than 1%) if institutional frameworks are flexible. Less flexible institutional frameworks and a less diverse generation portfolio could lead to higher curtailment (up to 10%), operational costs (up to $800 million higher), and carbon emissions (up to 14% higher).

  7. An Empirical Study on Transit-Oriented Low-Carbon Urban Land Use Planning

    DEFF Research Database (Denmark)

    Dou, Yi; Luo, Xiao; Dong, Liang;

    2016-01-01

    Low-carbon urban development is a hot spot of global concerns for fighting against climate change for China, transportation sector has a significant contribution to urban CO2 emissions, while the emissions are still increasing. Transit-Oriented Development (TOD) strategies provide a novel approac...... for urban planners to facilitate the urban carbon mitigation from transportation sector in long-term. While TOD strategies are emerging cases, they are merely qualitatively discussed in China, lacking practical indicators and quantitative verification for supporting the real urban plan...... the layer structure changes and residents migration at about 1km accuracy. Secondly, accessibility was selected as an indicator for urban transportation and estimated by method based on Time Cost Weighted Distance. Finally, the effectiveness of TOD was investigated by evaluating the integration between...... in Shanghai, as well as the practical guidance to low carbon urban planning in developing countries....

  8. Study on Chinese model of low carbon economy-energy-electricity-environment

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Zhaoguang

    2010-09-15

    With the successful experience on energy efficiency in the past 30 years in China, it can be summarized as Energy Usage Management(EUM) and Integrated Resource Strategic Planning(IRSP). They will play essential role in Low Carbon Economy. The model of Low Carbon Economy-Energy-Electricity-Environment and an outlook of Chinese economic growth, energy-electricity demand, and renewable energy generation have been studied in this paper. It has been shown that China would save energy 4.38 billion toe and reduce CO2 emission 16.55 billion ton by EUM, and would save energy 1.5 billion toe and reduce CO2 emission 5.7 Btons by IRSP during 2010-2030.

  9. Bringing the Low-Carbon Agenda to China: A Study in Transnational Policy Diffusion

    Directory of Open Access Journals (Sweden)

    Andreas Hofem

    2013-01-01

    Full Text Available This study traces the transnational interactions that contributed to introducing the low-carbon economy agenda into Chinese policymaking. A microprocessual two-level analysis (outside-in as well as inside-access is employed to analyse transnational and domestic exchanges. The study provides evidence that low-carbon agenda-setting – introduced by transnational actors, backed by foreign funding, promoted by policy entrepreneurs from domestic research institutes, propelled by top-level attention, but only gradually and cautiously adopted by the government bureaucracy – can be considered a case of effective transnational diffusion based on converging perceptions of novel policy challenges and options. Opinion leaders and policy-brokers from the government-linked scientific community functioned as effective access points to the Chinese government’s policy agenda.

  10. Opportunities and challenges for innovation in the design of low-carbon energy technologies

    DEFF Research Database (Denmark)

    Bjarklev, Araceli; Kjær, Tyge; Andersen, Jan;

    2012-01-01

    Footprint, concepts and tools from Life Cycle Assessment, and relevant elements from eco-efficiency theoretical frameworks. Often systemic approaches tend to be driven by completely rational models. However, our main contribution is to consider a more holistic approach that also includes socio......Though there is broad consensus that one of the solutions to the current environmental challenge will be based on the use of low-carbon technologies, and even though there is a big potential to turn to a more sustainable design and innovation, there are several elements that need to be taken...... as a study object and discusses the question: What are the main possibilities and challenges when designing low-carbon illumination technologies? To answer this question, we use a systemic approach including environmental, economic, energy and political issues using relevant concepts from the Ecological...

  11. An Optimal Allocation Model of Public Transit Mode Proportion for the Low-Carbon Transportation

    Directory of Open Access Journals (Sweden)

    Linjun Lu

    2015-01-01

    Full Text Available Public transit has been widely recognized as a potential way to develop low-carbon transportation. In this paper, an optimal allocation model of public transit mode proportion (MPMP has been built to achieve the low-carbon public transit. Optimal ratios of passenger traffic for rail, bus, and taxi are derived by running the model using typical data. With different values of traffic demand, construction cost, travel time, and accessibilities, MPMP can generate corresponding optimal ratios, benefiting decision impacts analysis and decision makers. Instead of considering public transit as a united system, it is separated into units in this paper. And Shanghai is used to test model validity and practicality.

  12. Chinese energy policy progress and challenges in the transition to low carbon development, 2006-2013

    Directory of Open Access Journals (Sweden)

    Larissa Basso

    2014-01-01

    Full Text Available If the world is not to jeopardize the chances for human life on Earth, climate change must be mitigated; therefore, achieving low carbon development is crucial. China is the world's greatest GHG emitter, energy producer and energy consumer; investigating its energy-climate policy developments and international positions are of utmost importance to understand and tackle current stumbling blocks of the global energy and climate governance.

  13. Tackling climate change through community: the politics and practice of the low carbon communities challenge

    OpenAIRE

    Hauxwell-Baldwin, Richard

    2013-01-01

    Despite claims by academics and policymakers that community may offer a potentially useful context through which to tackle climate change, there is limited empirical evidence to support such an assertion. This thesis sets out to address that gap. Drawing on theories of the governance of environmental change, community, social interaction, and governmentality, it presents a qualitative case-study of the Low Carbon Communities Challenge (LCCC). The LCCC was a United Kingdom governme...

  14. Low carbon technology performance vs infrastructure vulnerability: analysis through the local and global properties space.

    Science.gov (United States)

    Dawson, David A; Purnell, Phil; Roelich, Katy; Busch, Jonathan; Steinberger, Julia K

    2014-11-04

    Renewable energy technologies, necessary for low-carbon infrastructure networks, are being adopted to help reduce fossil fuel dependence and meet carbon mitigation targets. The evolution of these technologies has progressed based on the enhancement of technology-specific performance criteria, without explicitly considering the wider system (global) impacts. This paper presents a methodology for simultaneously assessing local (technology) and global (infrastructure) performance, allowing key technological interventions to be evaluated with respect to their effect on the vulnerability of wider infrastructure systems. We use exposure of low carbon infrastructure to critical material supply disruption (criticality) to demonstrate the methodology. A series of local performance changes are analyzed; and by extension of this approach, a method for assessing the combined criticality of multiple materials for one specific technology is proposed. Via a case study of wind turbines at both the material (magnets) and technology (turbine generators) levels, we demonstrate that analysis of a given intervention at different levels can lead to differing conclusions regarding the effect on vulnerability. Infrastructure design decisions should take a systemic approach; without these multilevel considerations, strategic goals aimed to help meet low-carbon targets, that is, through long-term infrastructure transitions, could be significantly jeopardized.

  15. A Low Carbon Development Guide for Local Government Actions in China

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Nina; Zhou, Nan; Price, Lynn; Ohshita, Stephanie

    2011-05-01

    Local level actions are crucial for achieving energy-saving and greenhouse gas emission reduction targets. Yet it is challenging to implement new policies and actions due to a lack of information, funding, and capacity. This is particularly the case in developing countries such as China. Even though national energy intensity and carbon intensity targets have been set, most local governments do not have the knowledge regarding actions to achieve the targets, the cost-effectiveness of policies, the possible impact of policies, or how to design and implement a climate action plan. This paper describes a guidebook that was developed to motivate and provide local governments in China with information to create an action plan to tackle climate change and increase energy efficiency. It provides a simple step-by-step description of how action plans can be established and essential elements to be included - from preparing a GHG emission inventory to implementation of the plan. The guidebook also provides a comprehensive list of successful policies and best practices found internationally and in China to encourage low carbon development in industry, buildings, transportation, electric power generation, agriculture and forestry. This paper also presents indicators that can be used to define low-carbon development, as well as to evaluate the effectiveness of actions taken at an aggregated (city) level, and at a sectoral or end use level. The guidebook can also be used for low carbon development by local governments in other developing countries.

  16. Policy Choice for Urban Low-carbon transportation in Beijing: Scenario Analysis Based on LEAP model

    Science.gov (United States)

    Zhang, Yu

    2016-04-01

    Beijing is a fast developing megacity with serious traffic problems, such as high energy consumption, high CO2 emission and traffic congestion. The coming 13th Five-Year Plan for Beijing economic and social development will focus on the low-carbon transportation policy to achieve the urban traffic sustainable development. In order to improve the feasibility of urban low-carbon transportation policies, this paper analyzes the future trends of CO2 emissions from transportation of Beijing. Firstly, five policies scenarios are developed according to the coming Beijing 13th Five-Year Plan, including the "Business As Usual (BAU)", the "Public Transportation Priority(PTP)", the "New Energy Vehicle(NEV)", the "Active Transportation(AT)", the "Private Car Regulation(PCR)" and the "Hybrid Policy(HP)". Then the Long-range Energy Alternatives Planning System(LEAP model) framework is adopted to estimate CO2 emission under given policies scenarios up to year 2020 and analyze the implications. The results demonstrate that the low-carbon transportation policies can reduce CO2 emission effectively. Specifically, the "Hybrid Policy(HP)" has the best performance. In terms of single policy effect, the "Private Car Regulation(PCR)" comes first followed by the "Public Transportation Priority(PTP)".

  17. Informed public preferences for electricity portfolios with CCS and other low-carbon technologies.

    Science.gov (United States)

    Fleishman, Lauren A; De Bruin, Wändi Bruine; Morgan, M Granger

    2010-09-01

    Public perceptions of carbon capture and sequestration (CCS) and other low-carbon electricity-generating technologies may affect the feasibility of their widespread deployment. We asked a diverse sample of 60 participants recruited from community groups in Pittsburgh, Pennsylvania to rank 10 technologies (e.g., coal with CCS, natural gas, nuclear, various renewables, and energy efficiency), and seven realistic low-carbon portfolios composed of these technologies, after receiving comprehensive and carefully balanced materials that explained the costs and benefits of each technology. Rankings were obtained in small group settings as well as individually before and after the group discussions. The ranking exercise asked participants to assume that the U.S. Congress had mandated a reduction in carbon dioxide emissions from power plants to be built in the future. Overall, rankings suggest that participants favored energy efficiency, followed by nuclear power, integrated gasification combined-cycle coal with CCS and wind. The most preferred portfolio also included these technologies. We find that these informed members of the general public preferred diverse portfolios that contained CCS and nuclear over alternatives once they fully understood the benefits, cost, and limitations of each. The materials and approach developed for this study may also have value in educating members of the general public about the challenges of achieving a low-carbon energy future.

  18. Effect of Metal Additives on Performance of Low-Carbon Magnesia-Carbon Materials

    Institute of Scientific and Technical Information of China (English)

    PENG Xiaoyan; LI Lin; HE Zhiyong; LIU Kaiqi; WANG Bingjun

    2007-01-01

    In this paper, both oxidation and corrosion resistance of low-carbon magnesia-carbon materials containing 4.0wt% graphite with metallic Al and Mg-Al alloy powders as antioxidants were investigated. Meanwhile,the microstructures of samples corroded by slag were observed with optical microscope as well. The test results revealed the properties of oxidation and corrosion resistance of low-carbon magnesia-carbon materials could be improved obviously by adding metal Al powder and Mg-Al alloy powder. The rule of improving oxidation resistance was illegibility when metal Al powder and Mg-Al alloy powder were added together. It was harmful to corrosion resistance by mixed adding metal Al powder and Mg-Al alloy powder into the materials, at the same time, the corrosion resistance would decreased with the increasing of Mg-Al alloy content. The corrosion resistance of samples with 0.5wt% or 3.0wt% Mg-Al alloy was better. The oxidation resistance and corrosion resistance of materials with metal Al or Mg-Al alloy respectively were better than that with mixed metal Al and Mg-Al alloy. As a result, Mg-Al alloy was more suitable for low-carbon composite materials than metal Al as additives.

  19. The necessity to focus on the development of low carbon cities in urban management structure

    Directory of Open Access Journals (Sweden)

    Azam Mohammad Bagheri

    2016-06-01

    Full Text Available Urbanization is developed along with the economic growth and development of countries. This phenomenon has led to increasing the energy consumption in urban areas and consequently, the emission of greenhouse gases. Increasing greenhouse gas emissions with carbon source in urban areas and its adverse effects due to universality have affected all countries. This became a concern for the international community. Thus, the idea of low-carbon cities has been raised at the international level. Efficient use of energy, better use of public transportation systems, improving recycling and increasing public awareness are the important factors in achieving the low-carbon cities. Urbanization is increased in all developing countries in the process of moving on the path of economic growth and development. In this path, our country is faced with rapidly increasing urbanization. Some shortcomings in urban management created many problems such as environmental problems especially for big cities. Due to the importance of sustainable urban management and urban development, focusing on the establishment of a comprehensive program to reduce carbon emissions in cities is a prerequisite for the development of public transport increasing the efficiency of energy consumption, financing the emission reduction projects, improving the recycling system of municipal solid waste on the role of urban management and taking a step in the direction of low-carbon cities. Thus, developing the carbon emission reducing plans is inevitable in urban management structure along with the growth and development of cities.

  20. Catalyzing strategic transformation to a low-carbon economy. A CCS roadmap for China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hengwei; Gallagher, Kelly Sims [Energy Technology Innovation Policy, Belfer Center for Science and International Affairs, John F. Kennedy School of Government, Harvard University, 79 John F. Kennedy Street, Cambridge, MA 02138 (United States)

    2010-01-15

    China now faces the three hard truths of thirsting for more oil, relying heavily on coal, and ranking first in global carbon dioxide (CO{sub 2}) emissions. Given these truths, two key questions must be addressed to develop a low-carbon economy: how to use coal in a carbon-constrained future? How to increase domestic oil supply to enhance energy security? Carbon Capture and Storage (CCS) may be a technological solution that can deal with today's energy and environmental needs while enabling China to move closer to a low-carbon energy future. This paper has been developed to propose a possible CCS roadmap for China. To develop the roadmap, we first explore major carbon capture opportunities in China and then identify critical CCS-enabling technologies, as well as analyze their current status and future prospects. We find that coal gasification or polygeneration in combination with CCS could be a nearly unbeatable combination for China's low-carbon future. Even without CCS, gasification offers many benefits: once coal is gasified into syngas, it can be used for many different purposes including for alternative fuels production, thereby increasing the domestic oil supply and the flexibility of the energy system. (author)

  1. Catalyzing strategic transformation to a low-carbon economy: A CCS roadmap for China

    Energy Technology Data Exchange (ETDEWEB)

    Liu Hengwei, E-mail: hengwei_liu@hks.harvard.ed [Energy Technology Innovation Policy, Belfer Center for Science and International Affairs, John F. Kennedy School of Government, Harvard University, 79 John F. Kennedy Street, Cambridge, MA 02138 (United States); Gallagher, Kelly Sims [Energy Technology Innovation Policy, Belfer Center for Science and International Affairs, John F. Kennedy School of Government, Harvard University, 79 John F. Kennedy Street, Cambridge, MA 02138 (United States)

    2010-01-15

    China now faces the three hard truths of thirsting for more oil, relying heavily on coal, and ranking first in global carbon dioxide (CO{sub 2}) emissions. Given these truths, two key questions must be addressed to develop a low-carbon economy: how to use coal in a carbon-constrained future? How to increase domestic oil supply to enhance energy security? Carbon Capture and Storage (CCS) may be a technological solution that can deal with today's energy and environmental needs while enabling China to move closer to a low-carbon energy future. This paper has been developed to propose a possible CCS roadmap for China. To develop the roadmap, we first explore major carbon capture opportunities in China and then identify critical CCS-enabling technologies, as well as analyze their current status and future prospects. We find that coal gasification or polygeneration in combination with CCS could be a nearly unbeatable combination for China's low-carbon future. Even without CCS, gasification offers many benefits: once coal is gasified into syngas, it can be used for many different purposes including for alternative fuels production, thereby increasing the domestic oil supply and the flexibility of the energy system.

