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Sample records for 5l x70 steel

  1. Apportion of Charpy energy in API 5L grade X70 pipeline steel

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    Hashemi, Sayyed H. [Department of Mechanical Engineering, The University of Birjand, PO Box 97175 /615, Birjand (Iran, Islamic Republic of)], E-mail: shhashemi@birjand.ac.ir

    2008-12-15

    Conventional Charpy based failure models for gas transportation pipelines recommend the minimum fracture energy for safe performance of these structures. In recent years however, full-scale burst experiments have shown that such models cannot fully guarantee the safety of higher grade pipeline steels. One possible reason for this discrepancy, which is further investigated in this research, is that Charpy energy inherently contains both fracture and non-fracture related energy. To separate this, energy partitioning analysis was used. First, the overall fracture energy of X70 steel is measured experimentally on an instrumented Charpy rig. Next, the measured energy is divided into fracture initiation and propagation parts using load-displacement data. It appeared from test results that a significant amount of energy was consumed in non-fracture related processes. From this, correction factors were suggested for possible use in current industry failure models. Interestingly, these corrections factors agreed well with those reported from full-thickness burst tests for tough pipeline steels.

  2. Microbial Corrosion of API 5L X-70 Carbon Steel by ATCC 7757 and Consortium of Sulfate-Reducing Bacteria

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    Arman Abdullah

    2014-01-01

    Full Text Available Various cases of accidents involving microbiology influenced corrosion (MIC were reported by the oil and gas industry. Sulfate reducing bacteria (SRB have always been linked to MIC mechanisms as one of the major causes of localized corrosion problems. In this study, SRB colonies were isolated from the soil in suspected areas near the natural gas transmission pipeline in Malaysia. The effects of ATCC 7757 and consortium of isolated SRB upon corrosion on API 5L X-70 carbon steel coupon were investigated using a weight loss method, an open circuit potential method (OCP, and a potentiodynamic polarization curves method in anaerobic conditions. Scanning electron microscopy (SEM and energy dispersive X-ray spectroscopy (EDS were then used to determine the corrosion morphology in verifying the SRB activity and corrosion products formation. Results from the study show that the corrosion rate (CR of weight loss method for the isolated SRB is recorded as 0.2017 mm/yr compared to 0.2530 mm/yr for ATCC 7757. The Tafel plot recorded the corrosion rate of 0.3290 mm/yr for Sg. Ular SRB and 0.2500 mm/yr for Desulfovibrio vulgaris. The results showed that the consortia of isolated SRB were of comparable effects and features with the single ATCC 7757 strain.

  3. Study of texture and microstructure evaluation of steel API 5L X70 under various thermomechanical cycles

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    Masoumi, Mohammad, E-mail: Mohammad@alu.ufc.br; Herculano, Luis Flavio Gaspar; Ferreira Gomes de Abreu, Hamilton

    2015-07-15

    This work studies the influence of different thermomechanical paths on the microstructure and crystallographic texture across the thickness of API 5L X70 pipeline steel manufactured via hot rolling using X-ray diffraction (XRD), scanning electron microscope (SEM), and electron backscattered diffraction (EBSD). The starting materials were controlled hot-rolled at 1000 °C to 44% and 67% reductions and subsequently heat treated with such processes as annealing, water quenching and quench tempering at three different temperatures to evaluate the microstructure and crystallographic texture changes across the thickness. The banded ferrite-pearlite microstructure of the initial material was changed to acicular ferrite, quasi-polygonal ferrite, granular bainite, martensite and retained austenite via different heat treatments. Moreover, different thermomechanical paths induced crystallographic texture variations across the thickness, e.g., {112}//ND, {111}//ND (γ fibre), and {011}//ND fibres dominated on the surface plane in contact with the rolls, whereas {001}//ND and particularly the (001)[1 1 0] texture component developed in the centre plane on which shear deformation has a zero value in this region. In this study, a simple interpretation of texture evolution was analyzed by comparison with the orientation changes that occurred during different rolling schedules and post-treatment processes.

  4. Study of API 5L X70 steel corrosion processes when in contact with some Brazilian soils; Estudo dos processos de corrosao de acos API 5L X70 em contato com alguns dos solos do Brasil

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    Jesus, Sergio Luis de

    2007-07-01

    Pipelines, fuel storage tanks and other metallic structures are in permanent contact and exposed to different types of soils, of horizons or layers, or of soil aggressiveness. This interaction may cause expressive damages to the environment and to the planned work. Contamination may occur due to leakage of stored products, splitting during transportation, accidents caused by pipelines without extensive maintenance. The result of these accidents could be, among others, some financial losses. In order to recognize the dynamic interactions between metallic surfaces and the environment it is crucial to have preventive actions and to develop better-applied materials. API steel 5L X70 has been used in structures of low and high pressure with high mechanical strength and corrosion and, even so, it is susceptible to etching corrosion since it is in contact with different environments from mangrove regions to industrial environments. The present case evaluated the role of 5L X70 API steel in contact with different soil horizons representative of the Brazilian soil. This investigation correlated chemical species with solute ions in soil solution, secondary and primary phase minerals besides physical and chemical characteristics as pH, electric conductivity, total dissolved solids, among others, to the results of corrosion resistance and ways of corrosion. The evaluation was carried out using x-ray diffractometry, scanning electron microscopy, total reflection x-ray fluorescence, fuel injection flow besides texture and gravimetric analyses to soil characterization and mineralogy, identification of corrosion products, soil solution analyses, evaluation of tested materials and classification of ways and types of corrosion. This was an attempt to integrate the data to a better understanding of the process involving reagents and products. The results showed that different soil horizons such as different types of analyzed soils produce specific etching in metallic structures

  5. Hardness and microstructural characterization of API 5L X70 steel pipes welded by HF/ERW process; Caracterizacao microestrutural e de dureza em tubos de aco API 5L X70 soldados pelo processo HF/ERW

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    Calcada, Mauricio Vieira; Voorwald, Herman Jacobus Cornelis; Nascimento, Marcelino Pereira do [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia

    2010-07-01

    The materials that stand in the manufacture of steel pipes are called API, that should have, high mechanical resistance, high corrosion resistance, high fatigue resistance, good weldability, and other properties. Thus, the purpose of this project was to evaluate the microstructure and hardness of welded joints by the HF/ERW process of API 5L X70 steel pipes. The microstructural analysis was performed using a surface finish with grit sizes from 220 to 25 {mu}m e polishing with diamond paste from 9 {mu}m to 0.05 {mu}m; the revelation was made with 3% Nital attack. The Vickers hardness was performed across the welded joint by 33 points to indentation. The results were: 80.5 {+-} 3.4% of ferrite and 19.5 {+-} 3.4% of perlite for microanalysis. As for hardness, the values were: 215.69 HV10 for weld line, 218.65 HV10 for ZTA and 218.95 HV10 for base metal. (author)

  6. Residual stress evaluation by X-Ray diffraction and hole-drilling in an API 5L X70 steel pipe bent by hot induction

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    Ceglias, Rodrigo Braga; Alves, Juciane Maria; Botelho, Ramon Alves; Baeta Junior, Eustaquio de Souza; Santos, Igor Cuzzuol dos; Moraes, Nicki Robbers Darciano Cajueiro de; Oliveira, Rebeca Vieira de; Diniz, Saulo Brinco; Brandao, Luiz Paulo, E-mail: brandao@ime.eb.br [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Secao de Engenharia Mecanica e de Materiais

    2016-09-15

    The API 5L X70 steel is used in high-pressure gas transmission pipelines. Because of this, knowledge of presence of residual stress and their magnitude is important to assess the material integrity in service. For the pipeline manufacturing, tubes need to be curved which is often made using the hot induction bending process. This process can introduce different residual stress depending of tube position. For this research, in order to evaluate the residual stress, was used an API 5L X70 tube that was previously curved by hot induction process. Samples were taken from the extrados, intrados, neutral line and straight section of the curved tube. Residual stresses were studied by two conventional methods: X-Ray Diffraction (XRD) and Hole-Drilling, which are destructive and non-destructive methods, respectively, in order to assess their qualitative responses. Each of these methods presents particular methodologies in sample preparation and material analysis, but also they differ in factors such time consumption and cost of the analysis. The qualitative responses obtained by the two different methods were comparable and satisfactory and pointed out the existence of a compressive residual stress state in steel pipe. (author)

  7. Technological impact in steels degree API 5L X-70 for the manufacture of resistant ducts of 36 inches of diameter to the bitter gas; Impacto tecnologico de aceros grado API 5L X-70 para la fabricacion de ductos de 36 pulgadas de diametro resistentes al gas amargo

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    Aramburo Perez, G.; Garcia Galan, S.; Perez Campos, R.; Juarez Islas, J.A. [Facultad de Quimica, UNAM, Mexico, D.F. (Mexico)

    2004-03-01

    , cumplen con las propiedades del acero grado API 5L X-70, las cuales son requeridas en los tubos de acero por la industria petrolera.

  8. Behavior in fatigue of longitudinal welded joints of pipeline API 5L X-70 steel at constant and variable amplitude; Comportamento em fadiga de juntas soldadas longitudinais de aco para dutos API 5L X-70 em amplitude constante e variavel

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    Beltrao, Marcelo A.N.; Reis, Felippe T.C.; Castrodeza, Enrique M.; Bastian, Fernando L. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

    2005-07-01

    The fatigue behavior of base metal, weld metal and heat affected zone of longitudinal welded joints of API 5L X-70 pipeline steel used in oil and gas transportation were studied. Fatigue tests were carried under load control for R = 0.1 and 0.5 with constant and variable amplitude, in this case with application of alternate tensile overloads (75 and 100% of maximum load) at 0,5 mm crack growth intervals. The fatigue tests results were obtained by a vs. N and da/dN vs. {delta}K curves. It can be inferred from a vs. N curves that the specimens submitted to R = 0.5 showed smaller fatigue lives than the ones under R = 0.1, with application of overloads or not. The da/dN vs. {delta}K curves exhibited the highest propagation rates for welded joints submitted to R = 0.5. The overloads promoted delay on crack growth at the three regions of the welded joints, the effect being more pronounced for R 0.1. However, for both R values, the effect of crack propagation delay with the overloads decreased with the increase of {delta}K value. (author)

  9. Determination of acoustoelastic constant in API-5L-X70 welded pipes; Determinacao da constante acustoelastica de tubos API-5L-X70 com solda

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    Bittencourt, Marcelo de Siqueira Queiroz; Fonseca, Manoel Antonio da Costa [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Oliveira, Carlos Henrique Francisco de [PETROBRAS S.A., Rio de de Janeiro, RJ (Brazil)

    2008-07-01

    To preserve the environment and avoid financial losses resulting from leaks in the transport of natural oil and gas the industry is particularly concerned to ensure the structural integrity of their pipelines. Grounded pipes may be exposed to damages due to unstable soil movement, and in extreme cases, to failure. Then, techniques to assess stress in pipelines are of central importance. The ultrasonic birefringence technique is an efficient method to measure residual stress. It is based on the changing velocity of the shear wave when it crosses a material under stress; this phenomenon is known as acoustoelasticity. The knowledge of the parameter called acoustoelastic constant is necessary to measure stress using this technique. By the mechanical conformation in the manufacture of welded tubes, from rolled plates, different anisotropy degrees are showed around the cross section of these tubes. In this paper it was studied the acoustoelastic constant for the API-5L-X70 steel pipes, with different thicknesses, diameters and manufacturing processes so as to be able to use this technique to stress measurement in pipelines. (author)

  10. Source and Control of Nitrogen for X70 Pipeline Steel

    Institute of Scientific and Technical Information of China (English)

    Min WANG; Yan-ping BAO

    2016-01-01

    The effects of some key factors on nitrogen absorption during the smelting process of X70 pipeline steel were studied,and the source of nitrogen pick-up was analyzed to find the bottleneck for nitrogen control.A series of measures were put forward to decrease the nitrogen pick-up.The results indicated that an exponential relationship existed between the nitrogen absorption index and the free oxygen in molten steel.Nitrogen absorption index could decrease below 0·3 when free oxygen in molten steel was above 100×10-6 after tapping.For low sulfur killed steel, the nitrogen absorption ratio and sulfur content satisfied a linear relationship with a slope of -0·007.Low free-oxy-gen and sulfur were beneficial to the deep desulfurization during vacuum treatment.The contradiction of high desul-furization ratio and low nitrogen pick-up during LF process could be resolved by skimming oxidizing slag after tap-ping and making new high basicity top slag.After optimization,the average content of nitrogen in final product de-creased from 46×10-6 to 35×10-6 .

  11. Effect of Environmental Factors on Electrochemical Behavior of X70 Pipeline Steel in Simulated Soil Solution

    Institute of Scientific and Technical Information of China (English)

    ZHANG Liang; LI Xiao-gang; DU Cui-wei

    2009-01-01

    Potentiodynamic polarization measurement was used to investigate the effects of temperature, dissolved ox-ygen concentration and pH on the electrochemical behavior of X70 pipeline steel in simulated solution according to the orthogonal testing method. The results showed that temperature, dissolved oxygen concentration and pH had great influence on corrosion current density (icorr)of X70 steel. Corrosion current density of X70 steel was most influenced by dissolved oxygen concentration in simulated solution. The corrosion degree of X70 steel was the least under the environment of low temperature, deficient oxygen and weak acid.

  12. Development of API 5L X70 and X80 in the Brazilian Vallourec and Mannesmann Tubes industry; Desenvolvimento de acos API 5L X70 e X80 na Vallourec e Mannesmann Tubes

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    Silva, Julio M. Silveira e; Carvalho, Ricardo N. de [Vallourec and Mannesmann Tubes - V e M do Brasil, Belo Horizonte, MG (Brazil)

    2000-07-01

    The demand for seamless pipes with resistance higher than those for API 5L X60 and X65 grades has increased in the last years. They are traditionally used up to now for applications on rigid risers for production and exportation and line pipes for oil and gas. In the case of seamless pipes, the great challenge is to fulfill the requirements of mechanical properties for X70 and X80 grades, quenched and tempered, with values of carbon equivalent low enough to assure a good weldability. This paper presents the results obtained by Vallourec and Mannesmann Tubes - V and M do Brazil on producing seamless pipes of X70 and X80 API grades, with outside diameter lower than 8 5/8{sup (} 219,1 mm ) and wall thickness up to 0,562{sup (} 14,3 mm ). Results of tensile, Charpy notch impact resistance and hardness tests are shown. Hydrogen-Induced and Environmental Cracking tests were also carried out, since for some applications is required a good resistance to these kinds of embrittlement mechanisms. The mechanical properties, microstructure and physical characteristics of welded joints were also evaluated. The results obtained up to now are quite promising, showing good suitability to the aimed final applications. (author)

  13. Tension fracture behaviors of welded joints in X70 steel pipeline

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The surface of welded joints in X70 steel pipeline was processed by laser shock wave, its mechanical behaviors of tension fracture were analyzed with tension test,and the fracture morphologies and the distributions of chemical element were observed with scanning electron microscope and energy dispersive spectrum,respectively.The experimental results show that the phenomenon of grain refinement occurs in the surface of welded joints in X70 steel pipeline after the laser shock processing,and compressive re...

  14. Research & Development of Grade X70 LSAW Steel Pipes for West-East Gas Pipeline

    Institute of Scientific and Technical Information of China (English)

    WangXiaoxiang; SunQi

    2004-01-01

    In this article the research and development of X70 large diameter longitudinal seam submerged arc welded (LSAW) steel pipes for West-East Gas Transportation Pipeline project (WEGTP) in China are introduced, including the key technique, fabrication of pipe production line, mass production and the latest progress of LSAW steel pipe technique.

  15. Analysis on the Nitrogen Control of Pipeline Steel X70 in LF Process%X70管线钢LF控氮工艺分析

    Institute of Scientific and Technical Information of China (English)

    胡国旭

    2012-01-01

    The production process for X70 pipeline steel and the control nitrogen factors in LF process were comprehensively analyzed. The results show that the nitrogen pick-up in liquid steel is mainly attributed to the liquid steel exposed to atmosphere at the desulfurization stage under the white slag conditions in LF processs. Accordingly, six key technologies of nitrogen control for pipeline steel X70 from BOF tap to LF end-point were proposed. According to LF practice, constant perfecting and optimizing its technical parameters can lay a theoretical and technological foundation for producing high grade steel containing lower nitrogen.%对X70管线钢生产工艺及LF过程控氮因素进行了综合分析.结果表明,LF工况条件下造白渣脱硫阶段的“钢液裸露”是造成钢液增氮最为主要的原因.在此基础上提出了从BOF出钢到LF处理结束等6项X70管线钢LF控氮工艺要点.根据LF生产实践不断完善与优化其各环节的技术参数,为生产更低含氮量要求的高级别钢种奠定理论与工艺基础.

  16. CREVICE CORROSION BEHAVIOR OF X70 STEEL IN HCO3- SOLUTION UNDER CATHODIC POLARIZATION

    Institute of Scientific and Technical Information of China (English)

    C.W.Du; X.G.Li; X.Chen; P.Liang; H.Guo

    2008-01-01

    The crevice corrosion behavior of X70 steel was investigated with a wedge-shaped crevice assembly under-1000 mV (SCE) cathodic polarization in the solutions with various HCO3- concentrations.The potential,current,pH and the oxygen content within the crevice were measured with or without outside coupled specimen.The re-sults indicated that the polarization potential of X70 steel in the crevice dropped with the increase of time under the cathodic polarization.There was a remarkable in-fluence of HCO3- concentration on the potential of X70 steel in the crevice.When HCO3- concentration was up to 0.125%,the surface of the metal was covered with the corrosion products that resulted in the polarization extent of X70 steel decreased.The pH value in the crevice rose and it dropped gradually from the crevice mouth to the bottom under the cathodic polarization.With the increasing of HCO3- concentration, the hydrolyzation reaction of metal in the crevice bottom aggravated.Most of the dis-solved oxygen in the crevice was consumed by the cathodic current.The maximum cathodic current on the metal surface was at the crevice mouth and it was much more than that at the crevice bottom.

  17. Field corrosion characterization of soil corrosion of X70 pipeline steel in a red clay soil

    Institute of Scientific and Technical Information of China (English)

    Shengrong Wang; Cuiwei Dun; Xiaogang Li; Zhiyong Liunn; Min Zhu; Dawei Zhang

    2015-01-01

    The corrosion behavior of X70 pipeline steel buried in red soil environment has been studied. The surface morphology and elemental distribution were determined by scanning electron microscopy (SEM),energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The corrosion kinetics was evaluated by weight loss measurement. The results show that in red soil, the corrosion rate of X70 steel decreases with time, and follows the exponential decay law. General corrosion with non-uniform and localized pitting occurred on the steel surface.α-FeOOH was the dominate products during corrosion in whole buried periods, and the corrosion products exhibited well protective properties. The potentiodynamic polarization tests revealed that icorr decreased with time, indicating the improvement of corrosion resistance. The results of Electrochemical impendence spectroscopy (EIS) are consistent with potentiodynamic polarization tests.

  18. Field corrosion characterization of soil corrosion of X70 pipeline steel in a red clay soil

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    Shengrong Wang

    2015-06-01

    Full Text Available The corrosion behavior of X70 pipeline steel buried in red soil environment has been studied. The surface morphology and elemental distribution were determined by scanning electron microscopy (SEM,energy dispersive X-ray spectroscopy (EDS, and X-ray diffraction (XRD. The corrosion kinetics was evaluated by weight loss measurement. The results show that in red soil, the corrosion rate of X70 steel decreases with time, and follows the exponential decay law. General corrosion with non-uniform and localized pitting occurred on the steel surface. α-FeOOH was the dominate products during corrosion in whole buried periods, and the corrosion products exhibited well protective properties. The potentiodynamic polarization tests revealed that icorr decreased with time, indicating the improvement of corrosion resistance. The results of Electrochemical impendence spectroscopy (EIS are consistent with potentiodynamic polarization tests.

  19. Development of high strength pipes grade API 5L X70 PSL2 offshore by the HFIW Process (High Frequency Induction Welding)

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    Cordeiro, Wilson R.; Melo, Luis C.R.; Gomes, Igor O.; Boni, Luiz P.; Sanctis, Marco A.M. di [Apolo Tubulars, Lorena, SP (Brazil)

    2009-07-01

    High strength pipes can be manufactured with excellency in dimensional tolerances, rapidity and efficiency through HFIW process (High Frequency Induction Welding). API 5L 6 5/8 x 0,374 in pipes were made of thin, hot rolled and coiled plates with dimensional 9,300 x 1.040,0 x 140.000 mm. Mechanical tests, chemical and microstructural analysis were performed. For the microstructural analysis, ferrite and perlitic structure were detected. All the results obtained are according to API 5L, 44{sup th} edition, 2008 for the grade API 5L X70 PSL2 Offshore. (author)

  20. CORROSION INHIBITION OF X70 STEEL IN SALINE SOLUTION SATURATED WITH CO2 BY THIOUREA

    Institute of Scientific and Technical Information of China (English)

    X.Y. He; H.Y. Deng; R. Li; X.D. Fei; H.Y. Wang; Z.Y. Deng

    2008-01-01

    Corrosion monitoring techniques were performed on X70 steel in saline solution saturated with CO2 with and without thiourea additives within the concentration range 5-25 mg/L. It was found that when the concentration of the inhibitors were increased, the inhibitor efficiencies(IE) of thiourea varied with solution temperature and immersion time. The results indicated that thiourea had the highest inhibition efficiency. The potentiondynamic polarization studies revealed that thiourea are mixed-type inhibitor that mainly restrains the anodic process.

  1. Effects of Cl- and SO2-4 Ions on Corrosion Behavior of X70 Steel

    Institute of Scientific and Technical Information of China (English)

    Junwei WU; Xiaogang LI; Cuiwei DU; Song WANG; Yiquan SONG

    2005-01-01

    Corrosion behaviors of X70 steel were studied by means of electrochemical experiments and morphology observation.First, through potentiodynamic polarization in solution of various Cl- ions concentration, it was found that Epit began to appear in solution of Cl- concentration above 0.1 mol/L, and there was a critical point of Cl- concentration between 0.05 mol/L and 0.1 mol/L, below which the extent of pitting and general corrosion were trivial, while in solution of Cl- concentration above 0.1 mol/L, general and pitting corrosion became greater as the increasing of Cl- concentration. All of them were confirmed by the SEM observations after anodic polarization. Second, via the potentiodynamic polarization curves of X70 steel in 0.5 mol/L Cl- solution with 0, 0.05, 0.5 and 1 mol/L SO42-ions, it was found SO42- ions were able to inhibit corrosion aroused from Cl- ions, accordingly a model was set up to describe the process. In addition, to further explore the inhibited effect of SO42- ions, EIS was used in solutions of different Cl- and SO42- concentrations, the results revealed that the e(ectrochemical resistance has a relation with the [SO42-]/[Cl-], that was, the bigger the value of [SO42-]/[Cl-], the greater the electrochemical resistance.

  2. Effect of Microstructure on HIC Susceptibility of API X70MS Linepipe Steel

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    Sung, Joon-Ho; Sim, Ho-Seop; Park, Byung-Gyu [Dongkuk Steel R and D Center, Pohang (Korea, Republic of); Cho, Kyung-Mox [Pusan National University, Busan (Korea, Republic of)

    2017-06-15

    The resistance of hydrogen induced cracking (HIC) was investigated with different microstructures of API X70MS steel. Ferrite/acicular ferrite (F/AF), deformed ferrite/acicular ferrite, ferrite/bainite (F/B) and single acicular ferrite (AF) were obtained by thermo-mechanical controlled process (TMCP) with changing rolling and cooling conditions. HIC resistance was found to be affected by the type as well as morphology of the microstructure, and thus the behavior of crack initiation and propagation could be analyzed. It was found that single AF and deformed F/AF with uniformly distributed dislocation reduced HIC initiation. Banded microstructure with a hardness value below 250 HV, such as AF, showed good HIC propagation resistance due to high toughness. AF generally exhibited excellent crack initiation and propagation resistance, namely the best HIC susceptibility performance. AF might redeem the HIC resistance for the banded microstructure also.

  3. Oblique Y-groove cracking test of the welding cold cracking susceptibility of domestic X-70 pipeline steel

    Institute of Scientific and Technical Information of China (English)

    陈丽萍; 杜则裕; 李云涛; 李九生

    2002-01-01

    "Gas Transmitting From West to East Project" is significant. It should ensure the welding quality and safety of pipeline. The task is very arduous to guarantee the quality of the project in the condition of long line, complex weather and geology features. In this paper, the welding cold cracking susceptibility of domestic X-70 pipeline steel adopted by the project, which is one of the most interesting questions of welding quality about petrol pipeline, was studied by means of oblique Y-groove cracking test. The crack ratio of surface and section was tested under the conditions of different welding materials and preheat temperature .The X-70 pipeline steel has good crack resistance. The research has important value for the construction of large-scale pipeline engineering and the application of domestic X-70 pipeline steel.

  4. Relationship between electrochemical characteristics and SCC of X70 pipeline steel in an acidic soil simulated solution

    Institute of Scientific and Technical Information of China (English)

    Zhiyong LIU; Xiaogang LI; Yingrui ZHANG; Cuiwei DU; Guoli ZHAI

    2009-01-01

    Stress corrosion cracking (SCC) of X70 pipeline steel in simulated solution of the acidic soil in Yingtan in China was investigated using slow strain rate test (SSRT), SEM and potentiodynamic polarization technique. Experiment results indicate that X70 steel is highly susceptible to SCC as applied potential reduces, which is manifested in loss of toughness and brittle fracture. Constant polarization current can detect the occurrence of SCC. The lower the polarization current is the sooner stress corrosion cracking occurs. The SCC mechanisms are different at varying potentials. When potential is higher than open circuit potential, anodic process controls SCC, whereas when potential is far lower than open circuit potential, cathodic process controls SCC, and between these two potential regions, a combined electrochemical process controls the SCC. Stress or strain has a synergistic effect with electrochemical reactions to accelerate the cathodic hydrogen evolution process, which makes the X70 pipeline steel to be more susceptible to SCC.

  5. Study of sulphate-reducing bacteria corrosion in the weld joint for API X-70 steel

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    Flores, J. E.; Patino-Carachure, C.; Alfonso, I.; Rodriguez, J. A.; Rosas, G.

    2012-11-01

    The corrosion behavior originated by sulfate-reducing bacteria (SRB) was studied in two regions of welded API X-70 steel pipeline. The studies were focused on base material (BM) and heat affected zone (HAZ), from the internal region of the pipe. SRB were extracted from oil and grown in a Postgate medium. Corrosion was evaluated at 60 degree centigrade for times between 5 and 64 days. Potentiodynamic polarization curves, obtained by electrochemical techniques, indicated surface activation at short times. Structural and morphological characterizations were carried out by scanning electron microscopy (SEM) and optical microscopy (OM). H{sub 2}S concentration and pH were also measured. Results showed an important increase in the corrosion damage up to 20 days, influenced by the SRB activity, which lead to a maximum of H{sub 2}S (pH minimum). It was found a localized corrosion attack in the HAZ in a higher quantity compared to BM; and the formation of a thin film on the steel surface, originated by corrosion products and bacterial activity. (Author) 15 refs.

  6. Slow strain rate corrosion and fracture characteristics of X-52 and X-70 pipeline steels

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    Contreras, A. [Instituto Mexicano del Petroleo, Programa de Investigacion y Desarrollo de Ductos, Eje Central Lazaro Cardenas 152, San Bartolo Atepehuacan, C.P. 07730, Mexico, D.F. (Mexico)]. E-mail: acontrer@imp.mx; Albiter, A. [Instituto Mexicano del Petroleo, Programa de Investigacion y Desarrollo de Ductos, Eje Central Lazaro Cardenas 152, San Bartolo Atepehuacan, C.P. 07730, Mexico, D.F. (Mexico); Salazar, M. [Instituto Mexicano del Petroleo, Programa de Investigacion y Desarrollo de Ductos, Eje Central Lazaro Cardenas 152, San Bartolo Atepehuacan, C.P. 07730, Mexico, D.F. (Mexico); Perez, R. [Instituto Mexicano del Petroleo, Programa de Investigacion y Desarrollo de Ductos, Eje Central Lazaro Cardenas 152, San Bartolo Atepehuacan, C.P. 07730, Mexico, D.F. (Mexico)

    2005-10-25

    The susceptibility to stress corrosion cracking (SCC) in a NACE solution saturated with H{sub 2}S, of the X-52 and X-70 steels was studied using slow strain rate tests (SSRT) and electrochemical evaluations. SCC tests were performed in samples which include the longitudinal weld bead of the pipeline steels and were carried out in the NACE solution at both room temperature and 50 deg. C. After failure, the fracture surfaces were observed in a scanning electron microscope (SEM) and the chemical analysis were obtained using X-rays energy dispersive (EDXs) techniques. The specimens tested in air, exhibited a ductile type of failure, and whereas, those tested in the corrosive solution showed a brittle fracture. Specimens tested in the NACE solution saturated with H{sub 2}S presented high susceptibility to SCC. Corrosion was found to be an important factor in the initiation of some cracks. In addition, the effect of the temperature on the corrosion attack was explored. The susceptibility to SCC was manifested as a decrease in the mechanical properties. Potentiodynamic polarization curves and hydrogen permeation measurements were made. The diffusion of atomic hydrogen was related to this fracture forms. The hydrogen permeation flux increased with the increasing of temperature.

  7. Research on anti-corrosion property of rare earth inhibitor for X70 steel

    Institute of Scientific and Technical Information of China (English)

    ZHU Yanhua; ZHUANG Jia; YU Yongsheng; ZENG Xianguang

    2013-01-01

    Three kinds of rare earth nitrates were adopted to sodium molybdate to get three kinds of LnN-M compounded inhibitors (La(NO3)3+Na2MoO4(LaN-M),Ce(NO3)3+Na2MoO4(CeN-M),Pr(NO3)3+Na2MoO4(PrN-M)).The combination of weight-loss method and the electrochemical test,was used to evaluate and analyze the corrosion inhibition efficiency of these LnN-M inhibitors to make the research on their corrosion inhibition performance,and the sequential order of their performance was found as follows:CeN-M> LaN-M>PrN-M,among which,the inhibition efficiency of CeN-M for the X70 steel could reach 98.21%.The synergism parameters were calculated by weight-loss method,these computational data indicated that the synergistic effect between rare earth nitrates and sodium molybdate was obvious and significant.Surface morphology,chemical composition and phase components of the precipitation films were tested for discussing the mechanism of LnN-M inhibitors.The outer electronic configuration of the lanthanide was found to have an important influence on the inhibition efficiency.The CeN-M inhibitor was discovered to have the best inhibition effect with the amorphous cerium oxides.The results of this research revealed that the precipitation films formed on the surface of the steel samples had a crucial influence on the inhibition efficiencies after adding LnN-M inhibitors.

  8. Study of sulphate-reducing bacteria corrosion in the weld joint for API X-70 steel

    Directory of Open Access Journals (Sweden)

    Flores, J. E.

    2012-10-01

    Full Text Available The corrosion behavior originated by sulfate-reducing bacteria (SRB was studied in two regions of welded API X-70 steel pipeline. The studies were focused on base material (BM and heat affected zone (HAZ, from the internal region of the pipe. SRB were extracted from oil and grown in a Postgate medium. Corrosion was evaluated at 60 °C for times between 5 and 64 days. Potentiodynamic polarization curves, obtained by electrochemical techniques, indicated surface activation at short times. Structural and morphological characterizations were carried out by scanning electron microscopy (SEM and optical microscopy (OM. H2S concentration and pH were also measured. Results showed an important increase in the corrosion damage up to 20 days, influenced by the SRB activity, which lead to a maximum of H2S (pH minimum. It was found a localized corrosion attack in the HAZ in a higher quantity compared to BM; and the formation of a thin film on the steel surface, originated by corrosion products and bacterial activity.

    El comportamiento ante la corrosión, originada por bacterias sulfato-reductoras (SRB, fue estudiado en dos regiones de un tubo de acero soldado API X-70. Los estudios se enfocaron en el material base (BM y la zona afectada térmicamente (HAZ, en la parte interna del tubo. Las SRB fueron extraídas del petróleo y cultivadas en un medio Postgate. El comportamiento a la corrosión fue evaluado a una temperatura de 60 °C, por periodos comprendidos entre 5 y 64 días. El análisis de las curvas de polarización potenciodinámicas, obtenidas por técnicas electroquímicas, indicó la activación de la superficie para tiempos cortos. La superficie fue caracterizada estructural y morfológicamente mediante microscopia electrónica de barrido (SEM, así como mediante microscopía óptica (OM. La concentración de H2S y el pH también fueron medidos. Los resultados mostraron un aumento importante de la corrosi

  9. DECREASING PITTING SUSCEPTIBILITY OF PASSIVE FILMS ON X70 PIPELINE STEEL IN NaCl SOLUTIONS BY ILLUMINATION

    Institute of Scientific and Technical Information of China (English)

    W.C. Zhu; W.H. Leng; J.Q. Zhang; C.N. Cao

    2006-01-01

    The influence of UV illumination on passivity and pitting susceptibility on X70 pipeline steel in a borate buffer (pH=8.4) solution containing NaCl is described. It is observed that illumination of the sample leads to a decrease in its pitting susceptibility as indicated by pitting potential and incubation time measurements in chloride containing electrolytes. This effect is strongly dependent on the applied potential during passivation. The electronic properties of the passive films on X70steel were studied by Mott-Schottky analysis and photocurrent transient measurements. The results indicated that illumination during passivation led to modifications in the electronic properties of the passive films, mainly to a decrease of the bulk doping and an increase in the surface state density. The cause for the decrease in the pitting susceptibility is preliminary explained in terms of such modifications of the passive film.

  10. Stress corrosion cracking behaviour in welded X-70 linepipe steel under near-neutral pH conditions

    Energy Technology Data Exchange (ETDEWEB)

    Adeleke, A.H.; Luo, J.L.; Ivey, D.G. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

    2005-07-01

    This study examined the relationship between the near neutral pH stress corrosion cracking (SCC) resistance and the yield strength of pipelines steels. In particular, double-edge-notched flat tensile samples of X70 steel were used for both slow strain-rate testing (SSRT) and cyclic loading testing with the notch located in the zone of interest. This included the weld metal (WM), base metal (BM) and heat-affected zone (HAZ). In all samples, the mode of failure was mostly transgranular with cleavage facets around the edges of the fracture surface. One of the objectives of this study was to better understand the microstructural effect of the relationship. The 3 main parameters that were used to assess the SCC susceptibility in a near-neutral pH environment were the elongation ratio, the estimated percentage of the fracture surface that showed brittle fractures, and the relative crack growth at a given exposure time. It was shown that resistance to near-neutral pH SCC depends greatly on the microstructure of the pipeline steels. Fine-grained bainite and ferrite structured steels were found to have a much better combination of strength and SCC resistance compared to ferrite and pearlite structures. The high-to-low sensitivity ranking of the X70 linepipe steel to SCC was established to be: WM is greater than HAZ which is greater than BM. 20 refs., 1 tab., 9 figs.

  11. Electrochemical corrosion behaviour of grade X70 and X80 pipeline steels%X70和X80管线钢的电化学腐蚀行为

    Institute of Scientific and Technical Information of China (English)

    李红英; 康巍; 胡继东; 刘洋

    2011-01-01

    通过极化曲线和交流阻抗谱测试以及OM表面腐蚀形貌观察、SEM和TEM的组织观察,研究了Cl-和SO42-离子对X70和X80两种管线钢腐蚀过程的作用机理与规律。结果表明:Cl-有强穿透性,极易引起点蚀,两种钢的自腐蚀电流密度都随着Cl-浓度的增大而增大,点蚀和全面腐蚀也随之进一步加剧,X70钢在较低浓度的NaCl溶液中出现全面腐蚀和点蚀,X80钢仅在高浓度NaCl溶液中出现明显的点蚀,且在各种不同浓度溶液中腐蚀程度均没有X70钢严重。SO42-在金属表面吸附能力比Cl-强,少量SO42-在金属表面的吸附,造成Cl-的局部含量高,更易引起点蚀,而大量SO42-在金属基体表面覆盖,能阻碍Cl-的影响。X80钢比X70钢有更强的耐腐蚀性,X70钢对SO42-和Cl-的作用更为敏感。%Corrosion mechanism and corrosion process of Cl-and SO42-ions on grade X70 and X80 pipeline steels were studied by means of polarization curves,electrochemical impedance spectroscopy,OM,SEM and TEM.The results show that Cl-has a strong penetrability,leading to pitting corrosion.The corrosion current density of the steels increases and pitting and general corrosion is aggravated with the increase of Cl-concentration in the solution.Pitting and general corrosion of X70 steel occurs in the NaCl solution of low concentration and only obvious pitting corrosion of X80 steel in the NaCl solution of high-concentration is observed and corrosion degree of X80 steel is less than that of X70 steel in same concentration solution.The adsorption ability of SO42-on the surface of metal is stronger than Cl-,a small amount of SO42-that adsorbs on the surface of metal to cause higher local content of Cl-causes more pitting,however a large amount of SO42-can cover on the surface of metal to hinder the influence of Cl-.X70 steel is more sensitive to the effect of SO42-and Cl-compared with X80 steel,and X80 steel exhibits higher corrosion resistance than X70 steel.

  12. Magnetic and other physical properties of X52, X60, X70, and X80 grade linepipe steels

    Energy Technology Data Exchange (ETDEWEB)

    Richter, F. (Mannesmann-Forschungsinstitut GmbH, Duisburg (Germany, F.R.))

    1989-01-01

    The following magnetic properties were determined for X 52, X 60, X 70, and X 80 grade linepipe steels: magnetic induction as a function of magnetic field strength in the form of hysteresis loops, coercive force and saturation magnetisation. In addition, the following physical properties were determined: coefficient of thermal expansion between -180 and 400{sup 0}C, elastic constants between -180 or 20 and 300{sup 0}C, electrical resistivity, thermal conductivity and thermal diffusivity between -180 and 300{sup 0}C. The crystallographic textures of the materials were represented by pole figures. (orig.).

  13. 含腐蚀缺陷X70钢剩余强度分析%Analysis of Residual Strength of X70 Pipeline Steel with Corrosion Defects

    Institute of Scientific and Technical Information of China (English)

    陈平伟; 王峰会; 王绍明

    2011-01-01

    采用ABAQUS有限元数值计算方法,分析了含腐蚀缺陷X70管道的剩余强度.根据相关标准的失效准则,研究了腐蚀的发展规律,并考虑到双腐蚀缺陷对管道剩余强度的影响.结果表明,对于双腐蚀缺陷,管道剩余强度随着两腐蚀轴向间距的增大而增大,最后趋于稳定;管道剩余强度随着两腐蚀缺陷径向夹角的增大而增大,最后趋于稳定.研究结果对于管道的安全运行和维护具有重要的作用.%ABAQUSUS finite element method(FEM) was employed to analyze the residual strength of X70 pipeline with corrosion defects. According to relative failure criteria, the corrosion development law was studied. The results showed that for a pipeline with two corrosion defects, the residual strength increased as the axis distance of two corrosion defects increased. The residual strength increased with the increase of radial angle of two corrosion defects.The results is important to the pipeline's safe operation and maintenance.

  14. Effect of alloy elements on toughness of X70 pipeline steels%微合金元素对X70管线钢韧性的影响

    Institute of Scientific and Technical Information of China (English)

    李红英; 胡继东; 李阳华

    2012-01-01

    Toughness of four X70 pipeline steels with different composition was studied by using charpy impact test and dropweight tear test( DWTT). The effects of microstructure, grain size, grain orientation and misorientation angle distribution, and inclusions on toughness of the steels were analysed by means of optical microscope ( OM ) , scanning electrical microcopy ( SEM ) and the electron backscatter diffraction technique(EBSD). The results show that the eharpy impact toughness and DWTT values of the pipeline steels containing Mo and Ni are higher, the DWTT values of pipeline steels containing Cr are unqualified. The toughness of X70 pipeline steels increases with higher ratio of large angle grain boundaries, less inclusions and finer effective grain size.%研究了4种含不同微合金元素的X70管线钢的韧性,采用夏比冲击试验和落锤撕裂试验,借助金相显微镜(OM)、扫描电镜(SEM)与背散射电子衍射技术(EBSD)等手段,分析了微观组织、晶粒尺寸、晶粒取向及取向差和夹杂物等因素对X70管线钢韧性的影响。结果表明,含Mo、Ni元素的管线钢夏比冲击韧性和落锤性能都较好,含Cr元素的管线钢落锤性能偏低,大角度晶界比率越高,晶粒尺寸越细小,夹杂物含量越少的管线钢具有更高的韧性。

  15. Anodic Dissolution Behavior of the Crack Tip of X70 Pipeline Steel in Near-Neutral pH Environment

    Science.gov (United States)

    Cui, Zhongyu; Wang, Liwei; Liu, Zhiyong; Du, Cuiwei; Li, Xiaogang; Wang, Xin

    2016-12-01

    In this work, the anodic dissolution behavior of the fresh metal surface at crack tip of X70 steel in near-neutral pH environment was investigated using galvanic corrosion simulation method. The solution environment, strain, strain rate, hydrogen enrichment, and fresh metal surface at the crack tip were considered. Corrosion current of the specimen during fast stretching increased linearly with plastic strain. The increment and increase rate of the corrosion current during plastic deformation stage were dependent on the strain rate. Combining Faraday's law and crack tip strain rate equation, the crack growth rate (CGR) induced by the anodic dissolution of the fresh metal surface was calculated. Results show that CGR caused by anodic dissolution was roughly one order lower than that measured on the compact tensile specimen under cyclic load. This finding indicated that hydrogen embrittlement may play a dominate role in stress corrosion crack propagation of pipeline steels in near-neutral pH environment.

  16. Effect of deteriorated microstructures on stress corrosion cracking of X70 pipeline steel in acidic soil environment

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to investigate stress corrosion cracking (SCC) of X70 pipeline steel and its weld joint area in acidic soil environmeat in China,two simulating methods were used: one was to obtain bad mierostructures in heat affected zone by annealing at 1300℃ for 10 rain and then,quenching in water; the other was to get different simulating solutions of acidic soil in Yingtan in southeast China.The SCC susceptibilities of X70 pipeline steel before and after quenching in the simulating solutions were analyzed using slow stain rate test (SSRT) and poteatiodynamic polarization technique to investigate the SCC electrochemical mechanism of different mierostruetures further.The results show that SCC appears in the original mierostrueture and the quenched mierostructure as the polarization potential decreases.Hydrogen revolution accelerates SCC of the two tested materials within the range of-850 mV to -1200 mV vs.SCE.Microstructural hardening and grain coarsening also increase SCC.The SCC mechanisms are different,anodic dissolution is the key of causing SCC as the polarization potential is higher than the null eurreat potential,and hydrogen embrittlemeat will play a more important role to SCC as the polarization potential lower than the null current potential.

  17. Effect of Cyclic Loading on Cracking Behaviour of X-70 Pipeline Steel in Near-Neutral pH Solutions

    Institute of Scientific and Technical Information of China (English)

    Hao GUO; Guangfu LI; Xun CAI; Ruipeng YANG; Wu YANG

    2005-01-01

    The cracking behaviour of X-70 pipeline steel in near-neutral pH solutions was studied under different modes of cyclic loading. The crack propagation process of X-70 pipeline steel under low frequency cyclic loading condition was controlled mainly by stress corrosion cracking (SCC) mechanism. Under mixed-mode cyclic loading, both higher tensile stress and shear stress made cracks easier to propagate. Applied cathodic potentials and high content of carbon dioxide in solutions also promoted the propagation of cracks. The propagation directions of cracks were different under different cyclic loading conditions. Under mode I (pure tensile stress) cyclic loading condition, cracks were straight and perpendicular to the tensile stress axis, while under mixed-mode Ⅰ/Ⅲ (tensile/shear stress) cyclic loading,cracks were sinuous and did not propagate in the direction perpendicular to the main tensile stress axis. Under the mixed-mode cyclic loading, cracks were much easier to propagate, suggesting that shear stress intensified the role of tensile stress. In addition, shear stress promoted the interaction between cracks, resulting in easier coalescence of cracks.

  18. Effect of pH Value on Stress Corrosion Cracking of X70 Pipeline Steel in Acidic Soil Environment

    Institute of Scientific and Technical Information of China (English)

    Zhiyong LIU; Cuiwei DU; Xin ZHANG; Fuming WANG; Xiaogang LI

    2013-01-01

    The effect of pH value on the stress corrosion cracking (SCC) of API X70 pipeline steel in simulated acidic soil solutions was investigated by using slow strain rate test,electrochemical polarization curves,electrochemical impedance spectroscopy,and scanning electron microscopy.pH plays an important role in the susceptibility and electrochemical mechanism of SCC.The pH higher than 5 has no significant effect on electrochemical processes.By contrast,the pH lower than 5 intensifies cathodic hydrogen evolution reactions,thus increasing the cathodic current and corrosion potential.Under different pH values,the SCC mechanism of X70 pipeline steel varies among anodic dissolution (AD),hydrogen embrittlement (HE),and the combination of AD and HE (AD + HE) with variations of applied potential.At-850 mVSCE,the SCC mechanism is HE if pH is less than 4 or AD + HE if pH value is more positive.

  19. 热浸渗铝X70管线钢扩渗工艺研究%Research on Hot Diffusion Aluminizing Process of X70 Pipe Line Steel

    Institute of Scientific and Technical Information of China (English)

    黄敦伟; 胡爱萍; 张宏伟; 孔德军

    2013-01-01

    The relationship between hot diffusion aluminizing temperature,infiltration time and thickness of aluminized coating of X70 pipe line steel was researched by quadratic orthogonal regression testing method.The regression equation of the alloying layer thickness was established.The optimum process for hot diffusion aluminizing treatment was gotten.The surface and interface morphologies of X70 pipeline steel after the aluminizing treatment were observed,and Fe and Al content change by the carbonitride layer were analyzed.The element diffusion mechanism of hot dipping alumetizing process was discussed.The results show that alloying layer thickness is increased with the rising of insulation temperture and the extending of diffusion time.The ideal inoulation temperature is 950 ℃ and time is insulation 6 h.%采用二次正交回归试验方法,研究了X70管线钢热扩渗铝保温温度、扩渗时间与渗铝层厚度的关系,建立了渗层回归方程,得到X70管线钢最优的热扩渗铝工艺参数.观察了X70管线钢热浸渗铝处理后的表面、界面微观形貌,分析了Fe和Al的含量沿渗层的变化情况,并对热浸渗铝过程中的元素扩散机理进行了探讨.结果表明:渗铝层厚度随保温温度的升高和扩渗时间的延长而增大,适宜的保温温度为950℃,扩渗时间为6h.

  20. Study on the microstructure and hardness of in-service welded joint of X70 pipeline steel

    Institute of Scientific and Technical Information of China (English)

    Chen Yuhua; Wang Yong; Liu Geping

    2007-01-01

    Hydrogen induced cracking (HIC) is one of the main problems of in-service welding onto active pipeline. Microstructure and hardness of welded joint have a vital effect on hydrogen induced cracking. The microstructure and hardness of welded joint of X70 pipeline steel were studied using simulation in-service welding device. The results show that the main microstructures of in-service welded seam are grain boundary ferrite, intracrystalline acicular ferrite, as well as small amount of widmanstatten structure. The main microstructures of coarse grain heat-affected zone (CGHAZ) are coarse granular bainite, lath ferrite and martensite. Metastable phases such as martensite and lath ferrite are found in CGHAZ because of the too quick cooling velocity and the hardness of the CGHAZ is high.

  1. Properties of Surface Film on X70 Pipeline Steel in CO32-/HCO3- Environment

    Institute of Scientific and Technical Information of China (English)

    胡钢; 许淳淳

    2005-01-01

    The electrochemical behavior of X70 pipeline steel in (0.5 mol·L-1 Na2CO3+lmol·L-1 NaHCO3) solution was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used to analyze the composition and microstructure of the surface film. The results showed that there were two anodic peaks at -600 mV and -350 inV.The surface film formed at -600 mV mainly consisted of ferrous carbonates and ferrous hydroxycarbonates. It had a small reaction resistance. It was metastable and possessed poor protective property. Numerous pits and microcracks existed on the film, which could be the active paths for the initiation of stress corrosion cracking. The surface film formed at -350 mV, mainly consisted of ferric oxides. It has high reaction resistance and offered good protection for the substrate.

  2. Avaliação da Influência de Tratamentos Térmicos Pós-Soldagem Sobre a Microestrutura e Propriedades Mecânicas de Juntas de um Aço API 5L X70Q

    Directory of Open Access Journals (Sweden)

    Lívia Carla Silva de Araújo

    2015-06-01

    Full Text Available ResumoAços que atendem à norma API 5L são aplicados na construção de dutos e há grande interesse naqueles de maior resistência, como o grau API 5L X70Q. Ainda são escassos os estudos relacionados a tubos sem costura. Durante a montagem, os tubos podem ser soldados por eletrodos revestidos (SMAW e eventualmente sofrer aquecimento indutivo para adequação à topografia do terreno, processos que podem alterar a microestrutura das juntas. Neste trabalho foram obtidas juntas soldadas pelo processo SMAW, a partir de tubo sem costura grau API 5L X70Q. As juntas foram submetidas a tratamentos térmicos pós-soldagem nas temperaturas 920 °C e 600 °C. Foram realizados ensaios de tração, impacto Charpy e microdureza, além de caracterização metalográfica nas amostras de metal base e nas juntas como soldadas e após os tratamentos térmicos. O tratamento térmico a 920 °C promoveu a formação de estrutura ferrita/perlita, com consequente redução na resistência mecânica das juntas a valores inferiores aos especificados para o grau X70Q. Porém, o tratamento térmico a 600 °C mostrou-se benéfico devido à redução da fração volumétrica dos constituintes martensita/austenita e martensita-austenita-bainita, sem reduzir de forma significativa a resistência mecânica e com relativo ganho na tenacidade ao impacto na ZTA e na ZF.

  3. Corrosion resistance of ERW (Electric Resistance Welded) seam welds as compared to metal base in API 5L steel pipes

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Velasquez, Jorge L.; Godinez Salcedo, Jesus G.; Lopez Fajardo, Pedro [Instituto Politecnico Nacional (IPN), Mexico D.F. (Mexico). Escuela Superior de Ingenieria Quimica e Industrias Extractivas (ESIQIE). Dept. de Ingenieria Metalurgica

    2009-07-01

    The corrosion resistance of ERW seam welds and the base metal in API 5L X70 steel pipes was evaluated by Tafel tests. The procedure was according to ASTM G3 standard. The study was completed with metallographic and chemical characterization of the tested zones, that is, the welded zone and the base metal away of the weld. All tests were made on the internal surface of the pipe in order to assess the internal corrosion of an in-service pipeline made of the API 5L X70 steel. The test solution was acid brine prepared according to NACE Publications 1D182 and 1D196. The results showed that the ERW seam weld corrodes as much as three times faster than the base material. This behavior is attributed to a more heterogeneous microstructure with higher internal energy in the ERW seam weld zone, as compared to the base metal, which is basically a ferrite pearlite microstructure in a normalized condition. This result also indicates that pipeline segments made of ERW steel pipe where the seam weld is located near or at the bottom of the pipe are prone to a highly localized attack that may form channels of metal loss if there is water accumulation at the bottom of the pipeline. (author)

  4. Corrosion of A3,20# and X70 Steels in Simulated Flowing Seawater%A3、20#和X70钢室内模拟流动海水腐蚀试验

    Institute of Scientific and Technical Information of China (English)

    程浩力; 刘德俊

    2012-01-01

    设计并建立了实验室模拟流动海水腐蚀试验装置。对A3、20#、X70钢挂片和20#钢管路在流动人工海水中全浸暴露2、4、8、16、32天的腐蚀行为进行了试验研究。试验结果表明,流动海水中碳钢的腐蚀速率先降后升,然后趋于稳定;在动水试验中,锈层分为两层,底层以Fe3O4为主,表层以Fe2O3为主;在静水试验中,锈层以Fe2O3为主。%A simulated flowing seawater corrosion test system was set up,the corrosion behaviors of carbon steels in simulated seawater were studied using the system.The weight loss tests of A3,20# and X70 steels were conducted to show the corrosion rate data in static and flowing seawater for comparison.Results showed that the corrosion of A3,20# and X70 steels was accelerated in the flowing seawater due to the erosion-corrosion effect on the surfaces of metal materials.The corrosion rate showed a decrease first and then an increase,and gradually became stable later.The rust layers were divided significantly into two layers in the flowing water experiment.

  5. PITTING CORROSION OF X70 PIPELINE STEEL IN THE SIMULATED WET STORAGE ENVIRONMENT%X70钢在模拟潮湿存储环境中的点蚀行为

    Institute of Scientific and Technical Information of China (English)

    刘智勇; 董超芳; 贾志军; 李晓刚

    2011-01-01

    Pitting mechanism and behaviour of X70 pipeline steel in humid storage environ ments were investigated using electrochemical polarization curves, electrochemical impedance spec trums (EIS), immersing corrosion tests and corrosion morphology observation through SEM. It was demonstrated that pitting of X70 pipeline steel occurred in simulated moist storage environments, for which the corrosive substances came from the residual species in laminar cooling water introduced during steel manufacture processes. HCO3- and NOJ are passivating agents, Cl- and SO42- would destroyed the passivation layer, which could lead to pitting. In solution with 0.5 mol/L NaHCO3, 0.02 mol/L Cl- was enough to break the passivation layer. Cl- concentration is a key factor for pit ting initiation and propagation. When the Cl- concentration was relatively low, pitting could initiate but was hard to grow up. When the Cl- concentration was moderate (about 0.149 mol/L), pitting sensitivity was the highest because pitting was easy to grow up. However, if the concentration of Cl-was too high, uniform corrosion occurred.%应用电化学极化技术、电化学阻抗谱、模拟浸泡实验,研究了X70钢在模拟潮湿存储环境中点蚀的发生机制及规律.结果表明,X70钢在模拟潮湿存储环境中可以发生点蚀,导致点蚀发生的腐蚀介质来自于层流冷却水中的腐蚀性物质,其中HCO-3和NO-3是致钝剂,而Cl-和SO42-可破坏钝化膜,促进点蚀发生.在0.5 mol/L的NaHCO3介质中当Cl-浓度达到0.02 mol/L时钝化膜即失去保护性.CI-浓度是影响点蚀的萌生和发展的关键因素,当其浓度较低时点蚀容易形核,但仅有少数能够长大;而当其浓度适中(约0.149 mol/L)时点蚀敏感性最高,点蚀容易长大;当其浓度过高时发生均匀腐蚀,点蚀难以长大.

  6. Stress corrosion cracking of X70 pipeline steel in near-neutral pH soil solution

    Energy Technology Data Exchange (ETDEWEB)

    Fang, B.Y.; Wang, J.Q.; Han, E.H.; Zhu, Z.Y.; Ke, W. [Chinese Academy of Sciences, Shenyang (China). State Key Laboratory for Corrosion and Protection, Inst. of Metal Research

    2004-07-01

    Near-neutral pH stress corrosion cracking (SCC) is characterized by wide transgranular cracks with quasi-cleavage on the fracture surface, and there is usually little evidence of general or lateral corrosion. Near-neutral pH SCC is related to dissolution and hydrogen ingress into steel pipes because discharged atomic hydrogen can enter the steel so that cracks are initiated or grown by a combination of dissolution and hydrogen-embrittlement. In this study, the SCC cracking behaviour of an X70 pipeline was investigated using slow strain rate tests (SSRT) and cyclic loading at high R and low frequency in a near-neutral pH soil solution saturated with 5 per cent carbon dioxide (CO{sub 2}) and 95 per cent nitrogen (N{sub 2}). Potentiodynamic polarization analyses and electrochemical impedance spectrum (EIS) analyses were also conducted in order to examine the effect of the concentration of bicarbonate, bubbled gas and the addition of chloride ions on polarization behaviour. Results of the SSRT tests showed that transgranular SCC occurred in the soil solution. Crack initiation was associated with pitting. The pipe's susceptibility to SCC increased with decreases in applied electrochemical potential and strain rate. Cyclic loading tests showed that crack propagation processes were dominated by SCC. At high R and low frequencies, SCC was observed on fatigued, pre-cracked specimens. Results of the electrochemical tests showed that polarization behaviours were influenced by the concentrations of bicarbonate, bubbled gas, and the addition of chloride ions. It was concluded that the addition of chloride ion can influence film stability on pipeline specimen surfaces. 22 refs., 2 tabs., 8 figs.

