WorldWideScience

Sample records for a537 carbon steel

  1. POTENTIAL FOR STRESS CORROSION CRACKING OF A537 CARBON STEEL NUCLEAR WASTE TANKS CONTAINING HIGHLY CAUSTIC SOLUTIONS

    Lam, P.; Stripling, C.; Fisher, D.; Elder, J.

    2010-04-26

    The evaporator recycle streams of nuclear waste tanks may contain waste in a chemistry and temperature regime that exceeds the current corrosion control program, which imposes temperature limits to mitigate caustic stress corrosion cracking (CSCC). A review of the recent service history found that two of these A537 carbon steel tanks were operated in highly concentrated hydroxide solution at high temperature. Visual inspections, experimental testing, and a review of the tank service history have shown that CSCC has occurred in uncooled/un-stress relieved tanks of similar construction. Therefore, it appears that the efficacy of stress relief of welding residual stress is the primary corrosion-limiting mechanism. The objective of this experimental program is to test A537 carbon steel small scale welded U-bend specimens and large welded plates (30.48 x 30.38 x 2.54 cm) in a caustic solution with upper bound chemistry (12 M hydroxide and 1 M each of nitrate, nitrite, and aluminate) and temperature (125 C). These conditions simulate worst-case situations in these nuclear waste tanks. Both as-welded and stress-relieved specimens have been tested. No evidence of stress corrosion cracking was found in the U-bend specimens after 21 days of testing. The large plate test was completed after 12 weeks of immersion in a similar solution at 125 C except that the aluminate concentration was reduced to 0.3 M. Visual inspection of the plate revealed that stress corrosion cracking had not initiated from the machined crack tips in the weld or in the heat affected zone. NDE ultrasonic testing also confirmed subsurface cracking did not occur. Based on these results, it can be concluded that the environmental condition of these tests was unable to develop stress corrosion cracking within the test periods for the small welded U-bends and for the large plates, which were welded with an identical procedure as used in the construction of the actual nuclear waste tanks in the 1960s. The

  2. INVESTIGATION OF THE POTENTIAL FOR CAUSTIC STRESS CORROSION CRACKING OF A537 CARBON STEEL NUCLEAR WASTE TANKS

    Lam, P.

    2009-10-15

    The evaporator recycle streams contain waste in a chemistry and temperature regime that may be outside of the current waste tank corrosion control program, which imposes temperature limits to mitigate caustic stress corrosion cracking (CSCC). A review of the recent service history (1998-2008) of Tanks 30 and 32 showed that these tanks were operated in highly concentrated hydroxide solution at high temperature. Visual inspections, experimental testing, and a review of the tank service history have shown that CSCC has occurred in uncooled/un-stress relieved F-Area tanks. Therefore, for the Type III/IIIA waste tanks the efficacy of the stress relief of welding residual stress is the only corrosion-limiting mechanism. The objective of this experimental program is to test carbon steel small scale welded U-bend specimens and large welded plates (12 x 12 x 1 in.) in a caustic solution with upper bound chemistry (12 M hydroxide and 1 M each of nitrate, nitrite, and aluminate) and temperature (125 C). These conditions simulate worst-case situations in Tanks 30 and 32. Both as-welded and stress-relieved specimens have been tested. No evidence of stress corrosion cracking was found in the U-bend specimens after 21 days of testing. The large plate test is currently in progress, but no cracking has been observed after 9 weeks of immersion. Based on the preliminary results, it appears that the environmental conditions of the tests are unable to develop stress corrosion cracking within the duration of these tests.