  2. Research on Price of Railway Freight Based on Low-Carbon Economy

    Directory of Open Access Journals (Sweden)

    Fenling Feng

    2016-01-01

    Full Text Available Transportation is one of the major energy consumption and carbon emission industries. Railway transport is a typical low-carbon transport. To accelerate the green low-carbon transportation development and improve the railway market share, this paper defines the concept of carbon saving profit to study the price of railway freight after the government functions were separated from railway enterprise management. First, taking full account of market factors and on the principle of utility maximization and maximum likelihood method, the sharing ratio model of transportation modes is established. Then consideration is given to both the profit of railway enterprises and social benefits, and income maximization model of railway freight based on low-carbon economy is established. The model can scientifically guide the transportation users who prefer to use resource-saving and environmental-friendly transportation modes, optimize transportation structure, and comprehensively improve the efficiency of transportation system. Finally, case analysis is conducted to verify the rationality and validity of the model, and reference for the rail freight pricing is provided.

  3. Ecological Network Analysis for a Low-Carbon and High-Tech Industrial Park

    Directory of Open Access Journals (Sweden)

    Yi Lu

    2012-01-01

    Full Text Available Industrial sector is one of the indispensable contributors in global warming. Even if the occurrence of ecoindustrial parks (EIPs seems to be a good improvement in saving ecological crises, there is still a lack of definitional clarity and in-depth researches on low-carbon industrial parks. In order to reveal the processes of carbon metabolism in a low-carbon high-tech industrial park, we selected Beijing Development Area (BDA International Business Park in Beijing, China as case study, establishing a seven-compartment- model low-carbon metabolic network based on the methodology of Ecological Network Analysis (ENA. Integrating the Network Utility Analysis (NUA, Network Control Analysis (NCA, and system-wide indicators, we compartmentalized system sectors into ecological structure and analyzed dependence and control degree based on carbon metabolism. The results suggest that indirect flows reveal more mutuality and exploitation relation between system compartments and they are prone to positive sides for the stability of the whole system. The ecological structure develops well as an approximate pyramidal structure, and the carbon metabolism of BDA proves self-mutualistic and sustainable. Construction and waste management were found to be two active sectors impacting carbon metabolism, which was mainly regulated by internal and external environment.

  4. Green and sustainable City will become the development objective of China's Low Carbon City in future.

    Science.gov (United States)

    Li-Qun, Liu; Chun-Xia, Liu; Yun-Guang, Gao

    2014-01-14

    Environmental pollution and greenhouse gas emissions are becoming significant environmental issues in China, thus the sustainable development and revival of the country is impossible using the conventional path of encouraging economic growth at the expense of the environment. In response to the global warming, the prices of the traditional energy rise considerably, and a series of environmental problems, China must improve its own mode of economic development. Hundreds of Chinese cities have billions of square meters of buildings and most industry and the annual energy demand is an astronomical figure. China's government is facing increasing pressure in the low carbon international backdrop, and the low carbon city becomes the inevitable developmental direction of Chinese city in the foreseeable future. The description is first centered on energy structure/energy consumption per unit/urbanized status, and urban energy consumption status, and then concerned with the efforts and measures of Chinese government, to realize the energy saving. Finally, we present the developmental prospect and barriers and the promotion measures related to the low carbon city under the government policy, financial incentives and funding supports, etc.

  5. Carbon Diffusion in Hot Strips of Low Carbon Steel Produced by CSP Line under Different Thermal Histories

    Institute of Scientific and Technical Information of China (English)

    Hao YU; Hao REN; Yonglin KANG; Kelu WANG

    2005-01-01

    Two experiments were carried out on the same compact strip production (CSP) line, which differs in that one of them experienced γ→α→γ* thermal history. The differences in microstructure, precipitation, misorientation etc between two experiments were investigated by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron back-scattered diffraction (EBSD) and positron annihilation technique (PAT). The carbon concentration in matrix is more inhomogeneous in the experiment than that with γ→α→γ* thermal history. The specific precipitation characteristic in the experiment without γ→α→γ* thermal history is discussed on the basis of different carbon diffusion behavior and interaction between dislocation and excess carbon.

  6. Self-evaluation System for Low carbon Industrial Park--A Case Study of TEDA Industrial Park in Tianjin

    Science.gov (United States)

    Wenyan, W.; Fanghua, H.; Ying, C.; Ouyang, W.; Yuan, Q.

    2013-12-01

    Massive fossil fuel burning caused by industrialization development is one major reason of global climate change. After Copenhagen climate summit, the studies of low-carbon city gain attentions from many countries. On 25th Nov. 2009, the State Council executive meeting announced that by 2020 China will reduce the carbon dioxide emissions per unit of GDP by 40% to 45% compared with the level of 2005. Industrial Park as an important part of city, has developed rapidly in recent years, and turns into a key element and an alternative mechanism to achieve emission reduction target. Thus, establishing a low carbon development model for industrial park is one of the most effective ways to build sustainable low carbon cities. By adopting the self-evaluation system of low carbon industrial park, this research aims to summarize the low carbon concept in industrial park practice. According to The Guide for Low Carbon Industrial Development Zones, the quantitative evaluation system is divided into 4 separate categories with 23 different quantitative indicators. The 4 categories include: 1) energy and GHG management (weigh 60%), 2) circular economy and environmental protection (weigh 15%), 3) administration and incentive mechanisms of industrial parks (weigh 15%), and 4) planning and urban forms (weigh 10%). By going through the necessary stages and by leading continuous improvements low carbon development goals can be achieved. Tianjin TEDA industrial park is selected as one case study to conduct an assessment on TEDA low-carbon development condition. Tianjin TEDA Industrial Park is already an ecological demonstration industrial park in China, with good foundations on environmental protection, resource recycling, etc. Based on the self-evaluation system, the indicators, such as the energy using efficiency and the degree of land intensive utilization, are also analyzed and assessed. Through field survey and data collection, in accordance with the quantitative self

  7. Weldability and SAW welding wire of X80 pipeline steel

    Institute of Scientific and Technical Information of China (English)

    Huang Zhijun; Hu Lunji; Miao Kai; Zhang Xiaofeng; Chen Fu

    2006-01-01

    Weldability test was carried out on the newly developed fine grain, low sulphur, high strength and high toughness pipeline steel of X80 and its matching SA W wire. Test of maximum hardness in welding heat-affected zone and test of Y groove cracking show that X80 steel features low hardenability and good cracking resistance. The submerged arc welding joint made with the newly developed low carbon and multi-alloyed SA W wire of WGX2 exhibits a little higher strength than the base metal, qualified bending performance, under maximum limitation hardness and good impact toughness, which can completely meet the technical requirement of X80 steel. Despite somewhat coarsening the grain size in welding heat-affected zone is still much finer than that of traditional steels, and the microstructure in weld metal is almost full acicular ferrite. The results show that X80 steel and WGX2 wire are of great weldability.

  8. 高硼低碳耐磨合金磨料磨损性能研究%Study on Abrasive Wear Performance of High Boron Low Carbon Wear-resistant Alloy

    Institute of Scientific and Technical Information of China (English)

    麻健梅; 王顺波; 苏广才; 汤宏群

    2013-01-01

    借助光学显微镜和SEM电镜观察,运用磨损试验手段及对比研究法,研究了高硼低碳耐磨合金的磨料磨损性能.结果表明,在中、低冲击工况下,高硼低碳耐磨合金的磨损质量损失、相对磨损率均小于高铬铸铁和高锰钢,且磨面磨损形成的沟槽少,压坑小,这显示出了良好的耐磨料磨损性.%The high boron low carbon wear-resistant alloy abrasive wear performance was researched by OM, SEM observation, wear test methods and comparision approach. The results show that in the medium or low impact conditions, the wear mass loss and relative wear rate of high boron low carbon wear-resistant alloy are less than that of high chromium cast iron and high manganese steel. The number of the wear grooves and the pits on the wear surface morphology is smaller, which shows the good characteristics in abrasive wear performance of high boron low carbon wear-resistant alloy.

  9. Going Clean - The Economics of China's Low-carbon Development

    Energy Technology Data Exchange (ETDEWEB)

    Hallding, Karl; Thai, Helen; Han, Guoyi; Olsson, Marie; Kartha, Sivan (Stockholm Environment Inst. (Sweden)); Eklund, Klas (SEB, Stockholm (Sweden)); SU Ming (Peking Univ. (China)); Cao Jing (Tsinghua Univ. (China)); Luderer (Potsdam Inst. for Climate Impact (Germany))

    2009-11-15

    This report shows that China can achieve the transition to a low-carbon economy. China can make these emissions reductions within the tight constraints of a global 2 deg C target while still meeting development and economic growth goals over the next four decades. There are strong mitigation potentials in the building, industry, transport and electricity generation sectors. China would benefit from early mitigation, but immediate action is critical for the world to have a reasonable chance of keeping warming below the 2 deg C target. Such a transition would also be an essential part of China's modernisation. A low-carbon transition presents opportunities for China to improve its energy security and move its economy up the value chain in the production of international goods and services. A low-carbon China is a country with a larger service sector, more advanced labour skills and less environmental degradation. During this transition, new, green job opportunities will emerge, and support an overall shift to a low-carbon economy. Active labour market and social policies, vocational training and upgrading of skills are imperative to facilitate this modernisation and reduce the impact of jobs lost in resource-intensive industries. With today's low price on carbon emissions, the incentives for a low-carbon transition are not sufficiently strong. Consumption and production patterns must be steered in a more resource-sustainable direction. A first step is to phase out subsidies on fossil fuels. Another is to place a price on carbon, either through a carbon tax or a cap-and-trade system, which would create incentives for companies and individuals to produce and consume less carbon-intensive goods and services, and to undertake abatement opportunities to reduce their overall carbon footprint. Advancing technology and innovation need to be fundamental, shared policy objectives in this transition. Early investment reduces costs and paves the way for large

  10. Development of advanced low alloy steel for nuclear RPV

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H. C.; Shin, K. S.; Lee, S. H.; Lee, B. J. [Seoul National Univ., Seoul (Korea)

    2000-04-01

    Low carbon low alloy steels are used in nuclear power plants as pressure vessel, steam generator, etc. Nuclear pressure vessel material requires good combination of strength/ toughness, good weldability and high resistance to neutron irradiation and corrosion fatigue. For SA508III steels, most widely used in the production of nuclear power plant, attaining toughness is more difficult than strength. When taking into account the loss of toughness due to neutron irradiation, attaining as low transition temperature as possible prior to operation is a critical task in the production of nuclear pressure vessels. In the present study, we investigated detrimental microstructural features of SA508III steels to toughness, then alloy design directions to achieve improved mechanical properties were devised. The next step of alloy design was determined based on phase equilibrium thermodynamics and obtained results. Low carbon low alloy steels having low transition temperatures with enough strength and hardenability were developed. Microstructure and mechanical properties of HAZ of SA508III steels and alloy designed steels were investigated. 22 refs., 147 figs., 38 tabs. (Author)

  11. Aging phenomena in high-Si steels studied by internal friction

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, D. [Department of Metallurgy and Materials Science, Ghent University, Technologiepark 903, B-9052 Gent (Belgium) and Department of Subatomic and Radiation Physics, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium)]. E-mail: Daniel.Ruiz@UGent.be; Rivera-Tovar, J.L. [Department of Metallurgy and Materials Science, Ghent University, Technologiepark 903, B-9052 Gent (Belgium); Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, A.P. 149-F, 66451 San Nicolas de los Garza, N.L. (Mexico); Segers, D. [Department of Subatomic and Radiation Physics, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); Vandenberghe, R.E. [Department of Subatomic and Radiation Physics, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium); Houbaert, Y. [Department of Metallurgy and Materials Science, Ghent University, Technologiepark 903, B-9052 Gent (Belgium)

    2006-12-20

    Si-steels with various Si-contents (1.9-5.6 wt.%) have been analyzed by internal friction and compared with an ultra-low carbon steel. Measurements have been carried out immediately after different thermomechanical treatments to study a believed aging phenomenon. Adding Si lowers the Snoek peak of carbon and produces a new peak associated to the formation of Si-C pairs. For Si contents higher than 4.6 wt.%, another peak appears at very low frequencies, which can be attributed to a Zener relaxation of Si-atom pairs. A room-temperature aging effect has been detected in the Si-steels, but not in the ultra-low carbon steel. This aging is caused by the migration of C atoms to the structural defects and by formation of short-range order in the Fe-Si solution.

  12. Practice of Developing Low-carbon Leisure Agriculture in Agricultural Sci-tech Experiment and Demonstration Park: A Case Study of Xinglong Tropical Botanical Park

    Institute of Scientific and Technical Information of China (English)

    Huan; OUYANG; Huasong; WU; Aiqin; LIU; Huan; YU; Hongmei; FU

    2013-01-01

    The Agricultural Science and Technology Experiment and Demonstration Park,as a unique tourist scenic spot,is a new model for the development of low-carbon leisure agriculture.In this paper,with Xinglong Tropical Botanical Park as a study case,the practice of developing a model of low-carbon agricultural science and technology tourism in the park is explored.Main measures for developing low-carbon leisure agriculture in Agricultural Science and Technology Experiment and Demonstration Park are summarized,including development of low carbon attractors,construction of low carbon facilities,strengthening low-carbon management,building low-carbon environment and so on,according to analysis on the models for development of low-carbon agricultural science tourism in this park.

  13. Corrosion Performance of Carbon Steel in Micelle-containing Cement Extract

    OpenAIRE

    Hu, J; Koleva, D. A.; Wit, J.H.W. de; Petrov, P; Breugel, K. van

    2010-01-01

    This study presents the results from a preliminary investigation on the corrosion behavior of low carbon steel in cement extract (CE) in the presence of very low concentration polymeric nanoaggregates (PEO113-b-PS70 micelles). The steel electrodes were investigated in Cl--containing CE as corrosion medium, compared to chloride-free CE as a reference case. The results from the electrochemical measurements (Electrochemical Impedance Spectroscopy (EIS) and Potentio-dynamic Polarization (PDP)) in...

  14. Research on flow stress in ferrite deformation of a Ti-IF steel

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The experiments of the ferrite warm deformation of ultra-low carbon (ULC) Ti-IF steel were carried out on a hot simulator and the influences of deformation temperature, strain, and strain rate on the flow stress were analyzed. New flow stress models suitable to ferrite warm forming of Ti-IF steel were given on the basis of analyzing the influence of deformation technology parameters on the flow stress.