  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. 多相流动状态下温度对X70钢CO2腐蚀的影响%Effects of Temperature on CO2 Corrosion of X70 Steel under Multiphase Flow Condition

    Institute of Scientific and Technical Information of China (English)

    封子艳; 强超; 杨志刚; 朱世东; 魏彦林; 崔铭伟

    2016-01-01

    目的:提高多相流动状态下温度对X70钢CO2腐蚀机理的认识。方法采用自制实验装置和挂片实验,模拟起伏管路段塞流动条件下X70钢的CO2腐蚀状态,通过电子显微镜和电化学在线监测等手段对试样表面形貌、腐蚀速率以及在线腐蚀情况进行观察和分析,侧重研究多相流动状态下温度对X70钢CO2腐蚀速率的影响。结果当温度达到90~98℃时,由于腐蚀产物膜的影响,CO2分压对腐蚀速度影响甚微,腐蚀速度降至较低水平。当温度在60~80℃之间时,腐蚀挂片表面的腐蚀状态不稳定,出现局部腐蚀或均匀腐蚀,当CO2分压较低时(如0.15 MPa),易形成均匀腐蚀;当CO2分压较高时(如0.6 MPa),易形成局部腐蚀。当温度在40~80℃之间时,随着CO2分压的增加,腐蚀速率达到最高值的温度越来越高,腐蚀速率达到最高值的温度范围一般保持在40~80℃之间。结论温度对X70钢CO2腐蚀的影响与CO2分压密切相关,相同温度下,随着CO2分压的增加,腐蚀速率增大,相应的腐蚀速率达到最高值的温度也越来越高;孤立地说某一温度值下,CO2腐蚀速率达到最高值这一说法不准确。%ABSTRACT:Objective To improve the understanding of CO2 corrosion mechanism at different temperature under multiphase flow condition. Methods The CO2 corrosion status of X70 steel under the condition of plug flow was simulated using the self-made ex-perimental device and the hanging plate experiment. The surface morphology, corrosion rate and online coupon corrosion situation were observed and analyzed by electron microscopy and electrochemical monitoring. The effect of temperature on the CO2 corrosion rate of X70 steel was focused on. Results The CO2 partial pressure had little effect on the corrosion rate, and the corrosion rate de-creased to a lower level when the temperature reached 90~98℃, due to the influence of corrosion product film;when the temper-ature was in the range

  9. Construction and assembly of pipelines using API 5L grade X80 tubes - considerations to be observed with high-strength steels; Construcao e montagem de dutos terrestres utilizando tubos API 5L Gr. X80

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Ailton C. de; Rabello, Jose Mauricio B. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2005-07-01

    The use of line pipes API 5L Grade X80, at the point of view of designer allows: reduction of wall thickness and pipe weight or increase of design pressure. In the pipeline construction point of view, the use of line pipes API 5L Grade X80 provide some advantages, however some difficulties must be expected in several stages of the construction and assembly. The implications in cost, productivity, inspection and integrity, with the application of these high resistance steels, complying with PETROBRAS Standard N - 464 Construcao, Montagem e Condicionamento de Dutos Terrestres (Rev. H - 2004 Dec) and the experience consolidated in pipelines construction abroad were presented. At the design stage, a comparison between pipelines designed using API 5L-X70 and API 5L-X80 was carried out approaching the aspects of variation of thickness, pressure design and design factor. An evaluation of the expected gains when choosing API 5L Grade X80 steels were done, regarding reduction of costs and pipe weight. Regarding API 5L-X80 pipe fabrication, the obtained results were reported, proving that this aspect was already overcome, showing the viability of its production in Brazil. Difficulties were detected regarding construction and assembly stage and showing the need of revision of PETROBRAS standard N-464. (author)

  10. Ferrite transformation kinetics of X70 pipeline steel during continuous cooling%连续冷却过程中 X70管线钢的铁素体相变动力学

    Institute of Scientific and Technical Information of China (English)

    谢保盛; 蔡庆伍; 余伟; 曹嘉明; 杨云峰

    2014-01-01

    Thermal expansion curves of X 70 pipeline steel during continuous cooling process were tested on DIL 805 dilatometer .Based on experimental results , the start temperature of austenite to ferrite transformation among two models were analyzed , and the key parameters of ferrite transformation were obtained by reverse regression method with the JMAK equation , thus the kinetics during continuous cooling process were determined.The results show that, the optimal n and k can be obtained by the method mentioned above .In models, n is set as 0.5, 1, 1.5, 1-0.5X2 respectively to calculate the transformation kinetics , where X represents transformation volume fraction .In terms of n value characterized by 1-0.5X2 , it is higher precision and in better agreement with the experimental data than n value set as 0.5, 1, 1.5.In modelⅠ, the predicted results are deviated under high cooling rate , which results from the limitation of ferrite nucleation energy ΔGV . However , while modelⅡjust including two parameters is more availability .To X70 pipeline steel , the relationship between start temperature of ferrite transformation and cooling rate is indicated as Ts=Ae3 -39.1440φ0.4020 .%在DIL805膨胀仪上测量了X70管线钢在连续冷却过程中的热膨胀曲线。根据试验结果,分析比较了两种奥氏体-铁素体相变开始温度模型,并通过对JMAK方程采用逆向回归法确定了铁素体相变分数的关键性参数,从而确定了连续冷却过程中的相变动力学。结果表明,不同冷却速率下的最佳n值和k值可通过JKMA公式逆向回归得出,模型分别采用时间指数n为0.5、1、1.5、1-0.5X2的4种取值方法计算铁素体相变动力学曲线,通过与试验数据的对比发现,用相变体积分数X的函数表征n值的方法计算精度更高,与试验结果吻合更好。模型Ⅰ由于对铁素体体积形核功ΔGV的取值有局限性,使得模型在大冷却速率下的预测结果

  11. EDS analysis of aluminized coatings on X70 pipeline steel after salt spray corrosion%X70管线钢渗铝层盐雾腐蚀后能谱面扫描分析

    Institute of Scientific and Technical Information of China (English)

    孔德军; 吴永忠; 付贵忠; 龙丹

    2013-01-01

    利用激光热效应对X70管线钢进行渗铝处理,研究了其在5%盐雾试验中的腐蚀行为,通过SEM、EDS和XRD等手段对腐蚀产物表面-界面形貌、化学元素面扫描和物相组成进行了分析,探讨了渗铝层耐盐雾腐蚀机理.结果表明,渗铝层界面由渗铝层、扩散层和基体组成,Al和Fe原子在扩散层相互扩散,形成了FeAl2金属化合物相,是界面冶金结合的主要机制;盐雾腐蚀以点蚀为主,表面出现裂纹是热扩散过程中热应力作用的结果;腐蚀后渗铝层界面中存在Al和O元素的分层富集现象,形成的Al2O3氧化膜有效地阻止Cl-对基体金属的腐蚀,Al在渗铝层的局部富集是保护基体的主要因素,提高了X70管线钢的耐盐雾腐蚀性能.%Aluminizing treatment was conducted on surface of a X70 pipeline steel with laser thermal effect,and corrosion behavior of the aluminized coatings in 5% salt spray test was investigated.The surface-interface morphology,microstructure and phase component of the coatings were analyzed by means of SEM,EDS and XRD.The mechanism of salt spray corrosion of the aluminized coatings was discussed.The results show that the aluminized coatings are composed of aluminized layer,diffusion layer and substrate.The elements of Al and Fe are diffused each other in the diffusion layer,forming a intermetallic compound phase of FeAl2,that is the main mechanism of the metallurgical binding of the interface.The pitting corrosion in the aluminized coatings is the main mode for salt spray corrosion.The surface cracking is a result of thermal stress.There is a stratified enrichment of Al and O elements in the aluminized coating interface,forming a layer of Al2O3 film to effectively prevent Cl-from eroding the substrate metals,and the Al enrichment is a main factor of protecting the substrate,improving the properties of salt spray corrosion for X70 pipeline steel.

  12. Bauschinger effect on API 5L B and X56 steel plates under repeating bending load

    Science.gov (United States)

    Chandra, Icho Y.; Korda, Akhmad A.

    2017-01-01

    During steel pipe fabrication, hot rolled coil steel will undergo coiling and uncoiling process, where the steel plate is bent repeatedly. When cyclic loading is imposed on steel, tensile and compressive stress will occur in it resulting in softening caused by Bauschinger effect. This research is focused on Bauschinger effect and cyclic loading during coiling and uncoiling process on API 5L B and API 5L X56 steel. Both types of steel were given repeated bend loading with variation in loading cycle and the curvature radius. The steel's response was then observed by using tensile testing, microhardness testing, and microstructure observation. A decrease in yield strength is observed during lower cycles and on smaller radii. After higher loading cycle, the yield strength of the steel was increased. Microhardness testing also reported similar results on the subsurface part of the steel where loading is at its highest.

  13. Fracture-Toughness Analysis in Transition-Temperature Region of Three American Petroleum Institute X70 and X80 Pipeline Steels

    Science.gov (United States)

    Shin, Sang Yong; Woo, Kuk Je; Hwang, Byoungchul; Kim, Sangho; Lee, Sunghak

    2009-04-01

    The fracture toughness in the transition-temperature region of three American Petroleum Institute (API) X70 and X80 pipeline steels was analyzed in accordance with the American Society for Testing and Materials (ASTM) E1921-05 standard test method. The elastic-plastic cleavage fracture toughness ( K Jc ) was determined by three-point bend tests, using precracked Charpy V-notch (PCVN) specimens; the measured K Jc values were then interpreted by the three-parameter Weibull distribution. The fracture-toughness test results indicated that the master curve and the 98 pct confidence curves explained the variation in the measured fracture toughness well. The reference temperatures obtained from the fracture-toughness test and index temperatures obtained from the Charpy impact test were lowest in the X70 steel rolled in the two-phase region, because this steel had smaller effective grains and the lowest volume fraction of hard phases. In this steel, few hard phases led to a higher resistance to cleavage crack initiation, and the smaller effective grain size led to a higher possibility of crack arrest, thereby resulting in the best overall fracture properties. Measured reference temperatures were then comparatively analyzed with the index temperatures obtained from the Charpy impact test, and the effects of microstructures on these temperatures were discussed.

  14. STUDY OF THE X70 PIPELINE STEEL CORRODING IN 3.0wt% NaCl SOLUTION USING ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    L.J. Zhang; Z. Zhang; F.H. Cao; J.Q. Zhang; J.M. Wang; C.N. Cao

    2004-01-01

    The corrosion process of the X70 pipeline steel in 3.0wt% NaCl solution were studied using polarization method, and the chronological characteristics during the entire polarization plot were investigated in detail using EIS technique. In the active region of X70 steel such as 20mV potential bias applied on open circuit potential (OCP), the impedance spectra was comprised of three parts: a high-frequency capacitive loop, a middle-frequency capacitive loop and a low-frequency inductive component. When positive polarization potential increased, the capacitive loops at high and middle frequency range merged, and the inductive component at low frequency shrunk. At high positive polarization potential bias (500-800mV vs. OCP), the high-frequency capacitive loop and the low-frequency inductive loop exhibited as disheveled points due to the synergism of the inhomogeneity of the corroding material and the localized corrosion. The results were fitted utilizing the equivalent circuits to simulate the impedance spectra and to interpret the electrochemical features shown during the experiments.

  15. Characterization of HAZ of API X70 Microalloyed Steel Welded by Cold-Wire Tandem Submerged Arc Welding

    Science.gov (United States)

    Mohammadijoo, Mohsen; Kenny, Stephen; Collins, Laurie; Henein, Hani; Ivey, Douglas G.

    2017-03-01

    High-strength low-carbon microalloyed steels may be adversely affected by the high-heat input and thermal cycle that they experience during tandem submerged arc welding. The heat-affected zone (HAZ), particularly the coarse-grained heat-affected zone (CGHAZ), i.e., the region adjacent to the fusion line, has been known to show lower fracture toughness compared with the rest of the steel. The deterioration in toughness of the CGHAZ is attributed to the formation of martensite-austenite (M-A) constituents, local brittle zones, and large prior austenite grains (PAG). In the present work, the influence of the addition of a cold wire at various wire feed rates in cold-wire tandem submerged arc welding, a recently developed welding process for pipeline manufacturing, on the microstructure and mechanical properties of the HAZ of a microalloyed steel has been studied. The cold wire moderates the heat input of welding by consuming the heat of the trail electrode. Macrostructural analysis showed a decrease in the CGHAZ size by addition of a cold wire. Microstructural evaluation, using both tint etching optical microscopy and scanning electron microscopy, indicated the formation of finer PAGs and less fraction of M-A constituents with refined morphology within the CGHAZ when the cold wire was fed at 25.4 cm/min. This resulted in an improvement in the HAZ impact fracture toughness. These improvements are attributed to lower actual heat introduced to the weldment and lower peak temperature in the CGHAZ by cold-wire addition. However, a faster feed rate of the cold wire at 76.2 cm/min adversely affected the toughness due to the formation of slender M-A constituents caused by the relatively faster cooling rate in the CGHAZ.

  16. SYNERGISTIC EFFECT OF TUNGSTATE AND BENZOTRIAZOLE ON CORROSION INHIBITION OF X70 STEEL%钨酸盐与苯并三唑对X70钢协同缓蚀作用的研究

    Institute of Scientific and Technical Information of China (English)

    张付宝; 余晓鹏; 潘献晓; 肖亦; 李容; 蔡铎昌

    2006-01-01

    应用动电位扫描法和电化学阻抗法研究了钨酸盐和苯并三唑(BTA)在氯化钠介质中对X70钢的协同缓蚀作用.结果表明:X70钢在0.03%的NaCl溶液中的腐蚀为混合控制过程.Na2WO4·2H2O和苯并三唑均为阳极型缓蚀剂.在保持缓蚀剂总浓度为2×10-3mol/L时,Na2WO4·2HO:BTA为1:1时缓蚀率达最大,为83.01%.

  17. Evolution of weld metal microstructure in shielded metal arc welding of X70 HSLA steel with cellulosic electrodes: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Ghomashchi, Reza, E-mail: reza.ghomashchi@adelaide.edu.au; Costin, Walter; Kurji, Rahim

    2015-09-15

    The microstructure of weld joint in X70 line pipe steel resulted from shielded metal arc welding with E6010 cellulosic electrodes is characterized using optical and electron microscopy. A range of ferritic morphologies have been identified ranging from polygonal inter- and intra-prior austenite grains allotriomorphic, idiomorphic ferrites to Widmanstätten, acicular and bainitic ferrites. Electron Backscatter Diffraction (EBSD) analysis using Image Quality (IQ) and Inverse Pole Figure (IPF) maps through superimposition of IQ and IPF maps and measurement of percentages of high and low angle grain boundaries was identified to assist in differentiation of acicular ferrite from Widmanstätten and bainitic ferrite morphologies. In addition two types of pearlitic structures were identified. There was no martensite detected in this weld structure. The morphology, size and chemistry of non-metallic inclusions are also discussed briefly. - Highlights: • Application of EBSD reveals orientation relationships in a range of phases for shielded metal arc welding of HSLA steel. • Nucleation sites of various ferrite morphologies identified • Formation of upper and lower bainite and their morphologies.

  18. Effect of CO 2 Partial Pressure on CO 2 Corrosion of X70 Steel at Multiphase Flow%多相流动状态下 CO 2分压对X70钢 CO 2腐蚀的影响

    Institute of Scientific and Technical Information of China (English)

    崔铭伟; 封子艳; 韩建红; 曹学文

    2015-01-01

    应用自制实验装置,模拟起伏管路段塞流动条件下 X70钢 CO 2腐蚀问题,通过电子显微镜、腐蚀挂片以及电化学在线监测等对挂片表面形貌、腐蚀速率以及挂片在线腐蚀情况进行分析,研究了多相流动状态下 CO 2分压对 X70钢 CO 2腐蚀速率的影响。结果表明,CO 2分压对 X70钢 CO 2腐蚀存在正反两方面的影响:随着 CO 2分压的增加,一方面腐蚀介质酸性增强,加快腐蚀;另一方面,CO 2-3的浓度升高,与 Mg2+、Ca2+、Fe2+等阳离子在腐蚀挂片表面形成了一层腐蚀产物膜,降低了腐蚀速度;CO 2分压对 X70钢 CO 2腐蚀的影响与温度息息相关,随着温度的升高,腐蚀速率达到最高值的 CO 2分压越来越低,CO 2分压对 X70钢基体的保护作用大过腐蚀作用的 CO 2分压越来越低。%The corrosion of X70 steel was simulated at plug flow using the homemade experimental apparatus.The effect of CO 2 partial pressure on CO 2 corrosion of X70 steel was studied by analysis of the bolt surface morphology,corrosion rate,and online coupon corrosion situation using electronic microscope,bolt and electrochemical corrosion online monitoring.The results showed there was two effect of the pros and cons on of CO 2 partial pressure on CO 2 corrosion of X70 steel.On the one hand, enhances of corrosive medium acidity accelerated the corrosion rate,on the other hand,CO 2-3 combined with Mg2+ ,Ca2+ and Fe2+ and a layer of corrosion product film was formed which reduced the corrosion rate when concentration of CO 2-3 increased. The effect of CO 2 partial pressure on CO 2 corrosion of X70 steel was closely related to the temperature.The CO 2 partial pressure reduced when the corrosion rate achieved the highest point and protection role was greater than corrosion role for X70 steel substrate with the increasing of temperature.

  19. CO2 corrosion morphology of X70 pipeline steel under jet impingement at high temperature and high pressure environment%高温高压喷射条件下X70管线钢的CO2腐蚀形貌

    Institute of Scientific and Technical Information of China (English)

    蔡峰; 柳伟; 樊学华; 张晶; 路民旭

    2014-01-01

    利用自主研发的高温高压环路喷射装置并结合流体动力学模拟计算,研究了高温高压CO2环境流体喷射条件下X70钢的腐蚀产物微观形貌、基体表面三维形貌、腐蚀减薄量及其统计规律,并探讨了与流体状态之间的关系。结果表明,高温高压流体喷射条件下,不同流态区域内流体传质速率和壁面切应力的差异是造成X70钢腐蚀产物、基体表面三维形貌及腐蚀减薄量差异的主要原因。按照层流区→壁面喷射区→过渡区的顺序,流体壁面切应力逐渐增加,不断减薄腐蚀产物膜直至其脱落,造成传质过程阻力减小,传质速率增大,腐蚀过程不断加剧。因此,按照层流区→壁面喷射区→过渡区的顺序,X70钢表面腐蚀产物膜由完整致密向疏松多孔变化,基体表面三维形貌呈现平坦→陡峭→非常陡峭的特征,三维表面高度偏差和均方根偏差、腐蚀减薄量平均值和标准差均呈现逐渐增大的趋势。在高温高压流体喷射条件下,X70钢的CO2腐蚀速率与壁面切应力之间较好地满足指数关系。%The CO2 corrosion behavior of X70 pipeline steel, including the corrosion product's morphology, three-dimensional sur-face topography, and corrosion thickness reduction as well as its statistical analysis, was investigated in high temperature and high pres-sure CO2 environment using self-developed loop jet impingement apparatus and computation fluid dynamic ( CFD) technique. The rela-tionship between the obtained results and flow regimes under jet impingement was also discussed. It is found that the differences of fluid mass transfer and wall shear stress distributed on the steel surface located at different flow regimes are the main reason for the differ-ences of the corrosion product's morphology, three-dimensional surface topography and corrosion thickness reduction. According to the order of the laminar zone, the wall jet zone and the transition zone, the

  20. Numerical evaluation of multipass welding temperature field in API 5L X80 steel welded joints

    Directory of Open Access Journals (Sweden)

    J Nóbrega

    2016-10-01

    Full Text Available Many are the metallurgical changes suffered by materials when subjected to welding thermal cycle, promoting a considerable influence on the welded structures thermo mechanical properties. In project phase, one alternative for evaluating the welding cycle variable, would be the employment of computational methods through simulation. So, this paper presents an evaluation of the temperature field in a multipass welding of API 5L X80 steel used for oil and gas transportation, using the ABAQUS ® software, based on Finite Elements Method (FEM. During the simulation complex phenomena are considerable including: Variation in physical and mechanical properties of materials as a function of temperature, welding speed and the different mechanisms of heat exchange with the environment (convection and radiation were used. These considerations allow a more robust mathematical modeling for the welding process. An analytical heat source proposed by Goldak, to model the heat input in order to characterize the multipass welding through the GTAW (Gas Tungsten Arc Welding process on root and the SMAW (Shielded Metal Arc Welding process for the filling passes were used. So, it was possible to evaluate the effect of each welding pass on the welded joint temperature field, through the temperature peaks and cooling rates values during the welding process.

  1. Fragilización por Hidrógeno de los Aceros API 5L X60 y API 5L X80 Hydrogen Embrittlement of API 5L X60 and API 5L X80 Steels

    OpenAIRE

    Bruno A Araújo; Jorge A Palma; Vilar, Eudésio O.; Silva, Antonio A.

    2011-01-01

    Se ha determinado el comportamiento mecánico de los aceros API 5L grados X60 y X80, fragilizados por hidrógeno ambiental y por hidrógeno interno. El potencial y la densidad de corriente para la generación del hidrógeno fueron determinados por polarización potenciodinámica, y el tiempo de saturación estimado a partir de datos de difusividad y solubilidad obtenidos en ensayos de permeación con una célula electroquímica. La carga de hidrógeno para reproducir las condiciones de la fragilización p...

  2. Building P-S-N Curves of Weld Metal of Spiral Submerge-Arc Welded X70 Steel Pipe%螺旋埋弧焊接X70钢管焊缝金属P-S-N 曲线的建立

    Institute of Scientific and Technical Information of China (English)

    郑新侠; 雒设计

    2016-01-01

    通过对螺旋埋弧焊接X70钢管焊缝金属进行疲劳试验,得到了不同应力幅和应力比下的疲劳寿命数据,对疲劳寿命的概率分布进行了分析;依据当量疲劳寿命公式,获得疲劳抗力系数和当量疲劳极限,并对其概率分布进行分析,进而建立了焊缝金属的P-S-N 曲线,给出了指定存活率下的疲劳寿命曲线。结果表明:焊缝金属的疲劳寿命服从对数正态分布,疲劳抗力系数服从对数正态分布,以当量应力表示的疲劳极限服从正态分布。%Fatigue tests were conducted on weld metal specimens cut from spiral submerge-arc welded X70 steel pipe.Fatigue life data at different stress amplitudes and stress rations were obtained.The probability distribution of these data was analyzed.Based on the equivalent fatigue life formula,values of fatigue resistant coefficient and equivalent fatigue limit were obtained and their probability distribution were also analyzed.The P-S-N curves of weld metal were built up.Fatigue life curves at given survivability were given.The results show that fatigue life of weld metal follows 1ogarithmic normal distribution,fatigue resistant coefficient follows logarithmic distribution and equivalent fatigue limit follows normal distribution.

  3. The Influence of Technological Parameters of X70 Stainless Steel Ladle Refining on the Residual Content of Non-Metallic Inclusions

    Directory of Open Access Journals (Sweden)

    Babanin A.

    2015-09-01

    Full Text Available It is demonstrated that during secondary refining at the ladle furnace the carbon content of steel and the residence time of the metal in the ladle exert a significant impact on the residual content of non-metallic inclusions (NMI in steel. Mathematical calculations showed that the dynamic forces have minor effect on the motion of small sized NMI, making it difficult to penetrate deep into the slag.

  4. Thermal Stability of Nanocrystalline Structure In X37CrMoV5-l Steel

    Directory of Open Access Journals (Sweden)

    Skołek E.

    2015-04-01

    Full Text Available The aim of the study was to investigate the thermal stability of the nanostructure produced in X37CrMoV5-1 tool steel by austempering heat treatment consisted of austenitization and isothermal quenching at the range of the bainitic transformation. The nanostructure was composed of bainitic ferrite plates of nanometric thickness separated by thin layers of retained austenite. It was revealed, that the annealing at the temperature higher than temperature of austempering led to formation of cementite precipitations. At the initial stage of annealing cementite precipitations occurred in the interfaces between ferritic bainite and austenite. With increasing temperature of annealing, the volume fraction and size of cementite precipitations also increased. Simultaneously fine spherical Fe7C3 carbides appeared. At the highest annealing temperature the large, spherical Fe7C3 carbides as well as cementite precipitates inside the ferrite grains were observed. Moreover the volume fraction of bainitic ferrite and of freshly formed martensite increased in steel as a result of retained austenite transformation during cooling down to room temperature.

  5. Evaluation of the diffusivity and susceptibility to hydrogen embrittlement of API 5L X80 steel welded joints

    Directory of Open Access Journals (Sweden)

    B Araújo

    2016-09-01

    Full Text Available This paper presents a study of susceptibility to hydrogen embrittlement of API 5L X80 steel welded joints by SMAW and GTAW processes. By varying the consumables used and the use of the same interpass temperature three different welded joints were obtained. Tests of hydrogen embrittlement susceptibility were performed according to ASTM G129-2006 with an aqueous solution (Solution A - TM0177/2005 NACE sodium thiosulfate (Na2S2O3 replacing the bubbling of H2S. From the elongation values was observed that the joint obtained in all welding conditions showed susceptibility to hydrogen embrittlement, which was determined by the elongation ratio. The joints that showed higher levels of hardness showed higher susceptibility to hydrogen embrittlement. The joints obtained with higher welding speeds for the same amount of heat input presented a reduction in the rate of hydrogen embrittlement. All joints tested in solution showed fracture surfaces with quasi cleavage zones.

  6. Corrosion rate of API 5L Gr. X60 multipurpose steel pipeline under combined effect of water and crude oil

    Science.gov (United States)

    Miao, Jian; Wang, Qiang

    2016-09-01

    Multipurpose pipeline is often seriously corroded during its service life, and the phenomenon is more prominent once the transportation medium is changed. Electrochemical polarization curves and impedance spectroscopy of the API 5L Gr. X60 steel pipeline's corrosion process in sedimentary water with different ion types and their concentrations have been studied in this work. The results showed that the corrosion rates were found to be 0.00418 and 0.00232 mm/a for pure water and crude oil, respectively. However, for the mixtures of water and crude oil (with water content increased from 0.2 vol% to 10 vol%), the corrosion rate increased consistently and reached a maximum value of 0.15557 mm/a for 10 vol% water in crude oil. The effect of the concentration of various ions, namely, chloride, bicarbonate and sulfate in (oil/water) mixtures on the corrosion rate was characterized by weight-loss method. The results showed that with increasing the ions' concentrations, the corresponding exchange current density increased significantly. The results were further supported by the observations of corrosion morphology using scanning electron microscopy and are helpful in devising guidelines which would help in reducing corrosion in multipurpose transport pipelines involving a change of transported medium during their service life.

  7. Effect of slow plastic and elastic straining on sulphide stress cracking and hydrogen embrittlement of 3. 5% Ni steel and APL 5L X60 pipeline steel

    Energy Technology Data Exchange (ETDEWEB)

    Erlings, J.G.; Groot, H.W. de; Nauta, J.

    1987-01-01

    A procedure is presented with which the roles of elastic and elastic-plastic straining in stress corrosion cracking (SCC) and hydrogen embrittlement (HE) can be determined. Premature failure of 3.5% Ni steels in sour and sweet environments due to SCC was only found when slow plastic straining was applied. With purely elastic slow straining the material remained crack-free, even in a buffered NACE solution. Depending on the sourness of the environment, the API 5L X60 pipeline material did not always need plastic straining to suffer HE cracking. Under none of the test conditions studied was hardened material susceptible to SCC or HE cracking. The non-hardened material tested was not susceptible to SCC in the various CO/sub 2/- and/or H/sub 2/S-containing media used.

  8. Obtaining and analysis of results of fatigue and corrosion-fatigue in steel API 5L X60; Obtencao e analise de resultados de fadiga e corrosao-fadiga em aco API 5L X60

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Bruno Allison [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais; Silva, Antonio Almeida; Santos, Fabio Gualberto Chagas [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2008-07-01

    The corrosion process allied to the fatigue, due to repetitive efforts of several natures, is the main responsible for the damages in pipeline and offshore structures that results in the appears of located faults, and by the way can results in leaks and financial and environmental loss. This phenomenon calls corrosion-fatigue, however, it is very complex, and mainly, in what it concerns the form as this it develops in the structure. The objective of this work is to present some results of experimental fatigue tests and corrosion-fatigue accomplished with specimen that the material originated a pipeline steel API 5L X60. The tests developed in a machine which could test until 12 specimens per time. For test of corrosion-fatigue was used a cell-of-corrosion especially projected, in this way simulated an aggressive environmental condition in a corrosion conditions. With the results of tests, was possible estimate the fatigue limits of the specimen when submitted to the repeated flexing, and compare it with evaluate corrosion-fatigue graphs, that as the literature comes moved down of the curve, in relation to the fatigue curve. (author)

  9. The Effect of Temperature and Acid Gas Loading on Corrosion Behavior of API 5L X52 Carbon Steel in Amine Unit

    Science.gov (United States)

    Javidi, M.; Lalehparvar, M. M.; Ghassemi, A.

    2016-05-01

    The effect of temperature and H2S concentration on amine corrosion of API 5L X52 carbon steel in a CO2-saturated 25 wt.% diethanolamine solution was investigated via electrochemical techniques. It was found that increase in temperature from 25 to 80 °C resulted in severe increase in corrosion rate from 0.88 to 16.24 mpy due to increase in degradation rate of amine. Also, it was concluded that increase in H2S concentration led to increase in corrosion rate because of formation of more heat stable amine salts. The effect of temperature on corrosion rate was more significant than acid gas loading.

  10. Mechanical Expanding Diameter Process of X70 JCOE Pipe%X70JCOE焊管机械扩径工艺

    Institute of Scientific and Technical Information of China (English)

    张志明; 卢胜勇; 苏景富; 苏志; 熊伟

    2011-01-01

    根据国产TMCP微合金管线钢板屈服强度(R)变化较大的现状,有针对性地对某厂X70管线钢板采用了JCO+机械扩径制造工艺,获得了对应屈服强度、抗拉强度、屈强比和冲击韧性的变化曲线,分析了不同扩径率下钢管的力学性能变化规律和微观组织对力学性能的作用机理,阐述了合理选择扩径工艺的实践作法,并给出了JCOE直缝埋弧焊管生产线X70管线钢板建议验收的下极限.%According to the bigger change of yield strength (R0.5)for China domestic TMCP microalloy pipeline steel plate, a kind of relevant manufacturing process was adopted for X70 steel plate in some factory, and the change curve of corresponding yield strength, tensile strength, yield ratio and impact toughness were obtained. It analyzed mechanical properties change role and effect mechanism of microstructure to mechanical properties, expatiated practices of reasonably selecting expanding process, and gave the ultimate limit for accepting X70 steel plate used for JCOE SAWL pipe production line.

  11. X70管线钢在CO2-3/HCO-3体系中表面膜性能研究%Properties of Surface Film on XT0 Pipeline Steel in CO2-3/HCO-3 Environment

    Institute of Scientific and Technical Information of China (English)

    胡钢; 许淳淳

    2005-01-01

    The electrochemical behavior of X70 pipeline steel in (0.5 mol· L-1 Na2CO3+1 mol· L-1 NaHCO3)solution was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used to analyze the composition and microstructure of the surface film. The results showed that there were two anodic peaks at -600 mV and -350 mV.The surface film formed at -600 mV mainly consisted of ferrous carbonates and ferrous hydroxycarbonates. It had a small reaction resistance. It was metastable and possessed poor protective property. Numerous pits and microcracks existed on the film, which could be the active paths for the initiation of stress corrosion cracking. The surface film formed at -350 mV, mainly consisted of ferric oxides. It has high reaction resistance and offered good protection for the substrate.

  12. Research and Development of X70 with an Acicular Ferrite Microstructure for West-East Pipeline Project

    Institute of Scientific and Technical Information of China (English)

    ZhengLei; GaoShan

    2004-01-01

    It is introduced in this paper that a high strength and high toughness X70 pipeline steel with an ultra-low acicular ferrite microstructure has been researched and developed at Baosteel according to the requirements of the West-East Gas Pipeline(WEGTP) project. The developed steel has higher strength, higher toughness, lower ductile-brittle transition temperature and higher dynamic tear-resistance than the conventional X70 with ferrite and pearlite microstructure. The excellent properties of the steel are benefited from ultralow carbon acicular ferrite consisting of interaction of very fine precipitated particles and high-density dislocation. And the steel has been applied on the WEGTP in China.

  13. Numerical Evaluation of Temperature Field and Residual Stresses in an API 5L X80 Steel Welded Joint Using the Finite Element Method

    Directory of Open Access Journals (Sweden)

    Jailson A. Da Nóbrega

    2016-01-01

    Full Text Available Metallic materials undergo many metallurgical changes when subjected to welding thermal cycles, and these changes have a considerable influence on the thermo-mechanical properties of welded structures. One method for evaluating the welding thermal cycle variables, while still in the project phase, would be simulation using computational methods. This paper presents an evaluation of the temperature field and residual stresses in a multipass weld of API 5L X80 steel, which is extensively used in oil and gas industry, using the Finite Element Method (FEM. In the simulation, the following complex phenomena were considered: the variation in physical and mechanical properties of the material as a function of the temperature, welding speed and convection and radiation mechanisms. Additionally, in order to characterize a multipass weld using the Gas Tungsten Arc Welding process for the root pass and the Shielded Metal Arc Welding process for the filling passes, the analytical heat source proposed by Goldak and Chakravarti was used. In addition, we were able to analyze the influence of the mesh refinement in the simulation results. The findings indicated a significant variation of about 50% in the peak temperature values. Furthermore, changes were observed in terms of the level and profile of the welded joint residual stresses when more than one welding pass was considered.

  14. Comportamiento de Laminaciones Coplanares y No Coplanares en Acero API5L X52 Simuladas mediante Elementos Finitos Behavior of Coplanar and Non-Coplanar Laminations in API5L X52 Steel Simulated by Finite Elements

    Directory of Open Access Journals (Sweden)

    Alberto Servin

    2009-01-01

    Full Text Available Se determina el comportamiento mecánico de laminaciones simples y escalonadas modeladas por elementos finitos en condiciones no lineales de esfuerzo-deformación, para comprender la secuencia de la interacción de los campos de esfuerzos en los extremos de la grietas. Se estableció una matriz de simulación variando la extensión circunferencial de las laminaciones, con espesor del tubo de 610mm de diámetro, con separación vertical y horizontal para el caso de laminaciones escalonadas. Se determino la función de distribución de esfuerzos en la región de las laminaciones en función de la presión en la grieta y en el tubo. Se estableció la presión que origina alcanzar la cedencia y resistencia ultima del material API5L X52, determinando que las laminaciones simples cuya extensión circunferencial va de 24 a 127 mm, soportan 50% más de presión de cedencia que las laminaciones escalonadas, y el 100% más de presión máxima permisible. Basados en la graficas presión versus radio de las laminaciones se concluye que las laminaciones no coplanares representan mayor riesgo de agrietamiento en una tubería.The mechanical behavior of the coplanar and non coplanar laminations by finite element using non lineal material conditions was determined, with the purpose of knowing the interaction sequence of the stress fields in the crack tips. The analysis includes a matrix simulation considering the circumferential length lamination, wall thickness of the pipe 610mm diameter, with vertical and horizontal distance for non coplanar laminations. The stress distribution in the laminations regions as a function of the internal pressures in the cracks and pipe were determined. The simulations done allowed defining the yield and the strength pressure that reach the mechanical properties of the API 5L X52. It was found that coplanar laminations with 24 at 127mm of circumferential length resist 50% more yield pressure than the non coplanar laminations and

  15. Evaluation of the susceptibility to pitting corrosion of steel api 5L x42 exposed to solutions containing chloride ions and CO{sub 2} by electrochemical noise measurements; Evaluacion de la susceptibilidad a la corrosion por picado del acero api 5l x42 expuesto a un ambiente con cloruros y CO{sub 2} mediante la tecnica de ruido electroquimico

    Energy Technology Data Exchange (ETDEWEB)

    Pena-Ballesteros, D.; Rodriguez-Vanegas, N.; Anteliz, C.; Sarmiento Klapper, H.

    2011-07-01

    The concentration of chloride ions and the partial pressure of CO{sub 2} play an important role in the degradation of low-carbon steels used for the construction of pipelines in oil and gas industry. In order to evaluate the susceptibility of carbon steel API 5L X42 to pitting corrosion electrochemical noise and linear polarization resistance measurements were carried out in aqueous solutions containing chloride ions and CO{sub 2}. The concentration of chloride ions was varied between, 10000 and 18000 ppm, and the CO{sub 2} partial pressure between 10 psi and 18 psi. Experimental results pointed out that the formation of protective layer, consisting mainly of FeCO{sub 3}, depends on the partial pressure of CO{sub 2} in the system. Nevertheless, the stability of this layer was considerably affected by increasing the concentration of chloride ions causing that localized corrosion has taken place in some areas of the surface of API 5L X42, which were detected by electrochemical noise technique. (Author) 10 refs.

  16. Effect of the welding process on the microstructure and microhardness of API 5L X80 steel welded joint used for oil transportation pipeline; Efeito do processo de soldagem sobre a microestrutura e a microdureza de juntas soldadas de aco API 5L X80 usado em tubulacoes para transporte de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Alves, R.T.P.; Albuquerque, S.F. [Universidade Federal de Campina Grande (UFCG), PB (Brazil); Maciel, T.M.; Almeida, D.M.; Santos, M.A.

    2008-07-01

    This study had as objective to evaluate the microstructure and microhardness of API 5L X80 steel welded joints, used for pipelines to transport oil and gas, using the Shield Metal Arc Welding process with pre- heating temperature of 200 deg C and 400 deg C and the AWS E8010G electrode as filler metal. For this, besides the microhardness of the welded joint, the weld metals percentiles of micro-constituents and of columnar and regenerated grains and the medium size and extension of the heat affected zone were evaluated. The percentage of acicular ferrite in weld metal ranged from 13% to 33% which generated values of microhardness from 114 HV to 309 HV. (author)

  17. Observations of damage modes as a function of microstructure during NACE TM0177-96 tensile testing of API 5L grade X60 linepipe steels

    Energy Technology Data Exchange (ETDEWEB)

    Gingell, A.D.B.; Garat, X. [IRSID (France)

    1999-11-01

    The mechanisms of sulfide stress cracking (SSC) of grade X60 Iinepipe steels produced by thermomechanical controlled processing (TMCP) have been investigated by applying acoustic emission testing to the NACE TM0177-96 method A tensile test. This method enables the interruption of the test before failure, allowing the observation of the development of subcritical damage as a function of microstructure. The results are interpreted in terms of a correlation between local failure mode and microstructural features, with cracking obeying the kinetics described by acoustic emission. Apart from the successful application of acoustic emission testing to the NACE TM0177-96 method A tensile test, this test method has also been shown to reveal Stress-Oriented Hydrogen Induced Cracking (SOHIC) in susceptible microstructure.

  18. Influence of regenerative heat treatment on structure and properties of G20CrMo2 - 5 (L20HM cast steel

    Directory of Open Access Journals (Sweden)

    G. Golański

    2008-03-01

    Full Text Available Thc papcr prcscnts rcsuSts or rcscarch on thc influence of rcgcncratic hcat treatment on thc structurc and propcrtics [hardncss. impactcncrgy or L2O11M cnst stccl. Invcstipatcd material was taken from outer fmmc of a turbinc which was scrviccd for t 67 424 hours a! thctcmpcrauirc or 535 "C and prcssurc or 12.75 MPa. In psi-operating condition ~hicnv cstigntcd cast steel was cl~aracteri~cbdy low impactcncrpy of II I ant1 hart3ncss of 139HV30. Analysis uF the irlflue~~uuel ;lustcniriz;~ti on pariimctcrs (tcrnpcr;lturc and lime has rcvealcd rhntat thc tcinpcr;~turcr angc o f 895 + 955 "C (i-e. h3 - +I IO + 70 "C.fo r both 3 and 5 hours of holtl timc. rhc ohtaincd grain sizc amounls to 20+ 2511m. I has hccn pmved that tempcred bainitic-rcrri~ica nd remit ic-hainiric-pearlit ic stn~cturco f thc invcstigatcd cast stccl msurcs highimpact cncrgy, i.c. KV > 1001. as well a5 hardncss. i.e. 11Y30. just at thc tcrnpcmturc of OXl "C. 'I'crnpcmliirc or 7110 "C causcs i'~tnhcrincrclrsc of impact cncrgy along with a slight dccrcasc of hardncss. Morcovcr. it has hccn concludd that nppl ying oS under-annealinginstcad or tcmpcring. nflcr standardizalion. guarantees scquircd impact cncrgy of KY r 271.

  19. Research on the Non-metallic Inclusion in X70 Pipeline Cast Slab%X70管线钢铸坯中非金属夹杂物的研究

    Institute of Scientific and Technical Information of China (English)

    吴雨晨; 李俊国; 闫小林; 李守章; 曾亚南

    2009-01-01

    利用大样电解、金相观测、扫描电镜(SEM)和电子探针(EPMA)等手段,对X70管线钢铸坯中夹杂物的数量、粒径、形貌及组分进行了研究.结果表明:X70管线钢铸坯中夹杂物数量较多,粒径较大,且多为复合夹杂.针对大型夹杂物中硫化物、氧化物、硅铝酸盐和钙铝酸盐复合夹杂的特点,分析了铸坯中夹杂物的主要来源.%Utilizing the methods of sample-electrolysing, metallographic observation, SEM and EPMA, the quantity, dimension, morphologies and composition of non-metallic inclusions in X70 pipeline steel cast slab were investigated. It was suggested that there were larger amount of inclusions with larger diam-eter in the cast slab. Most of these inclusions were complex, such as sulfide, oxide, silicon aluminates and calcium aluminates inclusions. According to the characteristics of inclusions in the east slab, the ma-jor sources of different inclusions were analyzed and explored.

  20. X70M大壁厚螺旋埋弧焊管丁字焊缝工艺性能研究%Investigation on the Technological Properties of X70M Thick Wall SAWH Pipe T-shape Weld

    Institute of Scientific and Technical Information of China (English)

    蒋永峰; 王伟; 冯宗泽; 陆建刚; 任超

    2016-01-01

    X70M大壁厚螺旋埋弧焊管丁字焊缝焊接接头强度过高,经过成型器反变形易产生层状撕裂,焊缝热影响区温度过高易使焊缝组织产生脆化现象,为了确保X70M大壁厚螺旋埋弧焊管丁字焊缝焊接接头的各项性能指标,采用H08D焊丝与SJ101G焊剂匹配进行工艺试验,焊接过程中严格控制层间温度、减小焊接热输入及焊后热处理形式,通过试验得出了合理的焊接工艺。试验结果表明,按该工艺所焊试件的各项性能指标均达到API SPEC 5L PSL2标准及客户技术条件,采用此工艺已成功地生产了数万吨尼日利亚输油管线用管,效果良好。%If the welded joint strength of X70M thick wall SAWH pipe is too high, it is easy to generate backward deformation and lamellar tearing when pass through the forming machine, embrittlement phenomenon easily happen caused by too high HAZ temperature. In order to ensure the performance index of X70M thick wall SAWH pipe T-shape weld welded joints, using H08D welding wire matching with SJ101G flux to carry out process test, during the welding process strictly controlled interpass temperature, reduced the welding heat input and the form of heat treatment after welding, the reasonable welding process was obtained through experiments. The test result showed that all performance indexes of specimen by adopting the above process reach the standard API SPEC 5L PSL2 and customer technical conditions, it successfully produced tens of thousands of oil pipeline in Nigeria by adopting this technology, and the effect is good.

  1. Study of the sulphide stress corrosion cracking (SSCC) resistance of API SL GR B and X60 pipeline steels. Evaluacion de la resistencia al agrietamiento por corrosion-tension en medios sulfhidricos (SSCC) de aceros para tuberias Calidad API 5L Grados B y X60

    Energy Technology Data Exchange (ETDEWEB)

    Bao-Iturbe, C. (Babcock and Wilcox Espaola. S.A. Bilbao (Spain)); Gutierrez de Saiz-Solabarria (Univ. Pais Vasco. Departamento Ingenieria Metalurgica y Control de Materiales. Bilbao (Spain))

    1993-01-01

    A study of the sulphide stress corrosion cracking resistance at room temperature of API 5L Cr B and X60 pipeline steels has been carried out. The theoretical mechanisms in order to explain these phenomena and several operational failures of pipeline steel due to SSCC have been reviewed and the National Association of Corrosion Engineers (NACE) standard concerning SSCC has been described. The main factors of influence of the SSCC have been analysed, results are presented and conclusions are elaborated. (Author) 32 ref.

  2. Avaliação da microestrutura e propriedades mecânicas de metais de solda obtidos por processos de soldagem manual e automatizado utilizado na soldagem de aço API 5L X80 Evaluation of microstructure and mechanical properties of weld metals obtained by manual and automated welding process used in the welding of API 5L X80 steel

    Directory of Open Access Journals (Sweden)

    Siderley Fernandes Albuquerque

    2011-12-01

    Full Text Available O objetivo do trabalho foi avaliar as características da zona termicamente afetada (ZTA e a microestrutura e propriedades mecânicas de metais de solda de juntas soldadas do aço API 5L X80, obtidos para quatro diferentes procedimentos de soldagem utilizando processos manuais e automatizados. Para isto, chapas do referido aço foram soldadas por processo manual ao Arco Elétrico com Eletrodo Revestido (SMAW, utilizando 473 e 673 K como temperaturas de interpasses e o eletrodo celulósico AWS E8010-G como consumível; por processo ao Arco Elétrico com Arame Tubular (FCAW robotizado, utilizando o arame AWS E71T- 1C como metal de adição e argônio com 25%CO2 como gás de proteção; por processo a Arco Elétrico com Eletrodo de Tungstênio (GTAW mecanizado na raiz da solda, usando o arame ER70S-3 e argônio como gás de proteção. As análises microestruturais foram relacionadas com os resultados de ensaios de impacto Charpy nos metais de solda e com os perfis de microdureza Vickers ao longo da junta soldada. Os resultados indicaram maiores percentuais de Ferrita Acicular e maiores valores de resistência ao impacto nos metais de solda e uma menor extensão e granulometria da ZTA, associado ao procedimento de soldagem utilizando processo automatizado com maior velocidade de soldagem.The objective of this work was to evaluate the heat affected zone characteristics and weld metals microstructure and mechanical properties of API 5L X80 steel welded joints, obtained for four different welding procedures using manual and automated processes. For this, plates of this steel were welded by manual Shielded Metal Arc Welding (SMAW process with interpasses temperatures of 473 e 673 K, and using AWS E8010-G electrode as filler metals; robotized Flux Cored Arc Welding (FCAW process, using AWS E71T-1C wire and Ar25%CO2 as consumable and mechanized Gas Tungsten Arc Welding (GTAW process, for the root pass using AWS ER70S-3 and Ar as consumable .The

  3. Influence of cooling conditions on X70 pipeline steel in-service welding HAZ

    Institute of Scientific and Technical Information of China (English)

    Jin Haicheng; Wang Yong; Han Bin; Chen Yuhua

    2006-01-01

    The chamber device was designed and set up to simulate the in-service welding. The results show: the ts/5, t8/3 and inner wall peak temperature Tp decrease with the cooling rate increases. The welding energy is carried off by flowing medium,the cooling rate increases, and many unbalanced microstructures such as granular bainite, martensite and M-A generate; it worsens the properties of HAZ. Under air-cooling, the cooling rate is slow, the austenite grain grows obviously , the lath ferrite crosses the whole austenite, and it causes the hardness value is also big. The change of HAZ width is not obvious with the increase of cooling rate; and burn-through is not susceptible to the cooling rate. The quench microstructures increase and the hydrogen does not outflow from the HAZ easily when increase the cooling rate, so the susceptibility of hydrogen cracking increases.

  4. Hydrogen embrittlement susceptibility of a weld simulated X70 heat affected zone under H{sub 2} pressure

    Energy Technology Data Exchange (ETDEWEB)

    Alvaro, A., E-mail: antonio.alvaro@ntnu.no [Department of Engineering Design and Materials, NTNU, 7456 Trondheim (Norway); Olden, V. [SINTEF Materials and Chemistry, 7456 Trondheim (Norway); Macadre, A. [Kyushu University, WPI-I2CNER (World Premier Institute – International Institute for Carbon Neutral Energy Research) (Japan); Akselsen, Odd Magne [Department of Engineering Design and Materials, NTNU, 7456 Trondheim (Norway); SINTEF Materials and Chemistry, 7456 Trondheim (Norway)

    2014-03-01

    The present paper deals with hydrogen embrittlement (HE) susceptibility of a weld thermal simulated heat affected zone of X70 structural steel in high pressure hydrogen gas at 20 °C. Fracture mechanics Single Edge Notched Tension tests at various hydrogen pressures (0.1, 0.6, 10 and 40 MPa H{sub 2}) have been carried out. The HE susceptibility was quantified through the measurement of the fracture toughness K{sub Q} and J (the effect of hydrogen pressure was addressed through linear load increase conditions till failure was obtained). The results show that hydrogen causes a strong decrease in the fracture toughness with increasing hydrogen pressure. The critical hydrogen pressure for the onset of HE was observed to fall between 0.1 MPa and 0.6 MPa. These results were supported by Scanning Electron Microscope (SEM) investigations of the fracture surfaces which showed a clear shift in the fracture mode at 0.6 MPa H{sub 2}. Moreover, constant load tests were carried out in order to investigate the influence of hydrogen exposure time. The results imply that fracture always occurs within 8 h and that longer time to failure is related to stronger toughness reduction. This effect is more pronounced for test at 40 MPa than at 0.6 MPa hydrogen pressure levels. 3D Finite Element calculations of hydrogen diffusion have been performed and the results are discussed in relation to the experiments, in order to attempt to identify the hydrogen populations (diffusible or trapped) which act predominantly on the embrittlement of the material.

  5. THE DEVELOPMENT OF X70 ORE SLURRY PIPELINE WITH HIGH FREQUENCY RESISTANCE WELDING IN BAOSTEEL%宝钢X70矿浆输送高频焊接管线管的开发

    Institute of Scientific and Technical Information of China (English)

    沈建兰; 邢新; 张备

    2013-01-01

    宝钢φ610HFW机组于2008年初首次成功拓展了φ508 mm外径的X70高钢级管线管.2011年批量承接矿浆输送用X70出口管线工程.基于宝钢高频电阻焊X70管线产品一贯制生产工艺的设计和开发,以及对以往试制工艺的改进,成功生产和交付出高品质HFW焊管产品,为宝钢生产高钢级矿浆输送用管线管产品工艺和性能的优化奠定良好基础.

  6. Marine Structural Steel Toughness Data Bank. Volume 3

    Science.gov (United States)

    1991-08-28

    A A588 GR A K11430 1-12 A588 Gr B A588 Gr B K12043 1-12 A588 Gr C A588 Gr C K11538 1-12 A537-A A537 Gr A K02400 1-13 API 5L Gr X60 1-14 A656-70 A656...steel A710 and HSLA 80 containing primarily Cu, Ni, Cr and Mo; " Medium to high strength low alloy steels A537, CG-537, A656, A737, ABS-EH36, and API ... API 5L Gr X70 1-5 HSLA 80 1-6 ABS-EH36 A131 Gr EH36 K11852 1-7 A514E A514 Gr E K21604 1-8 A36 A36 1-9 BS 4360 Gr 50D 1-10 HY100 -K32045 1-11 A588-81 Gr

  7. Microstructure and mechanical properties of two API steels for iron ore pipelines.

    OpenAIRE

    Godefroid,Leonardo Barbosa; Cândido,Luiz Cláudio; Toffolo,Rodrigo Vicente Bayão; Barbosa,Luiz Henrique Soares

    2014-01-01

    This research compares the mechanical behavior of two API steels (X60 and X70) used in the longest pipeline in the world for the conveyance of iron ore. Tensile tests, Charpy impact tests, CTOD tests and fatigue crack growth tests are performed at ambient temperature. Metallographic examination showed a banded microstructure consisting of polygonal ferrite and pearlite in both steels, with smaller grain size and the presence of a small quantity of bainite in the X70 steel. All the mechanical ...

  8. Marine Structural Steel Toughness Data Bank (Abridged Edition)

    Science.gov (United States)

    1990-08-31

    A588 Gr B K12043 1-12 A588 Gr C A588 Gr C K11538 1-12 A537-A A537 Gr A K02400 1-13 API 5L Gr X60 1-14 A656-70 A656 Gr 70 K11804 1-15 A572 Gr 50 A572...Gr 70 60 70 0.1a I 1.45 0.025 0.035 0.35 - - 0.3s A 5! S. Or X60 1.60 0.040 O.OSO 0.50 API SL Gr X70 O.IS 1.60 A16 St 36 0.23 1.20 0.80 0.040 0.050...primarily Cu, Ni, Cr and Mo; " Medium to high strength low alloy steels A537, CG-537, A656, A737, ABS-EH36, and API 5L containing primarily Mn; and

  9. Effect of Hyperbaric Chamber Gas on Transformation Texture of the API-X70 Pipeline Weld Metal

    Science.gov (United States)

    Azar, Amin S.; Østby, Erling; Akselsen, Odd M.

    2012-09-01

    The development of the texture components in the X70 weld metal under several shielding environments was investigated using the electron-backscattered diffraction (EBSD) and orientation imaging microscopy (OIM) techniques. A new method for assigning the reference direction (RD), transverse direction (TD), and normal direction (ND) was introduced based on the morphological orientation of the grains. The analyses showed that different shielding gases affect the weld metal texture and microstructure. The shielding environment with pure argon shows the highest orientational pole density values and dominant acicular ferrite microstructure. It was observed that the distribution of misorientation angle and special coincidence site lattice (CSL) grain boundaries play significant roles in determining the tensile characteristics of the weld samples. Moreover, the bainite lattice orientation was found dependent on the directional heat flow unlike the other detected constituents.

  10. 西气东输X-70大口径钢管的研制与开发

    Institute of Scientific and Technical Information of China (English)

    王晓香

    2004-01-01

    为了保证西气东输工程成套设备国产化目标的实现,华北石油钢管厂进行了西气东输钢管制造技术和装备的开发。在满足西气东输工程对干线钢管技术要求的前提下,研制了大口径X-70螺旋埋弧焊管和大口径直缝埋弧焊管。研制中采用了精确成型和管端扩径、管端焊缝自动打磨技术以及大直缝钢管渐进式JCO成型技术等先进技术。西气东输钢管国产化的成功在国际上也产生了极大影响,显示了我国大口径输送钢管的制造能力和技术水平。

  11. Hydrogen-related stress corrosion cracking in line pipe steel

    DEFF Research Database (Denmark)

    Nielsen, Lars Vendelbo

    1997-01-01

    A correlation between hydrogen concentration (C0) and the critical stress intensity factor for propagation of hydrogen-related cracks has been established by fracture mechanical testing of CT-specimens for the heat affected zone of an X-70 pipeline steel. This has been compared with field...

  12. Elevated temperature mechanical properties of line pipe steels

    Science.gov (United States)

    Jacobs, Taylor Roth

    The effects of test temperature on the tensile properties of four line pipe steels were evaluated. The four materials include a ferrite-pearlite line pipe steel with a yield strength specification of 359 MPa (52 ksi) and three 485 MPa (70 ksi) yield strength acicular ferrite line pipe steels. Deformation behavior, ductility, strength, strain hardening rate, strain rate sensitivity, and fracture behavior were characterized at room temperature and in the temperature range of 200--350 °C, the potential operating range for steels used in oil production by the steam assisted gravity drainage process. Elevated temperature tensile testing was conducted on commercially produced as-received plates at engineering strain rates of 1.67 x 10 -4, 8.33 x 10-4, and 1.67 x 10-3 s-1. The acicular ferrite (X70) line pipe steels were also tested at elevated temperatures after aging at 200, 275, and 350 °C for 100 h under a tensile load of 419 MPa. The presence of serrated yielding depended on temperature and strain rate, and the upper bound of the temperature range where serrated yielding was observed was independent of microstructure between the ferrite-pearlite (X52) steel and the X70 steels. Serrated yielding was observed at intermediate temperatures and continuous plastic deformation was observed at room temperature and high temperatures. All steels exhibited a minimum in ductility as a function of temperature at testing conditions where serrated yielding was observed. At the higher temperatures (>275 °C) the X52 steel exhibited an increase in ductility with an increase in temperature and the X70 steels exhibited a maximum in ductility as a function of temperature. All steels exhibited a maximum in flow strength and average strain hardening rate as a function of temperature. The X52 steel exhibited maxima in flow strength and average strain hardening rate at lower temperatures than observed for the X70 steels. For all steels, the temperature where the maximum in both flow

  13. Numerical Study of Hydrogen Trapping: Application to an API 5L X60 Steel

    OpenAIRE

    Patricia Castaño-Rivera; Ramunni, Viviana P.; Pablo Bruzzoni

    2012-01-01

    A numerical finite difference method is developed here to solve the diffusion equation for hydrogen in presence of trapping sites. A feature of our software is that an optimization of diffusion and trapping parameters is achieved via a non linear least squares fit. On the other hand, we have demonstrated that usual electrochemical hydrogen permeation tests are enough to assess hydrogen free energies of trapping in the range of −35 kJ/mol to −70 kJ/mol. These conclusions are obtained by assumi...