  3. Corrosion of a carbon steel in simulated liquid nuclear wastes

    This work is part of a collaboration agreement between CNEA (National Atomic Energy Commission of Argentina) and USDOE (Department of Energy of the United States of America), entitled 'Tank Corrosion Chemistry Cooperation', to study the corrosion behavior of carbon steel A537 class 1 in different simulated non-radioactive wastes in order to establish the safety concentration limits of the tank waste chemistry at Hanford site (Richland-US). Liquid high level nuclear wastes are stored in tanks made of carbon steel A537 (ASTM nomenclature) that were designed for a service life of 20 to 50 years. A thickness reduction of some tank walls, due to corrosion processes, was detected at Hanford site, beyond the existing predicted values. Two year long-term immersion tests were started using non radioactive simulated liquid nuclear waste solutions at 40 C degrees. This work extends throughout the first year of immersion. The simulated solutions consist basically in combinations of the 10 most corrosion significant chemical components: 5 main components (NaNO3, NaCl, NaF, NaNO2 and NaOH) at three concentration levels and 5 secondary components at two concentration levels. Measurements of the general corrosion rate with time were performed for carbon steel coupons, both immersed in the solutions and in the vapor phases, using weight loss and electrochemistry impedance spectroscopy techniques. Optic and scanning electron microscopy examination, analysis of U-bend samples and corrosion potential measurements, were also done. Localized corrosion susceptibility (pitting and crevice corrosion) was assessed in isolated short-term tests by means of cyclic potentiodynamic polarization curves. The effect of the simulated waste composition on the corrosion behavior of A537 steel was studied based on statistical analyses. The Surface Response Model could be successfully applied to the statistical analysis of the A537 steel corrosion in the studied solutions. General corrosion was not

  4. Ultrahigh carbon steels, Damascus steels, and superplasticity

    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.

  5. Metalurgia de uniones soldadas de aceros disímiles (astm a240-a537) y comportamiento mecánico ante cargas monotónica y cíclica Metallurgy of dissimilar steels welded unions (astm a240-a537) and mechanical behavior under monotonic and cyclic loads

    Andrés García; Rafael Salas; Leiry Centeno; Alberto Velázquez del Rosario

    2012-01-01

    En el presente estudio se caracterizaron las propiedades mecánicas en uniones soldadas de aceros disímiles: un acero estructural (ASTM A537/A537M:95) soldado a tope con un acero inoxidable austenítico 304L (ASTM A240/A240M:01) mediante proceso por arco eléctrico con protección inerte de gas argón (GMAW) y un acero inoxidable austenítico ER- 308L como material aporte (ANSI/AWS A5.9/A5.9M:2006). Las muestras se ensayaron en condición sin soldadura, con el objeto de caracterizar los materiales i...

  6. History of ultrahigh carbon steels

    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.

  7. Corrosion of carbon steel welds

    This report assesses the factors which cause preferential attack to occur in carbon steel fusion welds. It was concluded that the main factors were: the inclusion content of the weld metal, the potential of the weld metal being less noble than that of the parent, and the presence of low-temperature transformation products in the heat-affected zone of the weld. These factors should be minimized or eliminated as appropriate so that the corrosion allowances determined for carbon steel waste drums is also adequate for the welds. An experimental/theoretical approach is recommended to evaluate the relative corrosion resistance of welds prepared from BS 4360 grade 43A steel to that of the parent material. (author)

  8. Carbon Segregation of Bearing Steel Concasting Billet

    2000-01-01

    The formation mechanism of “white band” and central carbon segregation of high-carbon Cr bearing steel concasting billets are discussed in this paper. The maximum oxygen content in the steel produced by concasting process was 13x10-6 with an average oxygen content of 9.3x 10-6.Comparison of metallurgical quality and fatigue property between the concasting steel (CC) andingot casting steel (IC) showed that the carbon segregation (C/C0) in former steel was 0.92~1.10and its fatigue life was equal to that of the latter steel.

  9. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    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...

  10. Plain carbon steel bipolar plates for PEMFC

    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.

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

    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.

  12. Welding of high manganese- and carbon steels

    Technology and conditions of welding of high manganese and carbon steel by a resistance welding technique using an intermediate part are developed. Austenitic chromium-nickel 12Kh18N10T steel is chosen as a material of the intermediate part. The recommended welding conditions insure a high quality of the weld joint in terms of metal structure and its mechanical properties. It is the basic metal of the joint that fractures under mechanical testing

  13. Marine atmospheric corrosion of carbon steels

    Morcillo, Manuel; Alcántara, Jenifer; Díaz, Iván; Chico, Belén; Simancas, Joaquín; de la Fuente, Daniel

    2015-01-01

    Basic research on marine atmospheric corrosion of carbon steels is a relatively young scientific field and there continue to be great gaps in this area of knowledge. The presence of akaganeite in the corrosion products that form on steel when it is exposed to marine atmospheres leads to a notable increase in the corrosion rate. This work addresses the following issues: (a) environmental conditions necessary for akaganeite formation; (b) characterisation of akaganeite in the corrosion products...