  15. Evaluation of Friction Stir Processing of HY-80 Steel Under Wet and Dry Conditions

    OpenAIRE

    Young, Garth William II

    2012-01-01

    This thesis describes the microstructural and mechanical property changes associated with Friction Stir Processing (FSP) of HY-80 steel under dry and underwater conditions. HY-80 is a low-carbon alloy steel that is used in a quenched and tempered condition and is highly susceptible to hydrogen assisted cracking associated with conventional fusion welding. FSW/P (400 RPM/ 2 IPM) was conducted using a polycrystalline cubic boron nitride tool having a pin length of 6.35 mm. Two sets ...

  16. Scenario analysis of energy-based low-carbon development in China.

    Science.gov (United States)

    Zhou, Yun; Hao, Fanghua; Meng, Wei; Fu, Jiafeng

    2014-08-01

    China's increasing energy consumption and coal-dominant energy structure have contributed not only to severe environmental pollution, but also to global climate change. This article begins with a brief review of China's primary energy use and associated environmental problems and health risks. To analyze the potential of China's transition to low-carbon development, three scenarios are constructed to simulate energy demand and CO₂ emission trends in China up to 2050 by using the Long-range Energy Alternatives Planning System (LEAP) model. Simulation results show that with the assumption of an average annual Gross Domestic Product (GDP) growth rate of 6.45%, total primary energy demand is expected to increase by 63.4%, 48.8% and 12.2% under the Business as Usual (BaU), Carbon Reduction (CR) and Integrated Low Carbon Economy (ILCE) scenarios in 2050 from the 2009 levels. Total energy-related CO₂ emissions will increase from 6.7 billiontons in 2009 to 9.5, 11, 11.6 and 11.2 billiontons; 8.2, 9.2, 9.6 and 9 billiontons; 7.1, 7.4, 7.2 and 6.4 billiontons in 2020, 2030, 2040 and 2050 under the BaU, CR and ILCE scenarios, respectively. Total CO₂ emission will drop by 19.6% and 42.9% under the CR and ILCE scenarios in 2050, compared with the BaU scenario. To realize a substantial cut in energy consumption and carbon emissions, China needs to make a long-term low-carbon development strategy targeting further improvement of energy efficiency, optimization of energy structure, deployment of clean coal technology and use of market-based economic instruments like energy/carbon taxation.

  17. Alpine hydropower in a low carbon economy: Assessing the local implication of global policies

    Science.gov (United States)

    Anghileri, Daniela; Castelletti, Andrea; Burlando, Paolo

    2016-04-01

    In the global transition towards a more efficient and low-carbon economy, renewable energy plays a major role in displacing fossil fuels, meeting global energy demand while reducing carbon dioxide emissions. In Europe, Variable Renewable Sources (VRS), such as wind and solar power sources, are becoming a relevant share of the generation portfolios in many countries. Beside the indisputable social and environmental advantages of VRS, on the short medium term the VRS-induced lowering energy prices and increasing price's volatility might challenge traditional power sources and, among them, hydropower production, because of smaller incomes and higher maintenance costs associated to a more flexible operation of power systems. In this study, we focus on the Swiss hydropower sector analysing how different low-carbon targets and strategies established at the Swiss and European level might affect energy price formation and thus impact - through hydropower operation - water availability and ecosystems services at the catchment scale. We combine a hydrological model to simulate future water availability and an electricity market model to simulate future evolution of energy prices based on official Swiss and European energy roadmaps and CO2 price trends in the European Union. We use Multi-Objective optimization techniques to design alternative hydropower reservoir operation strategies, aiming to maximise the hydropower companies' income or to provide reliable energy supply with respect to the energy demand. This integrated model allows analysing to which extent global low-carbon policies impact reservoir operation at the local scale, and to gain insight on how to prioritise compensation measures and/or adaptation strategies to mitigate the impact of VRS on hydropower companies in increasingly water constrained settings. Numerical results are shown for a real-world case study in the Swiss Alps.

  18. DISCUSSIONS ON ADVOCATING LOW CARBON AGRICULTURE%提倡低碳的几个问题

    Institute of Scientific and Technical Information of China (English)

    刘巽浩

    2012-01-01

    Low carbon agriculture is a historical necessity. However, it should conform to the reasonable principles and avoid extremalization. Chinese agriculture with a big population and shortage of cultivated land needs to implement the intensive sustainable farming systems that combined high yield with environmental protection. What is called " agriculture low - carbonization" should not be recommended blindly. Based on the author's practice and on - the - spot investigation both in domestic and foreign countries, the relationship between low carbon expenditure and four main agricultural activities, i. e. , farming systems, fertilization, tillage, and forestation, were analyzed and discussed.%农业提倡低碳是历史的必然.提倡低碳必须符合适度、合情、合理的原则,避免极端化.中国农业的特点是人多地少,必须实行高产高效与资源环境兼顾的集约持续农作制,不可盲目地推行所谓“农业低碳化”.该文根据作者多年的实践研究以及国内外考察,围绕着如何适度合情合理提倡低碳的问题,对涉及碳流的4个主要领域,即农作制、施肥、耕作和造林,进行具体的分析与讨论.

  19. Mapping and Measuring European Local Governments’ Priorities for a Sustainable and Low-Carbon Energy Future

    Directory of Open Access Journals (Sweden)

    Stelios Grafakos

    2015-10-01

    Full Text Available The main objective of this article is to assess the priorities of local governments (LGs in Europe regarding climate change mitigation technologies evaluation in the electricity sector and to provide important insights for energy policy design. The study applies a hybrid weighting methodology to elicit LGs’ preferences in a constructive and iterative way regarding the evaluation criteria of low-carbon energy technologies. Furthermore, the study employs three data collection and preference elicitation methods, namely: survey, workshop, and webinar. The study was conducted across thirty one (31 European LGs that were categorized according to three variables: population size, geographical region and gross domestic product (GDP per capita. The analysis shows that “CO2 emissions” is the most important criterion among European LGs, followed by “mortality and morbidity” and “ecosystem damages”. The results illustrate the potential synergies of climate and energy policies for addressing both CO2 emissions and air pollution. It was also found, based on a correlation analysis, that LGs with higher GDP per capita tend to provide higher weights to criteria related to security of energy supply and technological innovation. The current study provides insights on the actual LGs’ priorities that are important to consider during low-carbon energy technologies evaluation and energy policy design. Interestingly, the results of the European LGs’ preferences clearly show that the EU climate policy objectives have reached different levels of governance—and at this particular case, the local level. Furthermore, the developed methodology could be applied at different geographical regions to map other regions’ LG priorities, but also at a group decision making context to elicit relevant stakeholders’ preferences regarding low-carbon energy technologies and policy objectives.

  20. China's Voluntary Mitigation Target and Road of Low-carbon Development

    Institute of Scientific and Technical Information of China (English)

    He Jiankun

    2011-01-01

    China is going through a rapid development stage of industrialization and urbanization.Although tremendous achievements have been made in the aspects of energy conservation,improvement of energy effectiveness and development of new and renewable energies,because of the rapid development of economy,it is difficult to change the huge total amount and fast increase of CO2 emission in the near future.China has to confront the tough challenge to address global climate change.China plans to reduce carbon intensity,that is,CO2 emissions per unit GDP,by 40 to 45% by 2020 compared with the 2005 level.It is a strategic option to coordinate domestic sustainable development with coping with global climate change on the basis of China's national circumstances,representing the core content and key measures for transforming development pattern and realizing low-carbon development.To achieve the target,more capital and technology inputs are required for energy conservation and low-carbon development during the twelfth and Thirteenth Five Year Plan period than in the Eleventh Five Year Plan period.In addition,energy conservation achieved by structural adjustment,industrial upgrading and product value-added improvement is also expected to play a greater role.Therefore,China should strengthen technological innovation,make greater efforts to transform the development pattern,take advantage of the synergistic effect of policies and measures while coping with global climate change and building a domestic tow-oriented society.China should also establish an industrial system characterized by low-carbon emission.Then China will ultimately achieve a win-win situation in both domestic sustainable development and coping with global climate change.

  1. Media discourses of low carbon housing: The marginalisation of social and behavioural dimensions within the British broadsheet press.

    Science.gov (United States)

    Cherry, Catherine; Hopfe, Christina; MacGillivray, Brian; Pidgeon, Nick

    2015-04-01

    Decarbonising housing is a key UK government policy to mitigate climate change. Using discourse analysis, we assess how low carbon housing is portrayed within British broadsheet media. Three distinct storylines were identified. Dominating the discourse, Zero carbon housing promotes new-build, low carbon houses as offering high technology solutions to the climate problem. Retrofitting homes emphasises the need to reduce emissions within existing housing, tackling both climate change and rising fuel prices. A more marginal discourse, Sustainable living, frames low carbon houses as related to individual identities and 'off-grid' or greener lifestyles. Our analysis demonstrates that technical and economic paradigms dominate media discourse on low carbon housing, marginalising social and behavioural aspects.

  2. Transportation Energy Futures Series: Alternative Fuel Infrastructure Expansion: Costs, Resources, Production Capacity, and Retail Availability for Low-Carbon Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Melaina, W. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Heath, Garvin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sandor, Debra [National Renewable Energy Lab. (NREL), Golden, CO (United States); Steward, Darlene [National Renewable Energy Lab. (NREL), Golden, CO (United States); Vimmerstedt, Laura [National Renewable Energy Lab. (NREL), Golden, CO (United States); Warner, Ethan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Webster, Karen W. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-04-01

    The petroleum-based transportation fuel system is complex and highly developed, in contrast to the nascent low-petroleum, low-carbon alternative fuel system. This report examines how expansion of the low-carbon transportation fuel infrastructure could contribute to deep reductions in petroleum use and greenhouse gas (GHG) emissions across the U.S. transportation sector. Three low-carbon scenarios, each using a different combination of low-carbon fuels, were developed to explore infrastructure expansion trends consistent with a study goal of reducing transportation sector GHG emissions to 80% less than 2005 levels by 2050.These scenarios were compared to a business-as-usual (BAU) scenario and were evaluated with respect to four criteria: fuel cost estimates, resource availability, fuel production capacity expansion, and retail infrastructure expansion.

  3. Energy outlook to 2035 in Asia and its pathways towards a low carbon energy system

    Energy Technology Data Exchange (ETDEWEB)

    Komiyama, Ryoichi

    2010-09-15

    This report analyzes energy outlook in Asia and the world to 2035. In Technologically Advanced Scenario, advanced low-carbon technology yields, in 2035, 2,305 Mtoe or 14% of the saving in world primary energy demand and 12.3 Gt or 30% of the reduction in global CO2 emissions compared with the Reference Scenario. In these savings, Asia will account for 58% in the world primary energy reduction and 55% of the world CO2 mitigation, emphasizing immense potential of energy and CO2 saving in Asia and the importance of the deployment of clean energy technology through technology transfer to Asian region.

  4. Low carbon development and poverty alleviation. Options for development cooperation in energy, agriculture and forestry

    Energy Technology Data Exchange (ETDEWEB)

    Funder, M.; Fjalland, J.; Munk Ravnborg, H.; Egelyng, H.

    2009-07-01

    This report presents the main findings of a desk study on 'Climate change mitigation and poverty reduction in developing countries: opportunities for development cooperation'. The main objective of the study is to identify options for combining low carbon development pathways with poverty reduction and economic growth in the Least Developed Countries (LDCs), as part of efforts to target development assistance to address both poverty and global warming problems. The report discusses the pros and cons of climate change mitigation measures that also support poverty alleviation and economic development within the energy, agriculture and forestry sectors. It concludes with a series of recommendations for development cooperation.

  5. Electron Microscope Study of the Microstructure of BIS 812 EMA Submarine Steel

    Science.gov (United States)

    1992-12-01

    steels. For BIS 812 EMA it is therefore possible that a small proportion of the vanadium could occur with niobium carbide precipitated in the...Institute, 204, 702-710. Irvine, J. and Baker, T.N. (1979). Effect of rolling deformation on niobium carbide particle size distribution in low carbon

  6. Feasibility of underwater friction stir welding of HY-80 steel

    OpenAIRE

    Stewart, William Chad

    2011-01-01

    Approved for public release; distribution is unlimited. The purpose of this thesis is to determine the feasibility of underwater friction stir welding (FSW) of high-strength; quench and temper low carbon steels that are susceptible to hydrogen-assisted cracking (HAC). The specific benefits of underwater FSW would be weld repairs of ship and submarine control surfaces and hulls without the need for drydocking and extensive environmental control procedures. A single tool of polycrystallin...

  7. Prototype steel-concrete LEP dipole magnet

    CERN Multimedia

    1981-01-01

    The magnetic field needed in the LEP dipole magnets was rather low, of a fraction of tesla. This lead to the conception of a novel yoke structure consisting of stacks of 1.5 mm thick low-carbon steel laminations spaced by 4.1 mm with the spaces filled with concrete. The excitation coils were also very simple: aluminium bars insulated by polyester boxes in this prototype, by glass-epoxy in the final magnets. For details see LEP-Note 118,1978 and LEP-Note 233 1980. See also 8111529,7908528X.

  8. Effect of Ti(C, N) on Properties of Low-carbon MgO-C Bricks

    Institute of Scientific and Technical Information of China (English)

    QIN Xianpeng; LI Yuanbing; YANG Zhenghong; LI Yawei

    2008-01-01

    The effect of Ti(C, N) on properties of low-carbon MgO-C bricks was investigated. The phase composition and the microstructure of the matrix of low-carbon MgO-C brick containing Ti(C, N) were studied by XRD and SEM analysis together with EDS. The results showed that Ti(C, N) distributed in the matrix of lowcarbon MgO-C brick uniformly after being treated at 1600℃ for 3h in coke powder bed, and Ti(C, N) and MgO formed a solid solution. After the treatment at 1600℃ for 3h in coke powder bed, the bulk density and cold crushing strength of low-carbon MgO-C brick with Ti(C, N) decreased, and the apparent porosity and linear change rate of specimens increased. The oxidation resistance of low-carbon MgO-C brick with Ti(C, N) was superior to that of low-carbon MgO-C brick with no additives, but inferior to that of low-carbon MgO-C brick with Al powder. The slag resistance of the specimen with Ti(C, N) was excellent as well.