  14. API 5L X80 PSL2 pipes manufactured by ERW process: TenarisConfab and USIMINAS development; Tubos API 5L X80 PSL2 processados por ERW: desenvolvimento TenarisConfab-Usiminas

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Ronaldo C.; Roza, Juliana E.; Kojima, Sergio S. [TenarisConfab, Pindamonhangaba, SP (Brazil); Miranda, Lucio S.; Turani, Leonardo O. [USIMINAS, Ipatinga, MG (Brazil)

    2005-07-01

    The utilization of high strength steels can decrease, both, installation and operation costs of a new pipeline, since the increase of mechanical resistance can reduce the pipe wall thickness and, consequently, the weight of the pipe. For this purpose, the manufacture of electric resistance welding (ERW) pipes is recent, and it comes as an opportunity for gas pipelines, mainly onshore projects. As a function of their larger productivity, ERW pipes are more economically attractive than those produced by seamless and SAW processes. TenarisConfab and USIMINAS, through studies and investments in manufacturing processes, have been working to increase their skills, in order to supply ERW pipes in API 5L X80 PSL2 steel. The steel elaborated by USIMINAS is low C, high Mn, Nb, V and Ti microalloyed, and with additions of Cr and Mo, aiming to produce hot rolled coils with acicular microstructure, achieved as a combination between its chemical composition and higher cooling rates after hot rolling. The results in {phi}18''(457 mm) x 0,469''(11,91 mm) pipes are presented in this article. High toughness values reached at very low temperatures suggest that ERW API 5L X80 PSL2 pipes developed by TenarisConfab and USIMINAS may be an excellent option of choice for onshore projects that request pipes in diameters up to 20''(508 mm) and thickness up to 0,500'' (12,7 mm). (author)

  15. Induction bending of API 5L X80 pipes; Curvamento a quente de tubos API 5L X80

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Gilmar Z. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)]. E-mail: g.zacca@petrobras.com.br; Naschpitz, Leonardo [Primus Processamento de Tubos S.A. - PROTUBO, Campo Grande, RJ (Brazil)]. E-mail: naschpitz@protubo.com.br

    2005-07-01

    The present work is a part of an extensive program to make possible the application of API 5L X80 in pipeline construction in Brazil. At this stage, the effect of the induction bending process on the microstructure and mechanical properties of the pipe is presented. For this study an API 5L X80 pipe, made by the UOE process, is used. The pipe was manufactured from a plate produced by thermo-mechanically controlled rolling without accelerated cooling. The pipe bending was carried out applying a local induction heating following by water quenching. The bend section, outer and inner curvature regions, of the pipe bend were evaluated and compared with the original pipe. The longitudinal weld and transition zones were not evaluated at this stage. Dimensional analyses, microstructural evaluation, Charpy-V impact tests, and tensile tests were performed. A significant microstructural change was verified in the bend area. The yield strength of the pipe bend was found to be lower than original pipe and standard requirements. Other tensile properties and impact properties are compatible with API 5L X80 requirements. (author)

  16. The Study on Fatigue Experiment and Reliability Life of Submarine Pipeline Steel

    Directory of Open Access Journals (Sweden)

    Yan Yifei

    2013-02-01

    Full Text Available The aim of the fatigue experiment study is to solve the fatigue fracture problem of X70 submarine tubing when it is under the scouring effect of offshore current. The multilevel fatigue experiments are carried out following the internation (GB4337-84 recommended method. The standard round bar fatigue specimen was made by the material of submarine pipeline steel. The fatigue life of submarine pipeline steel in different survival probability and P-S-N curve were achieved. According to reliability numerical analysis method, the reliability fatigue life of pipeline steel in different stress level is got. The results show that the fatigue life of X70 submarine pipeline steel obeys the normal distribution. The detection of submarine pipeline scouring condation should be enhanced and the pipeline zone which was scoured seriously should be repaired and controlled effectively in order to reduce the scouring effect of ocean current.

  17. Comportamiento a la Corrosión del Acero API X70 Soldado por el Proceso de Doble Arco Sumergido Inmerso en Diferentes Medios Corrosivos

    Directory of Open Access Journals (Sweden)

    Omar Francisco Montes

    Full Text Available Resumen Los aceros API X70 son aplicados en fabricación y construcción de tuberías para el transporte de hidrocarburos, sin embargo, a un lapso de tiempo se degradan debido al medio ambiente al cual están expuestos; influyendo en la velocidad y tipo de corrosión sobre las superficies del metal base (MB, zona afectada por el calor (ZAC y zona de fusión (ZF. A fin de conocer y evaluar la susceptibilidad a la corrosión en uniones del acero API X70 sometido a diferentes medios corrosivos, varias pruebas se llevaron a cabo por el proceso de soldadura de doble arco sumergido (DSAW, por sus siglas en inglés, las cuales fueron inmersas en diferentes electrolitos: Cloruro de Sodio (NaCl al 3,5% y Agua (H2O a temperatura ambiente para conocer su comportamiento. Se utilizaron técnicas electroquímicas de ruido electroquímico (RE y curvas de polarización cíclica (CPC para obtener velocidad y tipo de corrosión producida en cada una de las muestras analizadas, incluyendo las tres zonas: MB, ZAC y ZF. Además, se utilizaron técnicas de caracterización como microscopía óptica (MO y microscopía electrónica de barrido (MEB para el análisis superficial. La mayoría de las soldaduras presentan corrosión mixta, con mayores velocidades de corrosión en 3,5% de NaCl.

  18. The Study on Fatigue Experiment and Reliability Life of Submarine Pipeline Steel

    OpenAIRE

    Yan Yifei; Shao Bing; Liu Jinkun; Cheng Lufeng

    2013-01-01

    The aim of the fatigue experiment study is to solve the fatigue fracture problem of X70 submarine tubing when it is under the scouring effect of offshore current. The multilevel fatigue experiments are carried out following the internation (GB4337-84) recommended method. The standard round bar fatigue specimen was made by the material of submarine pipeline steel. The fatigue life of submarine pipeline steel in different survival probability and P-S-N curve were achieved. According to reliabil...

  19. Uma breve revisão histórica do desenvolvimento da soldagem dos aços API para tubulações A brief history review of development on API steels welding for pipeline

    Directory of Open Access Journals (Sweden)

    Jaime Casanova Soeiro Junior

    2013-06-01

    Full Text Available Este trabalho enfoca o desenvolvimento dos aços API para tubulações desde o aço API 5L X42, desenvolvido em 1948, através de laminação a quente seguida de tratamento térmico. Desde então foram feitos diferentes desenvolvimentos visando aumentar a resistência mecânica e a tenacidade, além de melhorar a soldabilidade. Entre eles, a adição de elementos de liga, produzindo os aços ARBL e a utilização de rotas de processamento termomecânico durante a laminação. Inicialmente a rota utilizada era a laminação a quente controlada (TMCR, com utilização de elemento microligante como Nb para os aços X60 e o conjunto Nb e V para os aços X65 e X70, associado a uma redução do teor de carbono. Posteriormente foi implantada a rota de fabricação do aço por laminação controlada seguida de resfriamento controlado (TMCP, com redução de carbono e adição de Nb e Ti para os aços X80, e adições de Mo, Nb, Be Ti para os X100. A redução do carbono foi motivada também para melhorar a sua soldabilidade e, por este motivo, estes aços são soldados por diferentes processos de soldagem, como o eletrodo revestido. Desenvolvimentos recentes com raiz feita com MAG-TC e enchimento com arame tubular tem dado resultados animadores.This paper is a brief history on the development of pipelines steels since the API 5L X42 steel, developed in 1948 by hot rolling followed by heat treatment. Subsequently different developments were made to increase the strength and toughness of these materials, and to improve their weldability. Among them, the addition of microalloying elements, producing HSLA steels and thermomechanical processing routes during hot rolling. Initially the route used was the controlled hot rolling (TMCR, together with microalloying element such as Nb for X60 steel and Nb plus V for X65 and X70 steels, associated with a reduction in carbon content. Later, the thermomechanical controlled process (TMCP manufacturing route was

  20. 用薄板坯连铸连轧工艺生产北极高寒地区用API X70管线钢%Casting and Rolling of API X70 Steel for Arctic Applications in a Thin Slab Rolling Plant

    Institute of Scientific and Technical Information of China (English)

    Andrea Carboni; Alessandro Pigani; Gamal Megahed; S.K. Paul; 杨秋霜

    2007-01-01

    介绍了埃及Ezz带钢厂新近投产的由达涅利供货的技术装备.用这套灵活的薄板坯轧制(fTSR)设备生产在北极高寒地区使用的PAIX70管线钢,几炉钢水的试浇试轧结果已经证明,达涅利薄板坯连铸技术特别适合生产高强度低合金钢热轧带卷,即便是用于极为严酷的使用环境,其各项性能指标仍可超过标准规定的质量要求.

  1. Burst limit state reliability for fiber-wrapped steel pipe

    Energy Technology Data Exchange (ETDEWEB)

    Dann, Markus R. [University of Calgary (Canada); Maes, Marc A. [Blade Energy Partners Ltd. (Canada); Salama, Mamdouh M. [ConocoPhillips Company (United States)

    2010-07-01

    In the oil and gas sector, due to the increase in demand, pipeline projects are being developed in remote areas with harsh environments. High strength steel pipelines have been developed but due to their high cost and to low production capacity, the focus is now on dry fiber augmented steel technology pipelines (FAST-Pipe). The aim of this paper is to present a probabilistic mechanical burst limit state for such fiber wrapped pipelines. This model has been developed based on a large strain Cauchy stress formulation and has been used to perform a reliability comparison between an X80 pipe and an X70 FAST-Pipe. Results showed that the FAST-Pipe has more uncertainties than the high strength steel pipe and thus lower factors should be used in their design. This paper provided a probabilistic limit state model which can be used for both steel pipes and FAST-Pipe.

  2. Steel making

    CERN Document Server

    Chakrabarti, A K

    2014-01-01

    "Steel Making" is designed to give students a strong grounding in the theory and state-of-the-art practice of production of steels. This book is primarily focused to meet the needs of undergraduate metallurgical students and candidates for associate membership examinations of professional bodies (AMIIM, AMIE). Besides, for all engineering professionals working in steel plants who need to understand the basic principles of steel making, the text provides a sound introduction to the subject.Beginning with a brief introduction to the historical perspective and current status of steel making together with the reasons for obsolescence of Bessemer converter and open hearth processes, the book moves on to: elaborate the physiochemical principles involved in steel making; explain the operational principles and practices of the modern processes of primary steel making (LD converter, Q-BOP process, and electric furnace process); provide a summary of the developments in secondary refining of steels; discuss principles a...

  3. Fatigue Crack Growth on Double Butt Weld with Toe Crack of Pipelines Steel

    OpenAIRE

    HADJOUI, Féthi; Benachour, Mustapha; Benguediab,Mohamed

    2012-01-01

    The welded structures have a broad applicability (car industry, aeronautical, marine, pipelines, etc.). The welding being an assembled process, presents both advantages and disadvantages. A simple existing defect after welding can generate a catastrophic fracture. This work studies the fatigue crack growth of double butt weld with toe crack. Two types of pipeline material are studied with knowing API 5L grades X60 and X70 where tension form of loading is applied. In order to p...

  4. 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

  5. Tool steels

    DEFF Research Database (Denmark)

    Højerslev, C.

    2001-01-01

    On designing a tool steel, its composition and heat treatment parameters are chosen to provide a hardened and tempered martensitic matrix in which carbides are evenly distributed. In this condition the matrix has an optimum combination of hardness andtoughness, the primary carbides provide...... 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...

  6. Prp19 Arrests Cell Cycle via Cdc5L in Hepatocellular Carcinoma Cells

    Science.gov (United States)

    Huang, Renzheng; Xue, Ruyi; Qu, Di; Yin, Jie; Shen, Xi-Zhong

    2017-01-01

    Pre-mRNA processing factor 19 (Prp19) is involved in many cellular events including pre-mRNA processing and DNA damage response. Recently, it has been identified as a candidate oncogene in hepatocellular carcinoma (HCC). However, the role of Prp19 in tumor biology is still elusive. Here, we reported that Prp19 arrested cell cycle in HCC cells via regulating G2/M transition. Mechanistic insights revealed that silencing Prp19 inhibited the expression of cell division cycle 5-like (Cdc5L) via repressing the translation of Cdc5L mRNA and facilitating lysosome-mediated degradation of Cdc5L in HCC cells. Furthermore, we found that silencing Prp19 induced cell cycle arrest could be partially resumed by overexpressing Cdc5L. This work implied that Prp19 participated in mitotic progression and thus could be a promising therapeutic target of HCC. PMID:28387715

  7. Prp19 Arrests Cell Cycle via Cdc5L in Hepatocellular Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Renzheng Huang

    2017-04-01

    Full Text Available Pre-mRNA processing factor 19 (Prp19 is involved in many cellular events including pre-mRNA processing and DNA damage response. Recently, it has been identified as a candidate oncogene in hepatocellular carcinoma (HCC. However, the role of Prp19 in tumor biology is still elusive. Here, we reported that Prp19 arrested cell cycle in HCC cells via regulating G2/M transition. Mechanistic insights revealed that silencing Prp19 inhibited the expression of cell division cycle 5-like (Cdc5L via repressing the translation of Cdc5L mRNA and facilitating lysosome-mediated degradation of Cdc5L in HCC cells. Furthermore, we found that silencing Prp19 induced cell cycle arrest could be partially resumed by overexpressing Cdc5L. This work implied that Prp19 participated in mitotic progression and thus could be a promising therapeutic target of HCC.

  8. Bax-PGAM5L-Drp1 complex is required for intrinsic apoptosis execution.

    Science.gov (United States)

    Xu, Wenjuan; Jing, Linlin; Wang, Quanshi; Lin, Chung-Chih; Chen, Xiaoting; Diao, Jianxin; Liu, Yuanliang; Sun, Xuegang

    2015-10-06

    Intrinsic apoptosis eliminates cells with damaged DNA and cells with dysregulated expression of oncogene. PGAM5, a member of the phosphoglycerate mutase family, has two splicing variants: PGAM5L (the long form) and PGAM5S (the short form). It has been well established that PGAM5 is at the convergent point of multiple necrosis pathways. However, the role of PGAM5 in intrinsic apoptosis is still controversial. Here we report that the PGAM5L, but not PGAM5S is a prerequisite for the activation of Bax and dephosphorylation of Drp1 in arenobufagin and staurosporine induced intrinsic apoptosis. Knockdown of PGAM5L inhibits the translocation of Bax to the mitochondria and reduces mitochondrial fission. The interaction between PGAM5L and Drp1 was observed in both arenobufagin and staurosporine treated HCT116 cells, but not in HCT116 Bax(-/-) cells. Bax transfection rescues the formation of the triplex in both arenobufagin and staurosporine stimulated HCT116 Bax(-/-) cells. Arenobufagin shows remarkable anti-cancer effects both in orthotropic and heterotropic CRC models and demonstrates less toxic effects as compared with that of cisplatin. Bax-PGAM5L-Drp1 complex is detected in arenobufagin and staurosporine treated CRC cells in vitro and in arenobufagin and cisplatin treated tumor in vivo as well. In summary, our results demonstrate that Bax-PGAM5L-Drp1 complex is required for intrinsic apoptosis execution.

  9. 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

  10. Culture of human mesenchymal stem cells on microcarriers in a 5 l stirred-tank bioreactor.

    Science.gov (United States)

    Rafiq, Qasim A; Brosnan, Kathryn M; Coopman, Karen; Nienow, Alvin W; Hewitt, Christopher J

    2013-08-01

    For the first time, fully functional human mesenchymal stem cells (hMSCs) have been cultured at the litre-scale on microcarriers in a stirred-tank 5 l bioreactor, (2.5 l working volume) and were harvested via a potentially scalable detachment protocol that allowed for the successful detachment of hMSCs from the cell-microcarrier suspension. Over 12 days, the dissolved O2 concentration was >45 % of saturation and the pH between 7.2 and 6.7 giving a maximum cell density in the 5 l bioreactor of 1.7 × 10(5) cells/ml; this represents >sixfold expansion of the hMSCs, equivalent to that achievable from 65 fully-confluent T-175 flasks. During this time, the average specific O2 uptake of the cells in the 5 l bioreactor was 8.1 fmol/cell h and, in all cases, the 5 l bioreactors outperformed the equivalent 100 ml spinner-flasks run in parallel with respect to cell yields and growth rates. In addition, yield coefficients, specific growth rates and doubling times were calculated for all systems. Neither the upstream nor downstream bioprocessing unit operations had a discernible effect on cell quality with the harvested cells retaining their immunophenotypic markers, key morphological features and differentiation capacity.

  11. Large scale validation of the M5L lung CAD on heterogeneous CT datasets

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Torres, E., E-mail: Ernesto.Lopez.Torres@cern.ch, E-mail: cerello@to.infn.it [CEADEN, Havana 11300, Cuba and INFN, Sezione di Torino, Torino 10125 (Italy); Fiorina, E.; Pennazio, F.; Peroni, C. [Department of Physics, University of Torino, Torino 10125, Italy and INFN, Sezione di Torino, Torino 10125 (Italy); Saletta, M.; Cerello, P., E-mail: Ernesto.Lopez.Torres@cern.ch, E-mail: cerello@to.infn.it [INFN, Sezione di Torino, Torino 10125 (Italy); Camarlinghi, N.; Fantacci, M. E. [Department of Physics, University of Pisa, Pisa 56127, Italy and INFN, Sezione di Pisa, Pisa 56127 (Italy)

    2015-04-15

    Purpose: M5L, a fully automated computer-aided detection (CAD) system for the detection and segmentation of lung nodules in thoracic computed tomography (CT), is presented and validated on several image datasets. Methods: M5L is the combination of two independent subsystems, based on the Channeler Ant Model as a segmentation tool [lung channeler ant model (lungCAM)] and on the voxel-based neural approach. The lungCAM was upgraded with a scan equalization module and a new procedure to recover the nodules connected to other lung structures; its classification module, which makes use of a feed-forward neural network, is based of a small number of features (13), so as to minimize the risk of lacking generalization, which could be possible given the large difference between the size of the training and testing datasets, which contain 94 and 1019 CTs, respectively. The lungCAM (standalone) and M5L (combined) performance was extensively tested on 1043 CT scans from three independent datasets, including a detailed analysis of the full Lung Image Database Consortium/Image Database Resource Initiative database, which is not yet found in literature. Results: The lungCAM and M5L performance is consistent across the databases, with a sensitivity of about 70% and 80%, respectively, at eight false positive findings per scan, despite the variable annotation criteria and acquisition and reconstruction conditions. A reduced sensitivity is found for subtle nodules and ground glass opacities (GGO) structures. A comparison with other CAD systems is also presented. Conclusions: The M5L performance on a large and heterogeneous dataset is stable and satisfactory, although the development of a dedicated module for GGOs detection could further improve it, as well as an iterative optimization of the training procedure. The main aim of the present study was accomplished: M5L results do not deteriorate when increasing the dataset size, making it a candidate for supporting radiologists on large

  12. Application of EQ-5D-5L questionnaire in patients suffering from urinary incontinence.

    Science.gov (United States)

    Garcia-Gordillo, M A; Collado-Mateo, D; Olivares, P R; Adsuar, J C

    2016-09-01

    Urinary incontinence is associated with reduced quality of life and given the high prevalence of people with this condition, it could be useful to know the impact of having urinary incontinence on physical, psychological and social aspects. The Spanish value set of EQ-5D was used to assign single scores to the EQ-5D-5L health states. EQ-5D-5L is a health-related quality of life questionnaire, which allows assessing health status. The aim of this study was to provide normative values of EQ-5D-5L in a population sample with urinary incontinence. Cross-sectional study. A total of 965 people with urinary incontinence (297 men and 668 women) were included in this study. EQ-5D-5L index, VAS and health status are showed in the current study considering gender, age group, region, marital status, smoking status, net monthly incomes of household and educational level. Higher prevalence was observed in women (69.22%) compared with men (30.78%). Mean (SD) EQ-5D-5L utility index and VAS score were 0.58 (0.40) and 53.91 (22.16), respectively, for overall population. The 16.1% (155 people) reported perfect health status (11111). The utility equivalent to set values 55555 was not reported by anyone. This study provides normative values of EQ-5D-5L in a Spanish population sample with urinary incontinence. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Electrochemical characteristics of pipeline-steel with planar-defect epoxy-coating in simulated solutions of Ku'erle soil

    Institute of Scientific and Technical Information of China (English)

    Cui-wei DU; Xiao-gang LI; Wei WANG; Yi-quan SONG

    2008-01-01

    An X70 pipeline steel and a low-carbon steel with different types of coating defects were studied using corrosion tests in Ku'erle simulated soil solution contain-ing 0.6000 mol/L Cl-. Electrochemical characteristics of the X70 pipeline steel with planar-defect epoxy-coating in simulated solutions of Ku'erle soil were tested. The results show that in 0.6000 mol/L Cl- simulated solution, for low-carbon steel with coating defects (the area ratio is 4.91%), at free corrosion potential and with immersion time, the corrosion with disbond was more severe than that with a break or with break and disbond. In Ku'erle soil simulated solution, when the coating defect area ratio was increased gradually (0.39% → 1.57% → 6.28%), the corrosion of the X70 steel under coating with break was promoted gradually, and the influence of immersion time on the corrosion decreased. The influence of the immer-sion time on the corrosion was weakened when the defect area ratio increased to a certain degree.

  14. Comparative study of fracture appearance in crack tip opening angle testing of gas pipeline steels

    Energy Technology Data Exchange (ETDEWEB)

    Hashemi, S.H., E-mail: shhashemi@birjand.ac.ir [Department of Mechanical Engineering, The University of Birjand, PO Box 97175-376, Birjand (Iran, Islamic Republic of)

    2012-12-15

    The crack tip opening angle (CTOA) experiments were conducted on API X65, X70, X80 and X100 steels using a modified double cantilever beam (MDCB) geometry. The fracture surfaces of the test specimens were examined after fracture tests by optical and scanning electron microscopy. The fracture surfaces of the lower grade X65 and X70 steels had fully ductile features including classic flat and slant fracture characteristics. However, repetitive propagation and arrest of quasi-cleavage in the form of chevron arrow-head fractures was observed on the fracture surfaces of higher grade X80 and X100 steels. Interestingly, the analysis of load-displacement records from the latter steels demonstrated local ragged patterns after the test peak load, associated with the repetitive low energy quasi-cleavage mechanism. Detailed discussion on the micro-fractographs of the tested steels and comparison of the test observations with the only newly published work in this filed conclude the paper.

  15. Efecto de la corrosión por h 2 so 4 en la difusividad térmica de acero api5l-x52.

    Directory of Open Access Journals (Sweden)

    Gabriel Peña-Rodríguez

    2004-01-01

    Full Text Available In this work present a study of the effect of the H2SO4 corrosion to constant pH of 1.4 in the thermal diffusivity of API5L-X52 pipeline steel. The samples were exposed by 3, 6, 9, 12 and 15 days to the corrosive solution, in an atmosphere with relative average humidity of 57.16% and temperature of 23.6°C. The thermal diffusivity measure was carried out using the photoacoustic technique in a heat transmission configuration. Our results show a decrease of the thermal diffusivity ( a with the corrosion time, presenting a behavior that is adjusted to a logistical curve of type decreasing with a saturation limit of 52% of a initial value.

  16. Effect of Celluclast 1.5L on the Physicochemical Characterization of Gold Kiwifruit Pectin

    Directory of Open Access Journals (Sweden)

    John A. Mawson

    2011-09-01

    Full Text Available The effects of Celluclast 1.5L concentration on the physicochemical characterization of gold kiwifruit pectin was evaluated. Varying the enzyme concentration affected the pectin yield and pectin physicochemical properties. The viscosity of extracted pectin was largely dependent on the enzyme concentration. Celluclast 1.5L with medium concentration exhibited the highest viscosity. Varying the enzyme concentration also influenced the molecular weight distribution. High molecular weight (Mw pectin (1.65 × 106 g/mol was obtained when the medium concentration was used. Overall, the study clearly reflects the importance of taking into consideration the amount of cellulytic enzyme added in order to determine the final quality of pectin.

  17. Evaluation of the resistance of API 5L-X80 girth welds to sulphide stress corrosion cracking and hydrogen embrittlement

    Energy Technology Data Exchange (ETDEWEB)

    Forero, Adriana [Pontificia Universidade Catolica (PUC-Rio), Rio de Janeiro, RJ (Brazil); Ponciano, Jose A. [Universidade Federal do Rio de Janeiro (COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao em Engenharia; Bott, Ivani de S. [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), Rio de Janeiro, RJ (Brazil). Dept. de Ciencia dos Materiais e Metalurgia

    2009-07-01

    The susceptibility of pipeline steels to stress corrosion cracking (SCC) depends on a series of factors ranging from the manufacture of the steel, the pipe fabrication and the assembly of the pipeline to the type of substances to be transported. The welding procedures adopted during the production and construction of the pipelines (field welding), can modify the properties of the base metal in the heat affected zone (HAZ), potentially rendering this region susceptible to SCC. This study evaluates the resistance of girth welds, in API 5L X80 pipes, to hydrogen embrittlement and to stress corrosion cracking in the presence of sulphides. The evaluation was performed according to NACE TM0177/96, Method A, applying the criterion of fracture/no fracture, and Slow Strain Rate Tensile tests (SSRT) were undertaken using a sodium thiosulphate solution according to the ASTM G129-00 Standard. According NACE requirements, the base metal was approved. The weld metal exhibited susceptibility to SCC in the presence of sulphides, failing in a period of less than 720h. This was confirmed by SSR tensile tests, where a significant decrease in the ultimate tensile strength, the elongation and the time to fracture were observed. The mechanism of fracture was transgranular. (author)

  18. NORMATIVE VALUES OF EQ-5D-5L FOR DIABETES PATIENTS FROM SPAIN.

    Science.gov (United States)

    Collado Mateo, Daniel; García Gordillo, Miguel A; Olivares, Pedro R; Adsuar, José C

    2015-10-01

    Introducción: la diabetes es una enfermedad metabólica que puede conllevar una reducción de la calidad de vida relacionada con la salud. El EQ-5D es un cuestionario genérico de calidad de vida relacionada con la salud basado en preferencias sociales. Este cuestionario ha sido muy utilizado en pacientes con diabetes. Objetivo: el objetivo del presente artículo es informar sobre los valores normativos del cuestionario EQ-5D-5L en personas españolas con diabetes. Métodos: se utilizaron datos de la Encuesta Española de Salud (2011/2012). Un total de 1.857 personas con diabetes participaron en la encuesta. La puntuación del EQ-5D-5L se ha reflejado en función del sexo, región (incluyendo las 17 comunidades autónomas y las 2 ciudades autónomas de España), y 8 grupos de edad. Resultados: la media del índice de utilidad para toda la muestra fue de 0,742. Esta fue mejor para hombres (0,826) que para mujeres (0,673). Resultados similares se observaron en la Escala Visual Analógica. El efecto techo fue mucho mayor en hombres (44,83%) que en mujeres (24,41%). Conclusiones: el presente estudio recoge datos normativos representativos del EQ-5D-5L en España de personas con diabetes.

  19. High Nitrogen Stainless Steel

    Science.gov (United States)

    2011-07-19

    Kiev, 1993. 7. High Nitrogen Steels, edited by M. Kikuchi and Y. Mishima , Vol. 36, No. 7, Iron and Steel Institute of Japan Inernational, Tokyo...the Corrosion of Iron and Steels,” High Nitrogen Steels, edited by M. Kikuchi and Y. Mishima , Vol. 36, No. 7, Iron and Steel Institute of Japan

  20. The human CD5L/AIM-CD36 axis: A novel autophagy inducer in macrophages that modulates inflammatory responses.

    Science.gov (United States)

    Sanjurjo, Lucía; Amézaga, Núria; Aran, Gemma; Naranjo-Gómez, Mar; Arias, Lilibeth; Armengol, Carolina; Borràs, Francesc E; Sarrias, Maria-Rosa

    2015-01-01

    CD5L (CD5 molecule-like) is a secreted glycoprotein that participates in host response to bacterial infection. CD5L influences the monocyte inflammatory response to the bacterial surface molecules lipopolysaccharide (LPS) and lipoteichoic acid (LTA) by inhibiting TNF secretion. Here we studied the intracellular events that lead to macrophage TNF inhibition by human CD5L. To accomplish this goal, we performed functional analyses with human monocytic THP1 macrophages, as well as with peripheral blood monocytes. Inhibition of phosphatidylinositol 3-kinase (PtdIns3K) reversed the inhibitory effect of CD5L on TNF secretion. Among the various PtdIns3K isoforms, our results indicated that CD5L activates PtdIns3K (whose catalytic subunit is termed PIK3C3), a key modulator involved in autophagy. Further analysis revealed a concomitant enhancement of autophagy markers such as cellular LC3-II content, increased LC3 puncta, as well as LC3-LysoTracker Red colocalization. Moreover, electron microscopy showed an increased presence of cytosolic autophagosomes in THP1 macrophages overexpressing CD5L. Besides preventing TNF secretion, CD5L also inhibited IL1B and enhanced IL10 secretion. This macrophage anti-inflammatory pattern of CD5L was reverted upon silencing of autophagy protein ATG7 by siRNA transfection. Additional siRNA experiments in THP1 macrophages indicated that the induction of autophagy mechanisms by CD5L was achieved through cell-surface scavenger receptor CD36, a multiligand receptor expressed in a wide variety of cell types. Our data represent the first evidence that CD36 is involved in autophagy and point to a significant contribution of the CD5L-CD36 axis to the induction of macrophage autophagy.

  1. Correction factors for safe performance of API X65 pipeline steel

    Energy Technology Data Exchange (ETDEWEB)

    Hashemi, Sayyed H. [Department of Mechanical Engineering, the University of Birjand, P.O. Box 97175/615, Birjand (Iran, Islamic Republic of)], E-mail: shhashemi@birjand.ac.ir

    2009-08-15

    Prediction of required Charpy energy for fracture arrest is vital for safe performance of gas transportation pipelines. This is commonly estimated through failure models calibrated in the past on fracture data from combined Charpy tests and full-thickness burst experiments. Unfortunately, such pipeline failure models are unable to correctly predict the minimum arrest toughness of thermo-mechanical controlled rolled (TMCR) steels. To refine the existing failure models, different empirical adjustments have been proposed in recent years. In this paper, similar correction factors were derived from fracture information of instrumented Charpy impact tests on API X65 steel. The contribution of different fracture mechanisms of impact test specimens was determined through energy partitioning analysis. Parts of the energy contribution were correlated then to the source of uncertainty observed in similar experiments. The applied technique was similar to that of previous studies on X70 and X100 steels, and proved to be encouraging in giving consistent results compared to available test data.

  2. Microstructure and Mechanism of Strengthening of Microalloyed Pipeline Steel: Ultra-Fast Cooling (UFC) Versus Laminar Cooling (LC)

    Science.gov (United States)

    Zhao, J.; Wang, X.; Hu, W.; Kang, J.; Yuan, G.; Di, H.; Misra, R. D. K.

    2016-06-01

    A novel thermo-mechanical controlled processing (TMCP) schedule involving ultra-fast cooling (UFC) technique was used to process X70 (420 MPa) microalloyed pipeline steel with high strength-high toughness combination. A relative comparison is made between microstructure and mechanical properties between conventionally processed (CP) and ultra-fast cooled (UFC) pipeline steels, together with differences in strengthening mechanisms with respect to both types of processes. UFC-processed steel exhibited best combination of strength and good toughness compared to the CP process. The microstructure of CP pipeline steel mainly consisted of acicular ferrite (AF), bainitic ferrite (BF), and dispersed secondary martensite/austenite (M/A) constituent and a small fraction of fine quasi-polygonal ferrite. In contrast, the microstructure of UFC-processed pipeline steel was predominantly composed of finer AF, BF, and dispersed M/A constituent. The primary strengthening mechanisms in UFC pipeline steel were grain size strengthening and dislocation strengthening with strength increment of ~277 and ~151 MPa, respectively. However, the strengthening contribution in CP steel was related to grain size strengthening, dislocation strengthening, and precipitation strengthening, and the corresponding strength increments were ~212, ~149 and ~86 MPa, respectively. The decrease in strength induced by reducing Nb and Cr in UFC pipeline steel was compensated by enhancing the contribution of grain size strengthening in the UFC process. In conclusion, cooling schedule of UFC combined with LC is a promising method for processing low-cost pipeline steels.

  3. Application of Celluclast 1.5L in apple pectin extraction.

    Science.gov (United States)

    Wikiera, Agnieszka; Mika, Magdalena; Starzyńska-Janiszewska, Anna; Stodolak, Bożena

    2015-12-10

    Pectins were extracted from apple pomace with Celluclast 1.5L at a dose of 25, 50 and 75 μl per 1g of material. In obtained pectin, the galacturonic acid (GalA) content, the neutral sugars (NS) profile, the degree of methylation (DM) and acetylation (DAc), the molecular mass, protein, ash and polyphenol levels as well as antioxidant and antitumor activity were determined. The lowest dose of enzymatic preparation resulted in the yield of pectin isolation comparable with acidic treatment (15.3%). Application of higher dose caused further, almost 4% increase in polymer recovery. Enzymatically isolated pectin was characterised by larger molecular mass and contained more GalA of higher DM and DAc than polymer extracted with acid. It was also richer in protein and polyphenols, and had different NS profile, which resulted in higher antiradical activity as well as the ability to inhibit the proliferation and invasion of Caco-2 adenocarcinoma cells.

  4. 3.5L V6 EcoBoost - democratization of sustainable engine technology

    Energy Technology Data Exchange (ETDEWEB)

    Kapp, Daniel; Schamel, Andreas; Hinds, Brett; Weaver, Corey [Ford Motor Co., Dearborn, MI (United States)

    2008-07-01

    The North American automotive industry is presently facing the challenge of a recently signed energy bill increasing corporate average fuel economy standards to 35 mpg (6.7 L/km) by 2020, inclusive of cars and trucks. The passing of this bill is coincident with crude oil costs hovering in the $130USD / barrel range, retail gasoline costs in the $4USD / gallon range, and mounting evidence on CO2 emissions and global warming. Ford Motor Company has anticipated these trends, has invested in the development of fuel efficient engine technologies, and is now deploying these technologies in volume to deliver both a meaningful and sustainable response to the above challenges. Leading the deployment curve is a technology publically announced as EcoBoost, representing the application of direct fuel injection and turbocharging to an advanced gasoline engine. Ford has previously reported the fundamentals of this technology which enables a significant fuel economy improvement via engine downsizing, and a significant performance improvement via engine dynamic response. As applied to 14 and V6 engine architectures, Ford has announced plans to deploy up to 750,000 EcoBoost engines worldwide by 2013 CY, with first application in the form of a 3.5L V6 EcoBoost engine in the 2010 MY Lincoln MKS luxury sedan. This paper summaries the development of the 3.5L V6 EcoBoost engine and its associated as-installed systems. Combustion, fuel, boost, and power conversion systems are discussed in detail with emphasis on the efficiency and value of these systems which enable a singular engine design to be applied across a wide range of applications. Engine performance and fuel economy assessments are also discussed and compared to conventional gasoline engines. (orig.)

  5. The Microstructure Evolution of Dual-Phase Pipeline Steel with Plastic Deformation at Different Strain Rates

    Science.gov (United States)

    Ji, L. K.; Xu, T.; Zhang, J. M.; Wang, H. T.; Tong, M. X.; Zhu, R. H.; Zhou, G. S.

    2017-07-01

    Tensile properties of the high-deformability dual-phase ferrite-bainite X70 pipeline steel have been investigated at room temperature under the strain rates of 2.5 × 10-5, 1.25 × 10-4, 2.5 × 10-3, and 1.25 × 10-2 s-1. The microstructures at different amount of plastic deformation were examined by using scanning and transmission electron microscopy. Generally, the ductility of typical body-centered cubic steels is reduced when its stain rate increases. However, we observed a different ductility dependence on strain rates in the dual-phase X70 pipeline steel. The uniform elongation (UEL%) and elongation to fracture (EL%) at the strain rate of 2.5 × 10-3 s-1 increase about 54 and 74%, respectively, compared to those at 2.5 × 10-5 s-1. The UEL% and EL% reach to their maximum at the strain rate of 2.5 × 10-3 s-1. This phenomenon was explained by the observed grain structures and dislocation configurations. Whether or not the ductility can be enhanced with increasing strain rates depends on the competition between the homogenization of plastic deformation among the microconstituents (ultra-fine ferrite grains, relatively coarse ferrite grains as well as bainite) and the progress of cracks formed as a consequence of localized inconsistent plastic deformation.

  6. Tozaltı Ark Kaynak Yöntemi ile Birleştirilen X60, X65 ve X70 Çeliklerin Kaynak Bölgesinin Etüdü

    OpenAIRE

    Ali Akın Akay, ,; Yakup Kaya; Nizamettin Kahraman

    2013-01-01

    Bu çalışmada, petrol ve doğal gaz hatlarında kullanılan, düşük alaşımlı, ince taneli ve yüksek mukavemetli X60, X65 ve X70 çelikleri, tozaltı ark kaynak yöntemi ile iki farklı tel (S1 ve S2Mo) ve toz (LN761 ve P223) kullanılarak birleştirilmiştir. Kaynaklı birleştirmelere, öncelikle yüzey ve yüzey altı kusurların belirlenebilmesi için tahribatsız muayene yöntemlerinden gözle ve ultrasonik muayeneye teknikleri uygulanmış, sonrasında birleştirmelerin dayanımlarını belirlemek amacıyla, çekme ve ...

  7. Market challenges for steel

    Energy Technology Data Exchange (ETDEWEB)

    Lauprecht, W.E.; Bulla, W.

    1981-11-01

    Country-wise division of generation of high-alloyed steels, stainless steel and alloyed steel in Western Europe/the Western World. Review of expanding markets for alloyed steels on sectors like-oil field pipes, offshore structure gas- and oil transport in pipelines, coal conversion, nuclear energy, condenser tubes, solar energy, car industry, environmental protection and chemistry.

  8. Influencia del acabado superficial en la permeación de hidrógeno del acero API 5L-X52

    Directory of Open Access Journals (Sweden)

    Réquiz, R.

    2004-02-01

    Full Text Available The influence of surface roughness on the corrosion and hydrogen permeation behaviour was evaluated on a type API 5L-X52 steel in deaerated 0.1 M Na2SO4 at pH=2. Potentiodynamic polarization curves were employed to determine the electrochemical behaviour of the steel, while the Devanathan-Stachurski technique was used to estimate the hydrogen permeation rate. Additionally, the surface roughness profiles were obtained in order to correlate the changes in the hydrogen permeation rate with different metal surface finishings. The obtained results clearly demonstrate that when the roughness parameters have larger values, the cathodic current of hydrogen evolution increases while the hydrogen entry rate decreases. This effect can be attributed to the microstructural defects induced at the steel surface, such as dislocations, which increase the catalytic activity of the atomic hydrogen favouring its recombination. Also, these defects could allow the atomic hydrogen to remain adsorbed on the steel surface. Both effects could hinder the hydrogen diffusion into the metal since the possibility for this atom of becoming absorbed has been reduced

    En el presente trabajo de investigación se evalúa la influencia del acabado superficial, tanto en la corrosión generalizada como en la permeación de hidrógeno del acero API 5L-X52 en solución de Na2SO4 0,1M, a pH=2. El comportamiento electroquímico del acero se estudió mediante las curvas de polarización potenciodinámicas, mientras que la susceptibilidad al daño por hidrógeno se evaluó mediante la técnica de permeación de Devanathan- Stachurski. Además, se determinaron los parámetros de rugosidad a las muestras de acero con diferentes acabados superficiales, para luego correlacionarlos con los cambios en las corrientes de permeación de hidrógeno. Los resultados obtenidos demuestran, claramente, que, cuando la rugosidad superficial del acero

  9. Plasma nitriding of steels

    CERN Document Server

    Aghajani, Hossein

    2017-01-01

    This book focuses on the effect of plasma nitriding on the properties of steels. Parameters of different grades of steels are considered, such as structural and constructional steels, stainless steels and tools steels. The reader will find within the text an introduction to nitriding treatment, the basis of plasma and its roll in nitriding. The authors also address the advantages and disadvantages of plasma nitriding in comparison with other nitriding methods. .

  10. Influencia del precalentamiento en las propiedades de uniones soldadas de acero API 5L-X80 soldadas con alambre tubular autoprotegido

    Directory of Open Access Journals (Sweden)

    Cooper, R.

    2004-08-01

    Full Text Available The present work refers to the characterization of API 5L-X80 pipeline joints welded with self-shielded flux cored wire. This process was evaluated under preheating conditions, with an uniform and steady heat input. All joints were welded in flat position (IG, with the pipe turning and the torch still. Tube dimensions were 762 mm in external diameter and 16 mm in thickness. Welds were applied on single V-groove, with six weld beads, along with three levels of preheating temperatures (room temperature, 100 °C, 160 °C. These temperatures were maintained as interpass temperature. The filler metal E71T8-K6 with mechanical properties different from parent metal was used in undermatched conditions. The weld characterization is presented according to the mechanical test results of tensile strength, hardness and impact test. The mechanical tests were conducted according to API 1104, AWS and ASTM standards. API 1104 and API 51 were used as screening criteria. According to the results obtained, it was possible to remark that it is appropriate to weld API 5L-X80 steel ducts with Self-shielded Flux Cored wires, in conformance to the API standards and no preheat temperature is necessary.

    Este trabajo presenta un estudio sobre la caracterización de las propiedades mecánicas de uniones soldadas con alambre tubular autoprotegido, de acero API 5L-X80. En este sentido, se evalúa la influencia de la temperatura de precalentamiento, manteniendo el aporte de calor uniforme. Todas las uniones soldadas se realizaron en la posición plana (IG, con la antorcha fíja y la tubería girando. Se utilizó un tubo de 762 mm de diámetro exterior y 16 mm de espesor. Las soldaduras se aplicaron sobre una unión de tope con bisel en V simple, utilizando 6 pasadas, con tres niveles de temperatura de precalentamiento (ambiente, 100 °C y 160 °C. Estas temperaturas se mantuvieron como temperatura entre pasadas. El metal de aporte, del tipo E71T8-K6, se utilizó en la

  11. Tozaltı Ark Kaynak Yöntemi ile Birleştirilen X60, X65 ve X70 Çeliklerin Kaynak Bölgesinin Etüdü

    Directory of Open Access Journals (Sweden)

    Ali Akın Akay, ,

    2013-12-01

    Full Text Available Bu çalışmada, petrol ve doğal gaz hatlarında kullanılan, düşük alaşımlı, ince taneli ve yüksek mukavemetli X60, X65 ve X70 çelikleri, tozaltı ark kaynak yöntemi ile iki farklı tel (S1 ve S2Mo ve toz (LN761 ve P223 kullanılarak birleştirilmiştir. Kaynaklı birleştirmelere, öncelikle yüzey ve yüzey altı kusurların belirlenebilmesi için tahribatsız muayene yöntemlerinden gözle ve ultrasonik muayeneye teknikleri uygulanmış, sonrasında birleştirmelerin dayanımlarını belirlemek amacıyla, çekme ve eğme testi uygulanmıştır. Ayrıca numuneler üzerinde sertlik ve makroyapı çalışmaları gerçekleştirilmiştir. Kaynaklı numuneler üzerinde yapılan gözle ve ultrasonik muayene sonucunda, kaynak bölgesinde herhangi bir kaynak hatasına rastlanılmamıştır. Yapılan çekme testleri sonucunda, tüm numunelerde kopma, ana malzemeden gerçekleşmiş ve bütün bağlantı dayanımları, ana malzemelerden daha yüksek bulunmuştur. Eğme testleri sonucunda, kaynak bölgesinde herhangi bir çatlak, yırtık vb. hata görülmemiştir. Yapılan sertlik testleri sonucunda, en yüksek sertlik değerleri kaynak metalinden ölçülürken onu sırasıyla ITAB ve ana malzeme takip etmektedir. Makroyapı resimleri incelendiğinde kaynak bölgesinde çatlaklara, yırtılmalara, boşluklara, ergime/nüfuziyet azlığına, curuf kalıntılarına ve yanma oluklarına rastlanılmamıştır. Deney sonuçları genel olarak değerlendirildiğinde, X70 malzemede kullanılan, S2Mo teli ve P223 tozu en verimli mekanik test sonuçları vermiştir.

  12. Ultrahigh carbon steels, Damascus steels, and superplasticity

    Energy Technology Data Exchange (ETDEWEB)

    Sherby, O.D. [Stanford Univ., CA (United States). Dept. of Materials Science and Engineering; Wadsworth, J. [Lawrence Livermore National Lab., CA (United States)

    1997-04-01

    The processing properties of ultrahigh carbon steels (UHCSs) have been studied at Stanford University over the past twenty years. These studies have shown that such steels (1 to 2.1% C) can be made superplastic at elevated temperature and can have remarkable mechanical properties at room temperature. It was the investigation of these UHCSs that eventually brought us to study the myths, magic, and metallurgy of ancient Damascus steels, which in fact, were also ultrahigh carbon steels. These steels were made in India as castings, known as wootz, possibly as far back as the time of Alexander the Great. The best swords are believed to have been forged in Persia from Indian wootz. This paper centers on recent work on superplastic UHCSs and on their relation to Damascus steels. 32 refs., 6 figs.

  13. Calculation of the yield and tensile strength in the alloying non quenched-tempered steel by the electron structure parameters

    Institute of Scientific and Technical Information of China (English)

    LIU Zhilin; LIN Cheng; LIU Yan; GUO Yanchang

    2005-01-01

    Based on the phase transformations and strengthening mechanisms during roiling, the strength increments △σb under different strengthening mechanisms are calculated with the covalent electron number nA of the strongest bond in phase cells of alloys and the interface electron density difference △ρ matching the interface stress in alloys. The calculation method of the finishing rolling yield strength is proposed, and it is integrated with the proposed calculation formulas of strength of non quenched-tempered steel. Therefore,the general formulas to simultaneously calculate both the finishing rolling strength and the yield strength of the continuous casting-rolling and non quenched-tempered steel are given. Taken the pipeline steel X70 as an example, the predictions of properties and technological parameters are performed before production or online.

  14. Adhesions of extracellular surface-layer associated proteins in Lactobacillus M5-L and Q8-L.

    Science.gov (United States)

    Zhang, Yingchun; Xiang, Xinling; Lu, Qianhui; Zhang, Lanwei; Ma, Fang; Wang, Linlin

    2016-02-01

    Surface-layer associated proteins (SLAP) that envelop Lactobacillus paracasei ssp. paracasei M5-L and Lactobacillus casei Q8-L cell surfaces are involved in the adherence of these strain to the human intestinal cell line HT-29. To further elucidate some of the properties of these proteins, we assessed the yields and expressions of SLAP under different incubation conditions. An efficient and selective extraction of SLAP was obtained when cells of Lactobacillus were treated with 5 M LiCl at 37°C in aerobic conditions. The SLAP of Lactobacillus M5-L and Q8-L in cell extracts were visualized by SDS-PAGE and identified by Western blotting with sulfo-N-hydroxysuccinimide-biotin-labeled HT-29 cells as adhesion proteins. Atomic force microscopy contact imaging revealed that Lactobacillus strains M5-L and Q8-L normally display a smooth, homogeneous surface, whereas the surfaces of M5-L and Q8-L treated with 5 M LiCl were rough and more heterogeneous. Analysis of adhesion forces revealed that the initial adhesion forces of 1.41 and 1.28 nN obtained for normal Lactobacillus M5-L and Q8-L strains, respectively, decreased to 0.70 and 0.48 nN, respectively, following 5 M LiCl treatment. Finally, the dominant 45-kDa protein bands of Lactobacillus Q8-L and Lactobacillus M5-L were identified as elongation factor Tu and surface antigen, respectively, by liquid chromatography-tandem mass spectrometry.

  15. Quality of life profile and psychometric properties of the EQ-5D-5L in HIV/AIDS patients

    Directory of Open Access Journals (Sweden)

    Tran Bach

    2012-11-01

    Full Text Available Abstract Objectives We assessed health-related quality of life (HRQOL, its associated factors, and examined measurement properties of the EuroQol - 5 Dimensions - 5 Levels (EQ-5D-5L in HIV/AIDS patients. Methods A cross-sectional multi-site survey was conducted in 1016 patients (age: 35.4 ± 7.0 years; 63.8% male in three epicenters of Vietnam. Internal consistency reliability, convergent validity, and discriminative validity of the EQ-5D-5L and a visual analogue scale (VAS were evaluated. Tobit censored regression models were used to identify predictors of HRQOL in HIV/AIDS patients. Results The mean EQ-5D-5L single index and VAS were 0.65 (95% Confidence Interval (CI = 0.63; 0.67 and 70.3 (95% CI = 69.2; 71.5. Cronbach’s alpha of five dimensions was 0.85. EQ-5D-5L has a good convergent validity with VAS (0.73. It discriminated patients at different HIV/AIDS stages, duration of ART, and CD4 cell count. Predictors of poorer HRQOL included being female, lower education level, unemployment, alcohol and drug use, CD4 Conclusion The EQ-5D-5L has good measurement properties in HIV/AIDS patients and holds potentials for monitoring ART outcomes. Integration of HRQOL measurement using EQ-5D-5L in HIV/AIDS clinical practice could be helpful for economic evaluation of HIV/AIDS interventions.

  16. Study on (100-x)(70Li2S-30P2S5)-xLi2ZrO3 glass-ceramic electrolyte for all-solid-state lithium-ion batteries

    Science.gov (United States)

    Lu, Penghao; Ding, Fei; Xu, Zhibin; Liu, Jiaquan; Liu, Xingjiang; Xu, Qiang

    2017-07-01

    A novel glass-ceramic electrolyte of (100-x)(70Li2S-30P2S5)-xLi2ZrO3 (x = 0, 1, 2, 5) is successfully prepared by a vibratory ball-milling method and followed by a heat-treatment process. Composition of the ternary sulfide electrolyte and the heat-treatment process are optimized by physical characterizations and electrochemical measurements. The testing results show that the optimal substitution quantity of Li2ZrO3 into the Li2S-P2S5 electrolyte substrate is 1 mol %. An appropriate heat-treatment temperature of 99(70Li2S-30P2S5)-1Li2ZrO3 glass-ceramic electrolyte is 285 °C. Among the as-prepared ternary electrolyte samples, 99(70Li2S-30P2S5)-1Li2ZrO3 glass-ceramic electrolyte may exhibit the highest conductivity of 2.85 × 10-3 S cm-1 at room temperature, which is much higher than that of the 70Li2S-30P2S5 glass-ceramic electrolyte. Compared to that of the all-solid-state lithium-ion battery of LiCoO2/70Li2S-30P2S5/In-Li, discharge capacities of all-solid-state lithium-ion battery of LiCoO2/99(70Li2S-30P2S5)-1Li2ZrO3/In-Li may increase 41.0% at the 10th charge-discharge cycle and 21.9% at the 50th charge-discharge cycle, respectively. Furthermore, electrochemical impedance spectroscopy (EIS) analyses of all-solid-state lithium-ion batteries reveal that addition of Li2ZrO3 into the Li2S-P2S5 electrolyte substrate may decrease the interfacial resistance between the electrodes and solid electrolyte. The improvement of electrochemical performances of 99(70Li2S-30P2S5)-1Li2ZrO3 glass-ceramic electrolyte is ascribed to both the stable crystal structure and a high lithium-ion diffusion coefficient of Li2ZrO3.

  17. Reinforcing the Steel Sector

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    By pushing forward mergers between steel-makers, China gears up to consolidate the large but fragmented industryIn a government effort to consolidate the crowded steel industry and position it for fierce global competition, the state-

  18. Exo-Arabinanase of Penicillium chrysogenum Able To Release Arabinobiose from α-1,5-l-Arabinan

    OpenAIRE

    Sakamoto, Tatsuji; Thibault, Jean-François

    2001-01-01

    An exo-arabinanase, designated Abnx, was purified from a culture filtrate of Penicillium chrysogenum 31B by ammonium sulfate precipitation, anion-exchange chromatography, and hydrophobic chromatography. Abnx had an apparent molecular mass of 47 kDa. The enzyme released only arabinobiose from the nonreducing terminus of α-1,5-l-arabinan and showed no activity towards p-nitrophenyl-α-l-arabinofuranoside and α-1,5-l-arabinofuranobiose. Abnx is the first enzyme with this mode of action.

  19. Crystallization and preliminary crystallographic analysis of exo-α-1,5-l-arabinofuranosidase from Streptomyces avermitilis NBRC14893

    OpenAIRE

    2008-01-01

    Exo-α-1,5-l-arabinofuranosidase from S. avermitilis NBRC14893 was crystallized by the sitting-drop vapour-diffusion method. The crystals diffracted to a resolution of 2.2 Å and belonged to space group P212121.

  20. A Program of Methodological Research to Arrive at the New International EQ-5D-5L Valuation Protocol

    NARCIS (Netherlands)

    Oppe, Mark; Devlin, Nancy J.; van Hout, Ben; Krabbe, Paul F.M.; de Charro, Frank

    OBJECTIVES: To describe the research that has been undertaken by the EuroQol Group to improve current methods for health state valuation, to summarize the results of an extensive international pilot program, and to outline the key elements of the five-level EuroQol five-dimensional (EQ-5D-5L)

  1. Effect of natural aging on the microstructural regions, mechanical properties, corrosion resistance and fracture in welded joints on API5L X52 steel pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Vargas-Arista, B.; Albiter, A.; Garcia-Vazquez, F.; Mendoza-Camargo, O.; Hallen, J. M.

    2014-07-01

    A characterization study was done to analyze how microstructural regions affect the mechanical properties, corrosion and fractography of the Heat Affected Zone (HAZ), weld bead and base metal for pipe naturally aged for 21 years at 30 degree centigrade. Results showed that microstructures exhibited damage and consequently decrease in properties, resulting in over-aged due to service. SEM analysis showed that base metal presented coarse ferrite grain. Tensile test indicated that microstructures showed discontinuous yield. Higher tensile strength was obtained for weld bead, which exhibited a lower impact energy in comparison to that of HAZ and base metal associated with brittle fracture by trans-granular cleavage. The degradation of properties was associated with the coarsening of nano-carbides observed through TEM images analysis, which was confirmed by SEM fractography of tensile and impact fracture surfaces. The weld bead reached the largest void density and highest susceptibility to corrosion in H{sub 2}S media when compared to those of the HAZ and base metal. (Author)

  2. Effect of natural aging on the microstructural regions, mechanical properties, corrosion resistance and fracture in welded joints on API5L X52 steel pipeline

    Directory of Open Access Journals (Sweden)

    Vargas-Arista, Benjamín

    2014-09-01

    Full Text Available A characterization study was done to analyze how microstructural regions affect the mechanical properties, corrosion and fractography of the Heat Affected Zone (HAZ, weld bead and base metal for pipe naturally aged for 21 years at 30 °C. Results showed that microstructures exhibited damage and consequently decrease in properties, resulting in over-aged due to service. SEM analysis showed that base metal presented coarse ferrite grain. Tensile test indicated that microstructures showed discontinuous yield. Higher tensile strength was obtained for weld bead, which exhibited a lower impact energy in comparison to that of HAZ and base metal associated with brittle fracture by trans-granular cleavage. The degradation of properties was associated with the coarsening of nano-carbides observed through TEM images analysis, which was confirmed by SEM fractography of tensile and impact fracture surfaces. The weld bead reached the largest void density and highest susceptibility to corrosion in H2S media when compared to those of the HAZ and base metal.Se realizó un estudio de caracterización para analizar cómo la microestructura afecta a las propiedades mecánicas, corrosión y fractura de la zona afectada por calor (ZAC, soldadura y metal base para tubería envejecida naturalmente durante 21 años a 30 °C. Los resultados indicaron que las microestructuras presentaron daño y consecuentemente reducción en propiedades mecánicas, como consecuencia del envejecimiento por servicio. El estudio mediante MEB mostró que el metal base presenta grano ferrítico grueso. La prueba de tensión indicó que las microestructuras mostraron fluencia discontinua. La mayor resistencia a la tracción se presentó en la soldadura, la cual alcanzó menor energía de impacto en comparación con la ZAC y metal base asociado con fractura frágil por clivaje transgranular. La degradación de las propriedades está en relación con el engrosamiento de nanocarburos observados a través del análisis de imágenes por MET, lo que se confirmó mediante fractografía por MEB de superfícies de fractura bajo tensión e impacto. La soldadura alcanzó la mayor densidad de microhuecos y la mayor susceptibilidad a la corrosión en un medio conteniendo H2S que cuando se compara con la ZAC y metal base.

  3. Effect of microstructure on the low temperature toughness of high strength pipeline steels

    Institute of Scientific and Technical Information of China (English)

    Yan-ping Zeng; Peng-yu Zhu; Ke Tong

    2015-01-01

    Microstructure observations and drop-weight tear test were performed to study the microstructures and mechanical properties of two kinds of industrial X70 and two kinds of industrial X80 grade pipeline steels. The effective grain size and the fraction of high angle grain boundaries in the pipeline steels were investigated by electron backscatter diffraction analysis. It is found that the low temperature toughness of the pipeline steels depends not only on the effective grain size, but also on other microstructural factors such as martensite–austenite (MA) constituents and precipitates. The morphology and size of MA constituents significantly affect the mechanical properties of the pipeline steels. Nubby MA constituents with large size have significant negative effects on the toughness, while smaller granular MA constituents have less harmful effects. Similarly, larger Ti-rich nitrides with sharp corners have a strongly negative effect on the toughness, while fine, spherical Nb-rich carbides have a less deleterious effect. The low temperature toughness of the steels is independent of the fraction of high angle grain boundaries.

  4. Estudio del daño por hidrógeno en uniones soldadas de un acero API 5L X52

    Directory of Open Access Journals (Sweden)

    Réquiz, R.

    2008-04-01

    Full Text Available The main objective of the present investigation was to study the susceptibility to hydrogen damage on a type API 5L X52 steel welded by electrical resistance. Several techniques, such as hydrogen permeation and cathodic charging were used. The metallic material was characterized using SEM and TEM. The base metal microstructure was very similar to that one corresponding to the welded area. This microstructure was mainly comprised by ferrite and perlite, differing only in the grain size. Therefore, the susceptibility to hydrogen damage was similar in both cases. It is worth mentioning that the welded area has very small dimensions. Indeed, the fusion zone is only 5 mm wide while the heat affected zone is 1 mm wide. The hydrogen damage observed was mainly in the form of blisters, which were associated to the presence of aluminum rich inclusions. Also, it was noticed partial inclusion dissolution and some matrix attack adjacent to the inclusions.