  9. On the Notion of Low-Carbon Tourist Consumption%低碳旅游消费观初探

    Institute of Scientific and Technical Information of China (English)

    宋志方

    2012-01-01

    Low-carbon tourism is both a new requirement of environmental protection and a high value orientation of tourist development to benefit the human being. The government, tourist enterprises as well as tourists have an unshirkable responsibility to promote low-carbon tourism. It is required that the whole society unite to develop low-carbon tourist consumption. To raise the awareness of low-carbon tourism and the notion of low-carbon consumption, the tourist enterprises shall provide the tourists with low-carbon tourism experience in such aspects as tousist facilities, modes and so on.%低碳旅游既是环保的新要求,同时又彰显了旅游发展造福人类的最高价值取向。推行低碳旅游,政府、旅游企业以及旅游者都责无旁贷。发展低碳旅游,要社会联动,要培育低碳旅游意识和消费观念。旅游企业要在旅游设施、方式等方面为旅游者提供低碳旅游体验。

  10. Steel Planning

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    China releases a new plan for the iron and steel industry centered on industrial upgrades The new 12th Five-Year Plan (2011-15) for China’s iron and steel industry, recently released on the website of the Ministry of Industry and Information

  11. China's Transition to a Low-Carbon Economy: 2006-2010

    Institute of Scientific and Technical Information of China (English)

    o,~; Li Huimin

    2012-01-01

    China achieved major progress in low-carbon develop- ment during the period of the 11th Five Year Plan (2006-2010). The increasing trend of energy intensity and carbon intensity of the economy as seen prior to 2005 was reversed to a sharp decreas- ing trend, leading to a 19% decrease in energy intensity and 21% decrease in carbon intensity in five years. The enhanced energy efficiency, mostly due to efficiency improvement in power and manufacturing sector, is the major driver of the decrease in carbon intensity of the economy. The development of renewable energy, despite its impressive growth rate, played a minor role because of its small share in the energy mix of the country. Energy con- sumption and energy-related carbon emissions per unit of area in building continued to grow at a lesser rate, which, combined with the fast growth of total building volume, led to fast growth in total energy consumption and carbon emissions in the sector. Similar trend is observed in the transportation sector whose total energy use and carbon emissions continued to grow fast despite slight improvement in energy efficiency. Agricultural energy use expe- rienced a slight change and forestry made a major contribution to carbon sinks. Policy and institutional innovations helped build a solid system of rules for low-carbon development. Improving cost effectiveness of the system remains a major challenge for the next five year plan period.

  12. Greenhouse Gas Emission Accounting and Management of Low-Carbon Community

    Directory of Open Access Journals (Sweden)

    Dan Song

    2012-01-01

    Full Text Available As the major source of greenhouse gas (GHG emission, cities have been under tremendous pressure of energy conservation and emission reduction for decades. Community is the main unit of urban housing, public facilities, transportation, and other properties of city's land use. The construction of low-carbon community is an important pathway to realize carbon emission mitigation in the context of rapid urbanization. Therefore, an efficient carbon accounting framework should be proposed for CO2 emissions mitigation at a subcity level. Based on life-cycle analysis (LCA, a three-tier accounting framework for the carbon emissions of the community is put forward, including emissions from direct fossil fuel combustion, purchased energy (electricity, heat, and water, and supply chain emissions embodied in the consumption of goods. By compiling a detailed CO2 emission inventory, the magnitude of carbon emissions and the mitigation potential in a typical high-quality community in Beijing are quantified within the accounting framework proposed. Results show that emissions from supply chain emissions embodied in the consumption of goods cannot be ignored. Specific suggestions are also provided for the urban decision makers to achieve the optimal resource allocation and further promotion of low-carbon communities.

  13. Low-Carbon Based Multi-Objective Bi-Level Power Dispatching under Uncertainty

    Directory of Open Access Journals (Sweden)

    Xiaoyang Zhou

    2016-06-01

    Full Text Available This research examines a low-carbon power dispatch problem under uncertainty. A hybrid uncertain multi-objective bi-level model with one leader and multiple followers is established to support the decision making of power dispatch and generation. The upper level decision maker is the regional power grid corporation which allocates power quotas to each follower based on the objectives of reasonable returns, a small power surplus and low carbon emissions. The lower level decision makers are the power generation groups which decide on their respective power generation plans and prices to ensure the highest total revenue under consideration of government subsidies, environmental costs and the carbon trading. Random and fuzzy variables are adopted to describe the uncertain factors and chance constrained and expected value programming are used to handle the hybrid uncertain model. The bi-level models are then transformed into solvable single level models using a satisfaction method. Finally, a detailed case study and comparative analyses are presented to test the proposed models and approaches to validate the effectiveness and illustrate the advantages.

  14. The hidden costs of fossil power generation in Indonesia: A reduction approach through low carbon society

    Directory of Open Access Journals (Sweden)

    Muhammad Ery Wijaya

    2010-03-01

    Full Text Available Energy production and consumption is always accompanied with environmental and societal issues. Electricity as onefinal energy form plays an important role in people’s activities. However, the electric utilities have focused on producingelectricity in abundance and with an affordable price. The production of electricity results in undesirable emissions and environmental effects called externalities. This paper assesses the externality cost of electricity production in Indonesia by using the life cycle inventory analysis approach. In 2025, the results show that the total external costs according to the government plan are 42 billion US$. In addition, low carbon society behavior will be introduced into the Indonesian society to reducethe externality cost in the long term Indonesian electricity expansion planning. The results of low carbon society actionsshow that in the long term the Indonesian electricity expansion planning of 34.6 TWh of electricity demand and 7.3 GW of installed capacity can be reduced from these actions. Finally, at the end of the period, these actions are successful, and reducing the total external cost by 2 billion US$.

  15. Low-carbon communities as a context for individual behavioural change

    Energy Technology Data Exchange (ETDEWEB)

    Heiskanen, Eva; Johnson, Mikael; Saastamoinen, Mika [National Consumer Research Centre, P.O. Box 5, 00531 Helsinki (Finland); Robinson, Simon [Manchester Knowledge Capital, Churchgate House, 56 Oxford Street, Manchester, M60 7HJ (United Kingdom); Vadovics, Edina [Green Dependent Sustainable Solutions Association, Eva u. 4, 2100 Goedoelloe (Hungary)

    2010-12-15

    Previous attempts to change energy-related behaviour were targeted at individuals as consumers of energy. Recent literature has suggested that more focus should be placed on the community level and that energy users should be engaged in the role of citizens, and not only that of consumers. This article analyses different types of emerging low-carbon communities as a context for individual behavioural change. The focus is on how these communities offer solutions to problems in previous attempts to change individual behaviour. These problems include social dilemmas, social conventions, socio-technical infrastructures and the helplessness of individuals. Different community types are examined, including geographical communities as well as sector-based, interest-based and smart mob communities. Through four case studies representing each of these community types, we examine how different communities reframe problems on the individual level to reduce carbon emissions. On the basis of an analysis of the strengths and weaknesses of various community solutions, implications are drawn for further research and for the design and support of low-carbon communities. (author)

  16. Innovation of China’s Circular Agricultural Development in the Perspective of Low Carbon Economy

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    On the basis of the concept and characteristics of circular economy, this paper analyzes the restraining factors of China’s circular agricultural development as follows: issues concerning agriculture, countryside and farmers are outstanding; the problems of agricultural resources and agricultural ecological environment are serious; the quality of agricultural products cannot meet the demand of domestic and international market for food. Based on the internal requirements of low carbon economic development, this paper advances four innovative models concerning China’s circular agricultural development as follows: the model of combining planting and breeding of agriculture, the developmental model of leisure and sightseeing, ecological integration model, and the developmental model of reusing agricultural byproducts. Every region should choose or create different circular agricultural model in different domains, in order to better use agricultural resources, reduce the consumption of agricultural energy inputs, reduce the emission of agricultural greenhouse gas, develop low carbon agriculture, and make great contribution for meeting the international challenges and promoting China’s agricultural development.

  17. Supporting Urban Planning of Low-Carbon Precincts: Integrated Demand Forecasting

    Directory of Open Access Journals (Sweden)

    Steffen Lehmann

    2013-12-01

    Full Text Available Waste is a symbol of inefficiency in modern society and represents misallocated resources. This paper outlines an on-going interdisciplinary research project entitled “Integrated ETWW demand forecasting and scenario planning for low-carbon precincts” and reports on first findings and a literature review. This large multi-stakeholder research project develops a shared platform for integrated ETWW (energy, transport, waste and water planning in a low-carbon urban future, focusing on synergies and alternative approaches to urban planning. The aim of the project is to develop a holistic integrated software tool for demand forecasting and scenario evaluation for residential precincts, covering the four domains, ETWW, using identified commonalities in data requirements and model formulation. The authors of this paper are overseeing the waste domain. A major component of the project will be developing a method for including the impacts of household behavior change in demand forecasting, as well as assessing the overall carbon impacts of urban developments or redevelopments of existing precincts. The resulting tool will allow urban planners, municipalities and developers to assess the future total demands for energy, transport, waste and water whilst in the planning phase. The tool will also help to assess waste management performance and materials flow in relation to energy and water consumption and travel behavior, supporting the design and management of urban systems in different city contexts.

  18. Energy at the Frontier: Low Carbon Energy System Transitions and Innovation in Four Prime Mover Countries

    Science.gov (United States)

    Araujo, Kathleen M.

    All too often, discussion about the imperative to change national energy pathways revolves around long timescales and least cost economics of near-term energy alternatives. While both elements certainly matter, they don't fully reflect what can drive such development trajectories. This study explores national energy transitions by examining ways in which four prime mover countries of low carbon energy technology shifted away from fossil fuels, following the first global oil crisis of 1973. The research analyzes the role of readiness, sectoral contributions and adaptive policy in the scale-up and innovations of advanced, alternative energy technologies. Cases of Brazilian biofuels, Danish wind power, French nuclear power and Icelandic geothermal energy are analyzed for a period of four decades. Fundamentally, the research finds that significant change can occur in under 15 years; that technology complexity need not necessarily impede change; and that countries of different governance approaches and consumption levels can effectuate such transitions. This research also underscores that low carbon energy technologies may be adopted before they are competitive and then become competitive in the process. (Copies available exclusively from MIT Libraries, libraries.mit.edu/docs - docs mit.edu)

  19. Climate Change in Central and West Asia. Routes to a More Secure, Low-Carbon Future

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-11-15

    ADB's Central and West Asian countries are Afghanistan, Armenia, Azerbaijan, Georgia, Kazakhstan, the Kyrgyz Republic, Pakistan, Tajikistan, Turkmenistan, and Uzbekistan. Geoclimatic and environmental factors make this region highly vulnerable to the risks and hazards of climate change. For example, accelerated glacial melt has serious implications for agriculture, water supply, and energy generation - problems exacerbated by overexploitation of natural resources. Countries may find it difficult to shift to low-carbon growth, since many have abundant fossil fuel and tend to use energy inefficiently. ADB is responding to these climate hazards and low-carbon pathways with a comprehensive strategy that strengthens policies, governance, and capacity support; expands the use of clean and renewable energy; encourages sustainable transport and urban development; promotes development that will be more resilient to climate change, especially in water-dependent sectors; and manages land use and forests for carbon sequestration. ADB's support is helping its developing member countries face the challenges of climate change and, with partners, is providing innovative solutions, while continuing to work to reduce poverty.

  20. The Geography of Solar Photovoltaics (PV and a New Low Carbon Urban Transition Theory

    Directory of Open Access Journals (Sweden)

    Peter Newton

    2013-06-01

    Full Text Available This paper examines the early phases of a 21st century energy transition that involves distributed generation technologies employing low or zero carbon emission power sources and their take-up within Australia, with particular reference to the major cities and solar photovoltaics (PV. This transition is occurring in a nation with significant path dependency to overcome in relation to fossil fuel use. Tracking the diffusion of solar PV technology within Australia over the past decade provides a basis for assessing those factors underpinning its exponential growth and its associated geography of diffusion. Positive evidence that there are pathways for cities to decarbonise is apparent but there appear to be different pathways for different city forms with lower density suburban areas showing the biggest take-up of household-based energy technologies. This suggests a model for the low carbon urban transition involving combinations of simple technological changes and harder structural changes, depending upon which parts of the urban fabric are in focus. This is being called a New Low Carbon Urban Transition Theory.

  1. Secure and Efficient Electricity Supply. During the Transition to Low Carbon Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    Electricity shortages can paralyse our modern economies. All governments fear rolling black-outs and their economic consequences, especially in economies increasingly based on digital technologies. Over the last two decades, the development of markets for power has produced cost reduction, technological innovation, increased cross border trade and assured a steady supply of electricity. Now, IEA countries face the challenge of maintaining security of electricity supply during the transition to low-carbon economies. Low-carbon policies are pushing electricity markets into novel territories at a time when most of the generation and network capacity will have to be replaced. Most notably, wind and solar generation, now an integral part of electricity markets, can present new operating and investment challenges for generation, networks and the regional integration of electricity markets. In addition, the resilience of power systems facing more frequent natural disasters is also of increasing concern. IEA Ministers mandated the Secretariat to work on the Electricity Security Action Plan (ESAP), expanding to electricity the energy security mission of the IEA. This paper outlines the key conclusions and policy recommendations to ''keep the lights on'' while reducing CO2 emissions and increasing the efficiency.

  2. An integrated new product development framework - an application on green and low-carbon products

    Science.gov (United States)

    Lin, Chun-Yu; Lee, Amy H. I.; Kang, He-Yau

    2015-03-01

    Companies need to be innovative to survive in today's competitive market; thus, new product development (NPD) has become very important. This research constructs an integrated NPD framework for developing new products. In stage one, customer attributes (CAs) and engineering characteristics (ECs) for developing products are collected, and fuzzy interpretive structural modelling (FISM) is applied to understand the relationships among these critical factors. Based on quality function deployment (QFD), a house of quality is then built, and fuzzy analytic network process (FANP) is adopted to calculate the relative importance of ECs. In stage two, fuzzy failure mode and effects analysis (FFMEA) is applied to understand the potential failures of the ECs and to determine the importance of ECs with respect to risk control. In stage three, a goal programming (GP) model is constructed to consider the outcome from the FANP-QFD, FFMEA and other objectives, in order to select the most important ECs. Due to pollution and global warming, environmental protection has become an important topic. With both governments and consumers developing environmental consciousness, successful green and low-carbon NPD provides an important competitive advantage, enabling the survival or renewal of firms. The proposed framework is implemented in a panel manufacturing firm for designing a green and low-carbon product.

  3. The main problems faced Ukraine in case of low-carbon economy

    Directory of Open Access Journals (Sweden)

    Artemenko L. P.

    2015-05-01

    Full Text Available The article presents main thoughts covering the process of implementation of low-carbon economy principles in Ukraine, presented main problems towards this aim and proposes one of the main steps to be taken on this long-term way. In case of the damaged limit of the natural recourses to be developed in Ukraine nowadays (especially gas, oil, coil, etc., lost of competitive position on international market to be always placed by Ukrainian manufactories, disability to cut the value of carbon gases and then, as a result, disability to ensure Ukrainian obligations by the Kyoto protocol, Ukrainian Government needs to find better solution for solving the problems mentioned above. In this case we should take into account that the main part of these problems appeared in case of the low-carbon economy movement in the world. As we declare our desire to be next to the leaders countries, than we have to find solutions for our problems based on the main international best practices.