    En la presente investigación se estudió la susceptibilidad al daño por hidrógeno en un acero API 5L X52 soldado por resistencia eléctrica. Para ello, se emplearon técnicas de permeación y de carga catódica de hidrógeno. El material fue caracterizado mediante microscopía electrónica de barrido y de transmisión. La susceptibilidad al daño por hidrógeno fue similar tanto en el metal base como en el cordón de soldadura. Este comportamiento se vincula a la microestructura homogénea constituida por perlita y ferrita, que presentan ambos, aun cuando existen diferencias en el tamaño de grano. El cordón de soldadura tenía dimensiones muy pequeñas, donde la zona de fusión y la afectada por el calor poseen espesores de 5 mm y 1 mm, respectivamente. El daño inducido por hidrógeno se presentó en forma de ampollas en la superficie del material, asociado, principalmente, a la presencia de inclusiones globulares y semiglobulares ricas en aluminio. Además, se manifestó una disoluci

  5. The steel scrap age.

    Science.gov (United States)

    Pauliuk, Stefan; Milford, Rachel L; Müller, Daniel B; Allwood, Julian M

    2013-04-02

    Steel production accounts for 25% of industrial carbon emissions. Long-term forecasts of steel demand and scrap supply are needed to develop strategies for how the steel industry could respond to industrialization and urbanization in the developing world while simultaneously reducing its environmental impact, and in particular, its carbon footprint. We developed a dynamic stock model to estimate future final demand for steel and the available scrap for 10 world regions. Based on evidence from developed countries, we assumed that per capita in-use stocks will saturate eventually. We determined the response of the entire steel cycle to stock saturation, in particular the future split between primary and secondary steel production. During the 21st century, steel demand may peak in the developed world, China, the Middle East, Latin America, and India. As China completes its industrialization, global primary steel production may peak between 2020 and 2030 and decline thereafter. We developed a capacity model to show how extensive trade of finished steel could prolong the lifetime of the Chinese steelmaking assets. Secondary steel production will more than double by 2050, and it may surpass primary production between 2050 and 2060: the late 21st century can become the steel scrap age.

  6. Acetylation of mitochondrial proteins by GCN5L1 promotes enhanced fatty acid oxidation in the heart.

    Science.gov (United States)

    Thapa, Dharendra; Zhang, Manling; Manning, Janet R; Guimarães, Danielle A; Stoner, Michael W; O'Doherty, Robert M; Shiva, Sruti; Scott, Iain

    2017-08-01

    Lysine acetylation is a reversible posttranslational modification and is particularly important in the regulation of mitochondrial metabolic enzymes. Acetylation uses acetyl-CoA derived from fuel metabolism as a cofactor, thereby linking nutrition to metabolic activity. In the present study, we investigated how mitochondrial acetylation status in the heart is controlled by food intake and how these changes affect mitochondrial metabolism. We found that there was a significant increase in cardiac mitochondrial protein acetylation in mice fed a long-term high-fat diet and that this change correlated with an increase in the abundance of the mitochondrial acetyltransferase-related protein GCN5L1. We showed that the acetylation status of several mitochondrial fatty acid oxidation enzymes (long-chain acyl-CoA dehydrogenase, short-chain acyl-CoA dehydrogenase, and hydroxyacyl-CoA dehydrogenase) and a pyruvate oxidation enzyme (pyruvate dehydrogenase) was significantly upregulated in high-fat diet-fed mice and that the increase in long-chain and short-chain acyl-CoA dehydrogenase acetylation correlated with increased enzymatic activity. Finally, we demonstrated that the acetylation of mitochondrial fatty acid oxidation proteins was decreased after GCN5L1 knockdown and that the reduced acetylation led to diminished fatty acid oxidation in cultured H9C2 cells. These data indicate that lysine acetylation promotes fatty acid oxidation in the heart and that this modification is regulated in part by the activity of GCN5L1.NEW & NOTEWORTHY Recent research has shown that acetylation of mitochondrial fatty acid oxidation enzymes has greatly contrasting effects on their activity in different tissues. Here, we provide new evidence that acetylation of cardiac mitochondrial fatty acid oxidation enzymes by GCN5L1 significantly upregulates their activity in diet-induced obese mice. Copyright © 2017 the American Physiological Society.

  7. A program of methodological research to arrive at the new international EQ-5D-5L valuation protocol.

    Science.gov (United States)

    Oppe, Mark; Devlin, Nancy J; van Hout, Ben; Krabbe, Paul F M; de Charro, Frank

    2014-06-01

    To describe the research that has been undertaken by the EuroQol Group to improve current methods for health state valuation, to summarize the results of an extensive international pilot program, and to outline the key elements of the five-level EuroQol five-dimensional (EQ-5D-5L) questionnaire valuation protocol, which is the culmination of that work. To improve on methods of health state valuation for the EQ-5D-5L questionnaire, we investigated the performance of different variants of time trade-off and discrete choice tasks in a multinational setting. We also investigated the effect of three modes of administration on health state valuation: group interviews, online self-completion, and face-to-face interviews. The research program provided the basis for the EQ-5D-5L questionnaire valuation protocol. Two different types of tasks are included to derive preferences: a newly developed composite time trade-off task and a forced-choice paired comparisons discrete choice task. Furthermore, standardized blocked designs for the selection of the states to be valued by participants were created and implemented together with all other elements of the valuation protocol in a digital aid, the EuroQol Valuation Technology, which was developed in conjunction with the protocol. The EuroQol Group has developed a standard protocol, with accompanying digital aid and interviewer training materials, that can be used to create value sets for the EQ-5D-5L questionnaire. The use of a well-described, consistent protocol across all countries enhances the comparability of value sets between countries, and allows the exploration of the influence of cultural and other factors on health state values. Copyright © 2014 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  8. Ultrahigh Carbon Steel.

    Science.gov (United States)

    1984-10-01

    Steels have been utilized to prepare compacted powders of white cast iron (2 to 3%C) which exhibit superplastic be- havior at 650 0C and which are ductile ...strength and ductility than many of these commercially-avail- able steels. In particular, austempered fine-grained UHC steels exhibit good co7,binations of... Ductility of Rapidly Solidified White Cast Irons ", Powd. Metall., 26 (1983), pp. 155-160. (29) L. E. Eiselstein, 0. A. Ruano, J. Wadsworth, and 0. D

  9. Ultrahigh Carbon Steels

    Science.gov (United States)

    Sherby, O. D.; Oyama, T.; Kum, D. W.; Walser, B.; Wadsworth, J.

    1985-06-01

    Recent studies and results on ultrahigh carbon (UHC) steels suggest that major development efforts on these steels are timely and that programs to evaluate prototype structural components should be initiated. These recent results include: the development of economical processing techniques incorporating a divorced eutectoid transformation, the improvement of room temperature strength and ductility by heat treatment, the enhancement of superplastic properties through dilute alloying with silicon, and the attainment of exceptional notch impact strength in laminated UHC steel composites manufactured through solid state bonding. The unique mechanical properties achieved in UHC steels are due to the presence of micron-size fer-rite grains and ultrafine spheroidized carbides.

  10. Ford's new 3.5 l V6 gasoline engine. Downsizing with 'EcoBoost'; Der neue 3,5-l-V6-Ottomotor von Ford. Downsizing durch 'EcoBoost'

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Gerhard; Kapp, Daniel; Schamel, Andreas; Hinds, Brett; Weaver, Corey [Ford Motor Company, Dearborn, MI (United States)

    2009-03-15

    Ford banded a new motor technology as 'EcoBoost'. It applies direct fuel injection and turbocharging to gasoline engines and provides a major improvement in fuel economy via engine downsizing, combined with improved performance. The first Ford engine with this technology is the 3.5 l V6 EcoBoost in the 2010 Lincoln MKS luxury sedan. Combustion, fuel, boost, and power conversion systems are discussed in detail with emphasis on the efficiency and value of these systems. Engine level fuel economy and performance are discussed, and compared to conventional gasoline engines. (orig.)

  11. Modern Steel Framed Schools.

    Science.gov (United States)

    American Inst. of Steel Construction, Inc., New York, NY.

    In view of the cost of structural framing for school buildings, ten steel-framed schools are examined to review the economical advantages of steel for school construction. These schools do not resemble each other in size, shape, arrangement or unit cost; some are original in concept and architecture, and others are conservative. Cost and…

  12. 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.

  13. EQ-5D-5L in the General German Population: Comparison and Evaluation of Three Yearly Cross-Section Surveys.

    Science.gov (United States)

    Huber, Manuel B; Reitmeir, Peter; Vogelmann, Martin; Leidl, Reiner

    2016-03-21

    Health-related quality of life (HRQoL) is a key measure for evaluating health status in populations. Using the recent EQ-5D-5L for measurement, this study analyzed quality of life results and their stability over consecutive population surveys. Three cross-section surveys for representative samples of the general German population from 2012, 2013, and 2014 were evaluated using the EQ-5D-5L descriptive system and valuation by the Visual Analog Scale (VAS). Aggregated sample size reached 6074. The dimension with the highest prevalence of problems was pain/discomfort (31.7%). Compared with 2012 (59.3%), the percentage of participants in the best health state increased slightly in 2013 (63.4%) and 2014 (62%). Over the 3-year period, diabetes and heart disease had the strongest negative influence on mean VAS result. The number of reported chronic diseases cumulatively reduced mean VAS. Extreme problems in one or more dimensions were stated by only 0.1%-0.2% of patients. Of the potential 247 health states with a problem score ≥ 20, only six were observed in the aggregated sample. HRQoL results were fairly stable over the 3 years, but the share of the population with no problems was not. Results from the aggregated sample may serve as updated reference values for the general German population.

  14. EQ-5D-5L in the General German Population: Comparison and Evaluation of Three Yearly Cross-Section Surveys

    Directory of Open Access Journals (Sweden)

    Manuel B. Huber

    2016-03-01

    Full Text Available Health-related quality of life (HRQoL is a key measure for evaluating health status in populations. Using the recent EQ-5D-5L for measurement, this study analyzed quality of life results and their stability over consecutive population surveys. Three cross-section surveys for representative samples of the general German population from 2012, 2013, and 2014 were evaluated using the EQ-5D-5L descriptive system and valuation by the Visual Analog Scale (VAS. Aggregated sample size reached 6074. The dimension with the highest prevalence of problems was pain/discomfort (31.7%. Compared with 2012 (59.3%, the percentage of participants in the best health state increased slightly in 2013 (63.4% and 2014 (62%. Over the 3-year period, diabetes and heart disease had the strongest negative influence on mean VAS result. The number of reported chronic diseases cumulatively reduced mean VAS. Extreme problems in one or more dimensions were stated by only 0.1%–0.2% of patients. Of the potential 247 health states with a problem score ≥20, only six were observed in the aggregated sample. HRQoL results were fairly stable over the 3 years, but the share of the population with no problems was not. Results from the aggregated sample may serve as updated reference values for the general German population.

  15. Measurement properties of the EQ-5D-5L compared to the EQ-5D-3L across eight patient groups

    DEFF Research Database (Denmark)

    Janssen, M F; Pickard, A Simon; Golicki, Dominik

    2012-01-01

    disease, respiratory disease, depression, diabetes, liver disease, personality disorders, arthritis, and stroke) and a student cohort, completed the 3L and 5L and, for most participants, also dimension-specific rating scales. The 3L and 5L were compared in terms of feasibility (missing values...

  16. Clean Production of Steel and Refractories in China's Steel Industry

    Institute of Scientific and Technical Information of China (English)

    SU Tiansen

    2002-01-01

    The paper describes the importance of clean production of steel and the relationships amongst sustaining development of steel industry, environment protection and the role of refractories in the clean production of steel. The main achievements and main shortcomings in the clean production of China' s steel industry have been reviewed together with the introduction of the policy supporting system and the future development of clean production in China' s steel industry.

  17. Steel: Price and Policy Issues

    Science.gov (United States)

    2006-08-31

    Inland Steel. He had also acquired a major Mexican producer, the integrated steel works on the Pacific coast at Lazaro Cardenas . But his major coup...Steel-Producing Countries Launch Talks on Banning Subsidies at OECD Meeting” (Dec. 20, 2002). 76 Nancy E. Kelly, “Steel Talks to Kick Off in Paris, Six

  18. Marine Structural Steel Toughness Data Bank. Volume 4

    Science.gov (United States)

    1990-08-31

    A588 GR A K11430 1-12A588 Gr B A588 Gr B K12043 1-12 A588 Gr C A588 Gr C K11538 1-12A537-A A537 Gr A K02400 1-13 API 5L Gr X60 1-14 A656-70 A656 Gr 70...and HSLA 80 containing primarily Cu, Ni, Cr and Mo; • Medium to high strength low alloy steels A537, CG-537, A656, A737, ABS-EH36, and API 5L...ASTM UNS PRIORITY NAME SPEC NUMBER HYS0 A543 Gr C(1) K31820 1-1 A710-A A710 Gr A K20747 1-2 CG A537M A537 Cl 1 K12437 1-3ABS-B A131 Gr B K02102 1-4 API

  19. A Head-to-Head Comparison of UK SF-6D and Thai and UK EQ-5D-5L Value Sets in Thai Patients with Chronic Diseases.

    Science.gov (United States)

    Sakthong, Phantipa; Munpan, Wipaporn

    2017-03-13

    Little was known about the head-to-head comparison of psychometric properties between SF-6D and EQ-5D-5L or the different value sets of EQ-5D-5L. Therefore, this study set out to compare the psychometric properties including agreement, convergent, and known-group validity between the SF-6D and the EQ-5D-5L using the real value sets from Thailand and the UK in patients with chronic diseases. 356 adults taking a medication for at least 3 months were identified from a university hospital in Bangkok, Thailand, between July 2014 and March 2015. Agreement was assessed by intraclass correlation coefficients (ICCs) and Bland-Altman plots. Convergent validity was evaluated using Spearman's rank correlation coefficients between SF-6D and EQ-5D-5L and EQ-VAS and SF-12v2. For known-groups validity, the Mann-Whitney U test and Kruskal-Wallis test were used to examine the associations between SF-6D and EQ-5D-5L and patient characteristics. Agreements between the SF-6D and the EQ-5D-5L using Thai and UK value sets were fair, with ICCs of 0.45 and 0.49, respectively. Bland-Altman plots showed that the majority of the SF-6D index scores were lower than the EQ-5D-5L index scores. Both the EQ-5D-5L value sets were more related to the EQ-VAS and physical health, while the SF-6D was more associated with mental health. Both EQ-5D-5L value sets were more sensitive than the SF-6D in discriminating patients with different levels of more known groups except for adverse drug reactions. The SF-6D and both EQ-5D-5L value sets appeared to be valid but sensitive to different outcomes in Thai patients with chronic diseases.

  20. Glass Stronger than Steel

    Science.gov (United States)

    Yarris, Lynn

    2011-03-28

    A new type of damage-tolerant metallic glass, demonstrating a strength and toughness beyond that of steel or any other known material, has been developed and tested by a collaboration of researchers from Berkeley Lab and Caltech.

  1. A comparative study on the electrochemical corrosion behavior of iron and X-65 steel in 4.0 wt % sodium chloride solution after different exposure intervals.

    Science.gov (United States)

    Sherif, El-Sayed M

    2014-07-09

    In this work, the results obtained from studying the anodic dissolution of pure iron and API X-65 5L pipeline steel after 40 min and 12 h exposure period in 4.0 wt % NaCl solutions at room temperature were reported. Potential-time, electrochemical impedance spectroscopy, potentiodynamic polarization, and chronoamperometric current-time at constant potential techniques were employed. It has been found that the iron electrode corrodes in the chloride test solutions faster than the API X-65 5L steel does under the same conditions. Increasing the exposure period for the electrodes from 40 min to 12 h showed a significant reduction in the corrosion parameters for both iron and steel in the 4.0 wt % NaCl solution. Results together confirmed clearly that the X-65 steel is superior to iron against corrosion in sodium chloride solutions.

  2. Life after Steel

    Science.gov (United States)

    Mangan, Katherine

    2013-01-01

    Bobby Curran grew up in a working-class neighborhood in Baltimore, finished high school, and followed his grandfather's steel-toed bootprints straight to Sparrows Point, a 3,000-acre sprawl of industry on the Chesapeake Bay. College was not part of the plan. A gritty but well-paying job at the RG Steel plant was Mr. Curran's ticket to a secure…

  3. Performance Steel Castings

    Science.gov (United States)

    2012-09-30

    alloys , foundry, muzzle brake, supply center, tooling, sources Notice Distribution Statement A Format Information Report created in Microsoft Word...Development of Sand Properties 103 Advanced Modeling Dataset.. 105 High Strength Low Alloy (HSLA) Steels 107 Steel Casting and Engineering Support...University, University of Northern Iowa, Non- Ferrous Founders’ Society, QuesTek, buyCASTINGS.com, Spokane Industries, Nova Precision Casting, Waukesha

  4. Articles comprising ferritic stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Rakowski, James M.

    2016-06-28

    An article of manufacture comprises a ferritic stainless steel that includes a near-surface region depleted of silicon relative to a remainder of the ferritic stainless steel. The article has a reduced tendency to form an electrically resistive silica layer including silicon derived from the steel when the article is subjected to high temperature oxidizing conditions. The ferritic stainless steel is selected from the group comprising AISI Type 430 stainless steel, AISI Type 439 stainless steel, AISI Type 441 stainless steel, AISI Type 444 stainless steel, and E-BRITE.RTM. alloy, also known as UNS 44627 stainless steel. In certain embodiments, the article of manufacture is a fuel cell interconnect for a solid oxide fuel cell.

  5. GCN5L1 modulates cross-talk between mitochondria and cell signaling to regulate FoxO1 stability and gluconeogenesis.

    Science.gov (United States)

    Wang, Lingdi; Scott, Iain; Zhu, Lu; Wu, Kaiyuan; Han, Kim; Chen, Yong; Gucek, Marjan; Sack, Michael N

    2017-09-12

    The mitochondrial enriched GCN5-like 1 (GCN5L1) protein has been shown to modulate mitochondrial protein acetylation, mitochondrial content and mitochondrial retrograde signaling. Here we show that hepatic GCN5L1 ablation reduces fasting glucose levels and blunts hepatic gluconeogenesis without affecting systemic glucose tolerance. PEPCK and G6Pase transcript levels are downregulated in hepatocytes from GCN5L1 liver specific knockout mice and their upstream regulator, FoxO1 protein levels are decreased via proteasome-dependent degradation and via reactive oxygen species mediated ERK-1/2 phosphorylation. ERK inhibition restores FoxO1, gluconeogenic enzyme expression and glucose production. Reconstitution of mitochondrial-targeted GCN5L1 blunts mitochondrial ROS, ERK activation and increases FoxO1, gluconeogenic enzyme expression and hepatocyte glucose production. We suggest that mitochondrial GCN5L1 modulates post-translational control of FoxO1, regulates gluconeogenesis and controls metabolic pathways via mitochondrial ROS mediated ERK activation. Exploring mechanisms underpinning GCN5L1 mediated ROS signaling may expand our understanding of the role of mitochondria in gluconeogenesis control.Hepatic gluconeogenesis is tightly regulated at transcriptional level and is essential for survival during prolonged fasting. Here Wang et al. show that the mitochondrial enriched GCN5-like 1 protein controls hepatic glucose production by regulating FoxO1 protein levels via proteasome-dependent degradation and, in turn, gluconeogenic gene expression.

  6. Clean steels for fusion

    Energy Technology Data Exchange (ETDEWEB)

    Gelles, D.S.

    1995-03-01

    Fusion energy production has an inherent advantage over fission: a fuel supply with reduced long term radioactivity. One of the leading candidate materials for structural applications in a fusion reactor is a tungsten stabilized 9% chromium Martensitic steel. This alloy class is being considered because it offers the opportunity to maintain that advantage in the reactor structure as well as provide good high temperature strength and radiation induced swelling and embrittlement resistance. However, calculations indicate that to obtain acceptable radioactivity levels within 500 years after service, clean steel will be required because the niobium impurity levels must be kept below about 2 appm and nickel, molybdenum, nitrogen, copper, and aluminum must be intentionally restricted. International efforts are addressing the problems of clean steel production. Recently, a 5,000 kg heat was vacuum induction melted in Japan using high purity commercial raw materials giving niobium levels less than 0.7 appm. This paper reviews the need for reduced long term radioactivity, defines the advantageous properties of the tungsten stabilized Martensitic steel class, and describes the international efforts to produce acceptable clean steels.

  7. Scaled-up bioconversion of fish waste to liquid fertilizer using a 5 L ribbon-type reactor.

    Science.gov (United States)

    Dao, Van Thingoc; Kim, Joong Kyun

    2011-10-01

    A scaled-up conversion process of fish waste to liquid fertilizer was performed in a 5 L ribbon-type reactor. Biodegradation was performed by inoculation of autoclaved fish waste with 5.84 × 10(5) CFU mL(-1) of mixed microorganisms for 96 h. As a result, the pH changed from 6.92 to 5.72, the cell number reached 7.28 × 10(5) CFU mL(-1), and approximately 430 g (28.3%) of fish waste was degraded. Analyses indicated that the 96 h culture of inoculated fish waste possessed comparable fertilizing ability to commercial fertilizers in hydroponic culture with amino acid contents of 6.91 g 100 g(-1). Therefore, the scaled-up production achieved a more satisfactory fish waste degradation rate (3.61 g h(-1)) than the flask-scale production (0.24 g h(-1)). The biodegraded broth of fish waste at room temperature did not undergo putrefaction for 6 months due to the addition of 1% lactate.

  8. Thermochemical surface engineering of steels

    DEFF Research Database (Denmark)

    Thermochemical Surface Engineering of Steels provides a comprehensive scientific overview of the principles and different techniques involved in thermochemical surface engineering, including thermodynamics, kinetics principles, process technologies and techniques for enhanced performance of steels...

  9. Continuous steel production and apparatus

    Science.gov (United States)

    Peaslee, Kent D.; Peter, Jorg J.; Robertson, David G. C.; Thomas, Brian G.; Zhang, Lifeng

    2009-11-17

    A process for continuous refining of steel via multiple distinct reaction vessels for melting, oxidation, reduction, and refining for delivery of steel continuously to, for example, a tundish of a continuous caster system, and associated apparatus.

  10. Fatigue damage of steel components

    DEFF Research Database (Denmark)

    Fæster, Søren; Zhang, Xiaodan; Huang, Xiaoxu

    2014-01-01

    Railway rails and the inner ring in roller bearings in wind turbines are both experiencing steel-to-steel contact in small areas with huge loads resulting in extremely high stresses in the base materials......Railway rails and the inner ring in roller bearings in wind turbines are both experiencing steel-to-steel contact in small areas with huge loads resulting in extremely high stresses in the base materials...

  11. A-3 steel work completed

    Science.gov (United States)

    2009-01-01

    Stennis Space Center engineers celebrated a key milestone in construction of the A-3 Test Stand on April 9 - completion of structural steel work. Workers with Lafayette (La.) Steel Erector Inc. placed the last structural steel beam atop the stand during a noon ceremony attended by more than 100 workers and guests.

  12. Joints in steel buildings

    Directory of Open Access Journals (Sweden)

    Gabriel F. Valencia Clement

    2010-04-01

    Full Text Available Masonry and steel components used in constructing buildings are in a constant state of motion. Volumetric changes are produced by temperature variation and deformation resulting from static or dynamic loading and in some materials, such as masonry, due to moisture content. This article addresses means of determining when expansion and seismic joints are required and how to proportion and design appropriate joints, specifically in steel buildings. It does not cover the study of expansion joints in concrete structures, in masonry construction or in non-structural (architectural elements.

  13. Microbial-Influenced Corrosion of Corten Steel Compared with Carbon Steel and Stainless Steel in Oily Wastewater by Pseudomonas aeruginosa

    Science.gov (United States)

    Mansouri, Hamidreza; Alavi, Seyed Abolhasan; Fotovat, Meysam

    2015-07-01

    The microbial corrosion behavior of three important steels (carbon steel, stainless steel, and Corten steel) was investigated in semi petroleum medium. This work was done in modified nutrient broth (2 g nutrient broth in 1 L oily wastewater) in the presence of Pseudomonas aeruginosa and mixed culture (as a biotic media) and an abiotic medium for 2 weeks. The behavior of corrosion was analyzed by spectrophotometric and electrochemical methods and at the end was confirmed by scanning electron microscopy. The results show that the degree of corrosion of Corten steel in mixed culture, unlike carbon steel and stainless steel, is less than P. aeruginosa inoculated medium because some bacteria affect Corten steel less than other steels. According to the experiments, carbon steel had less resistance than Corten steel and stainless steel. Furthermore, biofilm inhibits separated particles of those steels to spread to the medium; in other words, particles get trapped between biofilm and steel.

  14. Estudo das tensões residuais de juntas soldadas de aço API 5L X80

    Directory of Open Access Journals (Sweden)

    Bruno Allison Araújo

    2013-09-01

    Full Text Available Este trabalho teve por objetivo determinar os níveis de tensões residuais decorrentes de processos de soldagem em juntas soldadas de um aço API 5L X80. Inicialmente foram executados os procedimentos de soldagem das juntas utilizando os processos de soldagem eletrodo revestido - Shielded Metal Arc Welding (SMAW e eletrodo de tungstênio com proteção gasosa - Gas Tungsten Arc Welding (GTAW, variando-se os consumíveis utilizados e empregando-se uma temperatura de interpasse de 175ºC, obtendo-se, desta maneira, três juntas soldadas. Foram avaliadas as regiões superiores e inferiores das juntas, determinando-se os níveis de tensões residuais transversais e longitudinais. As medidas de tensão residual foram realizadas por difratometria de raios-x através de um difratômetro portátil e respectivo software para análise dos resultados. Para a região superior das juntas soldadas, foi observado que quanto mais elevado for o aporte térmico mais compressivas foram os níveis de tensões residuais transversais, e mais deslocadas ficaram os picos de tensões trativas. Na região inferior das juntas soldadas, foi verificado que para maiores aportes térmicos, maiores foram os níveis de tensões residuais trativas na região do Metal de Solda (MS e menor foi o nível de tensões residuais trativas na Zona Termicamente Afetada (ZTA.

  15. Precipitates in electrical steels

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, Keith [Development and Market Research, Cogent Power Limited, Corporation Road, Newport, South Wales NP19 OXT (United Kingdom)], E-mail: keith.jenkins@cogent-power.com; Lindenmo, Magnus [Development and Market Research, Cogent Power Limited, Corporation Road, Newport, South Wales NP19 OXT (United Kingdom)

    2008-10-15

    Precipitates heavily influence the magnetic properties of electrical steels, either as a key controlled requirement as part of the manufacturing process or as an unwanted harmful residual in the final product. In this current work copper-manganese sulphides precipitates are the primary inhibitor species in the conventional grain-oriented (CGO) steels examined and grain boundary pinning is effective at a mean precipitate size of 30-70 nm. The growth of CuMnS has been studied and the results show that a precipitate size above {approx}100 nm allows the onset of secondary recrystallisation in the heating conditions applied. The effect of precipitates on the magnetic properties of both grain-oriented and non-oriented steels in their final product form is then examined. Examples of grain-oriented material still containing large numbers of precipitates clearly show the detrimental effects with increases in total power loss of 40% or more. Loss deterioration by about 20% is also seen in samples of high silicon non-oriented material in which titanium carbo-nitride precipitates have been observed. In this case the precipitates are believed to have formed during cooling after final annealing. Finally a grain-oriented steel with a large number of very small precipitates, which do not seem to have any harmful effect on the magnetic properties, is demonstrated.

  16. Japan steel mill perspective

    Energy Technology Data Exchange (ETDEWEB)

    Murase, K. [Kobe Steel Ltd., Tokyo (Japan)

    2004-07-01

    The international and Japan's steel industry, the coking coal market, and Japan's expectations from Canada's coal industry are discussed. Japan's steel mills are operating at full capacity. Crude steel production for the first half of 2004 was 55.8 million tons. The steel mills are profitable, but costs are high, and there are difficulties with procuring raw materials. Japan is trying to enhance the quality of coke, in order to achieve higher productivity in the production of pig iron. Economic growth is rising disproportionately in the BRICs (Brazil, Russia, India, and China), with a large increase in coking coal demand from China. On the supply side, there are several projects underway in Australia and Canada to increase production. These include new developments by Elk Valley Coal Corporation, Grande Cache Coal, Western Canadian Coal, and Northern Energy and Mining in Canada. The Elga Mine in the far eastern part of Russia is under development. But the market is expected to remain tight for some time. Japan envisions Canadian coal producers will provide a stable coal supply, expansion of production and infrastructure capabilities, and stabilization of price. 16 slides/overheads are included.

  17. Root causes for failures in flattening test in high frequency induction welded steel pipe mill

    Energy Technology Data Exchange (ETDEWEB)

    Babakri, Khalid Ali [Saudi Steel Pipe Company, Dammam, (Saudi Arabia)

    2010-07-01

    The flattening test is used to test weld integrity in high frequency induction welded (HFIW) steel pipe mills. The flattening test failures happen mostly with the formation of oxides in the weld area during HFIZ process. This study investigated the root causes for failure in flattening test due to improper process control in the HFIW steel pipe mill. Several flattening tests have been carried out on API 5L X60 steel pipes with various chemical compositions and various procedures (height of the ductility test). A microstructure analysis was also established (EDAX analysis). Based on the experimental data, it is found that the mills can improve flattening test performance by applying various policies. It is proposed that the acceptance criteria in the international specifications related to the test of weld ductility be modified. The reasonable height for measuring weld ductility is usually at two thirds of the specified outside diameter of the pipe.

  18. MECHANICAL PROPERTIES OF LONGITUDINAL SUBMERGED ARC WELDED STEEL PIPES USED FOR GAS PIPELINE OF OFFSHORE OIL

    Institute of Scientific and Technical Information of China (English)

    Z.Z. Yang; W. Tian; Q.R. Ma; Y.L. Li; J.K. Li; J.Z. Gao; H.B. Zhang; Y.H. Yang

    2008-01-01

    Since the development of offshore oil and gas, increased submarine oil and gas pipelines were installed. All the early steel pipes of submarine pipelines depended on importing because of the strict requirements of comprehensive properties, such as,anti-corrosion, resistance to pressure and so on. To research and develop domestic steel pipes used for the submarine pipeline, the Longitudinal-seam Submerged Arc Welded (LSAW) pipes were made of steel plates cut from leveled hot rolled coils by both the JCOE and UOE (the forming process in which the plate like the letter "J", "C", "O" or "U" shape, then expansion) forming processes. Furthermore, the mechanical properties of the pipe base metal and weld metal were tested, and the results were in accordance with the corresponding pipe specification API SPEC 5L or DNV-OS-F101, which showed that domestic LSAW pipes could be used for submarine oil and gas pipelines.

  19. Special steel production on common carbon steel production line

    Science.gov (United States)

    Pi, Huachun; Han, Jingtao; Hu, Haiping; Bian, Ruisheng; Kang, Jianjun; Xu, Manlin

    2004-06-01

    The equipment and technology of small bar tandem rolling line of Shijiazhuang Iron & Steel Co. in China has reached the 90's international advanced level in the 20th century, but products on the line are mostly of common carbon steel. Currently there are few steel plants in China to produce 45 steel bars for cold drawing, which is a kind of shortage product. Development of 45 steel for cold drawing has a wide market outlook in China. In this paper, continuous cooling transformation (CCT) curve of 45 steel for cold drawing used for rolling was set out first. According to the CCT curve, we determined some key temperature points such as Ac3 temperature and Ac1 temperature during the cooling procedure and discussed the precipitation microstructure at different cooling rate. Then by studying thermal treatment process of 45 steel bars for cold drawing, the influence of cooling time on microstructure was analyzed and the optimum cooling speed has been found. All results concluded from the above studies are the basis of regulating controlled cooling process of 45 steel bars for cold drawing. Finally, the feasible production process of 45 steel bars for cold drawing on common carbon steel production line combined with the field condition was recommended.

  20. X-ray diffraction study of microstructural changes during fatigue damage initiation in steel pipes

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, B., E-mail: bianca@lts.coppe.ufrj.br [Laboratory of Mechanics of Lille (LML), UMR CNRS 8107, University of Lille 1, Boulevard Paul Langevin, Cite Scientifique, 59655 Villeneuve d' Ascq (France); Lesage, J. [Laboratory of Mechanics of Lille (LML), UMR CNRS 8107, University of Lille 1, Boulevard Paul Langevin, Cite Scientifique, 59655 Villeneuve d' Ascq (France); Pasqualino, I. [Subsea Technology Laboratory (LTS), Ocean Engineering Department, COPPE/Federal University of Rio de Janeiro, PO Box 68508, Cidade Universitaria, CEP 21945-970, Rio de Janeiro/RJ (Brazil); Benseddiq, N. [Laboratory of Mechanics of Lille (LML), UMR CNRS 8107, University of Lille 1, Boulevard Paul Langevin, Cite Scientifique, 59655 Villeneuve d' Ascq (France); Bemporad, E. [Interdepartmental Laboratory of Electron Microscopy (LIME), University of Rome TRE, Via Della Vasca Navale 79, 00146 Rome (Italy)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer In this work we study the fatigue damage evolution in an API 5L X60 steel. Black-Right-Pointing-Pointer Microstructural changes and residual stresses are evaluated during fatigue tests. Black-Right-Pointing-Pointer Microdeformations and macro residual stresses are estimated by X-ray diffraction. Black-Right-Pointing-Pointer Results are discussed in view of an indicator of fatigue damage initiation. Black-Right-Pointing-Pointer This indicator could allow the prediction of residual life before macrocracking. - Abstract: Steel pipes used in the oil and gas industry undergo the action of cyclic loads that can cause their failure by fatigue. A consistent evaluation of the fatigue damage during the initiation phase should fundamentally be based on a nanoscale approach, i.e., at the scale of the dislocation network, in order to take into account the micromechanisms of fatigue damage that precede macrocrack initiation and propagation until the final fracture. In this work, microstructural changes related to fatigue damage initiation are investigated in the API 5L X60 grade steel, used in pipe manufacturing. Microdeformations and macro residual stress are evaluated using X-ray diffraction in real time during alternating bending fatigue tests performed on samples cut off from an X60 steel pipe. The aim of this ongoing work is to provide ground for further development of an indicator of fatigue damage initiation in X60 steel. This damage indicator could allow a good residual life prediction of steel pipes previously submitted to fatigue loading, before macroscopic cracking, and help to increase the reliability of these structures.

  1. History of ultrahigh carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    Wadsworth, J.; Sherby, O.D.

    1997-06-20

    The history and development of ultrahigh carbon steels (i.e., steels containing between 1 and 2.l percent C and now known as UHCS) are described. The early use of steel compositions containing carbon contents above the eutectoid level is found in ancient weapons from around the world. For example, both Damascus and Japanese sword steels are hypereutectoid steels. Their manufacture and processing is of interest in understanding the role of carbon content in the development of modern steels. Although sporadic examples of UHCS compositions are found in steels examined in the early part of this century, it was not until the mid-1970s that the modern study began. This study had its origin in the development of superplastic behavior in steels and the recognition that increasing the carbon content was of importance in developing that property. The compositions that were optimal for superplasticity involved the development of steels that contained higher carbon contents than conventional modern steels. It was discovered, however, that the room temperature properties of these compositions were of interest in their own right. Following this discovery, a period of intense work began on understanding their manufacture, processing, and properties for both superplastic forming and room temperature applications. The development of superplastic cast irons and iron carbides, as well as those of laminated composites containing UHCS, was an important part of this history.

  2. EVALUATION OF THE INHIBITORY EFFECTIVENESS OF THREE FERROCENE DERIVATIVES FOR CORROSION OF STEEL XC70 BY SPECTROSCOPY OF ELECTROCHEMICAL IMPEDANCE

    Directory of Open Access Journals (Sweden)

    O. Rahim

    2015-07-01

    Full Text Available In this work, we studied the efficacy of corrosion inhibition of carbon steel X70 in HCl 1M solution using ferrocenyl compounds prepared in VPRS laboratory, these compounds are: N-(férrocenyl méthyl-2-nitro aniline(Fc12, N-(férrocenyl méthyl-3-nitro aniline(Fc13 and N-(férrocenyl méthyl-4-nitro aniline(Fc14.The inhibitory potency of these compounds was determined by the electrochemical impedance spectroscopy (EIS. The overall results show that these compounds have varying percentages of inhibition. The adsorption of these compounds on the surface of the metal is a chemical adsorption.In HCl 1M, the compound Fc12 had the best ability of inhibition  at a concentration of 70ppm (R = 91.24%.

  3. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  4. Coated 4340 Steel

    Science.gov (United States)

    2013-08-26

    alternative coatings qualified to MIL-PRE-23377 Class N and an electroplated zinc - nickel alloy passivated with a trivalent chromium solution which is...effect of a non-chromate primer and zinc - nickel plating with non-chromate passivation as alternatives to the chromate primer and cadmium plating with...NAWCADPAX/TR-2013/252 COATED 4340 STEEL by E. U. Lee C. Lei M. Stanley B. Pregger C. Matzdorf 26 August 2013

  5. Ferrium M54 Steel

    Science.gov (United States)

    2015-03-18

    Examination ................................................................................................. 2 Zinc - Nickel Alloy Plating...resistance measurements using scans from 100 mV below to 100mV above at a scan rate of 0.167 mV/s. ZINC - NICKEL ALLOY PLATING The Zn-14% Ni alloy...release; distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Bare and Zn-14% Ni alloy coated Ferrium M54 steels were studied to

  6. 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.

  7. PHOSPHORUS REMOVAL USING STEEL SLAG

    Institute of Scientific and Technical Information of China (English)

    Y.Z. Lan; S. Zhang; J.K. Wang; R. W. Smith

    2006-01-01

    Steel slag is a byproduct produced in large amounts in the steel-making process. It is an important resource that can be effectively utilized. An experiment was described in which steel slag was tested as an adsorbent for the removal of phosphorus from waste water. Phosphorus removal depended on the amount of steel slag added, the pH value, the contact time, and the initial concentration. Under laboratory conditions when the added slag was 7.5g/L, the contact time 2h, and the pH value was equivalent to 6.5, over 99% of the phosphorus was removed; the experimental data on steel slag adsorption of phosphorus in the water fitted the Freundlich isotherm model. Steel slag was found to be very effective in adsorbing phosphorus.

  8. Mechanics in Steels through Microscopy

    OpenAIRE

    Tirumalasetty, G. K.

    2013-01-01

    The goal of the study consolidated in this thesis is to understand the mechanics in steels using microscopy. In particular, the mechanical response of Transformation Induced Plasticity (TRIP) steels is correlated with their microstructures. Chapter 1 introduces the current state of the art of TRIP steels, highlighting the importance of microstructure - mechanical properties - applications relationships. In Chapter 2 the material properties and material processing are described into more detai...

  9. Output Model of Steel Plant

    Institute of Scientific and Technical Information of China (English)

    ZHANG Long-qiang; TIAN Nai-yuan; ZHANG Jin; XU An-jun

    2008-01-01

    Based on the requirement of compactivity, continuity, and high efficiency, and taking full advantage of cushion capability of flexible parts such as external refining in new generation steel plant, an output model of steel plant was established in terms of matching between BOF and caster. Using this model, the BOF nominal capacity is selected, the caster output and equipment amount are computed, and then the steel plant output is computed.

  10. A pro-inflammatory role of C5L2 in C5a-primed neutrophils for ANCA-induced activation.

    Directory of Open Access Journals (Sweden)

    Jian Hao

    Full Text Available BACKGROUND: The complement system is crucial for the development of antineutrophil cytoplasmic antibody (ANCA-associated vasculitis (AAV. In particular, C5a and its receptor on neutrophils, CD88, play a central role. The functional role of the second receptor of C5a, C5L2, remains unclear. In the current study, we investigated the role of C5L2 in C5a-primed neutrophils for ANCA-induced activation. METHODS: The effect of blocking C5L2 by anti-human C5L2 blocking antibody were tested on respiratory burst and degranulation of C5a-primed neutrophils activated with ANCA, as well as on membrane-bound proteinase 3 (mPR3 and concentration of myeloperoxidase (MPO in supernatant of C5a-primed neutrophils. An antagonist for CD88 was also employed. RESULTS: Blocking C5L2 resulted in a significantly decreased MPO concentration in the supernatant of C5a-primed neutrophils. mPR3 expression increased from 209.0±43.0 in untreated cells to 444.3±60.8 after C5a treatment (P<0.001, and decreased to 375.8±65.44, 342.2±54.3 and 313.7±43.6 by pre-incubating blocking C5L2 antibody at 2.5 µg/ml, 5 µg/ml or 10 µg/ml (compared with C5a-priming group, P<0.001, P<0.001, and P<0.001, respectively. In C5a-primed neutrophils, subsequently activating with MPO-ANCA-positive IgG, the MFI value was 425.8±160.6, which decreased to 292.8±141.2, 289.7±130.0 and 280.3±136.4 upon pre-incubation with mouse anti-human C5L2 blocking antibody at 2.5 µg/ml, 5 µg/ml or 10 µg/ml (compared with C5a-primed neutrophils, for MPO-ANCA-positive IgG-induced activation, P<0.05, P<0.05, and P<0.05, respectively. Blocking C5L2 also resulted in significantly decreased C5a-primed neutrophils for PR3-ANCA-positive IgG-induced activation. Moreover, the lactoferrin concentration in the supernant significantly decreased in pre-incubation with anti-human C5L2 blocking antibody, compared with C5a-primed neutrophils induced by PR3- or MPO-ANCA-positive IgG. CONCLUSIONS: C5L2 may be implicated in

  11. Structural and electrical conductivity studies on the solid electrolyte system {sub x}Li2O-(100-x) [0.5B{sub 2}O{sub 3}-0.5 P{sub 2}O{sub 5}] where 20<x<70

    Energy Technology Data Exchange (ETDEWEB)

    Padmasree, K. P.; Diaz-Guillen, M. R.; Diaz-Guillen, J. A.; Mendoza, E. M.; Fuentes, A. F. [Cinvestav, unidad Saltillo, Ramos Arizpe, Coahuila (Mexico)]. E-mail: padma512@yahoo.com

    2009-09-15

    Lithium ion conducting glasses have been extensively investigated due to their potential application as solid state amorphous electrolytes in lithium rechargeable batteries. The use of glassy electrolytes in all solid state devices may provide numerous advantages like increased safety, facility of fabrication and miniaturization and having a higher conductivity than those of the crystalline counterparts. In this work, we prepared and studied the Lithium ion conducting glassy solid electrolytes of the composition {sub x}Li{sub 2}O-(1-x)[0.5B{sub 2}O{sub 3} -0.5P{sub 2}O{sub 5}] where 20<x<70, by melt quenching technique. The obtained solid material is characterized through X-ray diffraction (XRD), Differential thermal analysis (DTA), and Fourier transform infra-red spectrometry (FTIR) and impedance spectroscopy techniques. The conductivity obtained is of the order of 10-7S/cm at room temperature and IR spectra reveal that the glass matrix undergoes structural modification with the addition of the glass modifier Li{sub 2}O. [Spanish] Los vidrios conductores de ion litio se han investigado ampliamente por su aplicacion potencial como electrolitos amorfos de estado solido en baterias recargables de litio. El uso de electrolitos vitreos en todos los dispositivos de estado solido puede proporcionar numerosas ventajas como mayor seguridad, facilidad de fabricacion y miniaturizacion, asi como tener una conductividad mas alta que la de sus contrapartes cristalinas. En este trabajo, se prepararon y estudiaron los electrolitos solidos vitreos conductores de ion litio de la composicion {sub x}Li2O-(1-x)[0.5B{sub 2}O{sub 3} -0.5P{sub 2}O{sub 5}] donde 20<x<70, por medio de la tecnica de templado. El material solido obtenido se caracteriza mediante difraccion de rayos X (DRX), analisis termico diferencial (ATD) y espectrometria infrarroja de la transformada de Fourier (EITF) y tecnicas de espectroscopia por impedancia. La conductividad obtenida es del orden de 10-7S/cm a

  12. Evaluación de la susceptibilidad a la corrosión por picado del acero API 5L x42 expuesto a un ambiente con cloruros y CO2 mediante la técnica de ruido electroquímico

    Directory of Open Access Journals (Sweden)

    Rodríguez-Vanegas, N.

    2011-10-01

    Full Text Available The concentration of chloride ions and the partial pressure of CO2 play an important role in the degradation of low-carbon steels used for the construction of pipelines in oil and gas industry. In order to evaluate the susceptibility of carbon steel API 5L X42 to pitting corrosion electrochemical noise and linear polarization resistance measurements were carried out in aqueous solutions containing chloride ions and CO2. The concentration of chloride ions was varied between, 10000 and 18000 ppm, and the CO2 partial pressure between 10 psi and 18 psi. Experimental results pointed out that the formation of protective layer, consisting mainly of FeCO 3, depends on the partial pressure of CO2 in the system. Nevertheless, the stability of this layer was considerably affected by increasing the concentration of chloride ions causing that localized corrosion has taken place in some areas of the surface of API 5L X42, which were detected by electrochemical noise echnique.La concentración de iones cloruro y la presión parcial de CO2, tienen un papel importante en el proceso de degradación de los aceros de bajo carbono empleados en la construcción de líneas de transporte en industrias petroleras. Con el fin de evaluar la susceptibilidad del acero al carbono API 5L X42 a la corrosión por picado, se realizaron medidas de ruido electroquímico y resistencia a la polarización lineal en soluciones acuosas de iones cloruro con concentraciones entre 10.000 y 18.000 ppm, variando la presión parcial de CO2 entre 10 psi y 18 psi. Los resultados indican que la formación de una capa protectora, constituida principalmente por FeCO3, depende de la presión parcial de CO2 del sistema. No obstante, la estabilidad de dicha capa es afectada significativamente por el aumento de la concentración de iones cloruro, que producen fenómenos de corrosión localizada en algunas áreas de la superficie del acero API 5L X42, los cuales fueron detectados por la técnica de

  13. Tough Year Ahead for Steel

    Institute of Scientific and Technical Information of China (English)

    REN WEI

    2006-01-01

    @@ The steel industry, a top beneficiary of the country's sizzling economic growth, is this year likely to see only a meager profit or even report losses, according to a report by the National Development and Reform Commission. Mounting demand for steel in real estate construction and auto making during the past years resulted in an investment craze into the sector, and has caused a glut on the market. Average steel prices fell by a third last year, though domestic steel makers still managed to post a profit of 127.4 billion yuan (US$15.9 billion) on aggregate.

  14. High strength, tough alloy steel

    Science.gov (United States)

    Thomas, Gareth; Rao, Bangaru V. N.

    1979-01-01

    A high strength, tough alloy steel is formed by heating the steel to a temperature in the austenite range (1000.degree.-1100.degree. C.) to form a homogeneous austenite phase and then cooling the steel to form a microstructure of uniformly dispersed dislocated martensite separated by continuous thin boundary films of stabilized retained austenite. The steel includes 0.2-0.35 weight % carbon, at least 1% and preferably 3-4.5% chromium, and at least one other substitutional alloying element, preferably manganese or nickel. The austenite film is stable to subsequent heat treatment as by tempering (below 300.degree. C.) and reforms to a stable film after austenite grain refinement.

  15. Hydrogen Embrittlement of Gun Steel

    Science.gov (United States)

    1987-11-01

    8217s HY80 and HY130 steels were checked for the critical hydrogen concentrations which were determined to be 6 ppm for HY8O steel 8 and 3 ppm for HY130...JOTC FILE COPY AD-A188 972 AD 1 TECHNICAL REPORT ARCCB-TR-87030 HYDROGEN EMBRITTLEMENT OF GUN STEEL F’ GERALD L. SPFNCER DTIC DEC 1 5 1987 NOVEMBER...PtEtIOC COVERED HYDROGEN EMBRITTLEHENT OF GUN STEEL Final OG EOTNME 6. PERFORMINGORO EOTNME 7. A*JTNOR(s) S. CONTRACT OR GRANT NUMBER(&) Gerald L

  16. Milled Die Steel Surface Roughness Correlation with Steel Sheet Friction

    DEFF Research Database (Denmark)

    Berglund, J.; Brown, C.A.; Rosén, B.-G.

    2010-01-01

    This work investigates correlations between the surface topography ofmilled steel dies and friction with steel sheet. Several die surfaces were prepared by milling. Friction was measured in bending under tension testing. Linear regression coefficients (R2) between the friction and texture...

  17. Steel designers' handbook

    CERN Document Server

    Gorenc, Branko; Tinyou, Ron

    2012-01-01

    The Revised 7th Edition of Steel Designers' Handbook is an invaluable tool for all practising structural, civil and mechanical engineers as well as engineering students at university and TAFE in Australia and New Zealand. It has been prepared in response to changes in the design Standard AS 4100, the structural Design Actions Standards, AS /ANZ 1170, other processing Standards such as welding and coatings, updated research as well as feedback from users. This edition is based on Australian Standard (AS) 4100: 1998 and subsequent amendments. The worked numerical examples in the book have been e

  18. The industrial ecology of steel

    Energy Technology Data Exchange (ETDEWEB)

    Considine, Timothy J.; Jablonowski, Christopher; Considine, Donita M.M.; Rao, Prasad G.

    2001-03-26

    This study performs an integrated assessment of new technology adoption in the steel industry. New coke, iron, and steel production technologies are discussed, and their economic and environmental characteristics are compared. Based upon detailed plant level data on cost and physical input-output relations by process, this study develops a simple mathematical optimization model of steel process choice. This model is then expanded to a life cycle context, accounting for environmental emissions generated during the production and transportation of energy and material inputs into steelmaking. This life-cycle optimization model provides a basis for evaluating the environmental impacts of existing and new iron and steel technologies. Five different plant configurations are examined, from conventional integrated steel production to completely scrap-based operations. Two cost criteria are used to evaluate technology choice: private and social cost, with the latter including the environmental damages associated with emissions. While scrap-based technologies clearly generate lower emissions in mass terms, their emissions of sulfur dioxide and nitrogen oxides are significantly higher. Using conventional damage cost estimates reported in the literature suggests that the social costs associated with scrap-based steel production are slightly higher than with integrated steel production. This suggests that adopting a life-cycle viewpoint can substantially affect environmental assessment of new technologies. Finally, this study also examines the impacts of carbon taxes on steel production costs and technology choice.

  19. Mechanics in Steels through Microscopy

    NARCIS (Netherlands)

    Tirumalasetty, G.K.

    2013-01-01

    The goal of the study consolidated in this thesis is to understand the mechanics in steels using microscopy. In particular, the mechanical response of Transformation Induced Plasticity (TRIP) steels is correlated with their microstructures. Chapter 1 introduces the current state of the art of TRIP s

  20. Mechanics in Steels through Microscopy

    NARCIS (Netherlands)

    Tirumalasetty, G.K.

    2013-01-01

    The goal of the study consolidated in this thesis is to understand the mechanics in steels using microscopy. In particular, the mechanical response of Transformation Induced Plasticity (TRIP) steels is correlated with their microstructures. Chapter 1 introduces the current state of the art of TRIP

  1. CORROSION INHIBITOR FOR CARBON STEELS

    African Journals Online (AJOL)

    corrosion inhibitor for carbon steel in 3% ac]neon.s' NaCl solution (pH 6) ... compared to stainless steels (Buchweishaija & Hagen 1997). Organic compounds are ... resistant dust for break and clutch linings, wood binders and mould (Gedam.

  2. Hydrogen Embrittlement of Structural Steels

    Energy Technology Data Exchange (ETDEWEB)

    Somerday, Brian P.; San Marchi, Christopher W

    2014-08-01

    Carbon-manganese steels are candidates for the structural materials in hydrogen gas pipelines; however, it is well known that these steels are susceptible to hydrogen embrittlement. Decades of research and industrial experience have established that hydrogen embrittlement compromises the structural integrity of steel components. This experience has also helped identify the failure modes that can operate in hydrogen containment structures. As a result, there are tangible ideas for managing hydrogen embrittlement in steels and quantifying safety margins for steel hydrogen containment structures. For example, fatigue crack growth aided by hydrogen embrittlement is a well-established failure mode for steel hydrogen containment structures subjected to pressure cycling. This pressure cycling represents one of the key differences in operating conditions between current hydrogen pipelines and those anticipated in a hydrogen delivery infrastructure. Applying structural integrity models in design codes coupled with measurement of relevant material properties allows quantification of the reliability/integrity of steel hydrogen pipelines subjected to pressure cycling. Furthermore, application of these structural integrity models is aided by the development of physics-based predictive models, which provide important insights such as the effects of microstructure on hydrogen-assisted fatigue crack growth. Successful implementation of these structural integrity and physics-based models enhances confidence in the design codes and enables decisions about materials selection and operating conditions for reliable and efficient steel hydrogen pipelines.

  3. Great Challenge in Steel Export

    Institute of Scientific and Technical Information of China (English)

    Charlsea Liu

    2009-01-01

    @@ In 2008, the export of China steel products experienoeu, a splendid period f fast growing, and then disappointedly followed by fast depression. Until lest December, China in 2008 exported steel products of 59.21 million tons, less than the same term in 2007 by 3.48 million tons, declining about 5.6%.

  4. Corrosive Effect of Formation Water in Petroleum with High Contents of CO2 on Steel Pipelines

    Directory of Open Access Journals (Sweden)

    Alexander Cueli Corugedo

    2013-11-01

    Full Text Available The corrosion of the carbon steel pipelines of petroleum, is a serious problem, because big economic and material losses take place and in some cases damages to productive lands. The purpose of this work is to determine the aggressiveness of the formation water of the petroleum contaminated with CO2 (g, on the construction steel of the pipelines, keeping in mind the variations of temperature that happens during the course of petroleum. The Linear Polarization Resistance (LPR was used to determine the corrosion rate of the steel. It was demonstrated that the increase of the temperature and the saturation condition of CO2 in the formation water of the petroleum, increase the corrosion in the steel. The spectra of electrochemical noise results and the localization index calculated demonstrate the presence of corrosion located in the API 5L X - 52 steel surface. This result was complemented by the Optic Microscopy technique that allowed corroborating the poor adherence of the layers that were deposited on the metal and the appearance of located events increases in the environment that was investigated with the increment of the temperature and CO2 concentration.

  5. Steels from materials science to structural engineering

    CERN Document Server

    Sha, Wei

    2013-01-01

    Steels and computer-based modelling are fast growing fields in materials science as well as structural engineering, demonstrated by the large amount of recent literature. Steels: From Materials Science to Structural Engineering combines steels research and model development, including the application of modelling techniques in steels.  The latest research includes structural engineering modelling, and novel, prototype alloy steels such as heat-resistant steel, nitride-strengthened ferritic/martensitic steel and low nickel maraging steel.  Researchers studying steels will find the topics vital to their work.  Materials experts will be able to learn about steels used in structural engineering as well as modelling and apply this increasingly important technique in their steel materials research and development. 

  6. Caracterización de aceros API-5L por medio de la medición de ruido magnético Barkhausen

    OpenAIRE

    P. Martínez-Ortiz; J. H Espina-Hernández; Hallen, J. M.; R. Linares y Miranda

    2010-01-01

    En este trabajo se presenta la caracterización de aceros API- 5L (grado X52, X56, X60) a través de ruido magnético Barkhausen. Un campo magnético sinusoidal de 10 Hz de frecuencia e intensidad de 5.2 kA/m se aplicó a las muestras de acero API-5L. Se demostró que cada acero genera un señal de ruido magnético Barkhausen propia que depende de su composición química y microestructura. Se comprobó la anisotropía magnética de los aceros a través de la señal de ruido magnético Barkhausen. Se proces...

  7. Nanoprecipitation in bearing steels

    Energy Technology Data Exchange (ETDEWEB)

    Barrow, A.T.W. [SKF University Technology Centre, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 3QZ (United Kingdom); Rivera-Diaz-del-Castillo, P.E.J., E-mail: pejr2@cam.ac.uk [SKF University Technology Centre, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 3QZ (United Kingdom)

    2011-11-15

    {theta}-phase is the main hardening species in bearing steels and appears in both martensitically and bainitically hardened microstructures. This work presents a survey of the microstrucural features accompanying nanoprecipitation in bearing steels. Nanoprecipitate structures formed in 1C-1.5Cr wt.% with additions of Cr, Mn, Mo, Si and Ni are studied. The work is combined with thermodynamic calculations and neural networks to predict the expected matrix composition, and whether this will transform martensitically or bainitically. Martensite tetragonality, composition and the amount of retained austenite are related to hardness and the type of nanoprecipitate structures in martensitic grades. The {theta}-phase volume fraction, the duration of the bainite to austenite transformation and the amount of retained austenite are related to hardness and a detailed quantitative description of the precipitate nanostructures. Such description includes compositional studies using energy-dispersive spectroscopy, which shows that nanoprecipitate formation takes place under paraequilibrium. Special attention is devoted to a novel two-step bainite tempering process which shows maximum hardness; we prove that this is the most effective process for incorporating solute into the precipitates, which are finer than those resulting from one-step banitic transformation processes.

  8. Influence of the steel scrap classes on the liquid steel output molten in electric steel processes

    Directory of Open Access Journals (Sweden)

    K. Janiszewski

    2012-12-01

    Full Text Available Purpose: This is why we have analysed in the paper, using statistical analysing methods, the influence of use in the electric arc furnace charges of steel scrap of different qualities on the index of liquid steel output from a melt.Design/methodology/approach: The used research methodology consists in analytical simulation of variations in mass of liquid steel obtained from melts differing in steel scrap content in the metallic charge and statistical analyses of industrial results acquired from the corresponding process documentation (so called melt cards.Findings: Basing on the analytical and statistical analyses carried out we have determine resulting variations in the liquid steel per melt ratios depending on the content of steel scrap in the metallic charge.Research limitations/implications: The research results obtained can be utilized in each steelmaking facility, which employs the Electric Steelmaking process, in order to “design” the metallic charge compositions, having in view the quality and economic aspects.Practical implications: The research results presented in the paper can be used for steel production of high purity steels.Originality/value: The results presented in this paper are directed to the steelmakers employing the Electric Steelmaking process and constitute the authors’ original study.

  9. Improving the toughness of ultrahigh strength steel

    Energy Technology Data Exchange (ETDEWEB)

    Soto, Koji

    2002-08-15

    The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors.

  10. 49 CFR 192.55 - Steel pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for use...

  11. Stahlschüssel key to steel

    CERN Document Server

    Wegst, W S

    2016-01-01

    The Key to Steel (Stahlschlüssel/Stahlschluessel) cross reference book will help you to decode / decipher steel designations and find equivalent materials worldwide. The 2016 edition includes more than 70,000 standard designations and trade names from approximately 300 steelmakers and suppliers. Presentation is trilingual: English, French, and German. Materials covered include structural steels, tool steels, valve steels, high temperature steels and alloys, stainless and heat-resisting steels, and more. Standards and designations from 25 countries are cross-referenced.

  12. Effect of Stress on Corrosion at Crack Tip on Pipeline Steel in a Near-Neutral pH Solution

    Science.gov (United States)

    Yang, Yao; Cheng, Y. Frank

    2016-10-01

    In this work, the local corrosion at crack tip on an API 5L X46 pipeline steel specimens was investigated under various applied loads in a near-neutral pH solution. Electrochemical measurements, including potentiodynamic polarization and electrochemical impedance spectroscopy, combined with micro-electrochemical technique and surface characterization, were conducted to investigate the effect of stress on local anodic solution of the steel at the crack tip. The stress corrosion cracking of the steel was dominated by an anodic dissolution mechanism, while the effect of hydrogen was negligible. The applied load (stress) increased the corrosion rate at the crack tip, contributing to crack propagation. The deposit of corrosion products at the crack tip could protect somewhat from further corrosion. At sufficiently large applied loads such as 740 N in the work, it was possible to generate separated cathode and anode, further accelerating the crack growth.

  13. Effect of Stress on Corrosion at Crack Tip on Pipeline Steel in a Near-Neutral pH Solution

    Science.gov (United States)

    Yang, Yao; Cheng, Y. Frank

    2016-11-01

    In this work, the local corrosion at crack tip on an API 5L X46 pipeline steel specimens was investigated under various applied loads in a near-neutral pH solution. Electrochemical measurements, including potentiodynamic polarization and electrochemical impedance spectroscopy, combined with micro-electrochemical technique and surface characterization, were conducted to investigate the effect of stress on local anodic solution of the steel at the crack tip. The stress corrosion cracking of the steel was dominated by an anodic dissolution mechanism, while the effect of hydrogen was negligible. The applied load (stress) increased the corrosion rate at the crack tip, contributing to crack propagation. The deposit of corrosion products at the crack tip could protect somewhat from further corrosion. At sufficiently large applied loads such as 740 N in the work, it was possible to generate separated cathode and anode, further accelerating the crack growth.

  14. Cold-formed steel design

    CERN Document Server

    Yu, Wei-Wen

    2010-01-01

    The definitive text in the field, thoroughly updated and expanded Hailed by professionals around the world as the definitive text on the subject, Cold-Formed Steel Design is an indispensable resource for all who design for and work with cold-formed steel. No other book provides such exhaustive coverage of both the theory and practice of cold-formed steel construction. Updated and expanded to reflect all the important developments that have occurred in the field over the past decade, this Fourth Edition of the classic text provides you with more of the detailed, up-to-the-minute techni

  15. 2169 steel waveform experiments.

    Energy Technology Data Exchange (ETDEWEB)

    Furnish, Michael David; Alexander, C. Scott; Reinhart, William Dodd; Brown, Justin L.

    2012-11-01

    In support of LLNL efforts to develop multiscale models of a variety of materials, we have performed a set of eight gas gun impact experiments on 2169 steel (21% Cr, 6% Ni, 9% Mn, balance predominantly Fe). These experiments provided carefully controlled shock, reshock and release velocimetry data, with initial shock stresses ranging from 10 to 50 GPa (particle velocities from 0.25 to 1.05 km/s). Both windowed and free-surface measurements were included in this experiment set to increase the utility of the data set, as were samples ranging in thickness from 1 to 5 mm. Target physical phenomena included the elastic/plastic transition (Hugoniot elastic limit), the Hugoniot, any phase transition phenomena, and the release path (windowed and free-surface). The Hugoniot was found to be nearly linear, with no indications of the Fe phase transition. Releases were non-hysteretic, and relatively consistent between 3- and 5-mmthick samples (the 3 mm samples giving slightly lower wavespeeds on release). Reshock tests with explosively welded impactors produced clean results; those with glue bonds showed transient releases prior to the arrival of the reshock, reducing their usefulness for deriving strength information. The free-surface samples, which were steps on a single piece of steel, showed lower wavespeeds for thin (1 mm) samples than for thicker (2 or 4 mm) samples. A configuration used for the last three shots allows release information to be determined from these free surface samples. The sample strength appears to increase with stress from ~1 GPa to ~ 3 GPa over this range, consistent with other recent work but about 40% above the Steinberg model.

  16. Fabrication of stainless steel foil utilizing chromized steel strip

    Science.gov (United States)

    Loria, Edward A.

    1980-10-01

    Stainless steel foil has properties which are, in many respects, unmatched by alternative thin films. The high strength to weight ratio and resistance to corrosion and oxidation at elevated temperatures are generally advantageous. The aerospace and automotive industries have used Type 430 and 304 foil in turbine engine applications. Foil around 2 mils (5.1 × 10-3 cm) thick has been appropriate for the recuperator or heat exchanger and this product has also been used in honeycomb and truss-core structures. Further, such foil has been employed as a wrap to protect tool steel parts from contamination during heat treating. A large part of the high cost of producing stainless steel foil by rolling is due to the complicated and expensive rolling mill and annealing equipment involved. A method will be described which produces (solid) stainless steel foil from chromized (coated) steel which can be cheaper than the conventional processing stainless steel, such as Type 430, from ingot to foil. Also, the material is more ductile and less work hardenable during processing to foil and consequently intermediate annealing treatments are eliminated and scrap losses minimized.

  17. Corrosion of Steels in Steel Reinforced Concrete in Cassava Juice

    Science.gov (United States)

    Oluwadare, G. O.; Agbaje, O.

    The corrosion of two types of construction steels, ST60Mn and RST37-2♦, in a low cyanide concentration environment (cassava juice) and embedded in concrete had been studied. The ST60 Mn was found to be more corrosion resistant in both ordinary water and the cassava juice environment. The cyanide in cassava juice does not attack the steel but it provides an environment of lower pH around the steel in the concrete which leads to breakdown of the passivating film provided by hydroxyl ions from cement. Other factors such as the curing time of the concrete also affect the corrosion rates of the steel in the concrete. The corrosion rate of the steel directly exposed to cassava juice i.e., steel not embedded in concrete is about twice that in concrete. Long exposure of concrete structure to cassava processing effluent might result in deterioration of such structures. Careful attention should therefore be paid to disposal of cassava processing effluents, especially in a country like Nigeria where such processing is now on the increase.

  18. Steels for cryogenic power engineering

    Energy Technology Data Exchange (ETDEWEB)

    Ermakov, B.S.; Nikolaich A.Y.; Oparin, V.A.

    1986-09-01

    The authors investigated steels containing 0.9% C and 30% Mnwhich were additionally alloyed with 2, 4, 6, 8, 10, and 11% Al. Phase analysis on a diffractometer established that steels containing up to 10% Al have a single-phase austenitic structure and do not undergo any transformations whatsoever in plastic deformation and when cooled to 4 K. The magnetic permeability in an external magnetic field with intensity 620 kA/m and the mechanical properties of the investigated steels are presented in a table. These properties improve when their aluminum content increases to 10%; further alloying with aluminum causes some impairment of the plastic and ductile properties which is connected with the formation of alpha-phase in the structure of the steels.

  19. Weld bonding of stainless steel

    DEFF Research Database (Denmark)

    Santos, I. O.; Zhang, Wenqi; Goncalves, V.M.

    2004-01-01

    This paper presents a comprehensive theoretical and experimental investigation of the weld bonding process with the purpose of evaluating its relative performance in case of joining stainless steel parts, against alternative solutions based on structural adhesives or conventional spot...

  20. MICROALLOYED STEELS FOR THE AUTOMOTIVE INDUSTRY

    Directory of Open Access Journals (Sweden)

    Debanshu Bhattacharya

    2014-12-01

    Full Text Available Two major drivers for the use of newer steels in the automotive industry are fuel efficiency and increased safety performance. Fuel efficiency is mainly a function of weight of steel parts, which in turn, is controlled by gauge and design. Safety is determined by the energy absorbing capacity of the steel used to make the part. All of these factors are incentives for the U.S. automakers to use both Highly Formable and Advanced High Strength Steels (AHSS to replace the conventional steels used to manufacture automotive parts in the past. AHSS is a general term used to describe various families of steels. The most common AHSS is the dual-phase steel that consists of a ferrite-martensite microstructure. These steels are characterized by high strength, good ductility, low tensile to yield strength ratio and high bake hardenability. Another class of AHSS is the complex-phase or multi-phase steel which has a complex microstructure consisting of various phase constituents and a high yield to tensile strength ratio. Transformation Induced Plasticity (TRIP steels is another class of AHSS steels finding interest among the U.S. automakers. These steels consist of a ferrite-bainite microstructure with significant amount of retained austenite phase and show the highest combination of strength and elongation, so far, among the AHSS in use. High level of energy absorbing capacity combined with a sustained level of high n value up to the limit of uniform elongation as well as high bake hardenability make these steels particularly attractive for safety critical parts and parts needing complex forming. A relatively new class of AHSS is the Quenching and Partitioning (Q&P steels. These steels seem to offer higher ductility than the dual-phase steels of similar strengths or similar ductility as the TRIP steels at higher strengths. Finally, martensitic steels with very high strengths are also in use for certain parts. The most recent initiative in the area of AHSS

  1. Hydrogen embrittlement of structural steels.

    Energy Technology Data Exchange (ETDEWEB)

    Somerday, Brian P.

    2010-06-01

    Carbon-manganese steels are candidates for the structural materials in hydrogen gas pipelines, however it is well known that these steels are susceptible to hydrogen embrittlement. Decades of research and industrial experience have established that hydrogen embrittlement compromises the structural integrity of steel components. This experience has also helped identify the failure modes that can operate in hydrogen containment structures. As a result, there are tangible ideas for managing hydrogen embrittement in steels and quantifying safety margins for steel hydrogen containment structures. For example, fatigue crack growth aided by hydrogen embrittlement is a key failure mode for steel hydrogen containment structures subjected to pressure cycling. Applying appropriate structural integrity models coupled with measurement of relevant material properties allows quantification of safety margins against fatigue crack growth in hydrogen containment structures. Furthermore, application of these structural integrity models is aided by the development of micromechanics models, which provide important insights such as the hydrogen distribution near defects in steel structures. The principal objective of this project is to enable application of structural integrity models to steel hydrogen pipelines. The new American Society of Mechanical Engineers (ASME) B31.12 design code for hydrogen pipelines includes a fracture mechanics-based design option, which requires material property inputs such as the threshold for rapid cracking and fatigue crack growth rate under cyclic loading. Thus, one focus of this project is to measure the rapid-cracking thresholds and fatigue crack growth rates of line pipe steels in high-pressure hydrogen gas. These properties must be measured for the base materials but more importantly for the welds, which are likely to be most vulnerable to hydrogen embrittlement. The measured properties can be evaluated by predicting the performance of the pipeline

  2. The candidate genes TAF5L, TCF7, PDCD1, IL6 and ICAM1 cannot be excluded from having effects in type 1 diabetes

    Directory of Open Access Journals (Sweden)

    Vella Adrian

    2007-11-01

    Full Text Available Abstract Background As genes associated with immune-mediated diseases have an increased prior probability of being associated with other immune-mediated diseases, we tested three such genes, IL23R, IRF5 and CD40, for an association with type 1 diabetes. In addition, we tested seven genes, TAF5L, PDCD1, TCF7, IL12B, IL6, ICAM1 and TBX21, with published marginal or inconsistent evidence of an association with type 1 diabetes. Methods We genotyped reported polymorphisms of the ten genes, nonsynonymous SNPs (nsSNPs and, for the IL12B and IL6 regions, tag SNPs in up to 7,888 case, 8,858 control and 3,142 parent-child trio samples. In addition, we analysed data from the Wellcome Trust Case Control Consortium genome-wide association study to determine whether there was any further evidence of an association in each gene region. Results We found some evidence of associations between type 1 diabetes and TAF5L, PDCD1, TCF7 and IL6 (ORs = 1.05 – 1.13; P = 0.0291 – 4.16 × 10-4. No evidence of an association was obtained for IL12B, IRF5, IL23R, ICAM1, TBX21 and CD40, although there was some evidence of an association (OR = 1.10; P = 0.0257 from the genome-wide association study for the ICAM1 region. Conclusion We failed to exclude the possibility of some effect in type 1 diabetes for TAF5L, PDCD1, TCF7, IL6 and ICAM1. Additional studies, of these and other candidate genes, employing much larger sample sizes and analysis of additional polymorphisms in each gene and its flanking region will be required to ascertain their contributions to type 1 diabetes susceptibility.

  3. Streamlining Iron and Steel Production

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Eliminating unproductive iron and steel facilities is vital to environmental protection and sustainable development of this industry The Chinese Government is once again shutting down unproductive plants in tune with its green policy and the march toward sustainable development.This time it’s the iron and steel industry to feel the brunt of the Chinese Government’s stringent measures. The deafening buzz of factory floors have

  4. Rapid Cycle Casting of Steel

    Science.gov (United States)

    1981-07-01

    such as macrosegregation, hot tears, and blowholes are also difficult to control. Rheocasting l on the other hand, is a recent development which...viscosity. Advantages of the rheocasting process are: * Reduced attack of die or mold because of the reduced tempera- ture (by 1000 C for steel) and...4W W ’ V6W 4 1.2 THE SD PROCESS Many metals, including steel, can be cast at still lower tempera- soliifiction(2) tures than rheocasting by

  5. Analysis of plasma nitrided steels

    Science.gov (United States)

    Salik, J.; Ferrante, J.; Honecy, F.; Hoffman, R., Jr.

    1987-01-01

    The analysis of plasma nitrided steels can be divided to two main categories - structural and chemical. Structural analysis can provide information not only on the hardening mechanisms but also on the fundamental processes involved. Chemical analysis can be used to study the kinetics for the nitriding process and its mechanisms. In this paper preliminary results obtained by several techniques of both categories are presented and the applicability of those techniques to the analysis of plasma-nitrided steels is discussed.

  6. 高钢级管线钢变形抗力模型%Research on mathematical model for the deformation resistance of high strength pipeline steel

    Institute of Scientific and Technical Information of China (English)

    林鹏飞; 胡水平; 余伟; 宋晓波

    2011-01-01

    The test study for plastic deformation resistance of two kinds of high strength pipeline steels with different components was engaged in single pass compression test by Gleeble-3500. The influence of deforming temperature, deforming velocity and deforming degree on deformation resistance were analyzed and a new model of deformation resistance suitable for X70 and X80 steels was established. Through multiple linear regression analysis, this model proved to have good curve fitting characteristics and relatively high precision. The model has been successfully used in rolling production with relative error of rolling force less than eleven percent%利用Gleeble-3500热模拟试验机,对两种不同成分的高钢级管线钢进行单道次压缩实验的塑性变形抗力进行研究.分析了变形温度、变形速率、变形程度对变形抗力的影响,建立一种适合X70、X80高钢级管线钢的变形抗力模型.通过多元非线性进行回归分析,证明模型具有良好的曲线拟合特性.模型成功的应用于轧制生产的现场,计算出的轧制力值误差控制在11%以内.

  7. THE STRUCTURAL ANALYSIS OF STEEL SILOS WITH CYLINDRICAL-WALL BEARING AND PROFILE-STEEL BEARING

    Directory of Open Access Journals (Sweden)

    Zhengjun Tang

    2015-04-01

    Full Text Available The silos are widely used in bulk material in many fields such as agriculture, mining, chemical, electric power storage, etc. Thin metal cylindrical silo shells are vulnerable to buckling failure caused by the compressive wall friction force. In this paper, the structural analysis of two types of steel silo with cylindrical-wall bearing and profile-steel bearing is implemented by Abaqus finite element analysis. The results indicate that under the same loading conditions, steel silos with profile-steel bearing and cylindrical-Wall bearing have similar values in Mises stress, but the steel silo with profile-steel bearing has a smaller radial displacement and a better capability of buckling resistance. Meanwhile, the total steel volumes reduced 8.0% comparing to the steel silo with cylindrical-wall bearing. Therefore, steel soil with profile-steel bearing not only has a less steel volumes but also a good stability.

  8. Review on Cold-Formed Steel Connections

    Science.gov (United States)

    Tan, Cher Siang; Mohammad, Shahrin; Md Tahir, Mahmood; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  9. Some peculiarities of corrosion of wheel steel

    Directory of Open Access Journals (Sweden)

    Alexander SHRAMKO

    2009-01-01

    Full Text Available Corrosion mechanism and rate of different chemical composition and structural condition of wheel steel were investigated. It was shown that “white layers”, variation in grain size and banding of wheel steel structure results in corrosion rate. Microstructure of steel from different elements of railway wheels after operation with corrosion was investigated. Wheel steel with addition of vanadium corroded more quickly than steel without vanadium. Non-metallic inclusions are the centre of corrosion nucleation and their influence on corrosion depends on type of inclusion. Mechanism of corrosion of wheel steel corrosion was discussed.

  10. Kinetics of borided gear steels

    Indian Academy of Sciences (India)

    Ibrahim Gunes

    2013-06-01

    In this study, the case properties and diffusion kinetics of GS18NiMoCr36 (GS18), GS22NiMoCr56 (GS22) and GS32NiCrMo6.4 (GS32) gear steels borided in Ekabor-II powder were investigated by conducting a series of experiments at temperatures of 1123, 1173 and 1223 K for 2, 4 and 6 h. The boride layer was characterized by optical microscopy, X-ray diffraction technique and microVickers hardness tester. X-ray diffraction analysis of boride layers on the surface of the steels revealed the existence of FeB, Fe2B, CrB and Cr2B compounds. The thickness of the boride layer increases by increasing boriding time and temperature for all steels. The hardness of the boride compounds formed on the surface of the steels GS18, GS22 and GS32 ranged from 1624 to 1905 HV0,05, 1702 to 1948 HV0,05, and 1745 to 2034 HV0,05 respectively, whereas Vickers hardness values of the untreated steels GS18, GS22 and GS32 were 335 HV0,05, 358 HV0,05 and 411 HV0,05, respectively. The activation energies (Q) of borided steels were 228.644 kJ/mol for GS18, 280.609 kJ/mol for GS22 and 294.359 kJ/mol for GS32. The growth kinetics of the boride layers forming on the GS18, GS22 and GS32 steels and the thickness of boride layers were also investigated.

  11. The microstructure of chromium-tungsten steels

    Science.gov (United States)

    Klueh, R. L.; Maziasz, P. J.

    1989-03-01

    Chromium-tungsten steels are being developed to replace the Cr-Mo steels for fusion-reactor applications. Eight experimental steels were produced and examined by optical and electron microscopy. Chromium concentrations of 2.25, 5, 9 and 12 pct were used. Steels with these chromium compositions and with 2 pct W and 0.25 pct V were produced. To determine the effect of tungsten and vanadium, three other 2.25Cr steels were produced as follows: an alloy with 2 pct W and 0 pct V and alloys with 0 and 1 pct W and 0.25 pct V. A 9Cr steel containing 2 pct W, 0.25 pct V, and 0.07 pct Ta also was studied. For all alloys, carbon was maintained at 0.1 pct. Two pct tungsten was required in the 2.25Cr steels to produce 100 pct bainite (no polygonal ferrite). The 5Cr and 9Cr steels were 100 pct martensite, but the 12Cr steel contained about 25 pct delta-ferrite. Precipitate morphology and precipitate types varied, depending on the chromium content. For the 2.25Cr steels, M3C and M7C3 were the primary precipitates; for the 9Cr and 12Cr steels, M23C6 was the primary precipitate. The 5Cr steel contained M7C3 and M23C6. All of the steels with vanadium also contained MC.

  12. Towards Responsible Steel: Preliminary Insights

    Directory of Open Access Journals (Sweden)

    Suzanne Benn

    2014-03-01

    Full Text Available This paper examines the structures and processes underpinning the attempt of the Australian steel industry to establish a certification scheme for Responsible Steel. We take it as a case example of how collective action and collaboration along a supply chain has the potential to be a win-win situation for the environment and for the competitiveness of an industry sector. The paper identifies the drivers that have prompted key stakeholders from all major sectors of the Australian steel product life cycle from mining through steel manufacturing, processing, product fabrication, use and re-use, and recycling to collaborate in the establishment of the Steel Stewardship Forum (SSF, the structure established to lead the development of the certification scheme. The development of this initiative is indicative of the wider shift to sustainability-related certification schemes as a means of garnering legitimacy and market advantage and provides detailed insights into both the drivers for and the challenges associated with such initiatives. Findings from the paper contribute to our understanding of the shift to sustainable supply chains as it is interpreted through institutional and institutional entrepreneurship theory.

  13. Key to steel. 16. rev. and enlarged ed. Stahlschluessel

    Energy Technology Data Exchange (ETDEWEB)

    Wegst, C.W.

    1992-01-01

    The DIN substance reference numbers and abbreviations have been related to the trademarks of the steelworks and steel supplies. DIN specifications are compared with foreign specifications for different types of steel (e.g. structural steel, tool steel, noble steel, high-temperature steel). (MM).

  14. Steel erected at A-3 Test Stand

    Science.gov (United States)

    2008-01-01

    Workers erect the first fabricated steel girders to arrive at the A-3 Test Stand at Stennis Space Center. Steel work began at the construction site Oct. 29 and is scheduled to continue into next spring.

  15. Determination of the non-recrystallization temperature (TNR) in multiple microalloyed steels

    Science.gov (United States)

    Homsher, Caryn Nicole

    Rolling mill metallurgists must be able to easily and accurately determine critical temperatures such as the non-recrystallization temperature (T NR) to properly plan rolling schedules for desired properties. Microalloyed steels have small additions of alloying elements such as V, Ti, and Nb, to improve mechanical properties through grain size control and precipitation strengthening. The value of TNR is based on both alloying elements and deformation parameters. To easily predict TNR, equations have been developed and utilized in the literature and industry. However, each equation has certain limitations which constrain its applicability. This study was completed using ten laboratory grade low-carbon microalloyed steels designed to meet the API X-70 specification with varying amounts of V, Nb, and Ti. Double-hit deformation tests were conducted on a Gleeble® 3500 system in the standard pocket-jaw configuration at the Colorado School of Mines to determine experimental values of TNR. Double-hit deformation tests involve cylindrical specimens in an axisymmetric compression test. The test method requires six steps: 1) reheat to ensure most precipitates dissolve back into solution, 2) cool to deformation temperature, 3) compress with given strain and strain rate, 4) hold for interpass time, 5) deform specimen again holding everything else constant, and 6) measure the percent recrystallized or percent fractional softening. The TNR is the temperature where fractional softening is equal to 20 %. Niobium plays the largest role in influencing TNR. Complex niobium-vanadium-carbonitride precipitates are believed to play a significant role increasing TNR in the Hi-V alloy The experimental values of TNR were compared with predicted values of TNR from four equations in the literature. The Bai 2011 equation was the most reliable of the existing empirical formulas considered, while the commonly used Boratto equation was not accurate in predicting the TNR for the alloys in this

  16. An investigation into the preservation of microbial cell banks for α-amylase production during 5 l fed-batch Bacillus licheniformis fermentations.

    Science.gov (United States)

    Hancocks, Nichola H; Thomas, Colin R; Stocks, Stuart M; Hewitt, Christopher J

    2010-10-01

    Fluorescent staining techniques were used for a systematic examination of methods used to cryopreserve microbial cell banks. The aim of cryopreservation here is to ensure subsequent reproducible fermentation performance rather than just post thaw viability. Bacillus licheniformis cell physiology post-thaw is dependent on the cryopreservant (either Tween 80, glycerol or dimethyl sulphoxide) and whilst this had a profound effect on the length of the lag phase, during subsequent 5 l fed-batch fermentations, it had little effect on maximum specific growth rate, final biomass concentration or α-amylase activity. Tween 80 not only protected the cells during freezing but also helped them recover post-thaw resulting in shorter process times.

  17. Optimum design of steel structures

    CERN Document Server

    Farkas, József

    2013-01-01

    This book helps designers and manufacturers to select and develop the most suitable and competitive steel structures, which are safe, fit for production and economic. An optimum design system is used to find the best characteristics of structural models, which guarantee the fulfilment of design and fabrication requirements and minimize the cost function. Realistic numerical models are used as main components of industrial steel structures. Chapter 1 containts some experiences with the optimum design of steel structures Chapter 2 treats some newer mathematical optimization methods. Chapter 3 gives formulae for fabrication times and costs. Chapters 4 deals with beams and columns. Summarizes the Eurocode rules for design. Chapter 5 deals with the design of tubular trusses. Chapter 6 gives the design of frame structures and fire-resistant design rules for a frame. In Chapters 7 some minimum cost design problems of stiffened and cellular plates and shells are worked out for cases of different stiffenings and loads...

  18. Functionally Graded Mo sintered steels

    Directory of Open Access Journals (Sweden)

    Manuel Cisneros-Belmonte

    2016-12-01

    Full Text Available Functionally graded materials (FGM, the multi-materials, strive to satisfy the numerous requirements demanded of parts in a given combination of compositions and microstructures. The required material compatibility lead the manufacturing process and the achieving of an interface, not always diffuse. Powder metallurgy is one of the techniques used in manufacturing functionally graded materials, in particular the compaction matrix of the possible techniques for forming these materials. In this paper, a process of forming a functionally graded steel based on the use of a high molybdenum steel with cooper and other steel with copper, without molybdenum, is proposed with the aim of concentrating this element to the surface of the workpiece, increasing the mechanical strength. The study is completed with the evaluation of physical properties (density and porosity distribution, mechanical properties (hardness, tensile strength and elongation and microstructural analysis by optical and scanning electron microscopy.

  19. China Steel Pipes Demand Rising Steadily

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Steel pipes industry is an industry to play a decisive role in the national economic development. During the Tenth Five-Year Plan period, the steel pipes output has been increased distinctly. Based on experts forecast,the steel pipes demand in China will still be in tendency of increase during the Eleventh FiveYear Plan period, which will doubtlessly bring new opportunity and challenge to the steel pipes enterprises in China.

  20. Microstructural Development during Welding of TRIP steels

    OpenAIRE

    Amirthalingam, M.

    2010-01-01

    The Advanced High Strength Steels (AHSS) are promising solutions for the production of lighter automobiles which reduce fuel consumption and increase passenger safety by improving crash-worthiness. Transformation Induced Plasticity Steel (TRIP) are part of the advanced high strength steels which offers a high strength and toughness combination with excellent uniform elongation. However, the higher alloying content of these steel limits their weldability and the thermal cycle of a welding proc...

  1. MICROALLOYED STEELS FOR THE AUTOMOTIVE INDUSTRY

    OpenAIRE

    Debanshu Bhattacharya

    2014-01-01

    Two major drivers for the use of newer steels in the automotive industry are fuel efficiency and increased safety performance. Fuel efficiency is mainly a function of weight of steel parts, which in turn, is controlled by gauge and design. Safety is determined by the energy absorbing capacity of the steel used to make the part. All of these factors are incentives for the U.S. automakers to use both Highly Formable and Advanced High Strength Steels (AHSS) to replace the conventional ...

  2. Speeding up the solar water disinfection process (SODIS) against Cryptosporidium parvum by using 2.5l static solar reactors fitted with compound parabolic concentrators (CPCs).

    Science.gov (United States)

    Gómez-Couso, H; Fontán-Sainz, M; Fernández-Ibáñez, P; Ares-Mazás, E

    2012-12-01

    Water samples of 0, 5, and 100 nephelometric turbidity units (NTU) spiked with Cryptosporidium parvum oocysts were exposed to natural sunlight in 2.5l static borosilicate solar reactors fitted with two different compound parabolic concentrators (CPCs), CPC1 and CPC1.89, with concentration factors of the solar radiation of 1 and 1.89, respectively. The global oocyst viability was calculated by the evaluation of the inclusion/exclusion of the fluorogenic vital dye propidium iodide and the spontaneous excystation. Thus, the initial global oocyst viability of the C. parvum isolate used was 95.3 ± 1.6%. Using the solar reactors fitted with CPC1, the global viability of oocysts after 12h of exposure was zero in the most turbid water samples (100 NTU) and almost zero in the other water samples (0.3 ± 0.0% for 0 NTU and 0.5 ± 0.2% for 5 NTU). Employing the solar reactors fitted with CPC1.89, after 10h exposure, the global oocyst viability was zero in the non-turbid water samples (0 NTU), and it was almost zero in the 5 NTU water samples after 8h of exposure (0.5 ± 0.5%). In the most turbid water samples (100 NTU), the global viability was 1.9 ± 0.6% after 10 and 12h of exposure. In conclusion, the use of these 2.5l static solar reactors fitted with CPCs significantly improved the efficacy of the SODIS technique as these systems shorten the exposure times to solar radiation, and also minimize the negative effects of turbidity. This technology therefore represents a good alternative method for improving the microbiological quality of household drinking water in developing countries. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Prevention of corrosion in prestressing steels

    NARCIS (Netherlands)

    Polder, R.B.

    1996-01-01

    Corrosion of prestressing steel may lead to sudden, so called brittle failure, due to the special microstructure of the steel and the high tensile forces. Such brittle failure may seriously reduce the load capacity of a prestressed concrete structure. In principle all stressed high strength steel is

  4. INCREASE STRUCTURAL STRENGTH OF MARGANESE STEEL

    Directory of Open Access Journals (Sweden)

    L. N. Bunina

    2011-04-01

    Full Text Available The manganese steels are widely used in machinery construction. The influence of chemical composition and form of non-metallic inclusions on constructive strength of manganese steels is studied. The dependences between the nature of non-metallic inclusions and properties of steels are given.

  5. Microstructural Development during Welding of TRIP steels

    NARCIS (Netherlands)

    Amirthalingam, M.

    2010-01-01

    The Advanced High Strength Steels (AHSS) are promising solutions for the production of lighter automobiles which reduce fuel consumption and increase passenger safety by improving crash-worthiness. Transformation Induced Plasticity Steel (TRIP) are part of the advanced high strength steels which

  6. Microstructural Development during Welding of TRIP steels

    NARCIS (Netherlands)

    Amirthalingam, M.

    2010-01-01

    The Advanced High Strength Steels (AHSS) are promising solutions for the production of lighter automobiles which reduce fuel consumption and increase passenger safety by improving crash-worthiness. Transformation Induced Plasticity Steel (TRIP) are part of the advanced high strength steels which off

  7. A model for TRIP steel constitutive behaviour

    NARCIS (Netherlands)

    Perdahcioglu, Emin Semih; Geijselaers, Hubertus J.M.; Menari, G

    2011-01-01

    A constitutive model is developed for TRIP steel. This is a steel which contains three or four different phases in its microstructure. One of the phases in TRIP steels is metastable austenite (Retained Austenite) which transforms to martensite upon deformation. The accompanying transformation strain

  8. Teaching Steel Connections Using an Interactive Virtual Steel Sculpture

    Science.gov (United States)

    Moaveni, Saeed; Chou, Karen C.

    2015-01-01

    Steel connections play important roles in the integrity of a structure, and many structural failures are attributed to connection failures. Connections are the glue that holds a structure together. The failures of the Hartford Coliseum in 1977, the Hyatt Regency Hotel in Kansas City in 1980, and the I-35W Bridge in Minneapolis in 2007 are all…

  9. Teaching Steel Connections Using an Interactive Virtual Steel Sculpture

    Science.gov (United States)

    Moaveni, Saeed; Chou, Karen C.

    2015-01-01

    Steel connections play important roles in the integrity of a structure, and many structural failures are attributed to connection failures. Connections are the glue that holds a structure together. The failures of the Hartford Coliseum in 1977, the Hyatt Regency Hotel in Kansas City in 1980, and the I-35W Bridge in Minneapolis in 2007 are all…

  10. performance of steel slag performance of steel slag as fine ...

    African Journals Online (AJOL)

    eobe

    reduced from 0.62 to 0.50 as slag proportion increased from 0% to 100% at slump. 0.62 to 0.50 as slag ... Nigerian Journal of Technology (NIJOTECH). Vol. 34 No. 3, July ... scrap metals and hundreds of tonnes of steel slag are produced every ...

  11. Effect of steel composition and slag properties on NMI in clean steel production

    Directory of Open Access Journals (Sweden)

    Elfawakhry Mohamed K

    2016-01-01

    Full Text Available The modern steel plants for clean steel production depend to large extent on the efficiency of the refining processes that applied for the production. Refining processes that applied for low alloy and alloyed steel production include degassing via vacuum or ladle and ladle furnace units. This technique could help in producing homogeneous steel with low gas content and minimum internal defects. In certain grades of steel for tools and penetration and impact resistance uses, non-metallic inclusions (NMI and sulphur content are the key factors for the steel performance and applications. ESR, Electro-salg refining (or remelting, is the technique that can efficiently produce clean steel with minimum content of NMI and sulphur due to the special nature and mechanism of this technique. In this study, the effect of initial chemical composition of steel and slag properties on the efficiency of ESR process in removal of NMI and sulphur from steel are evaluated. Different grades of steels were refined using ESR process. The efficiency of ESR in modifying and enhancing NMI shape, size and counts as well as removal of sulphur in different steel grades was evaluated at different slag composition and physical properties. The effect of chemical composition of steel on the efficiency of ESR process was studied. It was found that ESR process has a great effect in producing clean steel where both viscosity and initial composition of steel have influence on the final NMI status and sulphur content in the produced steel.

  12. Superhard Nanocrystalline Homometallic Stainless Steel on Steel for Seamless Coatings

    Science.gov (United States)

    Tobin, Eric J.; Hafley, R. (Technical Monitor)

    2002-01-01

    The objective of this work is to deposit nanocrystalline stainless steel onto steel substrates (homometallic) for enhanced wear and corrosion resistance. Homometallic coatings provide superior adhesion, and it has been shown that ultrafine-grained materials exhibit the increased hardness and decreased permeability desired for protective coatings. Nanocrystals will be produced by controlling nucleation and growth and use of an ion beam during deposition by e-beam evaporation or sputtering. Phase I is depositing 31 6L nanocrystalline stainless steel onto 31 6L stainless steel substrates. These coatings exhibit hardnesses comparable to those normally obtained for ceramic coatings such ZrO2, and possess the superior adhesion of seamless, homometallic coatings. Hardening the surface with a similar material also enhances adhesion, by avoiding problems associated with thermal and lattice mismatch. So far we have deposited nanocrystalline homometallic 316L stainless steel coatings by varying the ions and the current density of the ion beams. For all deposition conditions we have produced smooth, uniform, superhard coatings. All coatings exhibit hardness of at least 200% harder than that of bulk materials. Our measurements indicate that there is a direct relationship between nanohardness and the current density of the ion beam. Stress measurements indicate that stress in the films is increasingly proportional to current density of the ion beam. TEM, XPS, and XRD results indicate that the coated layers consist of FCC structure nanocrystallites with a dimension of about 10 to 20 nm. The Ni and Mo concentration of these coating are lower than those of bulk 316L but the concentration of Cr is higher.

  13. Preformed posterior stainless steel crowns: an update.

    Science.gov (United States)

    Croll, T P

    1999-02-01

    For almost 50 years, dentists have used stainless steel crowns for primary and permanent posterior teeth. No other type of restoration offers the convenience, low cost, durability, and reliability of such crowns when interim full-coronal coverage is required. Preformed stainless steel crowns have improved over the years. Better luting cements have been developed and different methods of crown manipulation have evolved. This article reviews stainless steel crown procedures for primary and permanent posterior teeth. Step-by-step placement of a primary molar stainless steel crown is documented and permanent molar stainless steel crown restoration is described. A method for repairing a worn-through crown also is reviewed.

  14. Advanced sheet steels for automotive applications

    Science.gov (United States)

    Fekete, James R.; Strugala, Donald C.; Yao, Zhicong

    1992-01-01

    Vacuum degassing has recently been used by sheet steel producers to improve their products' ductility and strength. Carbon contents can be reduced by an order of magnitude to less than 0.0030 wt.%. Through careful alloying and processing, a range of new steel products has been developed for the automotive industry. These products include interstitial-free, deep-drawing-quality steels; formable, high-strength, interstitial-free steels; and bake-hardenable steels. This article summarizes the chemistry and processing needed to produce these products.

  15. Reduced-activation steels: Future development for improved creep strength

    Science.gov (United States)

    Klueh, R. L.

    2008-08-01

    Reduced-activation steels for fusion applications were developed in the 1980s to replace the elevated-temperature commercial steels first considered. The new steels were patterned after the commercial steels, with the objective that the new steels have yield stress and ultimate tensile strength and impact toughness in a Charpy test comparable to or better than the steels they replaced. That objective was achieved in reduced-activation steels developed in Japan, Europe, and the United States. Although tensile and impact toughness of the reduced-activation steels exceed those of the commercial steels they were patterned after, their creep-rupture properties are inferior to some commercial steels they replaced. They are even more inferior to commercial steels developed since the 1980s. In this paper, compositional differences between reduced-activation steels and new commercial steels are examined, and compositions are proposed for development of new-and-improved reduced-activation steels.

  16. Steel-board composite floors

    NARCIS (Netherlands)

    Couchman, G.H.; Tomà, A.W.; Brekelmans, J.W.P.M.; Brande, E.L.M.G. van den

    1999-01-01

    Work currently underway in Holland aDd the UK aims to increase the already considerable potential for light steel framing in buildings by developing rules for so-called "dry composites". This paper discusses both theoretical and experimental work to develop validated design mies for floor systems co

  17. Steel-board composite floors

    NARCIS (Netherlands)

    Couchman, G.H.; Tomà, A.W.; Brekelmans, J.W.P.M.; Brande, E.L.M.G. van den

    1999-01-01

    Work currently underway in Holland aDd the UK aims to increase the already considerable potential for light steel framing in buildings by developing rules for so-called "dry composites". This paper discusses both theoretical and experimental work to develop validated design mies for floor systems

  18. Study on cementitious properties of steel slag

    Directory of Open Access Journals (Sweden)

    Zhu G.

    2013-01-01

    Full Text Available The converter steel slag chemical and mineral components in China’s main steel plants have been analysed in the present paper. The electronic microscope, energy spectrum analysis, X-ray diffraction analysis confirmed the main mineral compositions in the converter slag. Converter slag of different components were grounded to obtain a powder with specific surface area over 400m2/kg, making them to take place some part of the cement in the concrete as the admixture and carry out the standard tests. The results indicate that the converter slag can be used as cementitious materials for construction. Furthermore, physical mechanic and durability tests on the concrete that certain amount of cement be substituted by converter steel slag powder from different steel plants are carried out, the results show that the concrete with partial substitution of steel slag powder has the advantages of higher later period strength, better frost resistance, good wear resistance and lower hydration heat, etc. This study can be used as the technical basis for “Steel Slag Powder Used For Cement And Concrete”, “Steel Slag Portland Cement”, “Low Heat Portland Steel Slag Cement”, “Steel Slag Road Cement” in China, as well as a driving force to the works of steel slag utilization with high-value addition, circular economy, energy conservation and discharge reduction in the iron and steel industry.

  19. Erosion behaviour of hydro turbine steels

    Indian Academy of Sciences (India)

    Akhilesh K Chauhan; D B Goel; Satya Prakash

    2008-04-01

    The martensitic stainless steel (termed as 13/4) is currently being used for fabrication of underwater parts in hydroelectric projects. There are, however, several maintenance problems associated with the use of this steel. A nitronic steel (termed as 21–4–N) has been developed as an alternative with the specific aim of overcoming these problems. A comparative study has been made on the erosion behaviour of 13/4 and 21–4–N steels by means of solid particle impingement using gas jet. The eroded surfaces after erosion tests were analysed by scanning electron microscopy. It is observed that the 21–4–N nitronic steel possesses better resistance to erosion in comparison to 13/4 martensitic stainless steel. The austenitic matrix of the nitronic steel possesses high hardness, high tensile toughness and work hardening ability, which results in higher erosion resistance.

  20. STEFINS: a steel freezing integral simulation program

    Energy Technology Data Exchange (ETDEWEB)

    Frank, M.V.

    1980-09-01

    STEFINS (STEel Freezing INtegral Simulation) is a computer program for the calculation of the rate of solidification of molten steel on solid steel. Such computations arize when investigating core melt accidents in fast reactors. In principle this problem involves a coupled two-dimensional thermal and hydraulic approach. However, by physically reasonable assumptions a decoupled approach has been developed. The transient solidification of molten steel on a cold wall is solved in the direction normal to the molten steel flow and independent from the solution for the molten steel temperature and Nusselt number along the direction of flow. The solutions to the applicable energy equations have been programmed in cylindrical and slab geometries. Internal gamma heating of steel is included.

  1. 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.

  2. Mechanical characteristics of fused cast basalt tube encased in steel pipe for protecting steel surface

    Institute of Scientific and Technical Information of China (English)

    Jee-Seok WANG; Jong-Do KIM; Hee-Jong YOON

    2009-01-01

    Because of the various excellent characteristics of cast basalt materials, such as, anti-corrosion, anti-wearing, good hardness, high chemical stability, of which steel may not possess, the steel-basalt composite pipes are used in severe environments for compensating the defects of steel. The limit of bending moment with which steel-basalt composite pipe may safely endure was calculated and the limit curvature of the composite pipe in the safe range was presented. The application temperature of steel-basalt pipe was examined due to a different coefficient among basalt, mortar and mild steel.

  3. pH-control modes in a 5-L stirred-tank bioreactor for cell biomass and exopolysaccharide production by Tremella fuciformis spore.

    Science.gov (United States)

    Zhu, Hu; Cao, Chunxu; Zhang, Shuaishuai; Zhang, Yan; Zou, Weisheng

    2011-10-01

    The effect of pH-control modes on cell growth and exopolysaccharide production by Tremella fuciformis was evaluated in a 5-L bioreactor. The results show that the maximal dry cell weight (DCW) and exopolysaccharide production were 23.57 and 4.48 g L⁻¹ in pH-stat fermentation, where the maximal specific growth rate (μ(max)) and specific production rate of exopolysaccharide (P(P/X)) were 1.03 and 0.24 d⁻¹, respectively; under pH-shift cultivation, the maximal DCW and exopolysaccharide production were 30.57 and 3.90 g L⁻¹, where the μ(max) and P(P/X) were 1.21 and 0.06 d⁻¹. Unlike batch fermentation, maximal DCW and exopolysaccharide production merely reached 15.04 and 2.0 g L⁻¹, where the μ(max) and P(P/X) were 0.86 and 0.05 d⁻¹, respectively. These results suggest that a pH-stat strategy is a more efficient way of performing the fermentation process to increase exopolysaccharide production. Furthermore, this research has also proved that the three-stage pH-control mode is effective for cell growth.

  4. Detection of gamma-rays with a 3.5 l liquid xenon ionization chamber triggered by the primary scintillation light

    CERN Document Server

    Aprile, E; Chen Dan Li; Muhkerjee, R; Xu Fan

    2002-01-01

    A gridded ionization chamber with a drift length of 4.5 cm and a total volume of 3.5 l, was operated with high-purity liquid xenon and extensively tested with gamma-rays from sup 1 sup 3 sup 7 Cs, sup 2 sup 2 Na and sup 6 sup 0 Co radioactive sources. An electron lifetime in excess of 1 ms was inferred from two independent measurements. The electric field dependence of the collected charge and energy resolution was studied in the range 0.1-4 kV/cm, for different gamma-ray energies. With an electric field of 4 kV/cm, the spectral performance of the detector is consistent with an energy resolution of 5.9% at 1 MeV, scaling with energy as E sup - sup 0 sup . sup 5. The chamber was also used to detect the primary scintillation light produced by gamma-ray interactions in liquid xenon. The light signal was successfully used to trigger the acquisition of the charge signal with a FADC readout. A trigger efficiency of approx 85% was measured at 662 keV.

  5. Pengaruh Variasi Goresan Lapis Lindung Dan Variasi pH Tanah Terhadap Arus Proteksi Sistem Impressed Current Cathodic Protection (ICCP Pada Pipa API 5L Grade B

    Directory of Open Access Journals (Sweden)

    Trendy Leo Pratama

    2015-03-01

    Full Text Available Korosi merupakan penyebab utama terjadinya kegagalan material pipeline akibat berinteraksi secara langsung dengan lingkungan. Pemberian lapis lindung yang selama ini menjadi pilihan utama untuk mengontrol korosi tidak selamanya bisa diandalkan. Hal ini disebabkan kemungkinan terjadinya kerusakan lapis lindung selama proses shipping atau instalasi sangatlah besar. Oleh karena itu sering kali pemberian lapis lindung dikolaborasikan dengan perlindungan sistem proteksi katodik, khususnya sistem arus paksa (ICCP. Penelitian ini bertujuan mempelajari pengaruh luas goresan lapis lindung dan pH tanah terhadap arus proteksi sistem proteksi katodik arus paksa (ICCP. Goresan yang diberikan berbentuk lingkaran dan persegi panjang dengan luas 10 mm2, 50 mm2, 100 mm2, 150 mm2, 250 mm2, dan 500 mm2. Spesimen tanpa goresan dan tanpa lapis lindung digunakan sebagai pembanding. Sedangkan untuk variasi pH tanahnya adalah pH 3 (asam, pH 7 (netral, dan pH 11 (basa. Pipa API 5L grade B digunakan sebagai katoda dan grafit sebagai anoda, serta rectifier sebagai penyearah arus (DC. Arus proteksi ICCP diatur hingga mencapai nilai potensial proteksi -850 mV vs elektroda Cu/CuSO4. Setelah dilakukan pengkondisian awal selama 8 hari dan 7 hari pengukuran arus, didapatkan hasil bahwa semakin semakin besar goresan lapis lindung maka semakin besar arus proteksi yang dibutuhkan dalam kondisi pH tanah yang sama. Sedangkan dalam kondisi luas goresan yang sama, kebutuhan arus proteksi meningkat seiring dengan semakin rendahnya pH tanah (semakin asam

  6. Occurrence and palaeoenvironmental significance of aromatic hydrocarbon biomarkers in Oligocene sediments from the Mallik 5L-38 Gas Hydrate Production Research Well (Canada)

    Energy Technology Data Exchange (ETDEWEB)

    Haberer, R.M.; Mangelsdorf, K.; Wilkes, H.; Horsfield, B. [Geoforschungszentrum Potsdam, Potsdam (Germany)

    2006-07-01

    The aromatic hydrocarbon biomarker distributions of thirty Oligocene sediment samples with different lithology (lignite, clay and sand) from the JAPEX/JNOC/GSC et al. Mallik 5L-38 Gas Hydrate Production Research Well, Canada, were analyzed using gas chromatography-mass spectrometry (GC-MS). The compositions vary with lithology, indicating a change in palaeoenvironmental conditions at the time of deposition. Aromatic diterpenoids of the abietane type are more abundant in the lignite samples than in the clay samples and represent a gymnosperm (e.g., conifer) dominated palaeovegetation. In contrast, in the clay samples aromatic triterpenoids are generally preserved as major constituents, indicating angiosperm dominated vegetation. The sand samples contain only minor amounts of aromatic terpenoids, but show a preference for diterpenoid gymnosperm markers. To recognise gymnosperm versus angiosperm dominated palaeoenvironments a new ratio, termed the angiosperm-gymnosperm aromatic ratio (AGAR), has been developed. Thus, the terpenoid distribution in the deltaic sediments provides information on the compositional changes in the plant community at the Mallik site (lignites) and the hinterland (clays) over time. Concomitantly, the changing dominance in the plant communities allows an insight into varying climatic conditions during the late Oligocene in the area.

  7. Development and validation of a real time PCR for the detection of myxoma virus based on the diploid gene M000.5L/R.

    Science.gov (United States)

    Duarte, Margarida Dias; Barros, Sílvia Carla; Henriques, Ana Margarida; Fagulha, Maria Teresa; Ramos, Fernanda; Luís, Tiago; Fevereiro, Miguel

    2014-02-01

    The myxoma virus (MYXV) causes severe infections in European rabbits that may reach mortality rates up to 100% depending on the viral strain. The typical symptoms and lesions induced by the virus are usually enough to permit the correct clinical diagnosis. However, in peracute forms the infection may be accompanied by unspecific symptoms. Sudden death may also occur without evident clinical signs of myxomatosis. Likewise, a clinical diagnosis of atypical forms of myxomatosis (amyxomatous) is often complicated and delayed due to the scarceness of skin lesions. As the disease control often depends on an early and unequivocal diagnosis of MYXV, laboratorial methods play a relevant role in the confirmation of MYXV infection. This study describes the development and validation of a novel, high accurate real time polymerase chain reaction assay (rtPCR) for the detection of MYXV. Primers were designed to amplify a 125-bp within the gene M000.5L/R, which is duplicated in the termini of the genome and is unique among Leporipoxvirus. The assay was negative for SFV and other poxviruses and was able to detect 2.6 copies of MYXV DNA proving the effectiveness, specificity and sensitivity of this diagnosis tool. The rtPCR has been applied successfully in INIAV laboratory for routine diagnosis of myxomatosis since 2005. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Bimetallic layered castings alloy steel – carbon cast steel

    Directory of Open Access Journals (Sweden)

    T. Wróbel

    2011-01-01

    Full Text Available In paper is presented technology of bimetallic layered castings based on founding method of layer coating directly in cast processso-called method of mould cavity preparation. Prepared castings consist two fundamental parts i.e. bearing part and working part (layer. The bearing part of bimetallic layered casting is typical foundry material i.e. ferritic-pearlitic carbon cast steel, whereas working part (layer is plate of austenitic alloy steel sort X10CrNi 18-8. The ratio of thickness between bearing and working part is 8:1. The quality of the bimetallic layered castings was evaluated on the basis of ultrasonic NDT (non-destructive testing, structure and macro- and microhardness researches.

  9. Study of pitting corrosion in line-pipe steel under the influence of remanent magnetization

    Energy Technology Data Exchange (ETDEWEB)

    Espina-Hernandez, J.H.; Caleyo, F.; Hallen, J.M. [Instituto Politecnico Nacional (IPN), Zacatenco (Mexico)

    2009-07-01

    The influence of remanent magnetization on pitting corrosion in line-pipe steels is studied. Pitting corrosion experiments have been carried out on samples of an API 5L grade 52 steel under a magnetization level of the same order of magnitude of the remanent magnetization in the pipeline wall after in-line inspection based on magnetic flux leakage. The samples were magnetized using rings of the same grade as the investigated steel. Immediately after magnetization, the investigated samples were subjected to pitting by immersing them in a solution containing dissolved Cl{sup -} and SO{sup 2-}{sub 4} and ions. The pitting experiments were conducted during a seven days period. The pit depth distribution and the maximum pit depth in each sample were recorded and used to conduct extreme value analyses of the pitting process in magnetized and non-magnetized control samples. The statistical assessment of the pitting corrosion data collected during this study shows that the magnetic field reduces the average depth of the pit population and also the extreme pit depth values that can be predicted from the maximum values observed in the magnetized samples in comparison with to the non-magnetized control samples. Scanning electron microscopy observations show that the magnetic field alters the pit morphology by increasing the pit mouth opening. (author)

  10. Theoretical and Experimental on Carbon Dioxide Sequestration Degree of Steel Slag

    Institute of Scientific and Technical Information of China (English)

    LI Jian-li; ZHANG Hui-ning; XU An-jun; CUI Jian; HE Dong-feng; TIAN Nai-yuan

    2012-01-01

    The limitation and experimental CO2 sequestration degree of steel slag is the focus. The theoretical and the practical COe sequestration degree was assessed under mild operating conditions. After calculation in theory, it can be found that the CO2 sequestration limitation degree for every kilogram steel slag is about 442 g when taking magne- sium into consideration, and the experimental CO2 sequestration degree for every kilogram slag is about 77 g, under the conditions that the liquid to solid ratio is 50 L/kg, CO2 flow is 0.5 L/min and the temperature of reaction is the ambient temperature. When solution NH4Cl and CHa COOH for experiments and other conditions keep the same, the actual potential CO2 sequestration for every kilogram slag is 69.3 g and 31.20 g respectively. Thus, optimization of process parameters like granularity of slag is necessary to enhance the carbon dioxide sequestration degree for steel slag.

  11. Study of pitting corrosion in line-pipe steel under the influence of remanent magnetization

    Energy Technology Data Exchange (ETDEWEB)

    Espina-Hernandez, J.H.; Caleyo, F.; Hallen, J.M. [Instituto Politecnico Nacional (IPN), Zacatenco (Mexico)

    2009-07-01

    The influence of remanent magnetization on pitting corrosion in line-pipe steels is studied. Pitting corrosion experiments have been carried out on samples of an API 5L grade 52 steel under a magnetization level of the same order of magnitude of the remanent magnetization in the pipeline wall after in-line inspection based on magnetic flux leakage. The samples were magnetized using rings of the same grade as the investigated steel. Immediately after magnetization, the investigated samples were subjected to pitting by immersing them in a solution containing dissolved Cl{sup -} and SO{sup 2-}{sub 4} and ions. The pitting experiments were conducted during a seven days period. The pit depth distribution and the maximum pit depth in each sample were recorded and used to conduct extreme value analyses of the pitting process in magnetized and non-magnetized control samples. The statistical assessment of the pitting corrosion data collected during this study shows that the magnetic field reduces the average depth of the pit population and also the extreme pit depth values that can be predicted from the maximum values observed in the magnetized samples in comparison with to the non-magnetized control samples. Scanning electron microscopy observations show that the magnetic field alters the pit morphology by increasing the pit mouth opening. (author)

  12. Multicomponent Synthesis and Evaluation of New 1,2,3-Triazole Derivatives of Dihydropyrimidinones as Acidic Corrosion Inhibitors for Steel

    Directory of Open Access Journals (Sweden)

    Rodrigo González-Olvera

    2016-02-01

    Full Text Available An efficient one-pot synthesis of 1,2,3-triazole derivatives of dihydropyrimidinones has been developed using two multicomponent reactions. The aldehyde-1,2,3-triazoles were obtained in good yields from in situ-generated organic azides and O-propargylbenzaldehyde. The target heterocycles were synthesized through the Biginelli reaction in which the aldehyde-1,2,3-triazoles reacted with ethyl acetoacetate and urea in the presence of Ce(OTf3 as the catalyst. The corrosion inhibition of steel grade API 5 L X52 in 1 M HCl by the synthesized compounds was investigated using the electrochemical impedance spectroscopy technique. The measurements revealed that these heterocycles are promising candidates to inhibit acidic corrosion of steel.

  13. Multicomponent Synthesis and Evaluation of New 1,2,3-Triazole Derivatives of Dihydropyrimidinones as Acidic Corrosion Inhibitors for Steel.

    Science.gov (United States)

    González-Olvera, Rodrigo; Román-Rodríguez, Viridiana; Negrón-Silva, Guillermo E; Espinoza-Vázquez, Araceli; Rodríguez-Gómez, Francisco Javier; Santillan, Rosa

    2016-02-22

    An efficient one-pot synthesis of 1,2,3-triazole derivatives of dihydropyrimidinones has been developed using two multicomponent reactions. The aldehyde-1,2,3-triazoles were obtained in good yields from in situ-generated organic azides and O-propargylbenzaldehyde. The target heterocycles were synthesized through the Biginelli reaction in which the aldehyde-1,2,3-triazoles reacted with ethyl acetoacetate and urea in the presence of Ce(OTf)₃ as the catalyst. The corrosion inhibition of steel grade API 5 L X52 in 1 M HCl by the synthesized compounds was investigated using the electrochemical impedance spectroscopy technique. The measurements revealed that these heterocycles are promising candidates to inhibit acidic corrosion of steel.

  14. Bond characteristics of steel fiber and deformed reinforcing steel bar embedded in steel fiber reinforced self-compacting concrete (SFRSCC)

    Science.gov (United States)

    Aslani, Farhad; Nejadi, Shami

    2012-09-01

    Steel fiber reinforced self-compacting concrete (SFRSCC) is a relatively new composite material which congregates the benefits of the self-compacting concrete (SCC) technology with the profits derived from the fiber addition to a brittle cementitious matrix. Steel fibers improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibers on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fiber and SCC firstly. Based on the available experimental results, the current analytical steel fiber pullout model (Dubey 1999) is modified by considering the different SCC properties and different fiber types (smooth, hooked) and inclination. In order to take into account the effect of fiber inclination in the pullout model, apparent shear strengths (τ (app)) and slip coefficient (β) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle (ϕ). Furthurmore, steel-concrete composite floors, reinforced concrete floors supported by columns or walls and floors on an elastic foundations belong to the category of structural elements in which the conventional steel reinforcement can be partially replaced by the use of steel fibers. When discussing deformation capacity of structural elements or civil engineering structures manufactured using SFRSCC, one must be able to describe thoroughly both the behavior of the concrete matrix reinforced with steel fibers and the interaction between this composite matrix and discrete steel reinforcement of the conventional type. However, even though the knowledge on bond behavior is essential for evaluating the overall behavior of structural components containing reinforcement and steel fibers

  15. Longer Life for Steel Structures

    Science.gov (United States)

    1990-01-01

    IC 531 is a coating manufactured and marketed by Inorganic Coatings, Inc. The coating was developed by Goddard to protect structures at Kennedy Space Center. It is a high ratio potassium silicate formula. The coating is water based, nontoxic, and nonflammable. It generates no volatile organic compounds nor hazardous chemical waste, and bonds to steel in 30 minutes. At the present time, no one can say for sure how long IC 531's effective lifetime is. Some of the original Goddard test applications of 1976 are still going strong after lengthy exposure to the Sun, salt and moisture. Says IC in company literature: 'IC 531 offers virtually permanent protection for steel. We predict it will protect structures for well beyond 25 years. If necessary, it is infinitely maintainable; if damaged, it can easily be touched up with more IC 531.'