  4. Barriers to the Transfer of Low-carbon Electricity Generation Technologies in Four Latin American Countries

    DEFF Research Database (Denmark)

    Desgain, Denis DR; Haselip, James Arthur

    2015-01-01

    This article discusses the conclusions of four national Technology Needs Assessment (TNA) processes in Latin America (2011-2013), as applied to the electricity sector. The primary focus is on the financial and economic barriers identified by countries to the transfer of prioritized low-carbon ene......This article discusses the conclusions of four national Technology Needs Assessment (TNA) processes in Latin America (2011-2013), as applied to the electricity sector. The primary focus is on the financial and economic barriers identified by countries to the transfer of prioritized low......-carbon energy technologies. While many electricity markets in Latin America were liberalized during the 1990s and 2000s, such market-driven reform policies were far from uniform and in reality there exist a diversity of governance frameworks for national electricity markets, exemplified here by Argentina, Cuba...... to the debate about the relationship between financial and economic barriers to technology transfer and electricity market structures, based on a new round of country-driven priorities and analysis, in support of the UNFCCC process on climate change mitigation....

  5. The Influence of Low-carbon Economy on Global Trade Pattern

    Science.gov (United States)

    Xiao-jing, Guo

    Since global warming has seriously endangered the living environment of human being and their health and safety, the development of low-carbon economy has become an irreversible global trend. Under the background of economic globalization, low-carbon economy will surely exert a significant impact on global trade pattern. Countries are paying more and more attention to the green trade. The emission permits trade of carbon between the developed countries and the developing countries has become more mature than ever. The carbon tariff caused by the distribution of the "big cake" will make the low-cost advantage in developing countries cease to exist, which will, in turn, affect the foreign trade, economic development, employment and people's living in developing countries. Therefore, under the background of this trend, we should perfect the relevant laws and regulations on trade and environment as soon as possible, optimize trade structure, promote greatly the development of service trade, transform thoroughly the mode of development in foreign trade, take advantage of the international carbon trading market by increasing the added value of export products resulted from technological innovation to achieve mutual benefit and win-win results and promote common development.

  6. Greenhouse gas emission accounting and management of low-carbon community.

    Science.gov (United States)

    Song, Dan; Su, Meirong; Yang, Jin; Chen, Bin

    2012-01-01

    As the major source of greenhouse gas (GHG) emission, cities have been under tremendous pressure of energy conservation and emission reduction for decades. Community is the main unit of urban housing, public facilities, transportation, and other properties of city's land use. The construction of low-carbon community is an important pathway to realize carbon emission mitigation in the context of rapid urbanization. Therefore, an efficient carbon accounting framework should be proposed for CO₂ emissions mitigation at a subcity level. Based on life-cycle analysis (LCA), a three-tier accounting framework for the carbon emissions of the community is put forward, including emissions from direct fossil fuel combustion, purchased energy (electricity, heat, and water), and supply chain emissions embodied in the consumption of goods. By compiling a detailed CO₂ emission inventory, the magnitude of carbon emissions and the mitigation potential in a typical high-quality community in Beijing are quantified within the accounting framework proposed. Results show that emissions from supply chain emissions embodied in the consumption of goods cannot be ignored. Specific suggestions are also provided for the urban decision makers to achieve the optimal resource allocation and further promotion of low-carbon communities.

  7. Confusion of Low Carbon and Its Interpretation%低碳的疑惑与解读

    Institute of Scientific and Technical Information of China (English)

    王绍增

    2011-01-01

    Low carbon is not a scientific conclusion by fully debated course, nor a strict scientific concept. It has many defects, and has been immorally and irrationally used by capital and scientific corruption. Iflow carbon wants to get out from being exploited, distorted and camouflaged, and seeks good heart of its own, it must do efforts unceasingly. From the long-term benefits, low carbon may serve the humanity as a belief. Landscape architecture is a career to create splendid "sustainable" human living environment splendidly as far as possible.%低碳不是经充分论证的科学结论,也不是严谨的科学概念,它有很多漏洞,并被资本和科技腐败不合理、不道德地利用.低碳若想从被利用、被歪曲、被涂抹的现状中走出来,寻回自己的良善本心,还要不断努力.从长远利益出发,低碳可以作为人类的一种信仰.风景园林是为人类尽量"可持续"精彩地生活创造环境的事业.

  8. Constructing Low Carbon Competition Platform, and Realizing Sustainable Low Carbon Marketing%构建低碳竞争平台,实现可持续的低碳营销

    Institute of Scientific and Technical Information of China (English)

    刘爽

    2011-01-01

    低碳经济时代,企业主动实施低碳营销是企业可以保持长久竞争优势的一个重要筹码。作为一个新生事物,企业界在近两年的实践中暴露出种种误区,威胁着低碳营销的可持续发展。其一:产品没有低碳的效用。其二:低碳营销传播活动与产品(品牌)核心价值偏离。其三:支离破碎的低碳营销不成系统。为了实现低碳营销的可持续发展,企业应当做好产品开发、营销沟通和战略竞争三个关键平台的建设。%In the low-carbon economic time, applying the low carbon marketing is the key point for the enterprises to keep their lasting competency. As a new thing, the enterprises are showing a variety of errors in the nearly two years practice. These errors are menacing the sustainable de velopmerxt of low carbon marketing. The first, the products have no low carbon effect. The second, low carbon marketing activities are deviating from the core values of products. The third, the chaotic low carbon marketing doesn't become system. To fulfill the sustainable development of low carbon marketing, the enterprises should construct the key platforms of Product Development, Marketing Communication and Strategic Competition.

  9. Designing high-temperature steels via surface science and thermodynamics

    Science.gov (United States)

    Gross, Cameron T.; Jiang, Zilin; Mathai, Allan; Chung, Yip-Wah

    2016-06-01

    Electricity in many countries such as the US and China is produced by burning fossil fuels in steam-turbine-driven power plants. The efficiency of these power plants can be improved by increasing the operating temperature of the steam generator. In this work, we adopted a combined surface science and computational thermodynamics approach to the design of high-temperature, corrosion-resistant steels for this application. The result is a low-carbon ferritic steel with nanosized transition metal monocarbide precipitates that are thermally stable, as verified by atom probe tomography. High-temperature Vickers hardness measurements demonstrated that these steels maintain their strength for extended periods at 700 °C. We hypothesize that the improved strength of these steels is derived from the semi-coherent interfaces of these thermally stable, nanosized precipitates exerting drag forces on impinging dislocations, thus maintaining strength at elevated temperatures.

  10. High Strength, Weldable Precipitation Aged Steels

    Science.gov (United States)

    Wilson, Alexander D.

    1987-03-01

    The family of plate steels represented by ASTM Specification A7101 is finding increasing applications. These low carbon, Cu-Ni-Cr-Mo-Cb, copper precipitation hardened steels have been identified by a number of designations over the years. During early development in the late 1960's and first commercial production in 1970, the steels were known as IN-787 (trademark of International Nickel Company).2 ASTM specifications were subsequently developed for structural (A710) and pressure vessel (A736) applications over ten years ago. More recent interest and application of this family of steels by the U.S. Navy has lead to development of a military specification MIL-S-24645 (SH),3 also initially known as "HSLA-80." Significant tonnage is being produced for the U.S. Navy as a replacement for HY80 (MIL-S-16216) in cruiser deck, bulkhead and hull applications.4 In these applications, the enhanced weldability and requirement of no preheat at this high strength and toughness level has been the main motivation for its use. Over the past 15 years, A710 type steels have also been used in a variety of applications, including off-shore platforms, pressure vessels, arctic linepipe valves and off-highway mining truck frames.

  11. Analysis of Low-carbon Tourism Concept and Island Low-carbon Tourism Development Mode%低碳旅游理念及海岛低碳旅游发展模式探析

    Institute of Scientific and Technical Information of China (English)

    安同江; 车慧颖

    2012-01-01

    Low-carbon tourism is a brand-new tourism development mode under the background of tourism industry's response to global climate change and energy crisis and has been gradually accepted and practiced by the public.On the basis of the analysis of concept and characteristics of low-carbon tourism as well as the necessity of the development of low-carbon tourism in Qingdao,the island low-carbon tourism development mode based on governments,tourism destination and tourists is built to aim to push forward further development of low-carbon tourism in island area.%低碳旅游是旅游业在应对全球气候的变化和能源危机的背景下提出的一种新型的旅游发展模式,已逐渐被公众认可和实践。在对低碳旅游概念、特征与海岛进行低碳旅游发展必要性进行分析的基础上,初步构建基于政府、旅游目的地与旅游者为基点的海岛低碳旅游发展模式,旨在引导、推动海岛地区低碳旅游的进一步发展。

  12. 低碳技术及其应用%Low Carbon Technique and Its Application

    Institute of Scientific and Technical Information of China (English)

    林宗虎

    2011-01-01

    Low carbon technique is a general name for different techniques that may reduce carbon dioxide gas discharged in the process of production and livelihood of human being. During the recent one hundred years, with the fast development of economy and increase of people, the use of fossil energy rises rapidly. As a result, on one hand, the fassil energy faces exhaustion; on the other hand, the green house gases, mainly CO2, increase fastly. This may lead to environmental deterioration, global warming, and natural disasters. Therefore, for the sake of environment protection, energy supplement, and the global warming state diminution, the low carbon technique must be applied, the use of fossil fuel must decrease, new energy must be developed, energy saving and CO2 gas discharge decrease must be practiced. In this paper reasons for applying low carbon technique, its classification and its applications in main departments of China are presented.%低碳技术是各种可以使人类生产和生活过程中排出的二氧化碳减少的技术总称.近百年来.随着全球经济的迅速发展和人口增加.化石能源使用量剧增.其后果是一方面使化石能源面临枯竭,另一方面使大气中以CO2为主的温室气体快速增加并导致环境恶化、全球变暖、自然灾害频发.所以必须采用低碳技术.少用化石燃料.节能减排.开发新能源以保护环境、补充能源和改善全球变暖现况.作者论述了低碳技术的采用原因.其分类以及在中国各主要行业中的应用.

  13. Kenya's Climate Change Action Plan. Low Carbon Climate Resilient Development Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, D.; Sawyer, D.; Stiebert, S.; McFatridge, S. [International Institute for Sustainable Development IISD, Winnipeg, Manitoba (Canada); Wuertenberger, L.; Van Tilburg, X.; Hekkenberg, M. [Energy research Centre of the Netherlands ECN, Policy Studies, Amsterdam (Netherlands); Owino, T.; Battye, W. [ClimateCare, Nairobi (Kenya); Mutia, T. [Regional Institute for Social Enterprise Kenya RISE, Nairobi (Kenya); Olum, P. [Climate Change Consultant (Kenya)

    2012-12-15

    Kenya Vision 2030 - the long-term development blueprint for the country - aims to transform Kenya into 'a newly industrialising, middle-income country providing a high quality of life to all its citizens in a clean and secure environment'. A low carbon climate resilient development pathway, as set out in this Climate Change Action Plan, can help meet Vision 2030 goals through actions that address both sustainable development and climate change. This pathway can also help the Government achieve the Millennium Development Goals and other internationally agreed development goals without compromising the environment and its natural resources. As Kenya realizes its development aspirations, there will be gains and risks. A growing population and economy with migration to cities will mean increases in greenhouse gas (GHG) emissions. Resulting environmental and social conditions, including increased competition over resources, could intensify vulnerability to climate risks. Transitioning to a low carbon climate resilient development pathway can address future risks thereby improving Kenya's ability to prosper under a changing climate while reducing the emissions intensity of a growing economy. Moving forward on the 2010 National Climate Change Response Strategy will help Kenya transition to a low carbon climate resilient development pathway that puts people and livelihoods at the forefront. The strategy recognized the importance of climate change and development, and this Climate Change Action Plan is the logical next step. A yearlong multistakeholder participatory process involving the public sector, private sector and civil society resulted in this Action Plan that identifies priority climate change actions for Kenya for the short, medium and long term. The Government of Kenya takes climate change and its impact on development seriously. Climate change is considered a crosscutting issue that will be mainstreamed in the planning process both at the national

  14. Boronized steels with corundum-baddeleyite coatings

    Directory of Open Access Journals (Sweden)

    P. Pokorny

    2016-07-01

    Full Text Available The paper describes preparation and properties of anti-corrosion and anti-abrasive coatings from corundum-baddeleyite ceramics deposited on surface of low-carbon boronized steel S235JRH-1.0038 (EN 10025-1 by plasma spraying method. Adhesive interlayers Fe2B reaches bond strength of up to 20 MPa in the pull-off tests, the ZrO2 - Al2O3 - SiO2 coatings have a value of fracture adhesion of 4 - 6 MPa. Hardness of these ceramic coatings on steel is as high as 1 800 HV100 and its polarization resistance is 1 600 Ω/cm2 to 4 000 Ω/cm2.

  15. Effect of vanadium on structure-property relations of dual phase fe/mn/si/0.1c steels

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Alvin; Koo, J. Y.; Thomas, G.

    1981-11-01

    The role of vanadium on the structure-property relations of dual phase Fe/Mn/Si/0.1C steels has been investigated. After intercritical annealing at 800°C, the steels with and without V were either iced brine quenched or air cooled. The steels were also solution treated at 900°C and subsequently air cooled. Although V modified the resultant microstructure, especially the morphology of carbides, the corresponding mechanical properties are not significantly affected by the modified microstructures. It is concluded that V is not beneficial to such dual phase low carbon steels.

  16. Developing knowledge and strategies for enabling and governing transitions to a low carbon society

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Jørgensen, Ulrik; Lauridsen, Erik Hagelskjær

    Most of the research on low carbon society in Denmark has hitherto focused on developing scenarios and analyzing possible policy instruments, including market mechanisms, costs and impacts in relation to known options and impacts. The Danish Council of Strategic Research funds the four year......, companies, cities, and national and international policy. Theoretically the research alliance builds upon a combination of theories including social practice theory, innovation economy, institutional theory, actor-network theory and governance theory. Through a combination of historical analysis, case...... stakeholders to make continuous adjustments of objectives and means in unavoidably conflict ridden transition processes.  Analyses of how key measures and institutions at different societal levels might contribute to transition processes.  Characterisation of 4-6 typical sustainable transition set...

  17. Experience with LEDS and NAMA Low Carbon Strategies: The Case of Georgia

    Directory of Open Access Journals (Sweden)

    Kakhaberi Mdivani

    2016-06-01

    Full Text Available Low Emission Development Strategies (LEDS and National Appropriate Mitigation Actions (NAMAs have the potential to support developing countries in attaining low carbon goals. In spite of the evident potential, there is a need to learn from practice. This paper explores the case of Georgia. The main research question discussed is: What experience has been gained with the development of LEDS and NAMAs in Georgia? The study reveals that both LEDS and NAMAs are subject to barriers that considerably slow development processes: there is a lack of institutional capacity, little inter-governmental goal alignment and poor coordination of actions, a lack of experienced staff and insufficient, substantial, earmarked funding. Capacity building depends on support from organizations in donor countries. This paper contributes to a growing body of knowledge of the implementation of LEDS and NAMA.

  18. Food systems transition and disruptive low carbon innovation: implications for a food security research agenda.

    Science.gov (United States)

    Tyfield, David

    2011-07-01

    There is a growing consensus that we are facing epochal challenges in global food security. Moreover, these challenges are multiple and complex. Meeting these challenges will involve nothing less than a wholesale socio-technical transition of the agri-food system. Optimizing the efficacy of the contribution of research to such a food security agenda will probably also need new institutional mechanisms and career structures to facilitate new kinds of collaborations and ongoing, longer-term projects. In short, the multiple challenges of food security demand a different political economy of research for effective intervention by science. In making this argument, the paper summarizes the major findings of a recent report regarding the potential impact of so-called 'disruptive' low-carbon innovations in China.

  19. Low carbon scenarios for transport in India: Co-benefits analysis

    DEFF Research Database (Denmark)

    Dhar, Subash; Shukla, P.R.

    2015-01-01

    Dependence on oil for transport is a concern for India's policymakers on three counts – energy security, local environment and climate change. Rapid urbanisation and accompanying motorisation has created some of the most polluting cities in India and rising demand for oil is leading to higher...... imports, besides causing more CO2 emissions. The government of India wants to achieve the climate goals through a sustainability approach that simultaneously addresses other environment and developmental challenges. This paper analyses a sustainable low carbon transport (SLCT) scenario based...... security (cumulative oil demand lower by 3100 Mtoe), improved air quality (PM 2.5 emissions never exceed the existing levels) and the cumulative CO2 emissions are lower by 13 billion t CO2 thereby showing that achieving development objectives with CO2 co-benefits is feasible....

  20. A Group Decision Framework with Intuitionistic Preference Relations and Its Application to Low Carbon Supplier Selection.

    Science.gov (United States)

    Tong, Xiayu; Wang, Zhou-Jing

    2016-09-19

    This article develops a group decision framework with intuitionistic preference relations. An approach is first devised to rectify an inconsistent intuitionistic preference relation to derive an additive consistent one. A new aggregation operator, the so-called induced intuitionistic ordered weighted averaging (IIOWA) operator, is proposed to aggregate individual intuitionistic fuzzy judgments. By using the mean absolute deviation between the original and rectified intuitionistic preference relations as an order inducing variable, the rectified consistent intuitionistic preference relations are aggregated into a collective preference relation. This treatment is presumably able to assign different weights to different decision-makers' judgments based on the quality of their inputs (in terms of consistency of their original judgments). A solution procedure is then developed for tackling group decision problems with intuitionistic preference relations. A low carbon supplier selection case study is developed to illustrate how to apply the proposed decision model in practice.

  1. A Group Decision Framework with Intuitionistic Preference Relations and Its Application to Low Carbon Supplier Selection

    Directory of Open Access Journals (Sweden)

    Xiayu Tong

    2016-09-01

    Full Text Available This article develops a group decision framework with intuitionistic preference relations. An approach is first devised to rectify an inconsistent intuitionistic preference relation to derive an additive consistent one. A new aggregation operator, the so-called induced intuitionistic ordered weighted averaging (IIOWA operator, is proposed to aggregate individual intuitionistic fuzzy judgments. By using the mean absolute deviation between the original and rectified intuitionistic preference relations as an order inducing variable, the rectified consistent intuitionistic preference relations are aggregated into a collective preference relation. This treatment is presumably able to assign different weights to different decision-makers’ judgments based on the quality of their inputs (in terms of consistency of their original judgments. A solution procedure is then developed for tackling group decision problems with intuitionistic preference relations. A low carbon supplier selection case study is developed to illustrate how to apply the proposed decision model in practice.

  2. Development of a Lightweight Low-Carbon Footprint Concrete Containing Recycled Waste Materials

    Directory of Open Access Journals (Sweden)

    S. Talukdar

    2011-01-01

    This study examined the use of waste materials such as crushed glass, ground tire rubber, and recycled aggregate in concrete. Compressive strength and elastic modulus were the primary parameters of interest. Results demonstrated that ground tire rubber introduced significant amounts of air into the mix and adversely affected the strength. The introduction of a defoamer was able to successfully remove part of the excess air from the mix, but the proportional strength improvements were not noted implying that air left in the defoamed mixture had undesirable characteristics. Freeze-thaw tests were next performed to understand the nature of air in the defoamed mixtures, and results demonstrated that this air is not helpful in resisting freeze-thaw resistance either. Overall, while lightweight, low-carbon footprint concrete materials seem possible from recycled materials, significant further optimization remains possible.

  3. Low carbon content NiTi shape memory alloy produced by electron beam melting

    Directory of Open Access Journals (Sweden)

    Otubo Jorge

    2004-01-01

    Full Text Available Earlier works showed that the use of electron beam melting is a viable process to produce NiTi shape memory alloy. In those works a static and a semi-dynamic processes were used producing small shell-shaped and cylindrical ingots respectively. The main characteristics of those samples were low carbon concentration and good composition homogeneity throughout the samples. This paper presents the results of scaling up the ingot size and processing procedure using continuous charge feeding and continuous casting. The composition homogeneity was very good demonstrated by small variation in martensitic transformation temperatures with carbon content around 0.013wt% compared to 0.04 to 0.06wt% of commercial products.

  4. A METHODOLOGY FOR DEVELOPING A ROADMAP TOWARDS LOCAL LOW-CARBON SOCIETY COSIDERING IMPLEMENTATION COST

    Science.gov (United States)

    Gomi, Kei; Kim, Jaegyu; Matsuoka, Yuzuru

    We have developed a methodology for developing roadmaps towards low-carbon society in local government. A quantification tool called "Backcasting Tool" (BCT) was developed. BCT estimates implementation schedule of all policies and actions considering their relationship, financial constraints of the actors, and co-benefit of the policies. The methodology was applied in Shiga prefecture, Japan, and a roadmap which consists of more than 240 policies is estimated considering direct costs paid by public and private sectors. As a result, cumulative implementation cost was 7.3 trillion yen in which public sector bear 17%. Cumulative emission reduction was 101MtCO2, and average emission reduction cost was 73 thousand yen/tCO2.

  5. Formation mechanism of spheroidal carbide in ultra-low carbon ductile cast iron

    Directory of Open Access Journals (Sweden)

    Bin-guo Fu

    2016-09-01

    Full Text Available The formation mechanism of the spheroidal carbide in the ultra-low carbon ductile cast iron fabricated by the metal mold casting technique was systematically investigated. The results demonstrated that the spheroidal carbide belonged to eutectic carbide and crystallized in the isolated eutectic liquid phase area. The formation process of the spheroidal carbide was related to the contact and the intersection between the primary dendrite and the secondary dendrite of austenite. The oxides of magnesium, rare earths and other elements can act as heterogeneous nucleation sites for the spheroidal carbide. It was also found that the amount of the spheroidal carbide would increase with an increase in carbon content. The cooling rate has an important influence on the spheroidal carbide under the same chemical composition condition.

  6. Barriers to the Transfer of Low-carbon Electricity Generation Technologies in Four Latin American Countries

    DEFF Research Database (Denmark)

    Desgain, Denis DR; Haselip, James Arthur

    2015-01-01

    This article discusses the conclusions of four national Technology Needs Assessment (TNA) processes in Latin America (2011-2013), as applied to the electricity sector. The primary focus is on the financial and economic barriers identified by countries to the transfer of prioritized low-carbon ene......This article discusses the conclusions of four national Technology Needs Assessment (TNA) processes in Latin America (2011-2013), as applied to the electricity sector. The primary focus is on the financial and economic barriers identified by countries to the transfer of prioritized low...... to the debate about the relationship between financial and economic barriers to technology transfer and electricity market structures, based on a new round of country-driven priorities and analysis, in support of the UNFCCC process on climate change mitigation....

  7. 低碳旅游之下酒店管理模式%Hotel Management Mode Under Low Carbon Tourism

    Institute of Scientific and Technical Information of China (English)

    帅利平

    2015-01-01

    随着人们环保意识的提升,低碳旅游成为人们关注的热点话题,而景区酒店是旅游经济的重要组成部分,对于低碳旅游发展而言具有重要作用。文章首先对低碳旅游的概念进行分析,对目前低碳旅游下酒店管理方面出现的问题进行总结,对低碳旅游下酒店管理模式提出一些建议。%With the enhancement of peopleˊs awareness of environmental protection,low-carbon tourism has become a hot topic of concern,and the resort hotel is an important part of the tourism economy,in terms of low-carbon tourism development as an important part.Firstly,the concept of low-carbon tourism is analyzed under the current low carbon tourism and hotel management problems are summarized,some suggestions for low-carbon tourism management at the hotel.

  8. Technology Roadmap: Low-Carbon Technology for the Indian Cement Industry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    The Indian cement industry is one of the most efficient in the world. Its efforts to reduce its carbon footprint by adopting the best available technologies and environmental practices are reflected in the achievement of reducing total CO2 emissions to an industrial average of 0.719 tCO2/t cement in 2010 from a substantially higher level of 1.12 tCO2/t cement in 1996. However, because the manufacturing process relies on the burning of limestone, it still produced 137 MtCO2 in 2010 – approximately 7% of India’s total man-made CO2 emissions. Yet opportunity for improvement exists, particularly in relation to five key levers that can contribute to emissions reductions: alternative fuel and raw materials; energy efficiency; clinker substitution; waste heat recovery and newer technologies. This roadmap sets out one pathway by which the Indian cement industry can reach its targets to improve energy efficiency and reduce CO2 emissions by 2050, thereby laying the foundation for low-carbon growth in the years beyond. The Technology Roadmap: Low-Carbon Technology for the Indian Cement Industry builds on the global IEA technology roadmap for the cement sector developed by the IEA and the World Business Council for Sustainable Development’s Cement Sustainability Initiative. It outlines a possible transition path for the Indian cement industry to reduce its direct CO2 emissions intensity to 0.35 tCO2/t cement and support the global goal of halving CO2 emissions by 2050.

  9. Low-Carbon Fuel and Chemical Production by Anaerobic Gas Fermentation.

    Science.gov (United States)

    Daniell, James; Nagaraju, Shilpa; Burton, Freya; Köpke, Michael; Simpson, Séan Dennis

    World energy demand is expected to increase by up to 40% by 2035. Over this period, the global population is also expected to increase by a billion people. A challenge facing the global community is not only to increase the supply of fuel, but also to minimize fossil carbon emissions to safeguard the environment, at the same time as ensuring that food production and supply is not detrimentally impacted. Gas fermentation is a rapidly maturing technology which allows low carbon fuel and commodity chemical synthesis. Unlike traditional biofuel technologies, gas fermentation avoids the use of sugars, relying instead on gas streams rich in carbon monoxide and/or hydrogen and carbon dioxide as sources of carbon and energy for product synthesis by specialized bacteria collectively known as acetogens. Thus, gas fermentation enables access to a diverse array of novel, large volume, and globally available feedstocks including industrial waste gases and syngas produced, for example, via the gasification of municipal waste and biomass. Through the efforts of academic labs and early stage ventures, process scale-up challenges have been surmounted through the development of specialized bioreactors. Furthermore, tools for the genetic improvement of the acetogenic bacteria have been reported, paving the way for the production of a spectrum of ever-more valuable products via this process. As a result of these developments, interest in gas fermentation among both researchers and legislators has grown significantly in the past 5 years to the point that this approach is now considered amongst the mainstream of emerging technology solutions for near-term low-carbon fuel and chemical synthesis.

  10. Implementation of Low Carbon Construction Activities in Order to Optimize Water Consumption on the Construction Site

    Directory of Open Access Journals (Sweden)

    Reza Esmaeilifar

    2014-06-01

    Full Text Available The number of law carbon construction project had increased tremendously across Malaysia over the recent years. In fact, there is no doubt on the necessity of development law carbon construction and benefits that have for the society, specifically for the construction companies. In order to make significant inroads into the low carbon construction practices, the industry needs to improve its energy usage and natural resources consumed in all its construction site activities. This study attempts to evaluate the sources of CO2 emission regarding water usage during construction project; secondly, to identify effective optimization method with regard to water usage in construction activities; and finally, to provide a plan of actions to minimize CO2 emissions during construction activities. SPSS version 20 was used to analyse the collected data. 385 questionnaires were distributed to the construction companies in Malaysia. The findings revealed that, despite the importance of low carbon construction, not many companies are serious enough to cut down their natural resource consumption. The particular phenomena, myriad of contractors and construction firms in Malaysia have not yet paid attention binding themselves to carbon construction and green building's constitution in general by contrast to common construction activity. The location of the site for water is the main way for the law carbon construction and has been highlighted as the main reason of ignorance of the current situation within the construction sector. Indeed, introducing optimization methods is vital for contractors and supervisors of the sites to be motivated regarding inequality on usage of water during construction project, which lead to carbon dioxide creation. In addition to optimization water consumption, monitoring the usage of water during construction activity can play as a main role.

  11. Trends and Issues in California's Low Carbon Fuel Standard - Learning from Response to Existing Climate Policy

    Science.gov (United States)

    Witcover, J.

    2015-12-01

    Debate over lower greenhouse gas (GHG) emissions from transportation has included heated discussion about appropriate policies and their cost and feasibility. One prominent policy mechanism, a carbon intensity standard, rates transport fuels based on analysis of lifecycle GHG emissions, and targets lower fuel pool carbon intensity through a market mechanism that uses a system of tradable, bankable credits and deficits. California instituted such a policy -- the Low Carbon Fuel Standard (LCFS) - in 2010, which targets a 10% carbon intensity (CI) reduction by 2020. The program rolled out amid concerns over slow development of new fuels expected to be very low carbon (such as cellulosic) and has faced court challenges that added considerable policy uncertainty. Since the program's start, state transport energy mix has shifted modestly but noticeably. Looking ahead, emerging issues for the program include amendments and re-adoption in response to a court ruling, potential interaction with California's multi-sector cap on carbon emissions (which started covering transport fuels in 2015), and impacts from similar CI standards in other jurisdictions. This study provides an analysis of fuel mix changes since the LCFS was implemented in 2011, and a discussion of emerging issues focusing on policy interaction. Descriptive statistics on alternative fuel use, available fuel pathways, and CI ratings are presented based on data from the California Air Resources Board (which runs the program). They document a shift towards more alternative fuels in a more diverse mix, with lower average CI ratings for most alternative fuel types. Financial incentives for various fuels are compared under the LCFS and the US federal Renewable Fuel Standard; disincentives from conceptually different carbon pricing schemes under the LCFS and the Cap-and-Trade are also outlined. The results provide important information on response to an existing market-based policy mechanism for addressing GHG

  12. Thermomechanically-controlled Processing for Producing Ship-building Steels

    Directory of Open Access Journals (Sweden)

    B. Basu

    2005-01-01

    Full Text Available The thermomechanically-controlled processing of a newly developed high-strength lowalloy steel has been designed in such a way that the problems, normally faced in producing thequench and tempered steels, have been mitigated and the final product (steel plates are available in as rolled condition rather than quench and tempered steels.A low-carbon, low-alloy steel having nickel, chromium, copper, niobium, boron, has been designed for ease of welding, improved weldability over the conventional steels, and responsiveto the thermomechanically-controlled processing. A number of laboratory-scale batches of the alloy were made with different combinations of thermomechanically-controlled processingparameters. The different thermomechanically-controlled processing parameters studied include (i slab-reheating temperature,~ (ii. def.orm ation above recrvstallisation temperature, (iiideformation below recrystallisation temperature, and (iv finish-rolling temperature. The thermomechanically-processed steel plates, under certain combinations of  thermomechanically-controlled ~rocessi-ne.o arameters. showed excellent combination of imvact and tensile n.r on. erties. In this paper, the microstructure-property correlation has been made to throw light on the type of microstructure required to obtain such superior package of mechanical properties. Further, the optimised laboratory-scale thermomechanically-controlled processing parameters, which were used to process newer hatches of the steel made through industrial route, have delivered encouraging results.