  16. Existing Steel Railway Bridges Evaluation

    Science.gov (United States)

    Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter

    2016-12-01

    The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  17. New Application of Stainless Steel

    Institute of Scientific and Technical Information of China (English)

    YANG Jia-long; LI Ying; WANG Fu; ZANG Zheng-gui; LI Si-jun

    2006-01-01

    Several rigid substrates such as stainless steel, titanium alloy, aluminum alloy, nickel foil, silicon, and sodium lime glass have been employed for manufacturing high quality TiO2 films by metal organic chemical vapor deposition (MOCVD). The as-deposited TiO2 films have been characterized with SEM/EDX and XRD. The photocatalytic properties were investigated by decomposition of aqueous orangeⅡ. UV-VIS photospectrometer was employed to check the absorption characteristics and photocatalytic degradation activity. The results show that films synthesized on metal substrates display higher photoactivities than that on absolute substrates such as silicon and glass. It is found that solar light is an alternative to UV-light used for illumination during photodegradation of orange Ⅱ. TiO2 film on stainless steel substrate was regarded as the best one for photocatalysis.

  18. Fatigue Strength of Weathering Steel

    Directory of Open Access Journals (Sweden)

    Ludvík KUNZ

    2012-03-01

    Full Text Available Fatigue behaviour of Atmofix 52 steel (comparable to COR-TENâ steel exposed to atmospheric corrosion for 20 years was investigated. S-N curves for load symmetrical cycling and cycling with stress ratio R = 0 were determined on specimens detracted from a failed transmission tower. The data were compared with those on material without a rust layer. The fracture surfaces and, in particular, the sites of fatigue crack initiation were analyzed. Substantial decrease of fatigue life and fatigue limit due to corrosion exposition was found. Based on observation of surface layer with corrosion products and on fractographic analysis of failed specimens conclusions on fatigue damage mechanism were drawn. No grain boundary corrosion, which can be responsible for fatigue crack initiation, was observed. Initiation of fatigue cracks was related to surface roughness and took place exclusively on corrosion dimples.DOI: http://dx.doi.org/10.5755/j01.ms.18.1.1335

  19. Complement Receptors C5aR and C5L2 Are Associated with Metabolic Profile, Sex Hormones, and Liver Enzymes in Obese Women Pre- and Postbariatric Surgery

    Directory of Open Access Journals (Sweden)

    Reza Rezvani

    2014-01-01

    Full Text Available Objective. Obesity is associated with metabolic dysfunction with sex differences and chronic, low-grade inflammation. We proposed that hepatic expression of immune complement C3 related receptors (C3aR, C5aR, and C5L2 would be associated with pre- or postmenopausal status and metabolic profile in severely obese women. We hypothesized that C5L2/C5aR ratio, potentially influencing the ASP/C5L2 metabolic versus C5a/C5aR immune response, would predict metabolic profiles after weight loss surgery. Materials and Methods. Fasting plasma (hormone, lipid, and enzyme analysis and liver biopsies (RT-PCR gene expression were obtained from 91 women during surgery. Results. Hepatic C5L2 mRNA expression was elevated in pre- versus postmenopausal women (P<0.01 and correlated positively with circulating estradiol, estrone, ApoB, ApoA1, ApoA1/B, waist circumference, age, and LDL-C (all P<0.05. While plasma ASP was lower in pre- versus postmenopausal women (P<0.01, the hepatic C5L2/C5aR mRNA ratio was increased (P<0.001 and correlated positively with estrone (P<0.01 and estradiol (P<0.001 and negatively with circulating ApoB and liver enzymes ALT, AST, and GGT (all P<0.05. Over 12 months postoperatively, liver enzymes in low C5L2/C5aR mRNA ratio group remained higher (ALP and ALT, P<0.05, AST and GGT, P<0.001 2-way-ANOVA. Conclusion. C5L2-C5aR association with other mediators including estrogens may contribute to hepatic metabolic and inflammatory function.

  20. High Fragmentation Steel Production Process

    Science.gov (United States)

    1984-01-01

    processes which might result in anamolies and to use the data to establish processing parameters for forging and machining operations. The first...from different vendors to investigate these variations. Another concern of this phase was the cooling method used by steel producers in the event of...10% coarse pearlite. There were no vivid white spots (which would indicate preci- pitated carbides) detected on the sample. The hardness and

  1. Benchmarking in Mobarakeh Steel Company

    OpenAIRE

    Sasan Ghasemi; Mohammad Nazemi; Mehran Nejati

    2008-01-01

    Benchmarking is considered as one of the most effective ways of improving performance in companies. Although benchmarking in business organizations is a relatively new concept and practice, it has rapidly gained acceptance worldwide. This paper introduces the benchmarking project conducted in Esfahan's Mobarakeh Steel Company, as the first systematic benchmarking project conducted in Iran. It aims to share the process deployed for the benchmarking project in this company and illustrate how th...

  2. Benchmarking in Mobarakeh Steel Company

    Directory of Open Access Journals (Sweden)

    Sasan Ghasemi

    2008-05-01

    Full Text Available Benchmarking is considered as one of the most effective ways of improving performance incompanies. Although benchmarking in business organizations is a relatively new concept and practice, ithas rapidly gained acceptance worldwide. This paper introduces the benchmarking project conducted in Esfahan’s Mobarakeh Steel Company, as the first systematic benchmarking project conducted in Iran. It aimsto share the process deployed for the benchmarking project in this company and illustrate how the projectsystematic implementation led to succes.

  3. Metadynamic recrystallization in C steels

    Indian Academy of Sciences (India)

    A R Morgridge

    2002-08-01

    Metadynamic recrystallization has been investigated in three plain carbon steels (ENIA, EN2 and EN24) through the use of hot interrupted compression tests on a wedge plastometer. Holding time was 0.5 s between passes. Strain rates of 0.05 and 0.12/s and small strain increments of 3, 5 and 7% were employed. Test temperatures were varied between 800 and 1100°C. Various incremental and continuous stress strain curves were highlighted at different temperatures and strain rates for 3 steels, ENIA, EN2 and EN24, resulting in varying flow stresses and strains. Highest peak stress was 180 MPa for EN24 at peak strain of 0.25 and 900°C, with a strain rate 0.12/s. Peak strain values for all steels at 1100°C was 0.133 at a strain rate of 0.05/s and 0.15 at a strain rate of 0.12/s. Strain accumulation resulted in dynamic and metadynamic recrystallization with refinement to about 15 m for dynamic and 22 m for metadynamic recrystallization. Fractional softening, , decreased from 0.27 to 0.12 as recrystallization times in metadynamic recrystallization increased from 0.9 s to 1.5 s at 1100°C. Time for 50% metadynamic recrystallization was also reduced as temperature increased. For ENIA, a drop from 10000 s to 20 s, as temperature increased from 800 to 1100 °C was observed. For EN24 and EN2 steels, a drop from 4000 s to 6 s for similar temperature rise was observed. Metadynamic recrystallization (at strains higher than critical strain) is observed to be a strong function of strain rate and a very weak function of temperature and strain. It significantly refined the austenite grain size prior to transformation.

  4. Corrosion of mild steel and stainless steel by marine Vibrio sp.

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhaDevi; Wagh, A.B.

    Microbially induced corrosion (MIC) of stainless steel and mild steel coupons exposed to media with and without a bacterial culture Vibrio sp. was studied using Scanning Electron Microscope (SEM). Pitting type of corrosion was noticed which was more...

  5. The new 2.5L L4 gasoline engine for LEXUS IS300h. The renewed engine series for FR hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Ishiguro, Fumihisa; Mashiki, Zenichiro; Yamanari, Kenji [Toyota Motor Corporation, Aichi (Japan)

    2013-08-01

    To ensure future sustainable mobility, vehicles have to face crucial problems such as energy security, global warming and air quality. To address these problems, TOYOTA introduced in 1997 the TOYOTA Hybrid System (THS) and has continuously improved its technology, globally contributing to the environmental improvement by its expansion into many markets in the world. TOYOTA presented the renewed 4 Cylinder Engine Series for FF vehicles at this symposium last year. This year, Toyota presents the result of its continuous development for FR Hybrid Vehicles, especially for D and E segment vehicles. Toyota not only improved thermal efficiency and reduced CO{sub 2} but also achieved high power output. In 2012, TOYOTA launched 3.5L V6 engine for LEXUS-GS (2GR-FXE engine), as first engine of this new engine series. In 2013, TOYOTA will launch 2.5L-L4 engine for LEXUS-IS (2AR-FSE engine), as the leading engine of this series. Toyota developed these new engines, aiming at leadership with regard to fuel economy, clean exhaust gas and high reliability. Toyota carried out modifications, taking into account usage of Hybrid System. With targeting highest levels of environmental performance, Toyota improved the vehicle driving performances like acceleration response by the combination of enhanced engine power output and newly developed Hybrid System. One of the biggest feature of this series is new generation D-4S system, including two injectors (for Direct injection and Port injection) for each cylinder, high fuel pressure (greater than 18MPa) and high fuel flow rate. The new generation D-4S system helps achieving high performance and good thermal efficiency. Furthermore, Toyota added on Cooled EGR system to 2AR-FSE engine, contributing to lower the fuel consumption, especially in highway driving. The very low friction technology and the well proven Atkinson Cycle are also key features of this engine series. Thanks to the above features, the new engine series achieves high

  6. 77 FR 67400 - RG Steel Wheeling, LLC, a Division of RG Steel, LLC, Doing Business as Wheeling Corrugating...

    Science.gov (United States)

    2012-11-09

    ... Employment and Training Administration RG Steel Wheeling, LLC, a Division of RG Steel, LLC, Doing Business as..., 2012, applicable to workers of RG Steel Wheeling, LLC, a division of RG Steel, LLC, doing business as... RG Steel, LLC, doing business as Wheeling Corrugating Company, Beech Bottom, West Virginia,...

  7. Nickel: makes stainless steel strong

    Science.gov (United States)

    Boland, Maeve A.

    2012-01-01

    Nickel is a silvery-white metal that is used mainly to make stainless steel and other alloys stronger and better able to withstand extreme temperatures and corrosive environments. Nickel was first identified as a unique element in 1751 by Baron Axel Fredrik Cronstedt, a Swedish mineralogist and chemist. He originally called the element kupfernickel because it was found in rock that looked like copper (kupfer) ore and because miners thought that "bad spirits" (nickel) in the rock were making it difficult for them to extract copper from it. Approximately 80 percent of the primary (not recycled) nickel consumed in the United States in 2011 was used in alloys, such as stainless steel and superalloys. Because nickel increases an alloy's resistance to corrosion and its ability to withstand extreme temperatures, equipment and parts made of nickel-bearing alloys are often used in harsh environments, such as those in chemical plants, petroleum refineries, jet engines, power generation facilities, and offshore installations. Medical equipment, cookware, and cutlery are often made of stainless steel because it is easy to clean and sterilize. All U.S. circulating coins except the penny are made of alloys that contain nickel. Nickel alloys are increasingly being used in making rechargeable batteries for portable computers, power tools, and hybrid and electric vehicles. Nickel is also plated onto such items as bathroom fixtures to reduce corrosion and provide an attractive finish.

  8. Analisa Pengaruh Variasi Sudut Bevel Akibat Kombinasi Pengelasan Fcaw dan SMAW terhadap Kekuatan Impact Butt Joint pada Spesimen Pipa Api 5l Grade X42

    Directory of Open Access Journals (Sweden)

    Rizkiyah Ramadani

    2017-01-01

    Full Text Available Kekuatan sambungan las pada suatu konstruksi perlu diperhatikan dengan baik dan pengujian pun perlu dilakukan untuk mengetahui ketahanan bahan terhadap suatu beban. Dalam penelitian tugas akhir ini bertujuan untuk mengetahui pengaruh sudut bevel dan kondisi optimal akibat  kombinasi pengelasan FCAW dan SMAW terhadap kekuatan impact butt joint pada material pipa API 5L grade X42. Variasi sudut bevel yang digunakan adalah 60o, 40o, dan 0o. Pengujian impact merupakan suatu upaya untuk mensimulasikan kondisi operasi material yang sering ditemui dalam perlengkapan transportasi atau konstruksi dimana beban tidak selamanya terjadi secara perlahan-lahan melainkan datang secara tiba-tiba, khususnya dalam konstruksi bangunan lepas pantai dimana beban secara tiba – tiba sangat memungkinkan untuk terjadi. Dari hasil penelitian yang dilakukan didapatkan bahwa  nilai kekuatan impact pada sudut bevel 60o di bagian weld adalah sebesar 2.01 J/mm2 dan bagian HAZ sebesar 2.08  J/mm2. Sudut bevel 40o memiliki nilai pada bagian weld sebesar 2.10 J/mm2 dan bagian HAZ sebesar 2.13  J/mm2. Namun memiliki pengaruh yang jauh berbeda dengan sudut bevel 0o yaitu memiliki nilai impact sebesar 1.72 J/mm2 untuk bagian weld dan 1.13 J/mm2 untuk bagian HAZ . Kondisi optimal pengaruh sudut bevel terhadap kekutan impact adalah sudut 40o . Hal ini dikarenakan persentase ferrite metalografi struktur mikronya lebih banyak dibandingkan dengan sudut bevel 60o dan 0o dan juga memiliki nilai kekerasan yang rendah sehingga bersifat ulet menyebabkan nilai impact-nya lebih unggul. Selain itu efisensi dalam segi penghematan waktu kerja, perkerja maupun biaya produksi lebih baik.

  9. Predicting EuroQoL 5 Dimensions 5 Levels (EQ-5D-5L) Utilities from Older People's Quality of Life Brief Questionnaire (OPQoL-Brief) Scores.

    Science.gov (United States)

    Kaambwa, Billingsley; Ratcliffe, Julie

    2017-06-16

    Economic evaluation of healthcare treatment and services targeted at older people requires measurement of utility-based quality-of-life outcomes but it is not always possible to collect such outcome data. It may, however, be possible to estimate these outcomes using non-utility measures of quality of life where the latter have been collected. The objective of this study was to develop a regression-based algorithm to map a non-utility-based outcome, the Older People's Quality of Life brief questionnaire (OPQoL-brief), onto a utility-based outcome, the EuroQoL 5 Dimensions 5 Levels (EQ-5D-5L). The estimation sample comprised 330 community-based Australian older people (>65 years), while the validation sample consisted of 293 older people from a separate study. Six regression techniques were employed to estimate utilities from OPQoL-brief. The predictive accuracy of 54 regression models (six regression techniques × nine model specifications) was assessed using six criteria: mean absolute error (MAE), root mean squared error (RMSE), correlation, distribution of predicted utilities, distribution of residuals, and proportion of predictions with absolute errors brief items were included as continuous variables (OLS 4). RMSE and MAE estimates for this model (0.2201 and 0.1638, respectively) were within the range of published estimates. It is possible to predict valid utilities from OPQoL-brief using regression methods. We recommend OLS model (4) for this exercise.

  10. Strengthening of nitrogen-containing maraging steels

    Energy Technology Data Exchange (ETDEWEB)

    Kaputkina, L.M.; Prokoshkina, V.G.; Uluntsev, D.Yu. [Moskovskij Inst. Stali i Splavov, Moscow (Russian Federation)

    1999-07-01

    The austenitic and austenitic-martensitic aging 15Cr(5-10)Ni2CuMoV(Nb)Ti-N - based steels were elaborated and investigated. These steels combine advantages of austenitic and martensitic steels and allow wide variety of phase compositions and mechanical properties. For nitrogen-containing austenitic and austenitic-martensitic steels it is possible to achieve, due to stress-induced martensitic transformation and thermomechanical treatment optimization, the strength level of martensitic-austenitic steels in a combination with high plasticity and fracture toughness inherent in pure austenitic structures. At the same time corrosion resistance of these steels in low-aggressive media is preserved and wear resistance increases as twice. (orig.)

  11. Austenitic Oxide Dispersion Strengthened Steels : A Review

    Directory of Open Access Journals (Sweden)

    Lavanya Raman

    2016-06-01

    Full Text Available Materials play an important role in the fast breeder reactors.  Materials used in cladding tube and fuel pins should have better creep and void swelling resistance. To overcome these difficulties, a new class of material known as oxide dispersion strengthened (ODS steels are used. There are two groups of ODS steels, the ferritic and the austenitic ODS steels based on the matrix. The present paper reviews the current status of research in austenitic ODS steels. The interaction of dislocations with finely dispersed incoherent, hard particles that governs the strength and high temperature properties of ODS materials is briefly reviewed. The synthesis route adopted for these ODS steels, which is mostly through powder metallurgy route is also discussed. The role of various oxides such as Y2O3, ZrO2and TiO2and the clusters formed in these ODS steels on the mechanical properties and void swelling characteristics is also discussed.

  12. Development and outlook of Chinese steel industry

    Institute of Scientific and Technical Information of China (English)

    LIU; Liu

    2005-01-01

    The fast development of Chinese steel industry has drawn great attention from the world.Market n eeding and technical development are the main driving forces for the rapid development of Chinese steel industry. Based on the discussing of the reasons of its rapid development, the present paper further analyzed the main problems and distance towards the advanced level of international steel industry. It bring forward that Chinese steel industry should enhance the research and development on new generation steel materials and production process to ensure its sustainable development. Through populating the key technologies of syntheses energy saving and water saving to realize the main equipments self-making and establish a new recyclable steel production process.

  13. 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.

  14. Utilization of structural steel in buildings.

    Science.gov (United States)

    Moynihan, Muiris C; Allwood, Julian M

    2014-08-01

    Over one-quarter of steel produced annually is used in the construction of buildings. Making this steel causes carbon dioxide emissions, which climate change experts recommend be reduced by half in the next 37 years. One option to achieve this is to design and build more efficiently, still delivering the same service from buildings but using less steel to do so. To estimate how much steel could be saved from this option, 23 steel-framed building designs are studied, sourced from leading UK engineering firms. The utilization of each beam is found and buildings are analysed to find patterns. The results for over 10 000 beams show that average utilization is below 50% of their capacity. The primary reason for this low value is 'rationalization'-providing extra material to reduce labour costs. By designing for minimum material rather than minimum cost, steel use in buildings could be drastically reduced, leading to an equivalent reduction in 'embodied' carbon emissions.

  15. Coating of a steel wire with copper

    Science.gov (United States)

    Vdovin, K. N.; Dubskii, G. A.; Nefed'ev, A. A.; Derevyanko, D. V.

    2016-03-01

    The process of coating of a steel wire with liquid copper at a high speed (>1 m/s) is considered. The results of long-term studies of copperizing under laboratory conditions and electron-microscopic investigation of the copper-steel adhesion are used to develop a mathematical model for coating of a steel wire with copper and to create a commercial setup to implement this process.

  16. Experimental studies of Steel Corrugated Constructions

    Directory of Open Access Journals (Sweden)

    Lazarev Yuriy

    2016-01-01

    Full Text Available The purpose of this particular article is to assess existing calculations of steel corrugated constructions. Steel Corrugated Construction is a perspective type of constructions, which is exhibiting numerous advantages in comparison with one that currently applied in automobile and railroad networks (reinforced concrete water-throughput pipes, reinforced concrete frame bridges. The evaluation of experimental data on models of constructions of this particular type has been carried out in order to improve calculations of Steel Corrugated Constructions.

  17. Characteristics of vacuum sintered stainless steels

    OpenAIRE

    Z. Brytan; L.A. Dobrzański; M. Actis Grande; Rosso, M.

    2009-01-01

    Purpose: In the present study duplex stainless steels were sintered in vacuum. using rapid cooling form the mixture of prealloyed and alloying element powders The purpose of this paper was to describe the obtained microstructures after sintering as well as the main mechanical properties of sintered stainless steels.Design/methodology/approach: In presented work duplex stainless steels were obtained through powder metallurgy starting from austenitic 316L or ferritic 410L prealloyed stainless s...

  18. Kocel Steel Foundry Grand Opening Ceremony

    Institute of Scientific and Technical Information of China (English)

    TIAN Shi-jiang

    2006-01-01

    @@ On May 9, 2006 the Grand Opening ceremony of Kocel Steel Foundry Co., Ltd. was held in the National Economic and Technological Development Zone in Yinchuan City, Ningxia, China. Kocel Steel Foundry Co.,Ltd. is a large scale enterprise producing steel castings and it is jointly established by Ningxia Kocel Group,Changcheng Suzaki Machine & Foundry Co., Ltd. and Voestalpine Giesserei Linz GmbH, Austria.

  19. Evaluation of the Benefits of HSLA Steels

    Science.gov (United States)

    1989-03-01

    quenched and tempered steels , such as HY80 and HY1OO, require preheat and interpass temperature controls during welding of plates thicker than 1/2 inch...interpass tempera- tures and heat input limitations. Strict adherence to these requirements is mandatory to avoid cracking in hydrogen- sensitive steels ...requirement and excellent weldability of this steel will probably lower produc- tion costs and cracking -related repairs enough to overcome the slight

  20. Plate Rolling Modeling at Mill 5000 of OJSC ``Magnitogorsk Iron and Steel'' for Analysis and Optimization of Temperature Rates

    Science.gov (United States)

    Salganik, V.; Shmakov, A.; Pesin, A.; Pustovoytov, D.

    2010-06-01

    Modeling of strip deflected mode and thermal state in rolling is an integral part of the technology and perspective rolling-mill machinery such as plate mill 5000 of the OJSC "Magnitogorsk Iron and Steel". To comprehend metal behavior in the deformation zone in the rough passes during plate rolling it is essential to assess the impact of various temperature factors on variations in field of stress and strain intensities as well as temperature fields in deformation. To do such researches in consideration of various software products and adequate results one of the most effective methods nowadays is regarded as the method of finite elements. The research shows modeling of roughing rolling of a pipe steel sheet with strength category X80 according to standard API-5L. In the research of the metal deflected mode software product DEFORM 2D has been used for the isothermal and nonisothermic process. The mathematical modeling allows revealing the impact of temperature field on the metal deflected mode in the rough passes in plate rolling. Supposedly, it is deformation heating that can have more impact on the ingot temperature profile in the finishing passes in controlled rolling of the pipe steel grades. It is defined by high percent reduction, rolling speeds; more area of heat exchange surface; less thickness and lower temperature of rolling. The results can be used to develop efficient modes of plate rolling of the pipe steels.

  1. RATIONAL STEEL CORRUGATED PROFILE DESIGN

    Directory of Open Access Journals (Sweden)

    V. V. Kachurenko

    2015-08-01

    Full Text Available Purpose. The work sets forth the search results of new, more efficient design solutions for metal silos, namely, the analysis of existing types of profiles cross-section in a steel wall of such silo and development of less material-intensive section of corrugated profile.Methodology. To achieve the set goal there were researched the existing types of capacitive structure profiles and their strain-stress state under the load. The analysis was performed on the results of computational experiments. The prototype object was mathematical computer models. The calculations were made using the finite-element method. For computational experiment there was used the design-computing system Structure CAD for Windows. Findings. In this work there were obtained the data allowing to assess work of the profiles and to find more effective type of cross-section in terms of its material consumption. In the process of joint study of the authors a new type of profile for capacitive structures was developed; it has higher utilization efficiency and the attachment point of individual steel sheets with this type of profile. Both solutions are easy to install, reliable in operation and can be manufactured in the conditions of modern industrial production using standard equipment, materials and components. Originality. A new type of corrugated profile cross-section for steel silo walls was proposed; it has higher load carrying capacity and rigidity and allows reducing the metal thickness without changing the structure carrying capacity that results in material consumption reduction of the whole structure.For this and similar types of profiles there was designed and proposed the attachment point of individual corrugated sheets screwed with extending flange, which enables the unit connection in case of small size corrugations, where the distance is not sufficient to accommodate the bolt cap between the individual corrugations. Practical value.Application of the proposed

  2. Tribochemical interactions of boron carbides against steel

    Energy Technology Data Exchange (ETDEWEB)

    Gogotsi, Yu.G. (Univ. Karlsruhe, Inst. fuer Keramik im Maschinenbau (Germany)); Koval' chenko, A.M.; Kossko, I.A. (Inst. for Problems of Materials Science, Ukrainian Academy of Sciences, Kiev (Ukraine))

    1992-04-15

    Auger electron spectroscopy and electron microscopy were used to investigate the surface chemistry and tribological properties of boron carbide sliding against steel. It was revealed that the interacting process was accompanied by the diffusion of the ceramic elements into steel and by the oxidation of the steel and ceramic surfaces due to the oxygen presence in the atmosphere. It was established that the oxidation process in air or during friction tests leads to a graphitized layer on the boron carbide surface under the B{sub 2}O{sub 3} film. It was demonstrated that the oxidation caused a decrease in the friction coefficient of boron carbide sliding against steel. (orig.).

  3. Business Intelligence for Strategic Steel Constructions Sourcing

    DEFF Research Database (Denmark)

    Adeyemi, Oluseyi

    2010-01-01

    markets, government support for industry and stability of government}, to source steel constructions strategically. I undertook this project as a consultation for JB Contractors A/S {JBC} now referred to as Strongstaal A/S. JBC builds on its core competences in steel constructions, forgings, pressure...... vessels, welding, machining, heat treatment, corrosive treatment and quality control. It uses these core competencies to manufacture heavy duty, labour-intensive welded and machine processed steel structures in Eastern Europe. It has many years of sound project management experience and has enjoyed great...... success in performing both large and small integrated projects in the steel manufacturing industry and cement industry among others....

  4. Industrial investigations of the liquid steel filtration

    Directory of Open Access Journals (Sweden)

    K. Janiszewski

    2014-07-01

    Full Text Available Hitherto existing investigations concerning the ceramic filter use in the steel making processes have given good results. The obtained results of filtration have proved that this method may be used as an effective and cheap way of steel filtration from non-metallic inclusions. Placing filters in the tundish is the best location considering the limitation of the possibility of secondary pollution of steel. Yet, the results presented in this paper, of an experiment prepared and carried out in the industrial environment, are the only positive results obtained, which are connected with so much quantities of liquid steel processed with use of the multi-hole ceramic filters.

  5. Progress of Production Technology of Clean Steel in Baosteel

    Institute of Scientific and Technical Information of China (English)

    CuiJian

    2005-01-01

    The progress in control technology of carbon, nitrogen, total oxygen, phosphorus, and stdphur as well as inclusions in steel is discussed at Baosteel. The purity obtained in IF steel and pipeline steel is introduced.

  6. Experience with ferrosilicoaluminum alloy during deoxidation of steel

    Directory of Open Access Journals (Sweden)

    A. Mekhtiyev

    2015-10-01

    Full Text Available The article describes the process of deoxidation quiet and low-alloyed steel alloy ferrosilicoaluminum complex in comparison the existing, and with steel deoxidation technology with conventional alloys - ferrosilicon and secondary aluminum. A comparative analysis of quality steel, non-metallic inclusions metallographic studies and studies of the mechanical properties of the resulting steel was done. On a large array of experimental steel proved cost-effectiveness and feasibility of ferrosilicoaluminum during deoxidation quiet and low-alloyed steel.

  7. Effect of weld on design of steel moment-resisting connection reinforced with steel plates

    Institute of Scientific and Technical Information of China (English)

    CHEN Peng; LI Yong

    2005-01-01

    The foreign experimental and FEM research of steel moment-resisting connection reinforced with steel plates are introduced. The effect of weld on the connection design is studied in two ways including weld detail and geometrical detail of steel plates contrast to the reference drawing of connection design in China. The research shows that the weld plays an important role in the design of connections. The welds connecting reinforced plates and beam/ column flange and the plate geometry have direct influence on the performance of the connections reinforced with plates. The study is helpful to the application of design of steel moment-resisting connection with steel plates.

  8. CO{sub 2} corrosion resistance of carbon steel in relation with microstructure changes

    Energy Technology Data Exchange (ETDEWEB)

    Ochoa, Nathalie, E-mail: nochoa@usb.ve [Departamento de Ciencia de los Materiales, Universidad Simón Bolívar, Aptdo., 89000, Caracas (Venezuela, Bolivarian Republic of); Vega, Carlos [Departamento de Ciencia de los Materiales, Universidad Simón Bolívar, Aptdo., 89000, Caracas (Venezuela, Bolivarian Republic of); Pébère, Nadine; Lacaze, Jacques [Université de Toulouse, CIRIMAT, UPS/INPT/CNRS, ENSIACET, 4 Allée Emile Monso, CS 44362, 31030 Toulouse Cedex 4 (France); Brito, Joaquín L. [Laboratorio de Físico-química de Superficies, Centro de Química, Instituto Venezolano de Investigaciones Cientificas (IVIC), Carretera Panamericana, Km 11, Altos de Pipe, Estado Miranda (Venezuela, Bolivarian Republic of)

    2015-04-15

    The microstructural effects on the corrosion resistance of an API 5L X42 carbon steel in 0.5 M NaCl solution saturated with CO{sub 2} was investigated. Four microstructures were considered: banded (B), normalized (N), quenched and tempered (Q&T), and annealed (A). Electrochemical measurements (polarization curves and electrochemical impedance spectroscopy) were coupled with surface analyses (scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS)) to characterize the formation of the corrosion product layers. Electrochemical results revealed that corrosion resistance increased in the following order: B < N < Q&T < A. From the polarization curves it was shown that specifically, cathodic current densities were affected by microstructural changes. SEM images indicated that ferrite dissolved earlier than cementite and a thin layer of corrosion products was deposited on the steel surface. XPS analyses revealed that this layer was composed of a mixture of iron carbonate and non-dissolved cementite. It was also found that the quantity of FeCO{sub 3} content on the steel surface was greater for Q&T and A microstructures. These results, in agreement with the electrochemical data, indicate that the deposition mechanism of iron carbonate is closely related to the morphology of the non-dissolved cementite, determining the protective properties of the corrosion product layers. - Highlights: • The effect of change in microstructure on CO{sub 2} corrosion resistance was evaluated. • An API 5LX 42 carbon steel was immersed in a 0.5 M NaCl solution saturated with CO{sub 2}. • Banded, normalized, quenched-tempered and annealed microstructures were considered. • Electrochemical measurements were coupled with surface analysis. • Morphology and distribution of undissolved Fe{sub 3}C control corrosion kinetics.

  9. Mapping health-related quality of life scores from FACT-G, FAACT, and FACIT-F onto preference-based EQ-5D-5L utilities in non-small cell lung cancer cachexia.

    Science.gov (United States)

    Meregaglia, Michela; Borsoi, Ludovica; Cairns, John; Tarricone, Rosanna

    2017-09-25

    Health-related quality of life (HRQoL) measurements from disease-specific tools cannot be directly used in economic evaluations. This study aimed to develop and validate mapping algorithms that predicted EuroQol 5-Dimensions 5-Levels (EQ-5D-5L) utilities from Functional Assessment of Anorexia-Cachexia Therapy (FAACT) and Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) and their common component (Functional Assessment of Cancer Therapy-General-FACT-G) in patients with non-small cell lung cancer cachexia. Data were collected on five occasions over a 12-week period in two multicenter placebo-controlled trials. EQ-5D-5L utilities were calculated using both English and Dutch value sets. The study sample was divided into development and validation datasets according to patients' geographical residence. Generalized estimating equations were applied to five different sets of independent variables including overall, Trial Outcome Index (TOI), and individual subscales results. The best performing models were selected based on mean absolute error (MAE) and root-mean square error (RMSE). EQ-5D-5L and FAACT/FACIT-F results were available for 96 patients. The developed algorithms showed a good predictive performance, with acceptable MAE/RMSE and small differences between mean observed and predicted EQ-5D-5L utilities. In FACT-G models, Physical Well-Being had the highest explanatory value, while Emotional Well-Being did not significantly affect the EQ-5D-5L score; Anorexia-Cachexia and Fatigue subscales were highly statistically significant in FAACT and FACIT-F models, respectively, as well as the TOI scores. The Eastern Cooperative Oncology Group status was included as covariate in all models. The developed algorithms enable the estimation of EQ-5D-5L utilities from three cancer-specific instruments when preference-based HRQoL data are missing.

  10. A Comparison of the Validity and Responsiveness of the EQ-5D-5L and SF-6D for Measuring Health Spillovers: A Study of the Family Impact of Meningitis.

    Science.gov (United States)

    Bhadhuri, Arjun; Jowett, Sue; Jolly, Kate; Al-Janabi, Hareth

    2017-05-01

    The "health spillover" of patient illness on family members is important to capture in economic evaluation. This study compares the construct validity and responsiveness of 2 widely used health-related quality-of-life instruments, the EQ-5D-5L and SF-6D, in capturing health spillover effects for family members with and without an informal care role (carers and noncarers). Construct validity and responsiveness were assessed using data from a 2012 UK survey of the family impact of meningitis-related sequelae. Construct validity was assessed by testing associations between family members' health status and variables anticipated to be associated with spillover effects (patient health status and informal care). Responsiveness was assessed by testing associations between the longitudinal change in family members' health status and longitudinal change in patient health and caring hours. Among noncarers, both the EQ-5D-5L and the SF-6D exhibited construct validity with 10 of the 11 associations that were hypothesized being statistically significant on both measures. There was less clear evidence of responsiveness of the measures for noncarers. Among carers, the EQ-5D-5L exhibited greater construct validity, as well as responsiveness, with respect to spillovers from patient health. This was evidenced by the EQ-5D-5L detecting 9 significant associations compared with 4 on the SF-6D. However, the SF-6D exhibited greater construct validity with respect to spillovers generated from informal care provision (5 associations significant compared with 2 on the EQ-5D-5L). Both the EQ-5D-5L and the SF-6D exhibited a degree of validity that could justify their use as measures of health-related quality-of-life spillovers on family members in economic evaluation.

  11. Experimental investigation of axially loaded steel fiber reinforced high strength concrete-filled steel tube columns

    Institute of Scientific and Technical Information of China (English)

    卢亦焱; 李娜; 李杉; 梁鸿骏

    2015-01-01

    An experimental study on the compressive behavior of steel fiber reinforced concrete-filled steel tube columns is presented. Specimens were tested to investigate the effects of the concrete strength, the thickness of steel tube and the steel fiber volume fraction on the ultimate strength and the ductility. The experimental results indicate that the addition of steel fibers in concrete can significantly improve the ductility and the energy dissipation capacity of the concrete-filled steel tube columns and delay the local buckling of the steel tube, but has no obvious effect on the failure mode. It has also been found that the addition of steel fibers is a more effective method than using thicker steel tube in enhancing the ductility, and more advantageous in the case of higher strength concrete. An analytical model to estimate the load capacity is proposed for steel tube columns filled with both plain concrete and steel fiber reinforced concrete. The predicted results are in good agreement with the experimental ones obtained in this work and literatures.

  12. Evaluation of Steel Cleanliness in a Steel Deoxidized Using Al

    Science.gov (United States)

    Castro-Cedeño, Edgar-Ivan; Herrera-Trejo, Martín; Castro-Román, Manuel; Castro-Uresti, Fabián; López-Cornejo, Monserrat

    2016-06-01

    The effect of magnesium in the aluminum used as a deoxidizer on the cleanliness of steel was studied throughout a steelmaking route for the production of thin slabs. Two deoxidizers with different Mg contents were used. The Mg content of a "typical" deoxidizer was ~0.5 wt pct Mg, whereas that for an alternative deoxidizer was ~2 wt pct Mg. The inclusion population at different stages of the steelmaking process was characterized in terms of chemical composition, number, and size distribution. The inclusion modification path shows that the solid Al2O3 and Al2O3-MgO inclusions formed in the early stage of the steel ladle treatment are modified into Al2O3-MgO-CaO liquid and MgO-Al2O3-liquid inclusions. Although some slight differences were observed in the ladle furnace samples, the chemical composition of inclusions was similar in the samples taken at the mold of the continuous casting, regardless of the deoxidizer used. Gumbel, generalized extreme value (GEV), and generalized Pareto (GP) distributions were used for the description of the size distribution. The GEV and GP distributions resulted in proper distributions to describe the evolution of size distribution throughout the steelmaking process. Furthermore, no statistically significant differences between inclusion size distributions resulting from the use of either deoxidizer were found.

  13. Reconstruction of Space Steel Constructions

    OpenAIRE

    BRODNIANSKY, Jan; AGOCS, Zoltan; AROCH, Rudolf; SLIVANSKY, Milos

    2010-01-01

    p. 1328-1337 Reconstruction of some special types of constructions - silos, timber roof structure and a winter stadium are described. The silos are cylindrical with a diameter of 36.0m with a total height of 50.5m. The silo shell is made from steel plates of variable thickness. Capacity of the silo is 60 000t. Gradually, during more than 30 years of operation, local deformations and distinctive 6000mm high cracks in the bottom part of the shells of the silos developed. On the basis o...

  14. Help for the Steel Industry

    Science.gov (United States)

    1991-01-01

    A collaboration between NASA Lewis Research Center (LRC) and Gladwin Engineering resulted in the adaptation of aerospace high temperature metal technology to the continuous casting of steel. The continuous process is more efficient because it takes less time and labor. A high temperature material, once used on the X-15 research plane, was applied to metal rollers by a LRC developed spraying technique. Lewis Research Center also supplied mold prototype of metal composites, reducing erosion and promoting thermal conductivity. Rollers that previously cracked due to thermal fatigue, lasted longer. Gladwin's sales have increased, and additional NASA-developed innovations are anticipated.

  15. [Initial stages of steel biocorrosion].

    Science.gov (United States)

    Zhigletsova, S K; Rodin, V B; Kobelev, V S; Aleksandrova, N V; Rasulova, G E; Kholodenko, V P

    2000-01-01

    Initial stages of corrosion of mild steel induced by Klebsiela rhinoscleromatis BO2 were studied in various media. The effect of the microorganism was detected 8-10 h after inoculation. The number of viable cells were virtually unchanged within one month in all media, but the corrosive activity of the strain decreased. The corrosive activity of microorganisms can be determined by spectrophotometry even only after incubation for 24 h. At a low level of organic substrate, even strong colonization with microorganisms does not inevitably result in a significant damage to metals.

  16. Steel plate reinforcement of orthotropic bridge decks

    NARCIS (Netherlands)

    Teixeira de Freitas, S.

    2012-01-01

    The PhD research is focused on the reinforcement of fatigue cracked orthotropic steel bridge decks (OBD) by adding a second steel plate to the existing deck. The main idea is to stiffen the existing deck plate, which will reduce the stresses at the fatigue sensitive details and extend the fatigue li

  17. Purification of post-consumer steel crap

    NARCIS (Netherlands)

    Rem, P.C.; Van den Broeck, F.; Bakker, M.C.M.

    2012-01-01

    Post-consumer steel scrap is often hand picked for contaminants such as copper to meet specifications of steelmakers. If the hand sorting capacity exceeds 20 tons scrap/h the efficiency generally becomes problematic, leaving 50% of the copper contaminants in the steel product. In response, new techn

  18. Bauxite Based Bricks for Steel Ladle

    Institute of Scientific and Technical Information of China (English)

    Yu Lingyan; Peng Xigao

    2011-01-01

    @@ 1.Scope This standard specifies the classification,technical requirements,test methods,inspection rules,packing,marking,transportation,storage,and quality certificate of bauxite based bricks for steel ladle linings.This standard is applicable to bauxite based bricks for working layer of steel ladle.

  19. Optimising steel hub location in Thailand

    Directory of Open Access Journals (Sweden)

    Sakaradhorn Boontaveeyuwat

    2012-11-01

    Full Text Available The optimal location of a steel hub in Thailand was analysed by applying aspecific research methodology designed to evaluate locations near the seaports. The growth of Thailand’s steel industry has become a centre of attention in the last decade, resulting in substantial efforts to form a distribution service centre to minimise the logistic costs associated with handling large steel flows in the future. The main analysis of the steel hublocation focused on areas situated near Laem Cha Bang, Map Ta Phut and Prachuab ports since these top three ports are considered important in terms of their steel throughput in Thailand. The transport costs associated with the shipment and inland transport together with port tariffs were calculated for the proposed scenarios of steel hub establishment andthese were compared with the existing situation without steel hub. The findings showed that a steel hub located near Laem Cha Bang port was the optimal option involving a saving of 9.4% on the total system costs incurred under the existing situation.

  20. Low Mn alloy steel for cryogenic service

    Science.gov (United States)

    Morris, J.W. Jr.; Niikura, M.

    A ferritic cryogenic steel which has a relatively low (about 4 to 6%) manganese content and which has been made suitable for use at cryogenic temperatures by a thermal cycling treatment followed by a final tempering. The steel includes 4 to 6% manganese, 0.02 to 0.06% carbon, 0.1 to 0.4% molybdenum and 0 to 3% nickel.

  1. Nanostructuring steel for injection molding tools

    DEFF Research Database (Denmark)

    Al-Azawi, A.; Smistrup, Kristian; Kristensen, Anders

    2014-01-01

    and ion beam etching are combined to nanostructure the planar surface of a steel wafer. Injection molded plastic parts with enhanced surface properties, like anti-reflective, superhydrophobic and structural colors can be achieved by micro-and nanostructuring the surface of the steel molds. We investigate...

  2. Forming "dynamic" membranes on stainless steel

    Science.gov (United States)

    Brandon, C. A.; Gaddis, J. L.

    1979-01-01

    "Dynamic" zirconium polyacrylic membrane is formed directly on stainless steel substrate without excessive corrosion of steel. Membrane is potentially useful in removal of contaminated chemicals from solution through reversed osmosis. Application includes use in filtration and desalination equipment, and in textile industry for separation of dyes from aqueous solvents.

  3. Sprayformed Hot Work Steels for Rapid Tooling

    Institute of Scientific and Technical Information of China (English)

    Yunfeng Yang; Simo-Pekka Hannula

    2003-01-01

    The present work compares microstructures of hot work steels made by different processes, that is, by sprayforming,by casting, and a commercially supplied H13 steel. Material benefits are recognized by sprayforming hot working tools such as die inserts fo

  4. Microstructure and transformation kinetics in bainitic steels

    NARCIS (Netherlands)

    Luzginova, N.V.

    2008-01-01

    With the aim of reaching a better understanding of the microstructure evolution and the overall phase transformation kinetics in hyper-eutectoid steels a commercial SAE 52100 bearing steel and 7 model alloys with different concentrations of chromium, cobalt and aluminum have been studied in this wor

  5. Evaluation of Flash Bainite in 4130 Steel

    Science.gov (United States)

    2011-07-01

    Technical Report ARWSB-TR-11011 Evaluation of Flash Bainite in 4130 Steel G. Vigilante M. Hespos S. Bartolucci...4. TITLE AND SUBTITLE Evaluation of Flash Bainite in 4130 Steel 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...STATEMENT 13. SUPPLEMENTARY NOTES 14. ABSTRACT ARDEC independently evaluated a Flash Bainite process developed by Gary Cola, Jr., Sirius Protection

  6. Microstructure and transformation kinetics in bainitic steels

    NARCIS (Netherlands)

    Luzginova, N.V.

    2008-01-01

    With the aim of reaching a better understanding of the microstructure evolution and the overall phase transformation kinetics in hyper-eutectoid steels a commercial SAE 52100 bearing steel and 7 model alloys with different concentrations of chromium, cobalt and aluminum have been studied in this

  7. Behaviour of high strength steel moment joints

    NARCIS (Netherlands)

    Girão Coelho, A.M.; Bijlaard, F.S.K.

    2010-01-01

    The design of joints to European standard EN 1993 within the semi-continuous/partially restrained philosophy is restricted to steel grades up to S460. With the recent development of high performance steels, the need for these restrictions should be revisited. The semicontinuous joint modelling can b

  8. History dependence of magnetomechanical properties of steel

    Science.gov (United States)

    Melquiond, F.; Mouroux, A.; Jouglar, J.; Vuillermoz, P. L.; Weinstock, H.

    1996-05-01

    Magnetomechanical measurements using a superconducting SQUID magnetic gradiometer and a tensile-testing machine have been performed on a variety of steel specimens to determine the change in magnetization due to applied stress and the possible application of the observed behavior as a new form of nondestructive evaluation in steel. This study builds on earlier related measurements.

  9. Steel Sheet Pile Walls in Soft Soil

    NARCIS (Netherlands)

    Kort, D.A.

    2002-01-01

    For almost a century, steel sheet pile walls are applied worldwide as earth retaining structures for excavations and quay walls. Within the framework of the development of European structural codes for Civil Engineering works, the Eurocodes, Eurocode 3 Part 5 for design of steel sheet pile walls was

  10. Fatigue of stainless steel in hydrogen

    Science.gov (United States)

    Schuster, G.; Altstetter, C.

    1983-10-01

    The fatigue crack growth rates of two austenitic stainless steel alloys, AISI 301 and 302, were compared in air, argon, and hydrogen environments at atmospheric pressure and room temperature. Under the stresses at the crack tip the austenite in type 301 steel transformed martensitically to a’ to a greater extent than in type 302 steel. The steels were also tested in the cold worked condition under hydrogen or argon. Hydrogen was found to have a deleterious effect on both steels, but the effect was stronger in the unstable than in the stable alloy. Cold work decreased fatigue crack growth rates in argon and hydrogen, but the decrease was less marked in hydrogen than in argon. Metallographic, fractographic, and microhardness surveys in the vicinity of the fatigue crack were used to try to understand the reasons for the observed fatigue behavior.

  11. Hydrogen embrittlement in power plant steels

    Indian Academy of Sciences (India)

    R K Dayal; N Parvathavarthini

    2003-06-01

    In power plants, several major components such as steam generator tubes, boilers, steam/water pipe lines, water box of condensers and the other auxiliary components like bolts, nuts, screws fasteners and supporting assemblies are commonly fabricated from plain carbon steels, as well as low and high alloy steels. These components often fail catastrophically due to hydrogen embrittlement. A brief overview of our current understanding of the phenomenon of such hydrogen damage in steels is presented in this paper. Case histories of failures of steel components due to hydrogen embrittlement, which are reported in literature, are briefly discussed. A phenomenological assessment of overall process of hydrogen embrittlement and classification of the various damage modes are summarized. Influence of several physical and metallurgical variables on the susceptibility of steels to hydrogen embrittlement, mechanisms of hydrogen embrittlement and current approaches to combat this problem are also presented.

  12. Hydrogen transport in iron and steel

    Science.gov (United States)

    Louthan, M. R., Jr.; Derrick, R. G.; Donovan, J. A.; Caskey, G. R., Jr.

    1976-01-01

    The permeabilities of protium, deuterium, and tritium in foil specimens of Marz grade iron, 4130 steel, Armco iron, HP-9-4-20, and T-1 steels were studied at hydrogen pressures between 0.02 and 0.5 MPa over the temperature range 260-700 K. The permeability was measured by a pressure-rise method, deuterium counting with a detector, and radioactivity counting. Good agreement is found between the measurement techniques used. It is shown that the permeabilities of protium, deuterium, and tritium in iron and T-1 steel at temperatures as low as 260 K are in good agreement with the equation proposed by Gonzalez (1967). However, the permeabilities of HP-9-4-20 and 4130 steel to hydrogen are typically lower than predicted. The isotope effect on hydrogen permeability of HP-9-4-20, 4130 and T-1 steels, and high-purity iron can be estimated by an inverse square root of mass correction.

  13. Interaction between stainless steel and plutonium metal

    Energy Technology Data Exchange (ETDEWEB)

    Dunwoody, John T [Los Alamos National Laboratory; Mason, Richard E [Los Alamos National Laboratory; Freibert, Franz J [Los Alamos National Laboratory; Willson, Stephen P [Los Alamos National Laboratory; Veirs, Douglas K [Los Alamos National Laboratory; Worl, Laura A [Los Alamos National Laboratory; Archuleta, Alonso [Los Alamos National Laboratory; Conger, Donald J [Los Alamos National Laboratory

    2010-01-01

    Long-term storage of excess plutonium is of great concern in the U.S. as well as abroad. The current accepted configuration involves intimate contact between the stored material and an iron-bearing container such as stainless steel. While many safety scenario studies have been conducted and used in the acceptance of stainless steel containers, little information is available on the physical interaction at elevated temperatures between certain forms of stored material and the container itself. The bulk of the safety studies has focused on the ability of a package to keep the primary stainless steel containment below the plutonium-iron eutectic temperature of approximately 410 C. However, the interactions of plutonium metal with stainless steel have been of continuing interest. This paper reports on a scoping study investigating the interaction between stainless steel and plutonium metal in a pseudo diffusion couple at temperatures above the eutectic melt-point.

  14. Kagi steel warehouse, Winterthur, Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Guetermann, A.

    1999-07-01

    The steel warehouse of the Kagi company in Winterthur near Zurich is a two-hall complex. The older (left) hall (3,000 m{sup 2}, 30,000 m{sup 3}) was completely uninsulated and has an open basement (6,500 m{sup 3}) to store infrequently used items. To prevent condensation on the cold steel surfaces in spring and early summer and to provide a smaller temperature difference between the hall and the basement for workers in the summer, (and avoid productivity loss due to illness), as well as to raise temperatures in the winter, the following measures were taken in a step-by-step approach: A ventilation system was installed (1986) to circulate sun-warmed air from under the roof to the basement. It was shown that, under the given circumstances, such a system worked well and was cost-effective in comparison with a conventional heating system. Complete external insulation was added to the hall (1994) and a roof-integrated 350 m{sup 2} air collector installed so that the circulating air could be warmed. Construction of a separate adjoining new hall (1996) profited from all the above experience. The air collector is integrated in the facade facing south-east. The first stage (1986) was monitored in detail, while only rough measurements were made for the modified system (1994). The 1996 system for the new hall was analysed by computer simulation. (author)

  15. Automated Steel Cleanliness Analysis Tool (ASCAT)

    Energy Technology Data Exchange (ETDEWEB)

    Gary Casuccio (RJ Lee Group); Michael Potter (RJ Lee Group); Fred Schwerer (RJ Lee Group); Dr. Richard J. Fruehan (Carnegie Mellon University); Dr. Scott Story (US Steel)

    2005-12-30

    The objective of this study was to develop the Automated Steel Cleanliness Analysis Tool (ASCATTM) to permit steelmakers to evaluate the quality of the steel through the analysis of individual inclusions. By characterizing individual inclusions, determinations can be made as to the cleanliness of the steel. Understanding the complicating effects of inclusions in the steelmaking process and on the resulting properties of steel allows the steel producer to increase throughput, better control the process, reduce remelts, and improve the quality of the product. The ASCAT (Figure 1) is a steel-smart inclusion analysis tool developed around a customized next-generation computer controlled scanning electron microscopy (NG-CCSEM) hardware platform that permits acquisition of inclusion size and composition data at a rate never before possible in SEM-based instruments. With built-in customized ''intelligent'' software, the inclusion data is automatically sorted into clusters representing different inclusion types to define the characteristics of a particular heat (Figure 2). The ASCAT represents an innovative new tool for the collection of statistically meaningful data on inclusions, and provides a means of understanding the complicated effects of inclusions in the steel making process and on the resulting properties of steel. Research conducted by RJLG with AISI (American Iron and Steel Institute) and SMA (Steel Manufactures of America) members indicates that the ASCAT has application in high-grade bar, sheet, plate, tin products, pipes, SBQ, tire cord, welding rod, and specialty steels and alloys where control of inclusions, whether natural or engineered, are crucial to their specification for a given end-use. Example applications include castability of calcium treated steel; interstitial free (IF) degasser grade slag conditioning practice; tundish clogging and erosion minimization; degasser circulation and optimization; quality assessment/steel

  16. Superstrength of nanograined steel with nanoscale intermetallic precipitates transformed from shock-compressed martensitic steel

    Science.gov (United States)

    Yu, Hailiang; Yan, Ming; Lu, Cheng; Tieu, Anh Kiet; Li, Huijun; Zhu, Qiang; Godbole, Ajit; Li, Jintao; Su, Lihong; Kong, Charlie

    2016-11-01

    An increasing number of industrial applications need superstrength steels. It is known that refined grains and nanoscale precipitates can increase strength. The hardest martensitic steel reported to date is C0.8 steel, whose nanohardness can reach 11.9 GPa through incremental interstitial solid solution strengthening. Here we report a nanograined (NG) steel dispersed with nanoscale precipitates which has an extraordinarily high hardness of 19.1 GPa. The NG steel (shock-compressed Armox 500T steel) was obtained under these conditions: high strain rate of 1.2 μs-1, high temperature rise rate of 600 Kμs-1 and high pressure of 17 GPa. The mean grain size achieved was 39 nm and reinforcing precipitates were indexed in the NG steel. The strength of the NG steel is expected to be ~3950 MPa. The discovery of the NG steel offers a general pathway for designing new advanced steel materials with exceptional hardness and excellent strength.

  17. 29 CFR 1926.757 - Open web steel joists.

    Science.gov (United States)

    2010-07-01

    ... approval of the project structural engineer of record. (8) Field-bolted joists. (i) Except for steel joists... 29 Labor 8 2010-07-01 2010-07-01 false Open web steel joists. 1926.757 Section 1926.757 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Steel Erection § 1926.757 Open web steel...

  18. Fatigue strength of hybrid VHSS-Cast steel welded plates.

    NARCIS (Netherlands)

    Pijpers, R.J.M.; Kolstein, M.H.; Romeijn, A.; Bijlaard, F.S.K.

    2009-01-01

    Very high strength steels (VHSS) have been made available by the steel industry for many years. In a fatigue loaded VHSS structure absolute and relative stress variation will be higher compared to stresses in structures made of lower grade steels. Cast steel, also available up to yield strength of 1

  19. 46 CFR 154.172 - Contiguous steel hull structure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Contiguous steel hull structure. 154.172 Section 154.172... Structure § 154.172 Contiguous steel hull structure. (a) Except as allowed in paragraphs (b) and (c) of this... construction of the contiguous steel hull structure must meet the thickness and steel grade in Table 1 for...

  20. 49 CFR 178.504 - Standards for steel drums.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Standards for steel drums. 178.504 Section 178.504...-bulk Performance-Oriented Packaging Standards § 178.504 Standards for steel drums. (a) The following are identification codes for steel drums: (1) 1A1 for a non-removable head steel drum; and (2) 1A2...

  1. Fatigue strength tests of layered steel

    Directory of Open Access Journals (Sweden)

    Michal Černý

    2013-01-01

    Full Text Available The work deals with original measurement of fatigue properties of formed layered steel material – damask steel. This is a material that exhibits a fine micro-structure as well as a regular composition of many material layers with complementary properties. The article experimentally verifies high-cycle fatigue properties of layered steel and evaluates them from the point of view of fatigue tests of conventional steel materials and a parallel application of a non-destructive – acoustic emission – testing. Finally, it discusses the influence of production on fatigue strength and the possibilities of using multi-layered steel materials in technological practice. A serious result of this pilot experiment is the fact documented no only by the fractographic observation, but mainly by the AE records that the fatigue service life of this material is high if it its not stressed by tension approximating the yield point Re. However, such stress is not common in practical use of tools made of damask steel and thus under common bending stress an exceptionally long service life of tools made of this type of material is demonstrable. The fact that damask steel behaves like a homogeneous material is mainly confirmed by the records of the AE signal at lower values of stress σa. When stressed by higher amplitudes of tension σa damask responds in AE records similarly to a laminate material that is stressed by bending.

  2. Preparation of precursor for stainless steel foam

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xiang-yang; LI Shan-ni; LI Jie; LIU Ye-xiang

    2008-01-01

    The effects of polyurethane sponge pretreatment and slurry compositions on the slurry loading in precursor were discussed, and the,performances of stainless steel foams prepared from precursors with different slurry loadings and different particle sizes of the stainless steel powder were also investigated. The experimental results show that the pretreatment of sponge with alkaline solution is effective to reduce the jam of cells in precursor and ensure the slurry to uniformly distribute in sponge, and it is also an effective method for increasing the slurry loading in precursor; the mass fraction of additive A and solid content in slurry greatly affect the slurry loading in precursor, when they are kept in 9%-13% and 52%-75%, respectively, the stainless steel foam may hold excellent 3D open-cell network structure and uniform muscles; the particle size of the stainless steel powder and the slurry loading in precursor have great effects on the bending strength, apparent density and open porosity of stainless steel foam; when the stainless steel powder with particle size of 44 tan and slurry loading of 0.5 g/cm3 in precursor are used, a stainless steel foam can be obtained, which has open porosity of 81.2%, bending strength of about 51.76 MPa and apparent density of about 1.0 g/cm3.

  3. Redemption of asthma pharmaceuticals among stainless steel and mild steel welders

    DEFF Research Database (Denmark)

    Kristiansen, Pernille; Jørgensen, Kristian Tore; Hansen, Johnni

    2015-01-01

    PURPOSE: The purpose was to examine bronchial asthma according to cumulative exposure to fume particulates conferred by stainless steel and mild steel welding through a proxy of redeemed prescribed asthma pharmaceuticals. METHODS: A Danish national company-based historical cohort of 5,303 male ever...... nonsignificant increased rate of redemption of asthma medicine was observed among high-level exposed stainless steel welders in comparison with low-level exposed welders (HR 1.54, 95 % CI 0.76-3.13). This risk increase was driven by an increase risk among non-smoking stainless steel welders (HR 1.46, 95 % CI 1.......06-2.02). Mild steel welding was not associated with increased risk of use asthma pharmaceuticals. CONCLUSION: The present study indicates that long-term exposure to stainless steel welding is related to increased risk of asthma in non-smokers....

  4. Dynamic characteristics of automotive steel sheets

    Directory of Open Access Journals (Sweden)

    M. Mihaliková

    2016-10-01

    Full Text Available The aim of this experimental research was to perform an analysis of deformation characteristics on two different types of steel: IF steel, and micro-alloyed steel were used automotive industry. For that purpose changes of properties of these materials were carried out by static 10-3 · s-1 and dynamic 103 · s-1 strain rate assess its plastic properties. Vickers micro hardness test was carried out by the static and dynamic loading condition and describes different hardness distribution. The higher strain hardening of materials was obtained too that was confirmed by distribution of dislocations.