  13. Microstructure and mechanical behavior of neutron irradiated ultrafine grained ferritic steel

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad Alsabbagh; Apu Sarkar; Brandon Miller; Jatuporn Burns; Leah Squires; Douglas Porter; James I. Cole; K. L. Murty

    2014-10-01

    Neutron irradiation effects on ultra-fine grain (UFG) low carbon steel prepared by equal channel angular pressing (ECAP) has been examined. Counterpart samples with conventional grain (CG) sizes have been irradiated alongside with the UFG ones for comparison. Samples were irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) to 1.24 dpa. Atom probe tomography revealed manganese, silicon-enriched clusters in both ECAP and CG steel after neutron irradiation. X-ray quantitative analysis showed that dislocation density in CG increased after irradiation. However, no significant change was observed in UFG steel revealing better radiation tolerance.

  14. A Probe into Process for Maximization of Low-carbon Oleifns via Co-processing of Methanol and Heavy Oil

    Institute of Scientific and Technical Information of China (English)

    Song Baomei

    2013-01-01

    From the viewpoint of process speciifcs and thermodynamics, this article has put forward a route for maximiza-tion of low-carbon oleifns via co-processing of methanol and heavy oil. Catalytic cracking experiments on co-processing of methanol and heavy oil at different ratios in a ifxed lfuidized bed reactor had been conducted. Test results have revealed that when 12.5%of methanol was blended to the heavy oil a good products distribution and relatively higher yield of low-carbon oleifns could be obtained. The overall yield of low-carbon oleifns could reach 50.16%, with the yield of ethylene, propylene and butylene equating to 5.47%, 28.93%and 15.76%, respectively.

  15. The Relationship between Low-carbon Agriculture and Agricultural Science and Technology Based on Gray Relational Theory

    Institute of Scientific and Technical Information of China (English)

    TAO Ai-xiang

    2012-01-01

    The agricultural energy consumption per unit of GDP is selected as an indicator for measuring the development level of low-carbon agriculture. Using gray relational theory, I analyze the relationship between development level of agricultural science and technology and development level of low-carbon agriculture in China. The results show that the correlation between the two is prominent; the number of agricultural science and technology talents, the number of agricultural science and technology patents, and the number of agricultural science and technology input are three major factors influencing the development of low-carbon agriculture. On this basis, I propose to take further effective measures, and put forth corresponding recommendations, in order to improve the level of agricultural science and technology.

  16. The Humanity Marches into the Low-Carbon Time%人类步入低碳时代

    Institute of Scientific and Technical Information of China (English)

    王国莲

    2011-01-01

    The low-carbon time's arrival, is international big background making to cause to so, particularly the energy crisis, the climate crisis and financial crisis's superimposed effect, its bright attribute is the iow-carbon which fierce disputes' climate politics,engulfs the entire world economical, the vigorous development low-carbon science and technology, the aware showing low-carbon culture, this indicates the human culture jump.%低碳时代的到来,是国际大背景使然,尤其是能源危机、气候危机和金融危机的叠加效应,其鲜明表征是激烈交锋的气候政治、席卷全球的低/碳经济、蓬勃发展的低碳科技、自觉彰显的低/碳文化,这预示着人类文明的跃迁.

  17. Evaluating Ecological and Economic Benefits of a Low-Carbon Industrial Park Based on Millennium Ecosystem Assessment Framework

    Directory of Open Access Journals (Sweden)

    Bin Chen

    2012-01-01

    Full Text Available The Millennium Ecosystem Assessment (MA framework was modified with a special focus on ecosystem service values. A case study of a typical low-carbon industrial park in Beijing was conducted to assess the ecological and economic benefits. The total economic value of this industrial park per year is estimated to be 1.37×108 RMB yuan, where the accommodating and social cultural services are the largest two contributors. Due to the construction of small grasslands or green roofs, considerable environmental regulation services are also provided by the park. However, compared with an ecoindustrial park, carbon mitigation is the most prominent service for the low-carbon industrial park. It can be concluded that low-carbon industrial park construction is an efficacious way to achieve coordinated development of society, economy, and environment, and a promising approach to achieving energy saving and carbon reduction.

  18. The Effect of Graphite Particle Size on Properties of Low Carbon MgO-C Composite Materials

    Institute of Scientific and Technical Information of China (English)

    LI Lin; HONG Yanruo; SUN Jialin; OUYANG Junhua; HE Zhiyong; YU Li

    2004-01-01

    The effects of graphite granularity on the properties of low carbon MgO-C based materials have been investigated in the work. Large crystal fused magnesia, natural flake graphite with different particle sizes and anti-oxidant were adopted as raw material for preparation of specimens.However, the results show that the physical properties,oxidation resistance and thermal shock resistance of low carbon MgO- C materials with content of 4.0 wt % graphite are improved obviously through the use of special and suitable size graphite. The excellent performance achieved was considered as a result of microstructure modification of MgO-C materials. Therefore, it is suggested that both fine and micro grade natural flake graphite used for production of low carbon MgO- C bricks.

  19. The Strategy for the Development of Low-carbon Animal Husbandry in Taiwan and the Lessons Drawn from It

    Institute of Scientific and Technical Information of China (English)

    Tian; CHEN; Haifeng; XIAO

    2014-01-01

    In this paper,we analyze the strategies for the development of low-carbon animal husbandry in Taiwan which mainly focuses on strengthening the livestock farm carbon reduction,promoting the livestock breeding energy conservation and emission reduction technology,and develop the environmental protection laws related to animal husbandry to combat animal husbandry pollution. Learning from the strategies and legislative management experience for the development of low-carbon animal husbandry in Taiwan,we set forth the following recommendations for improving the development of low-carbon animal husbandry in mainland China: increasing the financial investment in environmental protection; strengthening the scientific research of cleaner production; promoting sound pollution control legislation; moderately restricting the scale of livestock and poultry farm.

  20. Advances on reseach of low-carbon agriculture%低碳农业研究进展

    Institute of Scientific and Technical Information of China (English)

    魏斌; 张灵菲; 葛庆征; 张卫国; 江小雷

    2012-01-01

    Low carbon economy is becoming a global focus problem since World Climate Conference in Copenhagen in December 2009.Low-carbon economy is an economic model which is based on low energy consumption,low emissions and low pollution.Low-carbon agriculture is a form of low carbon economy in agriculture,which is not only improving the agro-ecosystem adaptation to climate change,but also reducing the influence of agricultural development on the ecosystem carbon cycle,and maintaining the carbon balance of the biosphere.Reviewing rencent literature on the subject,the concept and characteristic of low-carbon agriculture,the status of low-carbon agricultural development,the carbon situation of grassland ecosystems,the problems and strategies in low-carbon agricultural development are discussed.This review will be a valuable reference source for research of low carbon agriculture and grassland ecosystem and will promote carbon sequestration and mitigation research in China.%低碳农业是低碳经济在农业发展中的实现形式,发展低碳农业除了秉承低碳经济的内涵之外,关键在于提高农业生态系统对气候变化的适应性并降低农业发展对生态系统碳循环的影响,维持生物圈的碳平衡。本研究在阅读大量文献的基础上,对低碳农业的概念、低碳农业的特点、低碳农业的发展现状、草地生态系统中的碳循环及低碳农业发展存在的问题及对策进行了综述,以期为我国低碳农业及草业的发展提供参考。

  1. What changes, if any, would increased levels of low-carbon decentralised energy have on the built environment?

    Energy Technology Data Exchange (ETDEWEB)

    Keirstead, James [Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom)

    2008-12-15

    Low-carbon decentralised energy technologies (DETs) have become increasingly popular in recent UK energy policy debates. Many of the technologies involved are well established, but it is only with their increased technical maturity and the imperatives of climate change, energy security and fuel poverty that DETs have been realistically suggested as an integral part of our future built environment. This review will consider the possible physical and behavioural impacts of increased levels of low-carbon decentralised energy, presenting both recent research in this field and an analysis of policy trends and future scenarios. (author)

  2. The Low Carbonization Usage Technologies of Coal%煤碳的低碳化利用技术

    Institute of Scientific and Technical Information of China (English)

    姚伟; 任世营

    2012-01-01

    The low carbonization technologies such as efficient combustion, advanced coal chemical indus- try and carbon capture and storage are introduced. These provide the ways to develop the low carboniza-tion usage technologies of high- carbon energy and realize the low-carbon economy.%介绍了煤炭高效燃烧、新型煤化工及碳的捕捉和封存等相关的低碳化技术,为发展高碳能源低碳化利用技术、实现低碳经济提供了方向。

  3. Japanese challenge to create a low carbon society - 'Clean coal technologies, now and future'

    Energy Technology Data Exchange (ETDEWEB)

    Nakagaki, Yoshihiko; Yoshida, Minoru; Noguchi, Yoshikazu

    2010-09-15

    Under the increase of world energy demand, especially in major developing countries, energy demand will not be satisfied without coal. It is true that 30% of carbon dioxide emission is from coal-fired power stations, and there is no other effective solution than abating these emissions. The key is Clean Coal Technologies (CCT), to make power stations to low carbon. It is necessary to develop and transfer these CCTs together with developed and developing countries. Japan, who has excellent CCTs, should play an important role to develop higher innovative technologies and is challenging to make a low carbon society in the world.

  4. Low Carbon Supply Chain’s Performance Evaluation Based on Entropy Method and Fuzzy Comprehensive Evaluation Method

    Directory of Open Access Journals (Sweden)

    Xu Xu

    2013-06-01

    Full Text Available This study constructed a performance evaluation index system of low carbon supply chain from the economic, resources and environment. This index system highlights the environmental value orientation and green culture technology evaluation. On this basis, uses entropy value method to definite the index system of index weigh and uses the fuzzy comprehensive evaluation method to establish the evaluation model. It overcomes the respective faults of the entropy value method and fuzzy comprehensive evaluation method and makes low carbon supply chain performance evaluation more scientific and accurate. Finally, the model was verified analysis.

  5. Study on Evaluation of Green Low -carbon Port%绿色低碳港口评价研究

    Institute of Scientific and Technical Information of China (English)

    瞿群臻; 刘帅

    2013-01-01

    港口在发展的同时也造成了一定的负面影响,绿色低碳港口是顺应绿色、低碳、可持续发展趋势的未来港口发展的主要模式。绿色低碳港口评价指标体系的构建是绿色低碳港口建设的前提与重要保障。文章在分析绿色低碳港口内涵的基础上,阐述了构建绿色低碳港口评价指标体系的基本方法,并从经济、社会、环境、生态、资源5个角度出发构建出包含港口绿色GDP贡献率、港区人口密度、港区废水与废气排放达标率、港区生态多样性、单位吞吐量综合能源消耗量等25个具体评价指标的绿色低碳港口评价指标体系。同时运用层次分析法和模糊数学法构建出绿色低碳港口模糊综合评价模型,并结合S港口进行案例分析。此外,结合评价指标体系提出了推广船用岸电等绿色低碳新技术,设立港区环保专项基金,开发利用绿色低碳新能源等绿色低碳港口建设方面的对策建议。%Ports have caused some negative impact on the great development . Green low -carbon port confirms the trend of green , low -carbon and sustainable development . And it will be the main mode of the future port development . The construction of evaluation in-dex system of green low -carbon port is the prerequisite and important guarantee for the construction of green low -carbon port . Article based on the analysis of the connotation of green low -carbon port , this paper expounds the basic methods of constructing evaluation index system of green low -carbon port , constructs the evaluation index system of green low -carbon port which includes Green GDP contribution rate of port , population density , waste water and emissions compliance rate , ecological diversity and comprehensive energy consumption per unit throughput , etc . 25 specific evaluation indicators from five angles of economic , social , environment , ecology , resource . At the same time , this paper

  6. Hybrid Geo-Energy Systems for Energy Storage and Dispatchable Renewable and Low-Carbon Electricity

    Science.gov (United States)

    Buscheck, Thomas; Bielicki, Jeffrey; Ogland-Hand, Jonathan; Hao, Yue; Sun, Yunwei; Randolph, Jimmy; Saar, Martin

    2015-04-01

    conditions enable efficient fluid recirculation, heat extraction, power conversion, and add operational flexibility to dispatch electricity. Overall, the system can (a) levelize concentrating solar power, (b) mitigate variability of wind and solar power, (c) reduce water and carbon intensity of energy systems, (d) avoid wasting or curtailing high-capital cost, low-carbon energy resources and (e) allow low-carbon, base-load power to operate at full capacity. This work was performed under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, and has been funded by the U.S. National Science Foundation Sustainable Energy Pathways Program (1230691) and the U.S. Department of Energy Geothermal Technologies Office (DE-FOA-0000336).

  7. Low-carbon energy policy and ambient air pollution in Shanghai, China. A health-based economic assessment

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Changhong; Wang, Bingyan [Shanghai Academy of Environmental Sciences, Shanghai 200233 (China); Chen, Bingheng; Kan, Haidong [Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032 (China); Huang, Cheng; Zhao, Jing; Dai, Yi [East China University of Science and Technology, Shanghai 200237 (China)

    2007-02-01

    Energy and related health issues are of growing concern worldwide today. To investigate the potential public health and economic impact of ambient air pollution under various low-carbon energy scenarios in Shanghai, we estimated the exposure level of Shanghai residents to air pollution under various planned scenarios, and assessed the public health impact using concentration-response functions derived from available epidemiologic studies. We then estimated the corresponding economic values of the health effects based on unit values for each health outcome. Our results show that ambient air pollution in relation to low-carbon energy scenarios could have a significant impact on the future health status of Shanghai residents, both in physical and monetary terms. Compared with the base case scenario, implementation of various low-carbon energy scenarios could prevent 2804-8249 and 9870-23,100 PM{sub 10}-related avoidable deaths (mid-value) in 2010 and 2020, respectively. It could also decrease incidence of several relevant diseases. The corresponding economic benefits could reach 507.31-1492.33 and 2642.45-6192.11 million U.S. dollars (mid-value) in 2010 and 2020, respectively. These findings illustrate that a low-carbon energy policy will not only decrease the emission of greenhouse gases, but also play an active role in the reduction of air pollutant emissions, improvement of air quality, and promotion of public health. Our estimates can provide useful information to local decision-makers for further cost-benefit analysis. (author)

  8. Low-carbon energy policy and ambient air pollution in Shanghai, China: A health-based economic assessment

    Energy Technology Data Exchange (ETDEWEB)

    Chen Changhong [Shanghai Academy of Environmental Sciences, Shanghai 200233 (China); Chen Bingheng [Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032 (China); Wang Bingyan [Shanghai Academy of Environmental Sciences, Shanghai 200233 (China); Huang Cheng [East China University of Science and Technology, Shanghai 200237 (China); Zhao Jing [East China University of Science and Technology, Shanghai 200237 (China); Dai Yi [East China University of Science and Technology, Shanghai 200237 (China); Kan Haidong [Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032 (China)]. E-mail: haidongkan@gmail.com

    2007-02-01

    Energy and related health issues are of growing concern worldwide today. To investigate the potential public health and economic impact of ambient air pollution under various low-carbon energy scenarios in Shanghai, we estimated the exposure level of Shanghai residents to air pollution under various planned scenarios, and assessed the public health impact using concentration-response functions derived from available epidemiologic studies. We then estimated the corresponding economic values of the health effects based on unit values for each health outcome. Our results show that ambient air pollution in relation to low-carbon energy scenarios could have a significant impact on the future health status of Shanghai residents, both in physical and monetary terms. Compared with the base case scenario, implementation of various low-carbon energy scenarios could prevent 2804-8249 and 9870-23,100 PM{sub 10}-related avoidable deaths (mid-value) in 2010 and 2020, respectively. It could also decrease incidence of several relevant diseases. The corresponding economic benefits could reach 507.31-1492.33 and 2642.45-6192.11 million U.S. dollars (mid-value) in 2010 and 2020, respectively. These findings illustrate that a low-carbon energy policy will not only decrease the emission of greenhouse gases, but also play an active role in the reduction of air pollutant emissions, improvement of air quality, and promotion of public health. Our estimates can provide useful information to local decision-makers for further cost-benefit analysis.