  5. EIS Response of MIC on Carbon Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Maahn, Ernst

    1998-01-01

    Abstract Microbially influenced corrosion of carbon steel under sulphate reducing (sulphide-producing) bacterial activity (SRB) results in the formation of both ferrous sulphides as well as biofilm on the metal surface. The electrochemical characteristics of the ferrous sulphide/steel interface...... as compared to the biofilm/ferrous sulphide/steel interface has been studied with EIS, DC polarisations (Tafel, LPR) and a potentiostatic step technique. The electrochemical response is related to a threshold sulphide concentration above which very characteristic changes such as indications of finite...... response from the metal surface....

  6. Biocompatibility of MIM 316L stainless steel

    Institute of Scientific and Technical Information of China (English)

    ZHU Shai-hong; WANG Guo-hui; ZHAO Yan-zhong; LI Yi-ming; ZHOU Ke-chao; HUANG Bai-yun

    2005-01-01

    To evaluate the bioeompatibility of MIM 316L stainless steel, the percentage of S-period cells were detected by flow cytometry after L929 incubated with extraction of MIM 316L stainless steel, using titanium implant materials of clinical application as the contrast. Both materials were implanted in animal and the histopathological evaluations were carried out. The statistical analyses show that there are no significant differences between two groups (P>0.05), which demonstrates that MIM 316L stainless steel has a good biocompatibility.

  7. Tribocorrosion wear of austenitic and martensitic steels

    Directory of Open Access Journals (Sweden)

    G. Rozing

    2016-07-01

    Full Text Available This paper explores the impact of tribocorrosion wear caused by an aggressive acidic media. Tests were conducted on samples made of stainless steel AISI 316L, 304L and 440C. Austenitic steels were tested in their nitrided state and martensitic in quenched and tempered and then induction hardened state. Electrochemical corrosion resistance testing and analysis of the microstructure and hardness in the cross section was carried out on samples of selected steels. To test the possibility of applying surface modification of selected materials in conditions of use, tests were conducted on samples/parts in a worm press for final pressing.

  8. The stretch zone of automotive steel sheets

    Indian Academy of Sciences (India)

    Ľ Ambriško; L Pešek

    2014-04-01

    The paper deals with an experimental determination of the stretch zone dimensions in the notch tip in thin steel sheets. The stretch zone dimensions depend on steel grade, on the rolling direction as well as on the loading rate. Stretch zones were observed and measured on three steel grades. Fracture area and stretch zones were analysed by SEM. Stable crack growth was monitored by videoextensometry techniques on CT (Compact Tension) specimens. Specimens were loaded under two loading rates by eccentric tension, whereby the deformation in the notch surrounding area was recorded using a non-contact measurement–videoextensometry technique. Linear relation between the stretch zone dimensions was determined.

  9. Quenching simulation of steel grinding balls

    Energy Technology Data Exchange (ETDEWEB)

    Zapata-Hernandez, O.; Reyes, L. A.; Camurri, C.; Carrasco, C.; Garza-Monte-de-Oca, F.; Colas, R.

    2015-07-01

    The phase transformations of high carbon steel during quenching and equalizing were modelled using commercial computer packages based on the finite element method and the kinetic transformation of steel. The model was used to predict the temperature and microstructural changes taking place within balls of two different sizes that are used for grinding mineral ores. A good correlation between the temperatures measured by inserted thermocouples and those predicted by the model was obtained after modifying the thermal conductivity of the steel within the temperature domain at which mixed phases are present. The phase transformations predicted were confirmed by metallographic analyses. (Author)

  10. Solidification Based Grain Refinement in Steels

    Science.gov (United States)

    2010-07-20

    likely to form, the author conducted a Schiel solidification analysis using Thermo-Calc. Table 2 lists the steel chemistry used based on the actual...the phases present during freezing were calculated. Table 3 Steel chemistry used fur Schiel analysis. C (wt. %) Mn (wt %) AKwt. %) Ti(wt. %) N(wt...0.4 0.6 0.8 Mole fraction of all solid phases Figure 23 Schiel solidification analysis for 0.1 % Ti containing 1030 steel. Figure 25 depicts the

  11. Intergranular strains in textured steel

    Energy Technology Data Exchange (ETDEWEB)

    Daymond, M.R. [Los Alamos Neutron Science Center (LANSCE), Los Alamos, NM (United States); Tome, C.N. [Los Alamos National Lab., NM (United States). Materials Science and Technology Div.; Bourke, M.A.M. [Los Alamos Neutron Science Center (LANSCE), Los Alamos, NM (United States); Los Alamos National Lab., NM (United States). Materials Science and Technology Div.

    2000-07-01

    Tensile specimens were machined from heat treated austenitic stainless steel plate prior to and after 70% reduction by uni-directional rolling. In addition to a specimen from the as-received plate, two specimens were cut from the rolled plate, with axes parallel and perpendicular to the rolling direction respectively. In situ measurements of the strain response of multiple hkl lattice planes to an applied uniaxial tensile load were made using neutron diffraction. The experimental results are compared with predictions from a self-consistent Hill-Hutchinson model. The measured texture in the plate was approximately 3 times random, however its effect on the hkl response was small compared to the residual strains left by rolling. The apparent elastic modulus and Poisson's ratios of the planes is affected by the residual strains, which is attributed to the effect of micro-plasticity. Interpretation of residual stress measurements is considered in light of these results. (orig.)

  12. Ultrasonic attenuation in pearlitic steel.

    Science.gov (United States)

    Du, Hualong; Turner, Joseph A

    2014-03-01

    Expressions for the attenuation coefficients of longitudinal and transverse ultrasonic waves are developed for steel with pearlitic microstructure. This type of lamellar duplex microstructure influences attenuation because of the lamellar spacing. In addition, longitudinal attenuation measurements were conducted using an unfocused transducer with 10 MHz central frequency on the cross section of a quenched railroad wheel sample. The dependence of longitudinal attenuation on the pearlite microstructure is observed from the changes of longitudinal attenuation from the quenched tread surface to deeper locations. The results show that the attenuation value is lowest and relatively constant within the quench depth, then increases linearly. The experimental results demonstrate a reasonable agreement with results from the theoretical model. Ultrasonic attenuation provides an important non-destructive method to evaluate duplex microstructure within grains which can be implemented for quality control in conjunction with other manufacturing processes.

  13. High Strength Steel Welding Research

    Science.gov (United States)

    2007-11-02

    Heat Input in Structural Steels," ISIJ International, vol. 36, no. 11, pp. 1406-1412, 1996. 116. N.P. Allen, W.P. Rees, B.E. Hopkins, and H.R. Tipler ...h’ 1c ifui c hy rgnoecc onoaýttthth u sth pobcontent :of the w•eldmnt wut houts-he prob f 4c sectintc Adusin~g: the+ height of Sstandard AWS/ANSi A4.3...hhE. L4-0 ~) 0 I3 CU ci)U CD ’ L. ) C-S E < 21 ofE co I 0 CLo x 1C . I a x .JCk 0 C o + 0+ 0 o+ 0 z or• mur ’’ s-0 U Qý 0 E- II CU -U Q 𔃾- m C U 0 a

  14. Effects of low temperature on properties of structural steels

    Institute of Scientific and Technical Information of China (English)

    Yanmin Wu; Yuanqing Wang; Yongjiu Shi; Jianjing Jiang

    2004-01-01

    The experiments were carried out to measure the mechanical properties of three grades of structural steels (Q235A, 16Mn and Q390E steel ) at low temperature. It was shown that the strength of the steels increases while the plasticity and toughness decrease as temperature drops. In the transitional area the toughness drops rapidly with temperature. Among the three structural steels,Q390E steel has the best toughness and the lowest sensitivity.

  15. Project B: Improved Liquid Steel Feed For Slab Casters

    Energy Technology Data Exchange (ETDEWEB)

    Brent S. Isaacson; Mike Slepian; Thomas Richter

    1998-10-01

    This report describes the completion of the development of an electromagnetic valve to control liquid steel flow for improved liquid steel feeding for slab casters. Achievements result from a joint research effort between Westinghouse Science and Technology Center, North American Refractories and U.S. Steel. This effort is part of the American Iron and Steel Institute's (AISI) Advanced Process Control Program, a collaboration between the U.S. Department of Energy (DOE) and fifteen North American steel makers.

  16. Microstructural characterization in dissimilar friction stir welding between 304 stainless steel and st37 steel

    Energy Technology Data Exchange (ETDEWEB)

    Jafarzadegan, M. [Department of Materials Eng., Tarbiat Modares University, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of); State Key Laboratory of Advanced Welding Production Technology, School of Materials Science and Eng., Harbin Institute of Technology, P.O. Box: 150001, Harbin (China); Feng, A.H. [State Key Laboratory of Advanced Welding Production Technology, School of Materials Science and Eng., Harbin Institute of Technology, P.O. Box: 150001, Harbin (China); Abdollah-zadeh, A., E-mail: zadeh@modares.ac.ir [Department of Materials Eng., Tarbiat Modares University, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of); Saeid, T. [Advanced Materials Research Center, Sahand University of Technology, P.O. Box: 51335-1996, Tabriz (Iran, Islamic Republic of); Shen, J. [State Key Laboratory of Advanced Welding Production Technology, School of Materials Science and Eng., Harbin Institute of Technology, P.O. Box: 150001, Harbin (China); Assadi, H. [Department of Materials Eng., Tarbiat Modares University, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of)

    2012-12-15

    In the present study, 3 mm-thick plates of 304 stainless steel and st37 steel were welded together by friction stir welding at a welding speed of 50 mm/min and tool rotational speed of 400 and 800 rpm. X-ray diffraction test was carried out to study the phases which might be formed in the welds. Metallographic examinations, and tensile and microhardness tests were used to analyze the microstructure and mechanical properties of the joint. Four different zones were found in the weld area except the base metals. In the stir zone of the 304 stainless steel, a refined grain structure with some features of dynamic recrystallization was evidenced. A thermomechanically-affected zone was characterized on the 304 steel side with features of dynamic recovery. In the other side of the stir zone, the hot deformation of the st37 steel in the austenite region produced small austenite grains and these grains transformed to fine ferrite and pearlite and some products of displacive transformations such as Widmanstatten ferrite and martensite by cooling the material after friction stir welding. The heat-affected zone in the st37 steel side showed partially and fully refined microstructures like fusion welding processes. The recrystallization in the 304 steel and the transformations in the st37 steel enhanced the hardness of the weld area and therefore, improved the tensile properties of the joint. - Highlights: Black-Right-Pointing-Pointer FSW produced sound welds between st37 low carbon steel and 304 stainless steel. Black-Right-Pointing-Pointer The SZ of the st37 steel contained some products of allotropic transformation. Black-Right-Pointing-Pointer The material in the SZ of the 304 steel showed features of dynamic recrystallization. Black-Right-Pointing-Pointer The finer microstructure in the SZ increased the hardness and tensile strength.

  17. FEM Simulation of Bending Formability for Laminate Steel/Resin/Steel Lightweight Composite Sheet

    Institute of Scientific and Technical Information of China (English)

    Guancheng Ll; Yonglin KANG

    2003-01-01

    The ANSYS simulation software was used to analyze the bending formability of laminate steel/resin/steel lightweight composite sheet. The skin steel at external side produces relative slipping-off change during the bending due to its composite structure. The internal stress strain states, materials effect tools parameters and intermediate layer resin of lightweight sheet on slipping-off change were analyzed. The spring back and shear stress state after bending have also been discussed.

  18. THE STRUCTURAL ANALYSIS OF STEEL SILOS WITH CYLINDRICAL-WALL BEARING AND PROFILE-STEEL BEARING

    OpenAIRE

    Zhengjun Tang; Daibiao Zhou; Chenwei Peng; Wenping Wu

    2015-01-01

    The silos are widely used in bulk material in many fields such as agriculture, mining, chemical, electric power storage, etc. Thin metal cylindrical silo shells are vulnerable to buckling failure caused by the compressive wall friction force. In this paper, the structural analysis of two types of steel silo with cylindrical-wall bearing and profile-steel bearing is implemented by Abaqus finite element analysis. The results indicate that under the same loading conditions, steel silos with prof...

  19. Collapse Behavior of Steel Columns as Part of Steel Frame Buildings: Experiments and Numerical Models

    OpenAIRE

    Suzuki, Yusuke; Lignos, Dimitrios

    2017-01-01

    Earthquake-induced collapse risk assessment of steel frame buildings requires the use of deterioration models that simulate instabilities that cause strength and stiffness deterioration of structural steel components. In the case of steel columns in addition to cyclic deterioration in flexural strength, such models should capture the axial load – bending interaction, the axial contraction as well as the axial strength deterioration after the formation of local buckling within the column cross...

  20. Transformation behavior of steels. ; Transformation and properties of commercial steels. Tekko no hentai kyodo. ; Jitsuyo zairyo no hentai to seishitsu

    Energy Technology Data Exchange (ETDEWEB)

    Kunitake, T. (Sumikin Techno Research, Ltd., Hyogo (Japan))

    1990-08-01

    Recently, large revolution has occurred in the manufacturing processes and composition designs of steels. By considering such tendency, Materials Research Committee of Japan Steel Association carried out a co-operative research on the transformation behavior of steels. Objected steels are mainly high tensile strength steels and tempered steels, and steels for machinery structures. The research was performed on the items, such as the transformation from processed austenite and its properties, transformation and properties of steels with accelerated heating and cooling, and transformation and properties of reheated medium carbon steels. The author discusses the comparison with the transformation from unprocessed austenite, the effects of microalloying elements of Nb, Ti, V,B, etc., the effects of pre-existing textures on the transformation from in-equilibrium state austenite, and the transformation behavior of vainite and martensite in low temperatures. The research was carried out under considering the actual processes of practical use steels. 15 refs., 24 figs., 1 tab.

  1. Numerical Analysis of Composite Steel Concrete Structural Shear Walls with Steel Encased Profiles

    Directory of Open Access Journals (Sweden)

    Daniel Dan

    2009-01-01

    Full Text Available The use of common reinforced concrete shear walls in high rise buildings is sometimes limited because of the large amount of reinforcement localized at the end of the element. A good alternative in avoiding this disadvantage is to use composite steel concrete structural shear walls with steel encased profiles. This solution used for high rise buildings, offers to designers lateral stiffness, shear capacity and high bending resisting moment of structural walls. The encasement of the steel shapes in concrete is applied also for the following purposes: flexural stiffening and strengthening of compression elements; fire protection; potentially easier repairs after moderate damage; economy with respect both to material and construction. Until now in the national and international literature poor information about nonlinear behaviour of composite steel concrete structural shear walls with steel encased profiles is available. A theoretical and experimental program related to the behaviour of steel concrete structural shear walls with steel encased profiles is developed at “Politehnica” University of Timişoara. The program refers to six different elements, which differ by the shape of the steel encased profile and also by the arrangement of steel shapes on the cross section of the element. In order to calibrate the elements for experimental study some numerical analysis were made. The paper presents the results of numerical analysis with details of stress distribution, crack distribution, structural stiffness at various loads, and load bearing capacity of the elements.

  2. The comparison of frictional resistance in titanium, self-ligating stainless steel, and stainless steel brackets using stainless steel and TMA archwires: An in vitro study.

    Science.gov (United States)

    Khalid, Syed Altaf; Kumar, Vadivel; Jayaram, Prithviraj

    2012-08-01

    The aim of the study was to compare the frictional resistance of titanium, self-ligating stainless steel, and conventional stainless steel brackets, using stainless steel and titanium molybdenum alloy (TMA) archwires. We compared the frictional resistance in 0.018 slot and 0.022 slot of the three brackets - titanium, self-ligating stainless steel, and conventional stainless steel - using stainless steel archwires and TMA archwires. An in vitro study of simulated canine retraction was undertaken to evaluate the difference in frictional resistance between titanium, self-ligating stainless steel, and stainless steel brackets, using stainless steel and TMA archwires. We compared the frictional resistance of titanium, self-ligating stainless steel, and conventional stainless steel brackets, using stainless steel and TMA archwires, with the help of Instron Universal Testing Machine. One-way analysis of variance (ANOVA), Student's "t" test, and post hoc multiple range test at level of TMA archwires showed relatively less frictional resistance compared with the other groups. The titanium bracket with TMA archwires showed relatively less frictional resistance compared with the stainless steel brackets.

  3. Evaluation of Direct Diode Laser Deposited Stainless Steel 316L on 4340 Steel Substrate for Aircraft Landing Gear Application

    Science.gov (United States)

    2010-03-01

    AFRL-RX-WP-TP-2010-4149 EVALUATION OF DIRECT DIODE LASER DEPOSITED STAINLESS STEEL 316L ON 4340 STEEL SUBSTRATE FOR AIRCRAFT LANDING GEAR...March 2010 – 01 March 2010 4. TITLE AND SUBTITLE EVALUATION OF DIRECT DIODE LASER DEPOSITED STAINLESS STEEL 316L ON 4340 STEEL SUBSTRATE FOR...Code) N/A Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39-18 Evaluation of Direct Diode Laser Deposited Stainless Steel 316L on

  4. Overview of Steel Slag Application and Utilization

    Directory of Open Access Journals (Sweden)

    Lim J.W.

    2016-01-01

    Full Text Available Significant quantities of steel slag are generated as waste material or byproduct every day from steel industries. Slag is produced from different types of furnaces with different operating conditions. Slag contains Ferrous Oxide, Calcium Oxide, Silica etc. Physical and chemical properties of slag are affected by different methods of slag solidification such as air cooled, steam, and injection of additives. Several material characterization methods, such as X-ray Diffraction (XRD, Scanned Electron Microscopy (SEM and Inductive Coupled Plasma (ICP-OES are used to determine elemental composition in the steel slag. Therefore, slags can become one of the promising materials in various applications such as in transportation industry, construction, cement production, waste water and water treatment. The various applications of steel slag indicate that it can be reused and utilized rather than being disposed to the landfill. This paper presents a review of its applications and utilization.

  5. Fire-induced collapses of steel structures

    DEFF Research Database (Denmark)

    Dondera, Alexandru; Giuliani, Luisa

    Single-story steel buildings such as car parks and industrial halls are often characterised by stiff beams and flexible columns and may experience an outward (sway) collapse during a fire, endangering people and properties outside the building. It is therefore a current interest of the research...... on the beam. By means of those tables, a simple method for the assessment and the countermeasure of unsafe collapse mode of single-story steel buildings can be derived....... to investigate the collapse behaviour of single-story steel frames and identify relevant structural characteristics that influence the collapse mode. In this paper, a parametric study on the collapse a steel beam-column assembly with beam hinged connection and fixed column support is carried out under...

  6. Stainless Steel to Titanium Bimetallic Transitions

    Energy Technology Data Exchange (ETDEWEB)

    Kaluzny, J. A. [Fermilab; Grimm, C. [Fermilab; Passarelli, D. [Fermilab

    2015-01-01

    In order to use stainless steel piping in an LCLS-II (Linac Coherent Light Source Upgrade) cryomodule, stainless steel to titanium bimetallic transitions are needed to connect the stainless steel piping to the titanium cavity helium vessel. Explosion bonded stainless steel to titanium transition pieces and bimetallic transition material samples have been tested. A sample transition tube was subjected to tests and x-ray examinations between tests. Samples of the bonded joint material were impact and tensile tested at room temperature as well as liquid helium temperature. The joint has been used successfully in horizontal tests of LCLS-II cavity helium vessels and is planned to be used in LCLS-II cryomodules. Results of material sample and transition tube tests will be presented.

  7. The World's Largest Steel Casting Poured Successfully

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The world's largest steel casting -- the upper beam (or the top head) for free forging oil hydraulic press with a 18,000-ton force capacity, was poured successfully by CITIC Heavy Machinery Co., Ltd. (CITICHM) on May 22, 2008. This head piece is 11.95 meters long, 3.8 meters wide, 4.59 meters high and about 520 tons in gross weight. Pouring is the most important and critical step during its manufacturing process. The production of this huge casting requires about 830 tons of refined molten steel from 10 smelting furnaces and pouring with six ladles into the mold cavity at one time, which made it currently the world's largest steel casting poured and the most one-time molten steel organized.

  8. Clean Cast Steel Technology, Phase IV

    Energy Technology Data Exchange (ETDEWEB)

    Charles E. Bates

    2003-02-24

    The objective of the Clean Cast Steel Technology Program was to improve casting product quality by removing or minimizing oxide defects and to allow the production of higher integrity castings for high speed machining lines. Previous research has concentrated on macro-inclusions that break, chip, or crack machine tool cutters and drills and cause immediate shutdown of the machining lines. The overall goal of the project is to reduce the amount of surface macro-inclusions and improve the machinability of steel castings. Macro-inclusions and improve the machinability of steel castings. Macro-inclusions have been identified by industrial sponsors as a major barrier to improving the quality and marketability of steel castings.

  9. 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.

  10. Advances in the heat treatment of steels

    Energy Technology Data Exchange (ETDEWEB)

    Morris, J.W. Jr.; Kim, J.I.; Syn, C.K.

    1978-06-01

    A number of important recent advances in the processing of steels have resulted from the sophisticated uses of heat treatment to tailor the microstructure of the steels so that desirable properties are established. These new heat treatments often involve the tempering or annealing of the steel to accompish a partial or complete reversion from martensite to austenite. The influence of these reversion heat treatments on the product microstructure and its properties may be systematically discussed in terms of the heat treating temperature in relation to the phase diagram. From this perspective, four characteristic heat treatments are defined: (1) normal tempering, (2) inter-critical tempering, (3) intercritical annealing, and (4) austenite reversion. The reactions occurring during each of these treatments are described and the nature and properties of typical product microstructures discussed, with specific reference to new commercial or laboratory steels having useful and exceptional properties.

  11. Hydrogen compatibility handbook for stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, G.R. Jr.

    1983-06-01

    This handbook compiles data on the effects of hydrogen on the mechanical properties of stainless steels and discusses this data within the context of current understanding of hydrogen compatibility of metals. All of the tabulated data derives from continuing studies of hydrogen effects on materials that have been conducted at the Savannah River Laboratory over the past fifteen years. Supplementary data from other sources are included in the discussion. Austenitic, ferritic, martensitic, and precipitation hardenable stainless steels have been studied. Damage caused by helium generated from decay of tritium is a distinctive effect that occurs in addition to the hydrogen isotopes protium and deuterium. The handbook defines the scope of our current knowledge of hydrogen effects in stainless steels and serves as a guide to selection of stainless steels for service in hydrogen.

  12. Bitter Operation in Global Steel Industry

    Institute of Scientific and Technical Information of China (English)

    Wang Sujuan

    2009-01-01

    @@ Shrinking international demand Global economy started to decline from the second half of 2008. Along with weak real estate market and dull automobile sales, steel industry fell into stagnant operation after six-year-straight rapid development.

  13. Ferritic-austenitic cast steel - selected problems

    Directory of Open Access Journals (Sweden)

    Z. Stradomski

    2011-07-01

    Full Text Available The author has been involved in the problems occurring in the manufacture of ferritic-austenitic cast steel castings for many years. The author’s remarks and investigation results reported in this article will enable potential manufacturers to determine their own technical capabilities and structural determinants related to the chemical composition of material, which are crucial to the good quality of a casting. Particular emphasis should be laid on the role of enhanced carbon content, the presence of copper, the precipitates of the ζ phase, and the nature of solidification structure in the tendency of duplex-type cast steel to cracking. It seems that in view of the pro-ecological activities undertaken, including flue gas desulphurization in coal-fired power plants, efforts should be made in steel foundries to introduce selected grades of ferritic-austenitic cast steel to production.

  14. Lightweight Steel Solutions for Automotive Industry

    Science.gov (United States)

    Lee, Hong Woo; Kim, Gyosung; Park, Sung Ho

    2010-06-01

    Recently, improvement in fuel efficiency and safety has become the biggest issue in worldwide automotive industry. Although the regulation of environment and safety has been tightened up more and more, the majority of vehicle bodies are still manufactured from stamped steel components. This means that the optimized steel solutions enable to demonstrate its ability to reduce body weight with high crashworthiness performance instead of expensive light weight materials such as Al, Mg and composites. To provide the innovative steel solutions for automotive industry, POSCO has developed AHSS and its application technologies, which is directly connected to EVI activities. EVI is a technical cooperation program with customer covering all stages of new car project from design to mass production. Integrated light weight solutions through new forming technologies such as TWB, hydroforming and HPF are continuously developed and provided for EVI activities. This paper will discuss the detailed status of these technologies especially light weight steel solutions based on innovative technologies.

  15. Induction surface hardening of hard coated steels

    DEFF Research Database (Denmark)

    Pantleon, Karen; Kessler, Olaf; Hoffmann, Franz

    1999-01-01

    -process is the high deposition temperature, consequently the properties of steel substrates are negatively influenced. Therefore, a subsequent heat treatment of the coated steels is necessary to restore the properties of steels ready for operation. Induction surface hardening is used as a method of heat treatment....... The effect of induction surface hardening on the properties of the coating-substrate-systems is mainly characterized using investigations of microstructure and chemical composition as well as measurements of hardness and residual stresses in dependence on the distance from the surface. Furthermore......, the scratch test is used to estimate critical loads for cohesive and adhesive failure of the coatings. Additionally, distortion measurements are carried out. The results emphasize the advantage of induction surface hardening as a method of subsequent heat treatment of CVD-coated steels....

  16. Evaluation of Iron Nickel Oxide Nanopowder as Corrosion Inhibitor: Effect of Metallic Cations on Carbon Steel in Aqueous NaCl

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhry, A. U.; Mishra, Brajendra [Colorado School of Mines, Denver (United States); Mittal, Vikas [The Petroleum Institute, Abu Dhabi (United Arab Emirates)

    2016-01-15

    The aim of this study was to evaluate the use of iron-nickel oxide (Fe{sub 2}O{sub 3}.NiO) nanopowder (FeNi) as an anti-corrosion pigment for a different application. The corrosion protection ability and the mechanism involved was determined using aqueous solution of FeNi prepared in a corrosive solution containing 3.5 wt.% NaCl. Anti-corrosion abilities of aqueous solution were determined using electrochemical impedance spectroscopy (EIS) on line pipe steel (API 5L X-80). The protection mechanism involved the adsorption of metallic cations on the steel surface forming a protective film. Analysis of EIS spectra revealed that corrosion inhibition occurred at low concentration, whereas higher concentration of aqueous solution produced induction behavior.

  17. Hot ductility of continuously cast structural steels

    Energy Technology Data Exchange (ETDEWEB)

    Pytel, S.M. [Materials Science and Technology Institute, Cracow University of Technology, Cracow (Poland)

    1995-12-31

    The objective of this investigation was to explain the hot ductility of the structural steels characterized by different amount of carbon and morphology of sulfides. Two different rolling processes were simulated under computer controlled, high temperature deformation MTS system. Results of this study show that morphology of sulfides as well as temperature and amount of deformation are responsible for level of hot ductility of the steel tested. (author). 7 refs, 5 refs, 4 tabs.

  18. Cadmium Alternatives for High-Strength Steel

    Science.gov (United States)

    2011-09-22

    191 19b. TELEPHONE NUMBER (include area code) 301 -342-8101 iii Table of Contents Note that original JTP section numbers are preceded by...specified. The focus of this JTP is on high-strength structural alloy steels used for various applications. Alloy AISI 4130 was used for adhesion and...NaCl) solution under constant amplitude loading to determine fatigue life using hourglass specimens prepared from high strength AISI 4340 steel. The

  19. Occupational rhinitis due to steel welding fumes.

    Science.gov (United States)

    Castano, Roberto; Suarthana, Eva

    2014-12-01

    Exposure to welding fumes is a recognized respiratory hazard. Occupational asthma but not occupational rhinitis has been documented in workers exposed to steel welding fumes. We report a 26-year-old male with work-related rhinitis symptoms as well as lower airways symptoms suggestive of occupational asthma and metal fume fever associated with exposure to steel welding fumes. The diagnosis of occupational rhinitis was confirmed by specific inhalation challenge.

  20. Impact behaviour of stiffened steel plates

    OpenAIRE

    Sølvernes, Sindre Hellem

    2015-01-01

    The impact behavior of stiffened steel plates subjected to impact loading from concentrated loads was studied experimentally and numerically. Both dynamic and quasi-static tests of stiffened steel plates with geometry adopted from a typical external deck area on an offshore platform were conducted. The quasi-static tests were performed to study the relationship between dynamic impact behavior and the corresponding static ones. All tests were carried out in scale 1:4. To allow the executio...

  1. Toughening Mechanisms in Ultrahigh-Strength Steels

    Science.gov (United States)

    1993-12-01

    Supersaturations," Innovations in Ultrahiyh-Strength Steel Technology (34th Sagamore Armv Materials Research Conference Pro - ceedings!. G.B. Olson, et...l0Ni-8Co- lMo-Cr Steels." Hap.H.ofEM. Vol. 22. 1973. pp. 99-101. 89. F.K. Naumann, et al., "Die Änderung des Mikro - gefüges von warmfesten Stählen

  2. Industrial steel hall with bridge grane

    OpenAIRE

    Jurejevčič, Nejc

    2016-01-01

    In introduction this diploma thesis describes all main characteristics of (single block)? industrial steel hall with bridge crane. Load arrangement on the supporting structure which covers general actions (snow load and wind action), self-weight and dynamic load of bridge crane was designed with moment resisting frame in transverse direction and frame with concentric diagonal bracing in longitudinual direction. Actions induced by crane bridge was considered in design of runway beam. Steel hal...

  3. Hydrogen degradation of high strength weldable steels

    OpenAIRE

    J. Ćwiek

    2007-01-01

    Purpose: Purpose of this paper is presentation of hydrogen degradation issue of high strength steels andespecially their welded joints. Establishing of applicable mechanisms of hydrogen-enhanced cracking was theaim of performed research.Design/methodology/approach: High strength quenched and tempered steels grade S690Q were used. Weldedjoints were prepared with typical technology used in shipyards. Susceptibility to hydrogen degradation in seawater under cathodic polarization was evaluated wi...

  4. Characteristics of vacuum sintered stainless steels

    Directory of Open Access Journals (Sweden)

    Z. Brytan

    2009-04-01

    Full Text Available Purpose: In the present study duplex stainless steels were sintered in vacuum. using rapid cooling form the mixture of prealloyed and alloying element powders The purpose of this paper was to describe the obtained microstructures after sintering as well as the main mechanical properties of sintered stainless steels.Design/methodology/approach: In presented work duplex stainless steels were obtained through powder metallurgy starting from austenitic 316L or ferritic 410L prealloyed stainless steels powders by controlled addition of alloying elements powder. Prepared mixes were sintered in a vacuum furnace in 1250°C for 1h. After sintering rapid cooling (6°C/s using nitrogen under pressure was applied. Sintered compositions were subjected to structural examinations by scanning and optical microscopy and EDS analysis as well as X-ray analysis. Mechanical properties were studied through tensile tests and Charpy impact test.Findings: It was demonstrated that austenitic-ferritic microstructures with regular arrangement of both phases and absence of precipitates can be obtained with properly designed powder mix composition as well as sintering cycle with rapid cooling rate. Obtained sintered duplex stainless steels shows good mechanical properties which depends on phases ratio in the microstructure and elements partitioning (Cr/Ni between phases.Research limitations/implications: Basing on alloys characteristics applied cooling rate and powder mix composition seems to be a good compromise to obtain balanced sintered duplex stainless steel microstructures.Practical implications: Mechanical properties of obtained sintered duplex stainless steels structures are rather promising, especially with the aim of extending their field of possible applications.Originality/value: The utilization of vacuum sintering process with rapid cooling after sintering combined with use of elemental powders added to a stainless steel base powder shows its advantages in terms

  5. Analysis of plasma-nitrided steels

    Science.gov (United States)

    Salik, J.; Ferrante, J.; Honecy, F.; Hoffman, R., Jr.

    1986-01-01

    The analysis of plasma nitrided steels can be divided to two main categories - structural and chemical. Structural analysis can provide information not only on the hardening mechanisms but also on the fundamental processes involved. Chemical analysis can be used to study the kinetics for the nitriding process and its mechanisms. In this paper preliminary results obtained by several techniques of both categories are presented and the applicability of those techniques to the analysis of plasma-nitrided steels is discussed.

  6. Laser welding of advanced high strength steels

    OpenAIRE

    Ahmed, Essam Ahmed Ali

    2011-01-01

    This research work focuses on characterization of CO2 laser beam welding (LBW) of dual phase (DP) and transformation induced plasticity (TRIP) steel sheets based on experimental, numerical simulation and statistical modeling approaches. The experimental work aimed to investigate the welding induced-microstructures, hardness, tensile properties and formability limit of laser welding butt joints of DP/DP, TRIP/TRIP and DP/TRIP steel sheets under different welding speeds. The effects of shieldin...

  7. Diffraction Measurements on CPF Steel Fatigue Samples

    Science.gov (United States)

    1995-05-30

    I I I I I I I I I I I I I I I I I I I - 535 - Diffraction Measurements on CPF Steel Fatigue Samples by Percy Clark*, Tom...to the formation of a detectable fatigue crack, a series of hourglass shaped specimens were fabricated from 350WT steel , cyclically loaded to...were made between these experiments and earlier less successful similar experiments conducted on HY80 samples. The limitations and potential for the

  8. Laser Rewelding of 304L Stainless Steel.

    Energy Technology Data Exchange (ETDEWEB)

    Maguire, Michael Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rodelas, Jeffrey [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2016-11-01

    Laser welding of 304L stainless steel during component fabrication has been found to alter the chemical composition of the steel due to material evaporation. During repair or rework, or during potential reuse/ rewelding of certain components, the potential exists to alter the composition to the extent that the material becomes prone to solidification cracking. This work aims to characterize the extent of this susceptibility in order to make informed decisions regarding rewelding practice and base metal chemistry allowances.

  9. Development of Steel Foam Materials and Structures

    Energy Technology Data Exchange (ETDEWEB)

    Kenneth Kremer; Anthony Liszkiewicz; James Adkins

    2004-10-20

    In the past few years there has been a growing interest in lightweight metal foams. Demands for weight reduction, improved fuel efficiency, and increased passenger safety in automobiles now has manufacturers seriously considering the use of metal foams, in contrast to a few years ago, when the same materials would have been ruled out for technical or economical reasons. The objective of this program was to advance the development and use of steel foam materials, by demonstrating the advantages of these novel lightweight materials in selected generic applications. Progress was made in defining materials and process parameters; characterization of physical and mechanical properties; and fabrication and testing of generic steel foam-filled shapes with compositions from 2.5 wt.% to 0.7 wt.% carbon. A means of producing steel foam shapes with uniform long range porosity levels of 50 to 60 percent was demonstrated and verified with NDE methods. Steel foam integrated beams, cylinders and plates were mechanically tested and demonstrated advantages in bend stiffness, bend resistance, and crush energy absorption. Methods of joining by welding, adhesive bonding, and mechanical fastening were investigated. It is important to keep in mind that steel foam is a conventional material in an unconventional form. A substantial amount of physical and mechanical properties are presented throughout the report and in a properties database at the end of the report to support designer's in applying steel foam in unconventional ways.

  10. Ultrahigh Ductility, High-Carbon Martensitic Steel

    Science.gov (United States)

    Qin, Shengwei; Liu, Yu; Hao, Qingguo; Zuo, Xunwei; Rong, Yonghua; Chen, Nailu

    2016-10-01

    Based on the proposed design idea of the anti-transformation-induced plasticity effect, both the additions of the Nb element and pretreatment of the normalization process as a novel quenching-partitioning-tempering (Q-P-T) were designed for Fe-0.63C-1.52Mn-1.49Si-0.62Cr-0.036Nb hot-rolled steel. This high-carbon Q-P-T martensitic steel exhibits a tensile strength of 1890 MPa and elongation of 29 pct accompanied by the excellent product of tensile and elongation of 55 GPa pct. The origin of ultrahigh ductility for high-carbon Q-P-T martensitic steel is revealed from two aspects: one is the softening of martensitic matrix due to both the depletion of carbon in the matensitic matrix during the Q-P-T process by partitioning of carbon from supersaturated martensite to retained austenite and the reduction of the dislocation density in a martensitic matrix by dislocation absorption by retained austenite effect during deformation, which significantly enhances the deformation ability of martensitic matrix; another is the high mechanical stability of considerable carbon-enriched retained austenite, which effectively reduces the formation of brittle twin-type martensite. This work verifies the correctness of the design idea of the anti-TRIP effect and makes the third-generation advanced high-strength steels extend to the field of high-carbon steels from low- and medium-carbon steels.

  11. Microstructural studies of advanced austenitic steels

    Energy Technology Data Exchange (ETDEWEB)

    Todd, J. A.; Ren, Jyh-Ching [University of Southern California, Los Angeles, CA (USA). Dept. of Materials Science

    1989-11-15

    This report presents the first complete microstructural and analytical electron microscopy study of Alloy AX5, one of a series of advanced austenitic steels developed by Maziasz and co-workers at Oak Ridge National Laboratory, for their potential application as reheater and superheater materials in power plants that will reach the end of their design lives in the 1990's. The advanced steels are modified with carbide forming elements such as titanium, niobium and vanadium. When combined with optimized thermo-mechanical treatments, the advanced steels exhibit significantly improved creep rupture properties compared to commercially available 316 stainless steels, 17--14 Cu--Mo and 800 H steels. The importance of microstructure in controlling these improvements has been demonstrated for selected alloys, using stress relaxation testing as an accelerated test method. The microstructural features responsible for the improved creep strengths have been identified by studying the thermal aging kinetics of one of the 16Ni--14Cr advanced steels, Alloy AX5, in both the solution annealed and the solution annealed plus cold worked conditions. Time-temperature-precipitation diagrams have been developed for the temperature range 600 C to 900 C and for times from 1 h to 3000 h. 226 refs., 88 figs., 10 tabs.

  12. Utilization of structural steel in buildings

    Science.gov (United States)

    Moynihan, Muiris C.; Allwood, Julian M.

    2014-01-01

    Over one-quarter of steel produced annually is used in the construction of buildings. Making this steel causes carbon dioxide emissions, which climate change experts recommend be reduced by half in the next 37 years. One option to achieve this is to design and build more efficiently, still delivering the same service from buildings but using less steel to do so. To estimate how much steel could be saved from this option, 23 steel-framed building designs are studied, sourced from leading UK engineering firms. The utilization of each beam is found and buildings are analysed to find patterns. The results for over 10 000 beams show that average utilization is below 50% of their capacity. The primary reason for this low value is ‘rationalization’—providing extra material to reduce labour costs. By designing for minimum material rather than minimum cost, steel use in buildings could be drastically reduced, leading to an equivalent reduction in ‘embodied’ carbon emissions. PMID:25104911

  13. Steel desulphurization with synthetic slag

    Directory of Open Access Journals (Sweden)

    Heput, T.

    2007-02-01

    Full Text Available Generally speaking, sulphur is considered a harmful element for steel quality, reason why all the technological steps are being taken in order to eliminate it from the metal bath. This paper deals with the influence of the chemical composition, on the slag quantity and of the bath stirring condition upon the desulphurization process in the casting ladle by treatment with synthetic slag. The experiments were made at an open-hearth plant with the steel tapping in two ladles (the desulphurization was made with synthetic slag at one ladle while the other one was considered standard and at the electric steel plant and for the synthetic slag formation a mix was used, made, according to several receipts, of: lime (50-75%, fluorine (0-17%, bauxite (0-32% and aluminous slag (8-22%. The data were processed in the calculation programs EXCEL and MATLAB, which resulted in a series of correlations between the desulphurization degree and the chemical composition of the slag, respectively the slag quantity both for the charges bubbled with Argon and the unbubbled ones.

    En general, el azufre es considerado un elemento nocivo para la calidad del acero y, por eso, en la práctica, se toman todas las medidas de orden tecnológico para su eliminación del baño metálico. En este trabajo se analiza la influencia de la composición química, de la cantidad de escoria y del estado de agitación del baño sobre el proceso de desulfuración en la cuchara para fundir por tratamiento con escoria sintética. Los experimentos se han realizado en una acería evacuando el acero en dos ollas (en una cuchara se efectuó la desulfuración con escoria sintética y a la otra se consideró como patrón y en un acería eléctrica y para la formación de la escoria sintética se utilizó una mezcla producida según muchas recetas, formada por: cal (50-75%, fluorina (0-17%, bauxita (0-32% y escoria aluminosa (8-22%. Los datos han sido procesados en los programas de c

  14. Development and formability analysis of TRIP seamless steel tube

    Institute of Scientific and Technical Information of China (English)

    Zhang Zicheng; Zhu Fuxian

    2014-01-01

    In this paper, the production technology of transformation induced plasticity (TRIP) steel was first introduced into the steel tube manufacture field to produce the steel tubes with high strength and plasticity. The TRIP seamless steel tubes with the microstructure of ferrite, bainite, retained austenite and a little martensite were successfully fabricated using a cold-drawn steel tube with two-stage heat treatment technique and continu- ous heat treatment process, respectively. The ring tensile test and cold bend test were carried out to study the formability of the newly developed TRIP seamless steel tube. The results showed that the TRIP seamless steel tubes have a good cold formability, and they are available to be used in the tube hydroforming process. In ad- dition, the equipment of continuous heat treatment developed in the current study can be used to produce TRIP steel tube, and it may serve as an important reference for the industrial production of TRIP steel tube.

  15. Surface topography evolvement of galvanized steels in sheet metal forming

    Institute of Scientific and Technical Information of China (English)

    HOU Ying-ke; YU Zhong-qi; ZHANG Wei-gang; JIANG Hao-min; LIN Zhong-qin

    2009-01-01

    U-channel forming tests were performed to investigate the surface topography evolvement of hot-dip galvanized(GI) and galvannealed(GA) steels and the effects of die hardness on sheet metal forming(SMF). Experimental results indicate that the surface roughness values of the two galvanized steels increase with the number of forming, i.e., the surface topographies of galvanized steels are roughened in SMF. Moreover, GI steel has a better ability of damage-resistance than GA steel. The mechanisms of topography evolvement are different in the forming of GI and GA steels. Scratch is the main form of surface damage in the forming of GI steels. The severity of scratch can be decreased by increasing die hardness. GA steel results in exfoliating of the coating firstly and then severe scratching. The surface topography of galvannealed steels can be improved by increasing die hardness. However, the hardness should not be too high.

  16. IMPACT STRENGTH AND FAILURE ANALYSIS OF WELDED DAMASCUS STEEL

    Directory of Open Access Journals (Sweden)

    Rastislav Mintách

    2012-01-01

    Full Text Available The aim of this work was the experimental research of damascus steel from point of view of the structural analyze, impact strength and failure analyzes. The damascus steel was produced by method of forged welding from STN 41 4260 spring steel and STN 41 9312 tool steel. The damascus steel consisted of both 84 and 168 layers. The impact strength was experimentally determined for original steels and damascus steels after heat treatment in dependence on temperature in the range from -60 to 160 °C. It has been found that the impact strength of experimental steels decreased with decreasing temperature behind with correlated change of damage mode. In the case of experimental tests performed at high temperature ductile fracture was revealed and with decreasing temperature proportion of cleavage facets increased. Only the STN 41 9312 steel did not show considerable difference in values of the impact strength with changing temperature.

  17. Effect of cathodic protection on the state of steel reinforcement

    Energy Technology Data Exchange (ETDEWEB)

    Cam, Phan Luong; Thuy, Thi Bich [Hanoi University of Technology, Hanoi (Viet Nam)

    2002-10-15

    Damage of reinforced concrete structures is mainly caused by chloride or carbonation induced corrosion of steel. Cathodic protection is a very effective measure for corrosion control of steel in concrete, especially in chloride contaminated concrete. In this paper, effect of cathodic protection on the state of steel reinforcement is presented. Cathodic polarization of reinforcements in concrete was done under different submerged conditions. Cyclic potentiodynamic tests were used to determine the effect of cathodic protection on the behavior of the steel. Pitting appeared on the non-protected steel, but was not observed on the cathodically protected steel. microscopic photographs show that a close film exists on the protected steel, while the non-protected steel's film is loose. Investigated results have proved the effect of cathodic protection in restoring or strengthening passive film on the steel reinforcement

  18. 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.

  19. API SPEC 5L会标认证审核企业需做的主要准备工作%The Main Preparatory Work for Enterprise API SPEC 5L Monogram Certification

    Institute of Scientific and Technical Information of China (English)

    方晓东

    2009-01-01

    随着TSG Z0004标准实施和API SPEC 5L以及API SPEC Q1标准的换版,当前申请API SPEC 5L会标使用许可证的企业应及时做好各项准备工作,接受审核组的审核.审核前需做的准备工作主要包括:①及时与审核员充分沟通;②各种审核文件的整理和完善;③维护和保养生产现场设备,完善各岗位现场作业指导文件,确保现场各种记录完整清楚.%Along TSG Z0004 standard implement and renewal edition of API SPEC 5L and API SPEC Q1,enterprises should make all preparations for applying API SPEC 5L monogram use permit right to receive auditor check.The main preparatory work include:①to completely communicate with auditor in time;②to file and improve all kinds of documents which will be checked;③to maintain equipments in production site,improve each job-site guidance document,and insure all kinds of records integrity and clarity. Key words:certification audit;API SPEC 5L;API SPEC Q1;monogram use permit

  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. Creep strength and ductility of 9 to 12% chromium steels

    DEFF Research Database (Denmark)

    Hald, John

    2004-01-01

    Steels", which covers creep data development and analysis for parent materials and welds of all ferritic creep resistant steels ranging from low alloy steels up to 12%Cr steels. The opinions stated in the paper represent the views of the author rather than the whole ECCC WG3A group.......The present paper focuses in on long-term creep properties of parent material of the new 9-12%Cr creep resistant steels, P91, E911 and P92 developed for use in advanced ultrasupercritical power plants. These steels have been at the center of activities in the ECCC Working Group 3A (WG3A) "Ferritic...

  2. Creep strength and ductility of 9 to 12% chromium steels

    DEFF Research Database (Denmark)

    Hald, John

    2004-01-01

    The present paper focuses in on long-term creep properties of parent material of the new 9-12%Cr creep resistant steels, P91, E911 and P92 developed for use in advanced ultrasupercritical power plants. These steels have been at the center of activities in the ECCC Working Group 3A (WG3A) "Ferritic...... Steels", which covers creep data development and analysis for parent materials and welds of all ferritic creep resistant steels ranging from low alloy steels up to 12%Cr steels. The opinions stated in the paper represent the views of the author rather than the whole ECCC WG3A group....

  3. Risk of lung cancer according to mild steel and stainless steel welding

    DEFF Research Database (Denmark)

    Sørensen, Anita Rath; Thulstrup, Ane Marie; Hansen, Johnni

    2007-01-01

    to welding fume particulates. METHODS: Male metal workers employed at least 1 year at one or more Danish stainless or mild steel industrial companies from 1964 through 1984 were enrolled in a cohort. Data on occupational and smoking history were obtained by questionnaire in 1986. Welders in the cohort who.......06-1.70)]. Among the stainless steel welders, the risk increased significantly with increasing accumulative welding particulate exposure, while no exposure-response relation was found for mild steel welders, even after adjustment for tobacco smoking and asbestos exposure. CONCLUSIONS: The study corroborates...... earlier findings that welders have an increased risk of lung cancer. While exposure-response relations indicate carcinogenic effects related to stainless steel welding, it is still unresolved whether the mild steel welding process carries a carcinogenic risk....

  4. W–steel and W–WC–steel composites and FGMs produced by hot pressing

    Energy Technology Data Exchange (ETDEWEB)

    Matějíček, Jiří, E-mail: jmatejic@ipp.cas.cz [Institute of Plasma Physics, Za Slovankou 3, 18200 Praha (Czech Republic); Boldyryeva, Hanna; Brožek, Vlastimil [Institute of Plasma Physics, Za Slovankou 3, 18200 Praha (Czech Republic); Sachr, Pavel [Innovation Centre for Diagnostics and Application of Materials, Czech Technical University, Karlovo nám. 13, 12135 Praha (Czech Republic); Chráska, Tomáš [Institute of Plasma Physics, Za Slovankou 3, 18200 Praha (Czech Republic); Pala, Zdenek [Institute of Plasma Physics, Za Slovankou 3, 18200 Praha (Czech Republic); Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, Břehová 7, 11519 Praha (Czech Republic)

    2015-11-15

    Highlights: • Tungsten–steel and tungsten–WC–steel composites and FGMs were prepared by hot pressing. • Fully dense products were obtained. • Structure, thermal and mechanical properties were characterized. • Intermetallic phase formation was observed. - Abstract: Tungsten–steel composites and functionally graded materials (FGMs) are being developed for potential application in plasma facing components of fusion devices. Their role is to reduce thermal stresses at the interface between plasma facing tungsten armor and structural material. In this study, uniform composites and graded layers produced from tungsten and steel powders by hot pressing were investigated. Fully dense composites with uniform distribution and good bonding of the phases were formed. A thin layer of Fe{sub 2}W intermetallic phase was found at the interfaces. To avoid its formation, a third phase (tungsten carbide) was introduced between tungsten and steel. Structure, thermal and mechanical properties of both types of composites in the as-produced and annealed state were characterized.

  5. Analysis of the Behaviour of Composite Steel and Steel Fiber Reinforced Concrete Slabs

    Directory of Open Access Journals (Sweden)

    Mindaugas Petkevičius

    2011-04-01

    Full Text Available There was a pending influence of steel fiber on the strength and stiffness of composite steel–concrete slabs under statical short–time load. Steel profiled sheeting and steel fiber reinforced concrete were used for specimens. Four composite slabs were made. Experimental investigations into the behaviour and influence of steel fiber reinforced concrete in composite slabs were conducted. Transverse, longitudinal, shear deformation and deflection of the slab were measured. The results indicated that the use of steel fiber in composite slabs was effective: strength was 20–24 % higher and the meanings of deflections under the action of the bending moment were 0,6MR (where MR is the bending moment at failure of the slabs and were 16–18 % lower for slabs with usual concrete. Article in Lithuanian

  6. High Mn austenitic stainless steel

    Science.gov (United States)

    Yamamoto, Yukinori [Oak Ridge, TN; Santella, Michael L [Knoxville, TN; Brady, Michael P [Oak Ridge, TN; Maziasz, Philip J [Oak Ridge, TN; Liu, Chain-tsuan [Knoxville, TN

    2010-07-13

    An austenitic stainless steel alloy includes, in weight percent: >4 to 15 Mn; 8 to 15 Ni; 14 to 16 Cr; 2.4 to 3 Al; 0.4 to 1 total of at least one of Nb and Ta; 0.05 to 0.2 C; 0.01 to 0.02 B; no more than 0.3 of combined Ti+V; up to 3 Mo; up to 3 Co; up to 1W; up to 3 Cu; up to 1 Si; up to 0.05 P; up to 1 total of at least one of Y, La, Ce, Hf, and Zr; less than 0.05 N; and base Fe, wherein the weight percent Fe is greater than the weight percent Ni, and wherein the alloy forms an external continuous scale including alumina, nanometer scale sized particles distributed throughout the microstructure, the particles including at least one of NbC and TaC, and a stable essentially single phase FCC austenitic matrix microstructure that is essentially delta-ferrite-free and essentially BCC-phase-free.

  7. Mechanical properties of irradiated 9Cr-2WVTa steel

    Energy Technology Data Exchange (ETDEWEB)

    Klueh, R.L.; Alexander, D.J. [Oak Ridge National Lab., TN (United States); Rieth, M. [Forschungszentrum Karlsruhe (Germany). Inst. fuer Materialforschung II

    1998-09-01

    An Fe-9Cr-2W-0.25V-0.07Ta-0.1C (9Cr-2WVTa) steel has excellent strength and impact toughness before and after irradiation in the Fast Flux Test Facility and the High Flux Reactor (HFR). The ductile-brittle transition temperature (DBTT) increased only 32 C after 28 dpa at 365 C in FFTF, compared to a shift of {approx}60 C for a 9Cr-2WV steel--the same as the 9Cr-2WVTa steel but without tantalum. This difference occurred despite the two steels having similar tensile but without tantalum. This difference occurred despite the two steels having similar tensile properties before and after irradiation. The 9Cr-2WVTa steel has a smaller prior-austenite grain size, but otherwise microstructures are similar before irradiation and show similar changes during irradiation. The irradiation behavior of the 9Cr-2WVTa steel differs from the 9Cr-2WV steel and other similar steels in two ways: (1) the shift in DBTT of the 9Cr-2WVTa steel irradiated in FFTF does not saturate with fluence by {approx}28 dpa, whereas for the 9Cr-2WV steel and most similar steels, saturation occurs at <10 dpa, and (2) the shift in DBTT for 9Cr-2WVTa steel irradiated in FFTF and HFR increased with irradiation temperature, whereas it decreased for the 9Cr-2WV steel, as it does for most similar steels. The improved properties of the 9Cr-2WVTa steel and the differences with other steels were attributed to tantalum in solution.

  8. In situ 3D monitoring of corrosion on carbon steel and ferritic stainless steel embedded in cement paste

    KAUST Repository

    Itty, Pierre-Adrien

    2014-06-01

    In a X-ray microcomputed tomography study, active corrosion was induced by galvanostatically corroding steel embedded in cement paste. The results give insight into corrosion product build up, crack formation, leaching of products into the cracks and voids, and differences in morphology of corrosion attack in the case of carbon steel or stainless steel reinforcement. Carbon steel was homogeneously etched away with a homogeneous layer of corrosion products forming at the steel/cement paste interface. For ferritic stainless steel, pits were forming, concentrating the corrosion products locally, which led to more extensive damage on the cement paste cover. © 2014 Elsevier Ltd.

  9. Hydrogen trapping in high-strength steels

    Energy Technology Data Exchange (ETDEWEB)

    Pound, B.G. [SRI International, Menlo Park, CA (United States). Materials Research Center

    1998-10-09

    Hydrogen trapping in three high-strength steels -- AerMet 100 and AISI 4340 and H11 -- was studied using a potentiostatic pulse technique. Irreversible trapping constants (k) and hydrogen entry fluxes were determined for these alloys in 1 mol/1 acetic acid/1 mol/1 sodium acetate. The order of the k values for the three steels and two 18Ni maraging steels previously studies inversely parallels their threshold stress intensities for stress corrosion cracking (K{sub 1SCC}). Irreversible trapping in AerMet 100 varies with aging temperature and appears to depend on the type of carbide (Fe{sub 3}C or M{sub 2}C) present. For 4340 steel, k can be correlated with K{sub 1SCC} over a range of yield strengths. The change in k is consistent with a change in the principal type of irreversible trap from matrix boundaries to incoherent Fe{sub 3}C. The principal irreversible traps in H11 at high yield strengths are thought to be similar to those in 4340 steel.

  10. Process development of thin strip steel casting

    Energy Technology Data Exchange (ETDEWEB)

    Sussman, R.C.; Williams, R.S.

    1990-12-01

    An important new frontier is being opened in steel processing with the emergence of thin strip casting. Casting steel directly to thin strip has enormous benefits in energy savings by potentially eliminating the need for hot reduction in a hot strip mill. This has been the driving force for numerous current research efforts into the direct strip casting of steel. The US Department of Energy initiated a program to evaluate the development of thin strip casting in the steel industry. In earlier phases of this program, planar flow casting on an experimental caster was studied by a team of engineers from Westinghouse Electric corporation and Armco Inc. A subsequent research program was designed as a fundamental and developmental study of both planar and melt overflow casting processes. This study was arranged as several separate and distinct tasks which were often completed by different teams of researchers. An early task was to design and build a water model to study fluid flow through different designs of planar flow casting nozzles. Another important task was mathematically modeling of melt overflow casting process. A mathematical solidification model for the formation of the strip in the melt overflow process was written. A study of the material and conditioning of casting substrates was made on the small wheel caster using the melt overflow casting process. This report discusses work on the development of thin steel casting.

  11. The Synchrotron Radiation for Steel Research

    Directory of Open Access Journals (Sweden)

    Piyada Suwanpinij

    2016-01-01

    Full Text Available The synchrotron X-ray radiation is a great tool in materials characterization with several advantageous features. The high intensity allows clear interaction signals and high energy of X-ray yields higher sampling volume. The samples do not need extra preparation and the microstructure is therefore not affected. With the tunability of the X-ray energy, a large range of elements and features in the samples can be investigated by different techniques, which is a significant difference between a stand-alone X-ray tube and synchrotron X-ray. Moreover, any experimental equipment can be installed through which the synchrotron beam travels. This facilitates the so-called in situ characterization such as during heat treatment, hot deformation, chemical reaction or welding. Although steel which possesses rather high density requires very high energy X-ray for large interaction volume, lower energy is still effective for the investigation of local structure of nanoconstituents. This work picks up a couple examples employing synchrotron X-ray for the characterization of high strength steels. The first case is the quantification of precipitates in high strength low alloyed (HSLA steel by X-ray absorption spectroscopy. The other case is the in situ X-ray diffraction for phase fraction and carbon partitioning in multiphase steels such as transformation induced plasticity (TRIP steel.

  12. Bearing and gear steels for aerospace applications

    Science.gov (United States)

    Zaretsky, Erwin V.

    1990-01-01

    Research in metallurgy and processing for bearing and gear steels has resulted in improvements in rolling-element bearing and gear life for aerospace application by a factor of approximately 200 over that obtained in the early 1940's. The selection and specification of a bearing or gear steel is dependent on the integration of multiple metallurgical and physical variables. For most aerospace bearings, through-hardened VIM-VAR AISI M-50 steel is the material of preference. For gears, the preferential material is case-carburized VAR AISI 9310. However, the VAR processing for this material is being replaced by VIM-VAR processing. Since case-carburized VIM-VAR M-50NiL incorporates the desirable qualities of both the AISI M-50 and AISI 9310 materials, optimal life and reliability can be achieved in both bearings and gears with a single steel. Hence, this material offers the promise of a common steel for both bearings and gears for future aerospace applications.