  9. Principles for Low-Carbon Landscape Architecture and Design%低碳园林及其设计原则

    Institute of Scientific and Technical Information of China (English)

    唐志军; 王凌云

    2011-01-01

    Low-carbon is a new idea of saving energy and environmental protection.It is developed against the background of globe serious climate change and gradually shortage of traditional fossil fuels.In light of the increasingly serious pollution and bad urban environment climate,low-carbon landscape is undoubtedly one of the effective ways to relieve the climate change.This paper analyzed the low-carbon concept and background concerned,and discussed the principles of low-carbon landscape design.%低碳,是在全球气候变化逐渐尖锐,传统化石燃料日渐贫乏的时代背景下提出的一种新型、节能环保的理念。面对污染日益严重、气候日渐恶劣的城市环境,低碳园林无疑是缓解尖锐气候的有效途径之一。本文,通过对低碳理念及其产生背景的剖析,提出了低碳园林的设计原则。

  10. “Decoupling” Indicators for Evaluation of Urban Low-Carbon Economy Development: a Case Study of Shanghai

    Science.gov (United States)

    Zhao, Jing; Xu, Ting; Yin, Daqiang; GU, Weihua; Huang, Qing

    2017-01-01

    Environment are closely related to energy and they are two of the most important issues this century. So the development of a low-carbon economy and the construction of environment friendly society are the only way for the further development of China its own. In this study, “decoupling” indicators for evaluation of a low-carbon economy development are proposed. “Decoupling” indicators of energy consumption and economic growth were selected to reflect the response relationship between economic growth and the changes of resources, including weak, strong and expansive/recessive degree of decoupling. Similarly, “decoupling” indicators of carbon dioxide emissions and economic growth were chosen to reflect the response relationship between economic growth and the changes of environment. Shanghai, in the Eastern China, was selected as a special case. The results showed a change from expansive negative coupling to week decoupling regarding both of energy consumption and carbon emissions in Shanghai during the period 1991-2013, indicating that we have achieved some significant outcome in the process of the low-carbon economy development in Shanghai. However, in view of the possibility of expansive negative coupling, we should continue to make efforts for the development of the low-carbon economy.

  11. Transportation Energy Futures Series: Alternative Fuel Infrastructure Expansion: Costs, Resources, Production Capacity, and Retail Availability for Low-Carbon Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Melaina, M. W.; Heath, G.; Sandor, D.; Steward, D.; Vimmerstedt, L.; Warner, E.; Webster, K. W.

    2013-04-01

    Achieving the Department of Energy target of an 80% reduction in greenhouse gas emissions by 2050 depends on transportation-related strategies combining technology innovation, market adoption, and changes in consumer behavior. This study examines expanding low-carbon transportation fuel infrastructure to achieve deep GHG emissions reductions, with an emphasis on fuel production facilities and retail components serving light-duty vehicles. Three distinct low-carbon fuel supply scenarios are examined: Portfolio: Successful deployment of a range of advanced vehicle and fuel technologies; Combustion: Market dominance by hybridized internal combustion engine vehicles fueled by advanced biofuels and natural gas; Electrification: Market dominance by electric drive vehicles in the LDV sector, including battery electric, plug-in hybrid, and fuel cell vehicles, that are fueled by low-carbon electricity and hydrogen. A range of possible low-carbon fuel demand outcomes are explored in terms of the scale and scope of infrastructure expansion requirements and evaluated based on fuel costs, energy resource utilization, fuel production infrastructure expansion, and retail infrastructure expansion for LDVs. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored transportation-related strategies for abating GHGs and reducing petroleum dependence.

  12. Low-carbon energy policy and ambient air pollution in Shanghai, China: a health-based economic assessment.

    Science.gov (United States)

    Chen, Changhong; Chen, Bingheng; Wang, Bingyan; Huang, Cheng; Zhao, Jing; Dai, Yi; Kan, Haidong

    2007-02-01

    Energy and related health issues are of growing concern worldwide today. To investigate the potential public health and economic impact of ambient air pollution under various low-carbon energy scenarios in Shanghai, we estimated the exposure level of Shanghai residents to air pollution under various planned scenarios, and assessed the public health impact using concentration-response functions derived from available epidemiologic studies. We then estimated the corresponding economic values of the health effects based on unit values for each health outcome. Our results show that ambient air pollution in relation to low-carbon energy scenarios could have a significant impact on the future health status of Shanghai residents, both in physical and monetary terms. Compared with the base case scenario, implementation of various low-carbon energy scenarios could prevent 2804-8249 and 9870-23,100 PM10-related avoidable deaths (mid-value) in 2010 and 2020, respectively. It could also decrease incidence of several relevant diseases. The corresponding economic benefits could reach 507.31-1492.33 and 2642.45-6192.11 million U.S. dollars (mid-value) in 2010 and 2020, respectively. These findings illustrate that a low-carbon energy policy will not only decrease the emission of greenhouse gases, but also play an active role in the reduction of air pollutant emissions, improvement of air quality, and promotion of public health. Our estimates can provide useful information to local decision-makers for further cost-benefit analysis.

  13. Co-Generation and Renewables: Solutions for a Low-Carbon Energy Future

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Co-generation and renewables: solutions for a low-carbon energy future shows that powerful synergies exist when co-generation and renewables work together. The report documents, for the first time, some of the little-known complementary aspects of the two technologies. It also re-emphasises the stand-alone benefits of each technology. Thus, decision makers can use the report as a 'one-stop shop' when they need credible information on co-generation, renewables and the possible synergies between the two. It also provides answers to policy makers' questions about the potential energy and environmental benefits of an increased policy commitment to both co-generation and renewables. Secure, reliable, affordable and clean energy supplies are fundamental to economic and social stability and development. Energy and environmental decision-makers are faced with major challenges that require action now in order to ensure a more sustainable future. More efficient use of, and cleaner primary energy sources can help to achieve this goal. Co-generation -- also known as combined heat and power (CHP) -- represents a proven, cost-effective and energy-efficient solution for delivering electricity and heat. Renewable sources provide clean and secure fuels for producing electricity and heat.

  14. Incorporating land-use requirements and environmental constraints in low-carbon electricity planning for California.

    Science.gov (United States)

    Wu, Grace C; Torn, Margaret S; Williams, James H

    2015-02-17

    The land-use implications of deep decarbonization of the electricity sector (e.g., 80% below 1990 emissions) have not been well-characterized quantitatively or spatially. We assessed the operational-phase land-use requirements of different low-carbon scenarios for California in 2050 and found that most scenarios have comparable direct land footprints. While the per MWh footprint of renewable energy (RE) generation is initially higher, that of fossil and nuclear generation increases over time with continued fuel use. We built a spatially explicit model to understand the interactions between resource quality and environmental constraints in a high RE scenario (>70% of total generation). We found that there is sufficient land within California to meet the solar and geothermal targets, but areas with the highest quality wind and solar resources also tend to be those with high conservation value. Development of some land with lower conservation value results in lower average capacity factors, but also provides opportunity for colocation of different generation technologies, which could significantly improve land-use efficiency and reduce permitting, leasing, and transmission infrastructure costs. Basing siting decisions on environmentally-constrained long-term RE build-out requirements produces significantly different results, including better conservation outcomes, than implied by the current piecemeal approach to planning.

  15. Low-carbon Economic Review%低碳经济综述

    Institute of Scientific and Technical Information of China (English)

    张敏

    2012-01-01

      随着气候变化影响的日益显著,全球变暖问题越来越多的受到国际关注,由于全球对化石燃料的过度依赖,工业和人们生活中的废气排放日益增加,由此导致的空气污染和温室效应,使得碳排放已经成为人类生存环境的最大威胁。基于全球变暖和环境的日益恶化对人类生存和发展的严重挑战,低碳经济模式将成为未来经济发展的必然选择。%  Along with the effects of climate change becomes remarkable increasingly,the problem of global warming aroused more and more international concern. The excessive dependence on fossil fuel and the exhaust emission caused by industry and people’s life increased,which lead to air pollution and greenhouse effect,so carbon emissions has become the biggest threat to human survival environment . As the serious challenge of global warming and the environment of increasing deterioration for human survival and development,low carbon economic model will become the inevitable choice of economic development in future.

  16. Safety and effective developing nuclear power to realize green and low-carbon development

    Directory of Open Access Journals (Sweden)

    Qi-Zhen Ye

    2016-03-01

    Full Text Available This paper analyzes the role of nuclear power of China's energy structure and industry system. Comparing with other renewable energy the nuclear power chain has very low greenhouse gas emission, so it will play more important role in China's low-carbon economy. The paper also discussed the necessity of nuclear power development to achieve emission reduction, energy structure adjustment, nuclear power safety, environmental protection, enhancement of nuclear power technology, nuclear waste treatment, and disposal, as well as nuclear power plant decommissioning. Based on the safety record and situation of the existing power plants in China, the current status of the development of world nuclear power technology, and the features of the independently designed advanced power plants in China, this paper aims to demonstrate the safety of nuclear power. A nuclear power plant will not cause harm either to the environment and nor to the public according to the real data of radioactivity release, which are obtained from an operational nuclear plant. The development of nuclear power technology can enhance the safety of nuclear power. Further, this paper discusses issues related to the nuclear fuel cycle, the treatment, and disposal strategies of nuclear waste, and the decommissioning of a nuclear power plant, all of which are issues of public concern.

  17. Community action for sustainable housing: Building a low-carbon future

    Energy Technology Data Exchange (ETDEWEB)

    Seyfang, Gill, E-mail: g.seyfang@uea.ac.u [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom)

    2010-12-15

    This paper presents a new analytical framework of 'grassroots innovations' which views community-led initiatives for sustainable development as strategic green niches with the potential for wider transformation of mainstream society. This framework is applied to a low-carbon, low-impact, community-based sustainable housing initiative in the USA that pioneers straw bale housing techniques within a strong community-building ethos. The project is evaluated according to New Economics criteria of sustainable consumption, and is found to be successful at localising the construction supply chain, reducing ecological footprints, community-building, enabling collective action and building new institutions and systems of provision around housebuilding. However, viewing it as a strategic niche with aim to influence wider society, it is clear that it faces significant challenges in diffusing its ideas and practices beyond the niche. Its model is not necessarily suitable for scaling up or widespread replication; however, the scope for niche lessons to be adopted by mainstream builders is greater, given a supportive policy environment. Recognising the innovative nature of green niches at the policy level could lead to new approaches to governance of bottom-up community action for sustainable development.

  18. Community action for sustainable housing. Building a low-carbon future

    Energy Technology Data Exchange (ETDEWEB)

    Seyfang, Gill [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom)

    2010-12-15

    This paper presents a new analytical framework of 'grassroots innovations' which views community-led initiatives for sustainable development as strategic green niches with the potential for wider transformation of mainstream society. This framework is applied to a low-carbon, low-impact, community-based sustainable housing initiative in the USA that pioneers straw bale housing techniques within a strong community-building ethos. The project is evaluated according to New Economics criteria of sustainable consumption, and is found to be successful at localising the construction supply chain, reducing ecological footprints, community-building, enabling collective action and building new institutions and systems of provision around housebuilding. However, viewing it as a strategic niche with aim to influence wider society, it is clear that it faces significant challenges in diffusing its ideas and practices beyond the niche. Its model is not necessarily suitable for scaling up or widespread replication; however, the scope for niche lessons to be adopted by mainstream builders is greater, given a supportive policy environment. Recognising the innovative nature of green niches at the policy level could lead to new approaches to governance of bottom-up community action for sustainable development. (author)

  19. Production of Low-carbon Light Olefins from Catalytic Cracking of Crude Bio-oil

    Institute of Scientific and Technical Information of China (English)

    Yan-ni Yuan; Tie-jun Wang; Quan-xin Li

    2013-01-01

    Low-carbon light olefins are the basic feedstocks for the petrochemical industry.Catalytic cracking of crude bio-oil and its model compounds (including methanol,ethanol,acetic acid,acetone,and phenol) to light olefins were performed by using the La/HZSM-5 catalyst.The highest olefins yield from crude bio-oil reached 0.19 kg/(kg crude bio-oil).The reaction conditions including temperature,weight hourly space velocity,and addition of La into the HZSM-5 zeolite can be used to control both olefins yield and selectivity.Moderate adjusting the acidity with a suitable ratio between the strong acid and weak acid sites through adding La to the zeolite effectively enhanced the olefins selectivity and improved the catalyst stability.The production of light olefins from crude bio-oil is closely associated with the chemical composition and hydrogen to carbon effective ratios of feedstock.The comparison between the catalytic cracking and pyrolysis of bio-oil was studied.The mechanism of the bio-oil conversion to light olefins was also discussed.

  20. Multi-Objective Low-Carbon Economic Dispatch Considering Demand Response with Wind Power Integrated Systems

    Directory of Open Access Journals (Sweden)

    Liu Wenjuan

    2017-01-01

    Full Text Available The generation cost, carbon emissions and customers’ satisfaction are considered in this paper. On the basis of this, the multi-objective and low-carbon economic dispatch model with wind farm, this considers demand response, is established. The model user stochastic programming theory to describe the uncertainty of the wind power and converts it into an equivalent deterministic model by using distribution function of wind power output, optimizes demand side resources to adjust the next day load curve and to improve load rate and absorptive capacity of wind power, introduce customers’ satisfaction to ensure that the scheduling scheme satisfies customer and integrate the resources of source and load to unify coordination wind farm access to network and to meet the requirements of energy saving and emission reduction. The search process of artificial fish school algorithm introducing Tabu search and more targeted search mechanism, an multi-objective improved artificial fish school algorithm is proposed to solve this model. Using the technique for order preference by similarity to ideal solution (TOPSIS to sort the Pareto frontier, the optimal scheduling scheme is determined. Simulation results verify the rationality and validity of the proposed model and algorithm.