  13. Thermodynamic aspects of inclusion engineering in steels

    Institute of Scientific and Technical Information of China (English)

    A. Costa e Silva

    2006-01-01

    Tailoring non-metallic inclusions in accordance to the desired effect on steel properties has gained widespread acceptance in the last decades and has become known as "inclusion engineering". Effective inclusion engineering involves three steps: (a) a good knowledge of how inclusions influence properties, (b) understanding what is the effect of each type of inclusions on these properties and thus which is the most desirable inclusion in a given product and (c) adjusting the processing parameters to obtain these inclusions. A significant portion of the process adjustment is done during steel refining, where the steel can be tailored so that the desired chemical composition of the non-metallic inclusions that will precipitate can be altered. Understanding the relations between steel chemistry, processing variables and inclusion chemical composition requires significant understanding of the thermodynamics of the systems involved. These complex equilibrium calculations are best done using computational thermodynamics. In this work some of the basic techniques used to control inclusion composition are reviewed and the thermodynamic information required to perform this task is presented. Several examples of the application of computational thermodynamics to inclusion engineering of different steels grades are presented and compared with experimental results, whenever possible. The potential and limitations of the method are highlighted, in special those related to thermodynamic data and databases.

  14. Iron and steel industry process model

    Energy Technology Data Exchange (ETDEWEB)

    Sparrow, F.T.

    1978-07-01

    The model depicts expected energy-consumption characteristics of the iron and steel industry and ancillary industries for the next 25 years by means of a process model of the major steps in steelmaking from ore mining and scrap recycling to the final finishing of carbon, alloy, and stainless steel into steel products such as structural steel, slabs, plates, tubes, and bars. Two plant types are modelled: fully integrated mills and minimills. User-determined inputs into the model are: (a) projected energy materials prices for the horizon; (b) projected costs of capacity expansion and replacement; (c) energy conserving options - both operating modes and investments; (d) internal rate of return required on projects; and (e) growth in finished steel demand. Nominal input choices in the model are: DOE baseline projections for oil, gas, distillates, residuals, and electricity for energy, and 1975 actual prices for materials; actual 1975 costs; adding new technologies; 15% after taxes; and 1975 actual demand with 1.5% growth/year. Output of the model includes: energy use by type, by process, and by time period, both in total and intensity (Btu/ton); energy-conservation options chosen; and utilization rates for existing capacity, and the capacity expansion decisions of the model.

  15. Multi-objective optimization of steel nitriding

    Directory of Open Access Journals (Sweden)

    P. Cavaliere

    2016-03-01

    Full Text Available Steel nitriding is a thermo-chemical process largely employed in the machine components production to solve mainly wear and fatigue damage in materials. The process is strongly influenced by many different variables such as steel composition, nitrogen potential (range 0.8–35, temperature (range 350–1200 °C, time (range 2–180 hours. In the present study, the influence of such parameters affecting the nitriding layers' thickness, hardness, composition and residual stress was evaluated. The aim was to streamline the process by numerical–experimental analysis allowing to define the optimal conditions for the success of the process. The optimization software that was used is modeFRONTIER (Esteco, through which was defined a set of input parameters (steel composition, nitrogen potential, nitriding time, etc. evaluated on the basis of an optimization algorithm carefully chosen for the multi-objective analysis. The mechanical and microstructural results belonging to the nitriding process, performed with different processing conditions for various steels, are presented. The data were employed to obtain the analytical equations describing nitriding behavior as a function of nitriding parameters and steel composition. The obtained model was validated through control designs and optimized by taking into account physical and processing conditions.

  16. Process development of thin strip steel casting

    Energy Technology Data Exchange (ETDEWEB)

    Sussman, R.C.; Williams, R.S.

    1990-12-01

    An important new frontier is being opened in steel processing with the emergence of thin strip casting. Casting steel directly to thin strip has enormous benefits in energy savings by potentially eliminating the need for hot reduction in a hot strip mill. This has been the driving force for numerous current research efforts into the direct strip casting of steel. The US Department of Energy initiated a program to evaluate the development of thin strip casting in the steel industry. In earlier phases of this program, planar flow casting on an experimental caster was studied by a team of engineers from Westinghouse Electric corporation and Armco Inc. A subsequent research program was designed as a fundamental and developmental study of both planar and melt overflow casting processes. This study was arranged as several separate and distinct tasks which were often completed by different teams of researchers. An early task was to design and build a water model to study fluid flow through different designs of planar flow casting nozzles. Another important task was mathematically modeling of melt overflow casting process. A mathematical solidification model for the formation of the strip in the melt overflow process was written. A study of the material and conditioning of casting substrates was made on the small wheel caster using the melt overflow casting process. This report discusses work on the development of thin steel casting.

  17. 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.

  18. Symbiosis of Steel, Energy, and CO2 Evolution in Korea

    Science.gov (United States)

    Lee, Hyunjoung; Matsuura, Hiroyuki; Sohn, Il

    2016-09-01

    This study looks at the energy intensity of the steel industry and the greenhouse gas intensity involved with the production of steel. Using several sources of steel production data and the corresponding energy sources used provides a time-series analysis of the greenhouse gas (GHG) and energy intensity from 1990 to 2014. The impact of the steel economy with the gross domestic product (GDP) provides indirect importance of the general manufacturing sector within Korea and in particular the steel industry. Beyond 2008, the shift in excess materials production and significant increase in total imports have led to an imbalance in the Korean steel market and continue to inhibit the growth of the domestic steel market. The forecast of the GHG and energy intensity along with the steel production up to 2030 is provided using the auto regressive integrated moving average analysis.

  19. Nickel-free austenitic stainless steels for medical applications

    Directory of Open Access Journals (Sweden)

    Ke Yang and Yibin Ren

    2010-01-01

    Full Text Available The adverse effects of nickel ions being released into the human body have prompted the development of high-nitrogen nickel-free austenitic stainless steels for medical applications. Nitrogen not only replaces nickel for austenitic structure stability but also much improves steel properties. Here we review the harmful effects associated with nickel in medical stainless steels, the advantages of nitrogen in stainless steels, and emphatically, the development of high-nitrogen nickel-free stainless steels for medical applications. By combining the benefits of stable austenitic structure, high strength and good plasticity, better corrosion and wear resistances, and superior biocompatibility compared to the currently used 316L stainless steel, the newly developed high-nitrogen nickel-free stainless steel is a reliable substitute for the conventional medical stainless steels.

  20. HTPro: Low-temperature Surface Hardening of Stainless Steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lundin; Somers, Marcel A. J.

    2013-01-01

    Low-temperature surface hardening of stainless steel provides the required performance properties without affecting corrosion resistance.......Low-temperature surface hardening of stainless steel provides the required performance properties without affecting corrosion resistance....

  1. Determination of inclusions in liquid steel after calcium treatment

    CSIR Research Space (South Africa)

    Tshilombo, K

    2010-02-01

    Full Text Available Nozzle blocking was eliminated by calcium-treated liquid steel through changing the chemical and phase composition of alumina inclusions in aluminium-killed steel. Three different methods were applied to determine the composition of inclusions...

  2. Prediction of the mechanical behaviour of TRIP steel

    NARCIS (Netherlands)

    Perdahcioglu, Emin Semih; Geijselaers, Hubertus J.M.; Tekkaya, A.E.; Hirt, G.

    2011-01-01

    TRIP steel typically contains four different phases, ferrite, bainite, austenite and martensite. During deformation the metastable retained austenite tends to transform to stable martensite. The accompanying transformation strain has a beneficial effect on the ductility of the steel during forming.

  3. Corrosion behaviour of galvanized steel and electroplating steel in aqueous solution: AC impedance study and XPS

    Energy Technology Data Exchange (ETDEWEB)

    Lebrini, M.; Fontaine, G. [Laboratoire des Procedes d' Elaboration des Revetements Fonctionnels, LSPES UMR CNRS 8008, ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Gengembre, L. [Unite de Catalyse et Chimie du solide UMR 8181 Bat C3, USTL, F-59655 Villeneuve d' Ascq Cedex (France); Traisnel, M. [Laboratoire des Procedes d' Elaboration des Revetements Fonctionnels, LSPES UMR CNRS 8008, ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France)], E-mail: Michel.Traisnel@ensc-lille.fr; Lerasle, O.; Genet, N. [TOTAL France, Centre de Recherche de Solaize, Chemin du canal, BP 22, F-69360 Solaize (France)

    2008-08-30

    The efficiency of a new triazole derivative, namely, 2-{l_brace}(2-hydroxyethyl)[(4-methyl-1H-1,2,3-benzotriazol-1-yl)methyl]amino{r_brace} ethanol (TTA) has been studied for corrosion inhibition of galvanized steel and electroplating steel in aqueous solution. Corrosion inhibition was studied using electrochemical impedance spectroscopy (EIS). These studies have shown that TTA was a very good inhibitor. Data obtained from EIS show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. The corrosion behaviour of galvanized steel and electroplating steel in aqueous solution was also investigated in the presence of 4-methyl-1H-benzotriazole (TTA unsubstituted) by EIS. These studies have shown that the ability of the molecule to adsorb on the steel surface was dependent on the group in triazole ring substituent. X-ray photoelectron spectroscopy surface analysis with TTA shows that it chemisorbed on surface of galvanized steel and electroplating steel.

  4. Interaction model of steel ladle of continuous caster in steel works

    Directory of Open Access Journals (Sweden)

    Huang Bang Fu

    2016-01-01

    Full Text Available For further research on the precondition and interoperability model of interaction ladles among continuous caster, this article takes steel ladle of Y steel works as the object of research. On the basis of turnover number calculation model of single cast steel ladle, the relationship between cast number and the turnover number and turnover times and last turnover number are further analyzed. The simulation of steel ladle turnover rules was taken on the 2 continuous casters with Gantt chart. After that, the relationships between turnover number and last turnover number and non-turnover number are researched deeply. Combining with the Gantt chart, the expressions of start casting time and empty ladle ending time and heavy ladle starting time were put forward. The precondition of steel ladle interaction is obtained, which means the exchange ladle should not undertaking transport task in first stop continuous caster, and the empty ladle end time of exchange ladle of first stop continuous caster should early than the heavy ladle start time of last stop continuous caster. After applying the model to practice, 3 steel ladles of No.2 continuous caster can be reduced. This research results is supplying theoretical basis for steel ladle controlling and production organization optimization, and enriches the theory and method of metallurgical process integration.

  5. CO2 emissions in the steel industry

    Directory of Open Access Journals (Sweden)

    M. Kundak

    2009-07-01

    Full Text Available Global CO2 emissions caused by the burning of fossil fuels over the past century are presented. Taking into consideration the total world production of more than 1,3 billion tons of steel, the steel industry produces over two billion tons of CO2. Reductions in CO2 emissions as a result of technological improvements and structural changes in steel production in industrialized countries during the past 40 years are described. Substantial further reductions in those emissions will not be possible using conventional technologies. Instead, a radical cutback may be achieved if, instead of carbon, hydrogen is used for direct iron ore reduction. The cost and the ensuing CO2 generation in the production of hydrogen as a reducing agent from various sources are analysed.

  6. Application of RST in the steel industry

    Science.gov (United States)

    Raman, R. V.; Maringer, R. E.

    1982-05-01

    The rapid solidification technology (RST) involves quenching molten metals at rates of perhaps 102 to 1010 degrees C per second. First reported in 1960, RST has experienced rapid growth during the last decade and is now established on the commercial market-place. This has resulted from the simple facts that unusual properties result from RST, that relatively easy techniques are available to produce large quantities of material, and that applications for these materials have been recognized. Ferrous-base materials produced by RST methods include staple fibers of mild and stainless steel for incorporation into concrete and castable refractories, powder metallurgy tool steels, and amorphous strip for power transformers. Research results suggest that RST will have a strong continuing influence on ferrous powder metallurgy, on the direct casting of strip and foil of carbon and stainless steel, and on core materials for motor and transformers.

  7. Complex Protection of Vertical Stainless Steel Tanks

    Directory of Open Access Journals (Sweden)

    Fakhrislamov Radik Zakievich

    2014-03-01

    Full Text Available The authors consider the problem of fail-safe oil and oil products storage in stainless steel tanks and present the patented tank inner side protection technology. The latter provides process, ecological and fire safety and reducing soil evaporation of oil products, which is a specific problem. The above-mentioned technology includes corrosion protection and heat insulation protection providing increase of cover durability and RVS service life in general. The offered technological protection scheme is a collaboration of the author, Steel Paint GmbH firm and JSC “Koksokhimmontazhproyekt”. PU foam unicomponent materials of Steel Paint GmbH firm provide the protection of tank inner side and cover.

  8. Thermophysical properties of stainless steel foils

    Energy Technology Data Exchange (ETDEWEB)

    Wilkes, K.E.; Strizak, J.P.; Weaver, F.J. [Oak Ridge National Lab., TN (United States); Besser, J.E.; Smith, D.L. [Aladdin Industries, Inc. (United States)

    1997-10-01

    Evacuated panel superinsulations with very high center-of-panel thermal resistances are being developed for use in refrigerators/freezers. Attainment of high resistances relies upon the maintenance of low vacuum levels by the use of stainless steel vacuum jackets. However, the metal jackets also present a path for heat conduction around the high resistance fillers. This paper presents results of a study of the impact of metal vacuum jackets on the overall thermal performance of vacuum superinsulations when incorporated into the walls and doors of refrigerators/freezers. Results are presented on measurements of the thermophysical properties of several types and thicknesses of stainless steel foils that were being considered for application in superinsulations. A direct electrical heating method was used for simultaneous measurements of the electrical resistivity, total hemispherical emittance, and thermal conductivity of the foils. Results are also presented on simulations of the energy usage of refrigerators/freezers containing stainless-steel-clad vacuum superinsulations.

  9. Rare Earth Additions in Continuously Cast Steel

    Science.gov (United States)

    Wilson, William G.; Heaslip, L. J.; Sommerville, I. D.

    1985-09-01

    Rare earth (lanthanide metals) addiiions to continuously cast steel are particularly advantageous because of their ability to refine as-cast structures, reduce segregation and increase hot ductility at temperatures just below that of solidification. The complete shape control of sulfides in steels containing Rare Earth Metals (REM), whether continuously cast or ingot cast, is primarily responsible for improvements in ductility related mechanical properties, weldability, fatigue resistance and resistance to hydrogen damage. Complete sulfide shape control can be obtained with REM additions at sulfur levels as high as.020%. The greatest improvements, however, are obtained with REM additions to low sulfur steels. However, to achieve full operational advantages afforded by REM, nozzle blockage problems must be circumvented. Water model studies indicate a possible solution.

  10. Fatigue in Steel Structures under Random Loading

    DEFF Research Database (Denmark)

    Agerskov, Henning

    1999-01-01

    types of welded plate test specimens and full-scale offshore tubular joints. The materials that have been used are either conventional structural steel with a yield stress of ~ 360-410 MPa or high-strength steel with a yield stress of ~ 810-1010 MPa. The fatigue tests and the fracture mechanics analyses......Fatigue damage accumulation in steel structures under random loading is studied. The fatigue life of welded joints has been determined both experimentally and from a fracture mechanics analysis. In the experimental part of the investigation, fatigue test series have been carried through on various...... have been carried out using load histories, which are realistic in relation to the types of structures studied, i.e. primarily bridges, offshore structures and chimneys. In general, the test series carried through show a significant difference between constant amplitude and variable amplitude fatigue...

  11. Residual stress measurements in carbon steel

    Science.gov (United States)

    Heyman, J. S.; Min, N.

    1986-01-01

    External dc magnetic field-induced changes in natural velocity of Rayleigh surface waves were measured in steel specimens under various stress conditions. The low field slopes of curves representing the fractional changes of natural velocity were proved to provide correct stress information in steels with different metallurgical properties. The slopes of curves under uniaxial compression, exceeding about one third of the yield stress, fell below zero in all the specimens when magnetized along the stress axis. The slopes under tension varied among different steels but remained positive in any circumstances. The stress effect was observed for both applied and residual stress. A physical interpretation of these results is given based on the stress-induced domain structure changes and the delta epsilon effect. Most importantly, it is found that the influence of detailed metallurgical properties cause only secondary effects on the obtained stress information.

  12. Activity of Reducing Steel Slag of EAF

    Institute of Scientific and Technical Information of China (English)

    GUO Chinhsiang; HWANG Chaolung; LIN Tingyi

    2011-01-01

    Reducing steel slag (RSS) was mainly acquired from five electric-arc furnace (EAF)steelmaking plants (among them, the products of two plants were carbon steel and those of other plants were stainless steel) for research tests. The chemical properties, compound compositions, activities and contents of main expansive compounds were tested. The results showed that the field sampled RSS had a very high crystallinity and hydraulicity with main chemical compositions close to those of Portland cement. It can be known from the study that in case of C/S ratio higher than 2.0, the main compound compositions are C2S, C3S, C2F and f-CaO. However, after the RSS was stored for six months, an obvious variation occurred with potential pre-hydration in RSS, where the SO3 content was slightly reduced and the compressive activity index was obviously higher than that at the 28th day.

  13. Ultrasonic Spectroscopy of Stainless Steel Sandwich Panels

    Science.gov (United States)

    Cosgriff, Laura M.; Lerch, Bradley A.; Hebsur, Mohan G.; Baaklini, George Y.; Ghosn, Louis J.

    2003-01-01

    Enhanced, lightweight material systems, such as 17-4PH stainless steel sandwich panels are being developed for use as fan blades and fan containment material systems for next generation engines. In order to improve the production for these systems, nondestructive evaluation (NDE) techniques, such as ultrasonic spectroscopy, are being utilized to evaluate the brazing quality between the 17-4PH stainless steel face plates and the 17-4PH stainless steel foam core. Based on NDE data, shear tests are performed on sections representing various levels of brazing quality from an initial batch of these sandwich structures. Metallographic characterization of brazing is done to corroborate NDE findings and the observed shear failure mechanisms.

  14. New ferritic steels for advanced steam plants

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, K.H; Koenig, H. [GEC ALSTHOM Energie GmbH, Nuremberg (Germany)

    1998-12-31

    During the last 15-20 years ferritic-martensitic 9-12 % chromium steels have been developed under international research programmes which permit inlet steam temperatures up to approx. 625 deg C and pressures up to about 300 bars, thus leading to improvements in thermal efficiency of around 8 % and a CO{sub 2} reduction of about 20 % versus conventional steam parameters. These new steels are already being applied in 13 European and 34 Japanese power stations with inlet steam temperature up to 610 deg C. This presentation will give an account of the content, scope and results of the research programmes and of the experience gained during the production of components which have been manufactured from the new steels. (orig.) 13 refs.

  15. Microstructure and cleavage in lath martensitic steels

    Directory of Open Access Journals (Sweden)

    John W Morris Jr, Chris Kinney, Ken Pytlewski and Y Adachi

    2013-01-01

    Full Text Available In this paper we discuss the microstructure of lath martensitic steels and the mechanisms by which it controls cleavage fracture. The specific experimental example is a 9Ni (9 wt% Ni steel annealed to have a large prior austenite grain size, then examined and tested in the as-quenched condition to produce a relatively coarse lath martensite. The microstructure is shown to approximate the recently identified 'classic' lath martensite structure: prior austenite grains are divided into packets, packets are subdivided into blocks, and blocks contain interleaved laths whose variants are the two Kurjumov–Sachs relations that share the same Bain axis of the transformation. When the steel is fractured in brittle cleavage, the laths in the block share {100} cleavage planes and cleave as a unit. However, cleavage cracks deflect or blunt at the boundaries between blocks with different Bain axes. It follows that, as predicted, the block size governs the effective grain size for cleavage.

  16. EIS Response of MIC on Carbon Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Maahn, Ernst

    1998-01-01

    Abstract Microbially influenced corrosion of carbon steel under sulphate reducing (sulphide-producing) bacterial activity (SRB) results in the formation of both ferrous sulphides as well as biofilm on the metal surface. The electrochemical characteristics of the ferrous sulphide/steel interface...... as compared to the biofilm/ferrous sulphide/steel interface has been studied with EIS, DC polarisations (Tafel, LPR) and a potentiostatic step technique. The electrochemical response is related to a threshold sulphide concentration above which very characteristic changes such as indications of finite...... diffusion and high interfacial capacitance appear. These effects are strongly enhanced in the biologically active environment as compared to the sterile solutions possibly due to an enhanced porosity in the biofilm/ferrous sulphide surface layers. The effect of these features is that EIS may be used...

  17. Processing of Ultralow Carbon Pipeline Steels with Acicular Ferrite

    Institute of Scientific and Technical Information of China (English)

    Furen XIAO; Mingchun ZHAO; Yiyin SHAN; Bo LIAO; Ke YANG

    2004-01-01

    Acicular ferrite microstructure was achieved for an ultralow carbon pipeline steel through the improved thermomechanical control process (TMCP), which was based on the transformation process of deformed austenite of steel.Compared with commercial pipeline steels, the experimental ultralow carbon pipeline steel possessed the satisfied strength and toughness behaviors under the current improved TMCP, although it contained only approximately 0.025% C, which should mainly be attributed to the microstructural characteristics of acicular ferrite.

  18. Durability of light steel framing in residential applications

    OpenAIRE

    Lawson, RM; Popo-Ola, S.O.; Way, A.; Heatley, T; Pedreschi, Remo

    2010-01-01

    This paper presents a summary and analysis of research findings on the durability of galvanised cold-formed steel sections used in housing in order to deduce their design life. These cold-formed sections are produced from pre-galvanised strip steel. It reviews reports and publications from research projects carried out by Corus and the Steel Construction Institute on zinc-coated, cold-formed steel products. New data have also been gathered from measurements on houses and similar buildings tha...

  19. Mean Reversion with Drift and Real Options in Steel Industry

    OpenAIRE

    Luiz de Magalhães Ozorio; Carlos de Lamare Bastian-Pinto; Tara Nanda Baidya; Luiz Eduardo Teixeira Brandão

    2012-01-01

    Steel is a commodity with significant price volatility and the choice of stochastic process that better describes its price performance is a fundamental issue in real options valuation in steel industry projects. As verified with other commodities, it is assumed that steel prices can be led partially by a mean reversion component, but the analysis of some economic issues related to production indicates that steel prices may also have a rising drift component. This, in practical terms, would i...

  20. Microstructure formation and properties of abrasion resistant cast steel

    OpenAIRE

    S. Parzych; Krawczyk, J.

    2010-01-01

    The so-called adamitic cast steels are characterised by a high abrasion resistance. These cast steels are of a pearlitic matrix with uniformly distributed hypereutectoid cementite precipitates. Apart from hypereutectoid cementite very often transformed ledeburite also occurs in the microstructure of these cast steels. Such cast steels contain chromium (app. 1 %) and nickel (app. 0.5 %) as alloy additions and sometimes their silicon content is increased. The presence of molybdenum is also perm...

  1. Enhanced Inclusion Removal from Steel in the Tundish

    Energy Technology Data Exchange (ETDEWEB)

    R. C. Bradt; M.A.R. Sharif

    2009-09-25

    The objective of this project was to develop an effective chemical filtering system for significantly reducing the content of inclusion particles in the steel melts exiting the tundish for continuous casting. This project combined a multi-process approach that aimed to make significant progress towards an "inclusion free" steel by incorporating several interdependent concepts to reduce the content of inclusions in the molten steel exiting the tundish for the caster. The goal is to produce "cleaner" steel.

  2. Enhanced Incluison Removal from Steel in the Tundish

    Energy Technology Data Exchange (ETDEWEB)

    R.C. Bradt; M.A.R. Sharif

    2009-09-25

    The objective of this project was to develop an effective chemical filtering system for significantly reducing the content of inclusion particles in the steel melts exiting the tundish for continuous casting. This project combined a multi-process approach that aimed to make significant progress towards an "inclusion free" steel by incorporating several interdependent concepts to reduce the content of inclusions in the molten steel exiting the tundish for the caster. The goal is to produce "cleaner" steel.

  3. Investigation of the plastic fracture of high strength steels

    Science.gov (United States)

    Cox, T. B.; Low, J. R., Jr.

    1972-01-01

    This investigation deals in detail with the three recognized stages of plastic fracture in high strength steels, namely, void initiation, void growth, and void coalescence. The particular steels under investigation include plates from both commercial purity and high purity heats of AISI 4340 and 18 Ni, 200 grade maraging steels. A scanning electron microscope equipped with an X-ray energy dispersive analyzer, together with observations made using light microscopy, revealed methods of improving the resistance of high strength steels to plastic fracture.

  4. Thermodynamic Analysis on Precipitated Phases in Low Activation Steel

    OpenAIRE

    PANG Qi-hang; TANG Di; ZHAO Zheng-zhi; WU Hui-bin; Li, Shuo

    2016-01-01

    A type of low-carbon reduced activation ferritic/martensitic (RAFM) steel is designed.The microstructure and mechanical properties of tested steels prepared by different technologies were investigated by means of scanning electron microscope, transmission electron microscope and tensile test. The chemical composition of precipitations of tested steels are inspected by energy dispersive spectroscopy (EDS), meanwhile the law of precipitation phase of low carbon low activation FM steel was studi...

  5. 嗜麦芽寡养单胞菌降解羽毛5L发酵罐工业小试过程研究%Study on Stenotrophomonas maltophilia DHHJ fermentation in5 L fermenter pilot plant

    Institute of Scientific and Technical Information of China (English)

    鲁丹; 曹张军; 周美华

    2009-01-01

    In order to industrialize the utilization of waste feather by microbiological method,the scale-upof fermentation from shaking flask to 5 L fermenter for Stenotrophomonas maltophilia DHHJ based on the study of fermentation in erlenmeyer flask was investigated.Further,this paper analyzed the fermentation process and optimized the technological parameters.The changes of material and energy in metabolic processes were conjectured,and the product formation of DHHJ batch fermentation kinetics was studied.Finally,under the circumstances of O.08 MPa pressure,2.5 L/min air flow.defined temperature of 40 ℃ and other controlled conditions,this yield was 1~2 fold higher in comparison with the shaking flask fermentation,fermentation period shortened by one day.And it provided the reliable basis for the use of the feather waste.%为了将微生物处理羽毛工艺产业化,在摇瓶发酵条件优化的基础上进行5 L发酵罐工业小试研究,确定了放大发酵条件并根据发酵条件记录对发酵过程进行分析,推测代谢过程中的物质及能量变化及产物形成的动力学模型.在通气气压为0.08 MPa,空气流量为2.5 L/min及恒温40℃的条件下,产物得率比摇瓶发酵提高了2~3倍,发酵周期缩短了l d.为羽毛废弃物的利用提供了可靠的依据.

  6. Duplex Stainless Steels-An overview

    Directory of Open Access Journals (Sweden)

    Dr. Sunil D.Kahar

    2017-04-01

    Full Text Available Stainless steel is one of the most important materials in the engineering world. The material‟s wide applications in chemical, petrochemical, off-shore, and power generation plants prove that it is one of the most reliable materials. The Newest fast growing family of stainless steels is duplex alloys. The ferritic-austenitic grades have a ferrite matrix intermix with austenite and in other words island of austenite in a continuous matrix of highly alloyed ferrite commonly called „Duplex‟ stainless steel. Duplex stainless steel covers ferritic/austenitic Fe-Cr-Ni alloy with between 30% to 70 % Ferrite .Due to high level of Cr, Mo, and N steels shows high pitting & stress corrosion cracking resistance in chloride-containing environments. Hence it is frequently used in oilrefinery heat exchangers & typical applications where there is a risk for SCC and localized corrosion as a result of chloride-containing process streams, cooling waters or deposits. Modern duplex stainless steels have generally good Weldability. Due to a balanced composition, where nitrogen plays an important role, austenite formation in the heat affected zone (HAZ and weld metal is rapid. Under normal welding conditions a sufficient amount of austenite is formed to maintain good resistance to localized corrosion where as too rapid cooling may result in excessive amounts of ferrite, reducing the toughness. Therefore, welding with low heat input in thick walled materials should be avoided. Welding methods, such as resistance welding, laser welding and electron beam welding, which cause extremely rapid cooling should also be avoided or used with extreme caution. Too slow cooling can in the higher alloyed duplex grades cause formation of inter-metallic phases detrimental to corrosion resistance and toughness.

  7. Identification of Relevant Work Parameters of Ladle Furnace While Melting the High Ductility Steel and High-Carbon Steel

    Directory of Open Access Journals (Sweden)

    Warzecha M.

    2016-03-01

    Full Text Available In the present paper, secondary metallurgical treatment in ladle furnace during smelting the high carbon steel and steel with improved ductility for cold-deforming, under industrial conditions were analyzed.

  8. Experimental and Theoretical Investigations of Hot Isostatically Pressed-Produced Stainless Steel/High Alloy Tool Steel Compound Materials

    Science.gov (United States)

    Lindwall, Greta; Flyg, Jesper; Frisk, Karin; Sandberg, Odd

    2011-05-01

    Consolidation of tool steel powders and simultaneous joining to a stainless 316L steel are performed by hot isostatic pressing (HIP). Two tool steel grades are considered: a high vanadium alloyed carbon tool steel, and a high vanadium and chromium alloyed nitrogen tool steel. The boundary layer arising during diffusion bonding is in focus and, in particular, the diffusion of carbon and nitrogen over the joint. Measurements of the elemental concentration profiles and corrosion tests by the double loop-electrochemical potentiokinetic reactivation (DL-EPR) method are performed. Comparative calculations with the DICTRA software are performed and are found to be in agreement with the experimental results. It is found that the carbon tool steel grade has a more critical influence on the corrosion resistance of the stainless 316L steel in comparison to the nitrogen tool steel grade.

  9. 77 FR 1504 - Stainless Steel Wire Rod From India

    Science.gov (United States)

    2012-01-10

    ... COMMISSION Stainless Steel Wire Rod From India Determination On the basis of the record \\1\\ developed in the... antidumping duty order on stainless steel wire rod From India would be likely to lead to continuation or... contained in USITC Publication 4300 (January 2012), entitled Stainless Steel Wire Rod From...

  10. Explosive welding technique for joining aluminum and steel tubes

    Science.gov (United States)

    Wakefield, M. E.

    1975-01-01

    Silver sheet is wrapped around aluminum portion of joint. Mylar powder box is wrapped over silver sheet. Explosion welds silver to aluminum. Stainless-steel tube is placed over silver-aluminum interface. Mylar powder box, covered with Mylar tape, is wrapped around steel member. Explosion welds steel to silver-aluminum interface.

  11. 78 FR 7452 - Steel Wire Garment Hangers From Vietnam; Determinations

    Science.gov (United States)

    2013-02-01

    ... COMMISSION Steel Wire Garment Hangers From Vietnam; Determinations On the basis of the record \\1\\ developed... imports of steel wire garment hangers from Vietnam, provided for in subheading 7326.20.00 of the... countervailing and antidumping duty orders on steel wire garment hangers from Vietnam. Background The...

  12. 77 FR 28404 - Galvanized Steel Wire From China and Mexico

    Science.gov (United States)

    2012-05-14

    ... COMMISSION Galvanized Steel Wire From China and Mexico Determinations On the basis of the record \\1... retarded, by reason of imports from Mexico of galvanized steel wire, provided for in subheadings 7217.20.30... galvanized steel wire from China and Mexico were sold at LTFV within the meaning of 733(b) of the Act (19...

  13. 76 FR 29266 - Galvanized Steel Wire From China and Mexico

    Science.gov (United States)

    2011-05-20

    ... COMMISSION Galvanized Steel Wire From China and Mexico Determinations On the basis of the record \\1... injured by reason of imports from China and Mexico of galvanized steel wire, provided for in subheading... subsidized imports of galvanized steel wire from China and Mexico. Accordingly, effective March 31, 2011,...

  14. 49 CFR 192.105 - Design formula for steel pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Design formula for steel pipe. 192.105 Section 192... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.105 Design formula for steel pipe. (a) The design pressure for steel pipe is determined in accordance with the following...

  15. 49 CFR 192.309 - Repair of steel pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Repair of steel pipe. 192.309 Section 192.309... Lines and Mains § 192.309 Repair of steel pipe. (a) Each imperfection or damage that impairs the serviceability of a length of steel pipe must be repaired or removed. If a repair is made by grinding, the...

  16. Low temperature gaseous surface hardening of stainless steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2011-01-01

    The present contribtion gives an overview of some of the technological aspects of low temperature thermochemical treatment of stainless steel. Examples of low temperature gaseous nitriding, carburising and nitrocarburising of stainless steel are presented and discussed. In particular......, the morphology, microstructure and characteristics of so-called expanded austenite "layers" on stainless steel are addressed....

  17. Low temperature gaseous surface hardening of stainless steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2010-01-01

    The present contribution gives an overview of some of the technological aspects of low temperature thermochemical treatment of stainless steel. Examples of low temperature gaseous nitriding, carburising and nitrocarburising of stainless steel are presented and discussed. In particular......, the morphology, microstructure and characteristics of so-called expanite “layers” on stainless steel are addressed....

  18. Activation and Dose Rate Analysis of 316 Stainless Steel

    Institute of Scientific and Technical Information of China (English)

    XU; Zhi-long; SUN; Zheng; LIU; Xing-min; WAN; Hai-xia

    2012-01-01

    <正>In order to conduct research on 316 stainless steel to be used in reactors, neutron activation during irradiation and dose rate after irradiation in China Experiment Fast Reactor (CEFR) are calculated and analyzed. Based on 1 g of 316 stainless steel specimen, analysis on the activity of 316 stainless steel irradiated

  19. Study of hot hardness characteristics of tool steels

    Science.gov (United States)

    Chevalier, J. L.; Dietrich, M. W.; Zaretsky, E. V.

    1972-01-01

    Hardness measurements of tool steel materials in electric furnace at elevated temperatures and low oxygen environment are discussed. Development of equation to predict short term hardness as function of intial room temperature hardness of steel is reported. Types of steel involved in the process are identified.

  20. 46 CFR 154.195 - Aluminum cargo tank: Steel enclosure.

    Science.gov (United States)

    2010-10-01

    ... published in “Rules for Building and Classing Steel Vessels”, 1981. (c) The steel cover for the aluminum... 46 Shipping 5 2010-10-01 2010-10-01 false Aluminum cargo tank: Steel enclosure. 154.195 Section... CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction...

  1. Friction Stir Spot Welding of Advanced High Strength Steels

    Energy Technology Data Exchange (ETDEWEB)

    Santella, M. L.; Hovanski, Yuri; Grant, Glenn J.; Carpenter, Joseph A.; Warren, C. D.; Smith, Mark T.

    2008-12-28

    Experiments are continuing to evaluate the feasibility of friction stir spot welding advanced high-strength steels including, DP780, martensitic hot-stamp boron steel, and TRIP steels. Spot weld lap-shear strengths can exceed those required by industry standards such as AWS D8.1.

  2. 49 CFR Appendix A to Part 178 - Specifications for Steel

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Specifications for Steel A Appendix A to Part 178.... 178, App. A Appendix A to Part 178—Specifications for Steel Table 1 Designation Chemical composition... ladle analysis may be 1.40 percent. 6 Rephosphorized Grade 3 steels containing no more than 0.15...

  3. 49 CFR 192.371 - Service lines: Steel.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Steel. 192.371 Section 192.371 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... § 192.371 Service lines: Steel. Each steel service line to be operated at less than 100 p.s.i. (689...

  4. 21 CFR 878.4495 - Stainless steel suture.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Stainless steel suture. 878.4495 Section 878.4495...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4495 Stainless steel suture. (a) Identification. A stainless steel suture is a needled or unneedled nonabsorbable surgical suture composed of...

  5. 78 FR 11090 - Steel Import Monitoring and Analysis System

    Science.gov (United States)

    2013-02-15

    ... International Trade Administration 19 CFR Part 360 RIN 0625-AA93 Steel Import Monitoring and Analysis System... to extend the Steel Import Monitoring and Analysis (SIMA) system until March 21, 2017. The purpose of the SIMA system is to provide the public statistical data on steel imports entering the United...

  6. 77 FR 67593 - Steel Import Monitoring and Analysis System

    Science.gov (United States)

    2012-11-13

    ... International Trade Administration 19 CFR Part 360 RIN 0625-AA93 Steel Import Monitoring and Analysis System... modifications to the regulations for the Steel Import Monitoring and Analysis (SIMA) System that would extend... as possible certain steel mill imports into the United States and make the import data...

  7. 21 CFR 872.3350 - Gold or stainless steel cusp.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gold or stainless steel cusp. 872.3350 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3350 Gold or stainless steel cusp. (a) Identification. A gold or stainless steel cusp is a prefabricated device made of austenitic alloys or...

  8. Mathematical modeling of steel fiber concrete under dynamic impact

    Science.gov (United States)

    Belov, N. N.; Yugov, N. T.; Kopanitsa, D. G.; Kopanitsa, G. D.; Yugov, A. A.; Shashkov, V. V.

    2015-01-01

    This paper introduces a continuum mechanics mathematical model that describes the processes of deformation and destruction of steel-fiber-concrete under a shock wave impact. A computer modeling method was applied to study the processes of shock wave impact of a steel cylindrical rod and concrete and steel fiber concrete plates. The impact speeds were within 100-500 m/s.

  9. Micronutrient availability from steel slag amendment in pine bark substrates

    Science.gov (United States)

    Steel slag is a byproduct of the steel industry that can be used as a liming agent, but also has a high mineral nutrient content. While micronutrients are present in steel slag, it is not known if the mineral form of the micronutrients would render them available for plant uptake. The objective of...

  10. Advanced analysis for structural steel building design

    Institute of Scientific and Technical Information of China (English)

    Wai Fah CHEN

    2008-01-01

    The 2005 AISC LRFD Specifications for Structural Steel Buildings are making it possible for designers to recognize explicitly the structural resistance provided within the elastic and inelastic ranges of beha-vior and up to the maximum load limit state. There is an increasing awareness of the need for practical second-order analysis approaches for a direct determination of overall structural system response. This paper attempts to present a simple, concise and reasonably comprehens-ive introduction to some of the theoretical and practical approaches which have been used in the traditional and modern processes of design of steel building structures.

  11. Stainless Steel Microstructure and Mechanical Properties Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Switzner, Nathan T

    2010-06-01

    A nitrogen strengthened 21-6-9 stainless steel plate was spinformed into hemispherical test shapes. A battery of laboratory tests was used to characterize the hemispheres. The laboratory tests show that near the pole (axis) of a spinformed hemisphere the yield strength is the lowest because this area endures the least “cold-work” strengthening, i.e., the least deformation. The characterization indicated that stress-relief annealing spinformed stainless steel hemispheres does not degrade mechanical properties. Stress-relief annealing reduces residual stresses while maintaining relatively high mechanical properties. Full annealing completely eliminates residual stresses, but reduces yield strength by about 30%.

  12. Erosion behavior and mechanism of boronised steels

    Institute of Scientific and Technical Information of China (English)

    刘立; 凌国平; 刘涛; 郦剑

    2002-01-01

    Boronising of steels is a hardening process to get high surface hardness. The erosion resistance of boronised steels was researched with the use of four kinds of erodent, i.e. glass, alumina, quartz and silicon carbide. The erosion rate increases rapidly with erodent hardness and severe erosion occurs with high impacting angle range of hard particles. SEM analysis indicated that chipping is caused by repetitive impacting of glass and quartz, whereas by alumina and silicon carbide impacting, chipping, and that plastic flow take place simultaneously and the erosion rate reaches the peak value when the impacting angle is above 60°.

  13. Erosion behavior and mechanism of boronised steels

    Institute of Scientific and Technical Information of China (English)

    刘立; 凌国平; 刘涛; 郦剑

    2002-01-01

    Boronising of steels is a hardening process to get high surfaoe hardness. The erosion resis-tance of boronised steels was researched with the use of four kinds of erodent, i.e. glass, alumina,quartz and silicon carbide. The erosion rate increases rapidly with erodent hardness and severe erosion occurs with high impacting angle range of hard particles. SEM analysis indicated that chipping is caused by repetitive impacting of glass and quartz, whereas b.y alumina and silicon carbide impacting, chipping,and that plastic flow .take place simultaneously and the erosion rate reaches the peak value when the impacting angle is above 60°.

  14. THE BAINITIC STEELS FOR RAILS APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Ivo Hlavatý

    2009-10-01

    Full Text Available Actual trends of worldwide railway transport development are characterized by increasing speed and growth of railway’s axels load. Increasing load together with transverse, longitudinal wheel displacement and braking on the rails results into heavy surface tension. One of many applications for bainitic steel is in railway transport for highly strength and wear resistant rails. Rail steel must be designed to be able to resist plastic deformation, wear, rolling contact fatigue, bending stress and thermal stress during rail welding process and rails resurfacing.

  15. Creep Resistance of VM12 Steel

    Directory of Open Access Journals (Sweden)

    Zieliński A.

    2016-09-01

    Full Text Available This article presents selected material characteristics of VM12 steel used for elements of boilers with super- and ultra-critical steam parameters. In particular, abridged and long-term creep tests with and without elongation measurement during testing and investigations of microstructural changes due to long-term impact of temperature and stress were carried out. The practical aspect of the use of creep test results in forecasting the durability of materials operating under creep conditions was presented. The characteristics of steels with regard to creep tests developed in this paper are used in assessment of changes in functional properties of the material of elements operating under creep conditions.

  16. Molybdenum protective coatings adhesion to steel substrate

    Science.gov (United States)

    Blesman, A. I.; Postnikov, D. V.; Polonyankin, D. A.; Teplouhov, A. A.; Tyukin, A. V.; Tkachenko, E. A.

    2017-06-01

    Protection of the critical parts, components and assemblies from corrosion is an urgent engineering problem and many other industries. Protective coatings’ forming on surface of metal products is a promising way of corrosionprevention. The adhesion force is one of the main characteristics of coatings’ durability. The paper presents theoretical and experimental adhesion force assessment for coatings formed by molybdenum magnetron sputtering ontoa steel substrate. Validity and reliability of results obtained by simulation and sclerometry method allow applying the developed model for adhesion force evaluation in binary «steel-coating» systems.

  17. Reactor Structural Materials: Reactor Pressure Vessel Steels

    Energy Technology Data Exchange (ETDEWEB)

    Chaouadi, R

    2000-07-01

    The objectives of SCK-CEN's R and D programme on Rector Pressure Vessel (RPV) Steels are:(1) to complete the fracture toughness data bank of various reactor pressure vessel steels by using precracked Charpy specimens that were tested statically as well as dynamically; (2) to implement the enhanced surveillance approach in a user-friendly software; (3) to improve the existing reconstitution technology by reducing the input energy (short cycle welding) and modifying the stud geometry. Progress and achievements in 1999 are reported.

  18. 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.

  19. Nondestructive Technique To Assess Embrittlement In Steels

    Science.gov (United States)

    Allison, Sidney G.; Yost, William T.; Cantrell, John H.

    1990-01-01

    Recent research at NASA Langley Research Center led to identification of nondestructive technique for detection of temper embrittlement in HY80 steel. Measures magnetoacoustic emission associated with reversible motion of domain walls at low magnetic fields. Of interest to engineers responsible for reliability and safety of various dynamically loaded and/or thermally cycled steel parts. Applications include testing of landing gears, naval vessels, and parts subjected to heat, such as those found in steam-pipe fittings, boilers, turbine rotors, and nuclear pressure vessels.

  20. STUDY OF OPERATION OF ARC STEEL FURNACE WITH CONOID BAY FLUSHING OF STEEL

    Directory of Open Access Journals (Sweden)

    M. A. Murikov

    2008-01-01

    Full Text Available The construction of the arc steel-furnace bay, the application of which allows to increase the speed of flush outflow, to provide reduction of the slag carry-over with metal, is offered.

  1. Atmospheric Corrosion of Q235 Carbon Steel and Q450 Weathering Steel in Turpan,China

    Institute of Scientific and Technical Information of China (English)

    Qiang YU; Chao-fang DONG; Yue-hua FANG; Kui XIAO; Chun-yun GUO; Gang HE; Xiao-gang LI

    2016-01-01

    Q235 carbon steel and Q450 weathering steel were exposed to the hot and dry environment of Turpan, China for three years.The corrosion rates of both steels were calculated and compared.The morphologies of the rust layer products were observed by optical microscopy and scanning electron microscopy.Analyses of the rust layers were performed by X-ray photoelectron spectroscopy,X-ray powder diffraction,and Raman spectroscopy,and anal-ysis results indicate that the compositions of rust are main iron rich oxide such as FeOOH,Fe3 O4 ,and Fe2 O3 .The iron oxide layer content proportion was calculated through a semi-quantitative algorithm.The resistance elements (Cr,Ni,and Cu)enhanced the resistance properties of the Q450 weathering steel matrix.Moreover,the resistance elements increased the proportion of goethite crystals in the corroded rust layer.

  2. Digital expression profiling identifies RUNX2, CDC5L, MDM2, RECQL4, and CDK4 as potential predictive biomarkers for neo-adjuvant chemotherapy response in paediatric osteosarcoma.

    Directory of Open Access Journals (Sweden)

    Jeffrey W Martin

    Full Text Available Osteosarcoma is the most common malignancy of bone, and occurs most frequently in children and adolescents. Currently, the most reliable technique for determining a patients' prognosis is measurement of histopathologic tumor necrosis following pre-operative neo-adjuvant chemotherapy. Unfavourable prognosis is indicated by less than 90% estimated necrosis of the tumor. Neither genetic testing nor molecular biomarkers for diagnosis and prognosis have been described for osteosarcomas. We used the novel nanoString mRNA digital expression analysis system to analyse gene expression in 32 patients with sporadic paediatric osteosarcoma. This system used specific molecular barcodes to quantify expression of a set of 17 genes associated with osteosarcoma tumorigenesis. Five genes, from this panel, which encoded the bone differentiation regulator RUNX2, the cell cycle regulator CDC5L, the TP53 transcriptional inactivator MDM2, the DNA helicase RECQL4, and the cyclin-dependent kinase gene CDK4, were differentially expressed in tumors that responded poorly to neo-adjuvant chemotherapy. Analysis of the signalling relationships of these genes, as well as other expression markers of osteosarcoma, indicated that gene networks linked to RB1, TP53, PI3K, PTEN/Akt, myc and RECQL4 are associated with osteosarcoma. The discovery of these networks provides a basis for further experimental studies of role of the five genes (RUNX2, CDC5L, MDM2, RECQL4, and CDK4 in differential response to chemotherapy.

  3. Bake hardening behavior of TRIP and DP steels

    Institute of Scientific and Technical Information of China (English)

    Jicheng Zhang; Renyu Fu; Mei Zhang; Rendong Liu; Xicheng Wei; Lin Li

    2008-01-01

    The bake hardening (BH) behavior of transformation-induced plasticity (TRIP) and dual-phase (DP) steels after different prestrains was studied. The experimental results indicate that TRIP steel exhibits good BH ability while DP steel does not, and prestrain displays a strong effect on the BH values of both steels. The comparison of microstructures of the two steels showed that the hard second phase in the matrix might be harmful to the BH ability. For deformed specimens, baking resulted in a loss of uniform elongation, but there was no obvious decrease in uniform elongation for unprestrained specimens.

  4. 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.

  5. Characteristics of modified martensitic stainless steel surfaces under tribocorrosion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rozing, Goran [Osijek Univ. (Croatia). Chair of Mechanical Engineering; Marusic, Vlatko [Osijek Univ. (Croatia). Dept. of Engineering Materials; Alar, Vesna [Zagreb Univ. (Croatia). Dept. Materials

    2017-04-01

    Stainless steel samples were tested in the laboratory and under real conditions of tribocorrosion wear. Electrochemical tests were also carried out to verify the corrosion resistance of modified steel surfaces. Metallographic analysis and hardness testing were conducted on stainless steel samples X20Cr13 and X17CrNi16 2. The possibilities of applications of modified surfaces of the selected steels were investigated by testing the samples under real wear conditions. The results have shown that the induction hardened and subsequently nitrided martensitic steels achieved an average wear resistance of up to three orders of magnitude higher as compared to the delivered condition.

  6. Influence of Blowing of Argon on the Cleanness of Steel

    Directory of Open Access Journals (Sweden)

    Pribulová A.

    2012-09-01

    Full Text Available The mechanical properties of steel components are controlled by the chemical composition and mechanical treatment to which the steel is submitted. Non-metallic inclusions have a very high influence on the steel quality but secondary metallurgy enables to reduce their content in the steel. Possibilities of secondary metallurgy are relatively extensive but financial situation in Slovak foundries does not enable to make investments in secondary metallurgy in the near future. Accessible means for influencing of steel quality is injection of an inert gas.

  7. Developing of robot flexible processing system for shipbuilding profile steel

    Institute of Scientific and Technical Information of China (English)

    姚舜; 邱涛; 楼松年; 王宏杰

    2003-01-01

    A robot flexible processing system of shipbuilding profile steel was developed. The system consists of computer integrated control and robot. An off-line programming robot was used for marking and cutting of shipbuilding profile steel. In the system the deformation and position error of profile steel can be detected by precise sensors, and figure position coordinate error resulted from profile steel deformation can be compensated by modifying traveling track of robotic arm online. The practical operation results show that the system performance can meet the needs of profile steel processing.

  8. New microalloyed steel applications for the automotive sector

    Energy Technology Data Exchange (ETDEWEB)

    Matlock, D.K.; Krauss, G.; Speer, J.G. [Advanced Steel Processing and Products Research Center, Colorado School of Mines, Golden, CO (United States)

    2005-07-01

    Developments related to the use of microalloy additions, primarily of Ti, Nb, and V, and controlled processing are reviewed to illustrate how steels with tailored microstructures and properties are produced from either bar or sheet steels for new automotive components. Microalloying additions are shown to control the necessary strengthening mechanisms to produce high strength materials with the desired toughness or formability for a specific application. Selected examples of direct cooled forging steels, microalloyed carburizing steels, and advanced high strength sheet (AHSS) steels are discussed. (orig.)

  9. Inclusion and Bubble in Steel--A Review

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li-feng

    2006-01-01

    The type, morphology and sources of inclusion in steels, including indigenous and exogenous inclusions, were discussed and reviewed. Indigenous inclusions are deoxidation products or inclusions precipitated during cooling and solidification of steel. Exogenous inclusions arise primarily from the incidental chemical (reoxidation) and mechanical interaction of liquid steel with its surroundings (slag entrainment and erosion of lining refractory). Types and causes for the nozzle clogging were also summarized. Reasons for bubble formation and bubble size distribution in steels were discussed thereafter. Finally, morphology and causes of inclusion-related defects in continuously cast steel products were reviewed, such as flange cracking in cans, slag spots and line defects on strips.

  10. Mechanism of an acoustic wave impact on steel during solidification

    Directory of Open Access Journals (Sweden)

    K. Nowacki

    2013-04-01

    Full Text Available Acoustic steel processing in an ingot mould may be the final stage in the process of quality improvement of a steel ingot. The impact of radiation and cavitation pressure as well as the phenomena related to the acoustic wave being emitted and delivered to liquid steel affect various aspects including the internal structure fragmentation, rigidity or density of steel. The article provides an analysis of the mechanism of impact of physical phenomena caused by an acoustic wave affecting the quality of a steel ingot.

  11. Development of a New Kind of High Strength Spring Steel

    Institute of Scientific and Technical Information of China (English)

    Dexiang XU; Zhongda YIN; Defu LIU

    2004-01-01

    A new kind of high strength, high toughness and high plasticity spring steel has been developed. The strength, the reduction of area and the elongation of the steel are all higher than those of the steel 60Si2CrVA. The decarburization resistance and the sag resistance are also higher than those of the steel 60Si2CrVA. It has good hardenability, and is suitable for making springs with big cross section. The bogie springs made of this kind of steel have passed 2×106 cycles without broken under the conditions of maximum stress of 906 MPa and the minimum stress of 388 MPa.

  12. HSZ 220 and 260 steel with excellent stretch formability

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, G.; Heckelmann, I.; Menne, M. [Thyssenkrupp Stahl AG, Duisburg (Germany)

    2000-07-01

    As has been shown in the stretch forming and deep drawing tests, the newly developed HSZ steels are particularly suitable for the production of large exposed car body parts, such as roofs, doors and hoods. They are rather unfavourable for applications required higher drawing depths. Owing to its excellent strain hardening behaviour and a relatively high yield strength, the HSZ steel grades exhibits a good dent resistance. For weight reduction purposes, it is possible to replace soft aluminium-killed steels or IF steels by HSZ steels with reduced sheet thicknesses. If corrosion protection is required, HSZ grades are also available electrogalvanized. (orig.)

  13. Cladding of High Mn Steel on Low C Steel by Explosive Welding

    OpenAIRE

    ACARER, Mustafa

    2014-01-01

    High Mn steel containing about 16% Mn was cladded to a low C steel by explosive welding. The experimental results showed that the bonding interface has a wavy morphology; the welding interface has the characteristics of both sharp transition and local melted zones between 2 metals. Hardness increased near the welding interface due to excess plastic deformation in the explosion area and phase transformation from g (f.c.c.) to a (b.c.c.).

  14. Ultrasonic inspection for circumferential butt joint of austenitic stainless steel with carbon steel

    Institute of Scientific and Technical Information of China (English)

    Wan Shengyun; Xiong Lasen

    2006-01-01

    Tthe practical application of ultrasonic wave inspection in welded joint by austenitic stainless steel with carbon steel is presented. It is shown from the experimental results that the high frequency narrow-pulsed longitudinal ultrasonic wave inspection technique can detect the defects in deferent sound path and location within the tested welded joint clearly and exactly. The study in the paper may provide a new approach for further application of ultrasonic inspection in coarse-grained materials.

  15. STEEL FIBER CURVATURE IN CONCRETE COMPOSITES: MODULUS PREDICTIONS USING EFFECTIVE STEEL FIBER PROPERTIES

    OpenAIRE

    Abdellatif Selmi

    2014-01-01

    Results in the literature demonstrate that substantial improvements in the mechanical behavior of concrete have been attained through the addition of steel fibers as a reinforcing phase. We have developed a model combining finite element results and micromechanical methods to determine the effective reinforcing modu-lus of hook-ended steel fibers. This effective reinforcing modulus is then used within a multiphase micro-mechanics model to predict the effective modulus of concrete reinforced w...

  16. Demonstrating Nonhexavelent Chrome Steel Conversion Coatings on Stryker High Hard Armor Steel Hatches

    Science.gov (United States)

    2014-01-01

    embrittlement are as follows: 1. Any ferrous -based alloy exhibiting hardness greater than Rc35 (e.g., high-strength steel) requires testing and heat...section is based on the findings from WP-1521. Most of the conversion coating work thus far has focused on the use of TCP on aluminum alloys . In...recent years, TCP has enjoyed good success on aluminum. However, for steel alloys and phosphated surfaces, further development is needed. One of the

  17. Effect of thermomechanical processing on microstructure, texture, and anisotropy in two Nb microalloyed steels

    Science.gov (United States)

    Akbarzadeh, Abbas

    The process parameters that affect the anisotropy of mechanical properties of two Nb microalloyed linepipe steels (grades X-70 and X-80) were examined by controlled rolling and accelerated cooling on a pilot mill. The rolling schedules were first simulated by multi-pass torsion testing so as to determine the critical temperatures, such as Tsbnr and Arsb3. Using the torsion test results, two finish rolling temperatures were chosen so as to be above and below the Asb3 (in the gamma + alpha region). Two reheat temperatures were selected to study the effect of prior austenite grain size. The properties of air cooled samples are compared with those of specimens cooled at two different rates; in each case, cooling was interrupted at one of three different temperatures. The textures were measured by x-ray diffractometry and are presented in the form of ODF plots and skeleton lines. The yield strengths were measured by carrying out tensile tests along directions inclined at increasing angles to the rolling direction. The state of the pancaked austenite before transformation was characterized in terms of the effective interfacial area. It is shown that this parameter determines the sharpness of the transformation texture because it accounts for both the amount of pancaking strain applied to the austenite before transformation and the austenite grain size. Another important factor affecting texture development during transformation is the rate of cooling, as it determines the dislocation density present on each active slip system. The results of hardness testing, texture measurement, and mechanical testing showed that a moderate cooling rate and a medium cooling interruption temperature lead to the best combination of a fine microstructure and a desirable texture. It is shown that accelerated cooling increases both the yield strength and the planar anisotropy of the yield strength, the latter property rising to a maximum in the samples associated with the lowest cooling

  18. Hydrogen induced plastic deformation of stainless steel

    NARCIS (Netherlands)

    Gadgil, V.J.; Keim, Enrico G.; Geijselaers, Hubertus J.M.

    1998-01-01

    Hydrogen can influence the behaviour of materials significantly. The effects of hydrogen are specially pronounced in high fugacities of hydrogen which can occur at the surface of steels in contact with certain aqueous environments. In this investigation the effect of high fugacity hydrogen on the

  19. Case studies of steel structure failures

    Directory of Open Access Journals (Sweden)

    P. Bernasovský

    2010-01-01

    Full Text Available The contribution deals with some case studies of steel structure failures, which happened in Slovakia a few years ago. Features of cracking are illustrated on real cases of breakdowns in the transmission gas pipelines, at the cement works and in the petrochemical indus-try. All failures were caused by an incorrect technical approach. Possible remedial measures are proposed.

  20. An Exciting Time for Steel City

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Panzhihua, in south Sichuan’s basin, is aptly called West China’s Industrial Pearl, and "treasure bowl." This city is well known as the home of Panzhihua Iron and Steel Group Company and Ertan Hydropower Station. At the beginning of 2004, two major events thrust this city into the limelight.