  14. Deformation and Recrystallisation in Low Carbon Steels

    Almojil, Marwan

    2010-01-01

    The annealing behaviour, including studies of recrystallisation kinetics anddevelopment of crystallographic texture, of two low carbon steels after different coldrolling reductions have been investigated using Optical Microscopy (OM), ElectronBack-Scatter Diffraction (EBSD) and Transmission Electron Microscopy (TEM).The primary recrystallisation behaviour of 20, 50, 70 and 90% cold rolled InterstitialFree (IF) and High Strength Low Alloy (HSLA) steels was studied. The HSLA wasinitially proces...

  15. Tests Of Protective Coats For Carbon Steel

    Macdowell, Louis G., III

    1995-01-01

    Report describes laboratory and field tests of candidate paints (primers, tie coats, and topcoats) for use in protecting carbon-steel structures against corrosion in seaside environment at Kennedy Space Center. Coating materials selected because of utility in preventing corrosion, also on basis of legal requirements, imposed in several urban areas, for reduction of volatile organic contents.

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

    2001-01-01

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

  17. Microbially induced corrosion of carbon steel in deep groundwater environment

    Rajala, Pauliina; Carpén, Leena; Vepsäläinen, Mikko; Raulio, Mari; Sohlberg, Elina; Bomberg, Malin

    2015-01-01

    The metallic low and intermediate level radioactive waste generally consists of carbon steel and stainless steels. The corrosion rate of carbon steel in deep groundwater is typically low, unless the water is very acidic or microbial activity in the environment is high. Therefore, the assessment of microbially induced corrosion of carbon steel in deep bedrock environment has become important for evaluating the safety of disposal of radioactive waste. Here we studied the corrosion inducing abil...

  18. EIS Response of MIC on Carbon Steel

    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...... identifying the formation of biofilm/ferrous sulphide layers but unfortunately also that corrosion rate estimation by these electrochemical techniques is unreliable when these layers form. These considerations are also relevant for other corrosion systems where film formation might mask the electrochemical...

  19. Microbially induced corrosion of carbon steel in deep groundwater environment

    Rajala, Pauliina; Carpén, Leena; Vepsäläinen, Mikko; Raulio, Mari; Sohlberg, Elina; Bomberg, Malin

    2015-01-01

    The metallic low and intermediate level radioactive waste generally consists of carbon steel and stainless steels. The corrosion rate of carbon steel in deep groundwater is typically low, unless the water is very acidic or microbial activity in the environment is high. Therefore, the assessment of microbially induced corrosion of carbon steel in deep bedrock environment has become important for evaluating the safety of disposal of radioactive waste. Here we studied the corrosion inducing ability of indigenous microbial community from a deep bedrock aquifer. Carbon steel coupons were exposed to anoxic groundwater from repository site 100 m depth (Olkiluoto, Finland) for periods of 3 and 8 months. The experiments were conducted at both in situ temperature and room temperature to investigate the response of microbial population to elevated temperature. Our results demonstrate that microorganisms from the deep bedrock aquifer benefit from carbon steel introduced to the nutrient poor anoxic deep groundwater environment. In the groundwater incubated with carbon steel the planktonic microbial community was more diverse and 100-fold more abundant compared to the environment without carbon steel. The betaproteobacteria were the most dominant bacterial class in all samples where carbon steel was present, whereas in groundwater incubated without carbon steel the microbial community had clearly less diversity. Microorganisms induced pitting corrosion and were found to cluster inside the corrosion pits. Temperature had an effect on the species composition of microbial community and also affected the corrosion deposits layer formed on the surface of carbon steel. PMID:26257707

  20. Microbially induced corrosion of carbon steel in deep groundwater environment

    Pauliina eRajala

    2015-07-01

    Full Text Available The metallic low and intermediate level radioactive waste generally consists of carbon steel and stainless steels. The corrosion rate of carbon steel in deep groundwater is typically low, unless the water is very acidic or microbial activity in the environment is high. Therefore, the assessment of microbially induced corrosion of carbon steel in deep bedrock environment has become important for evaluating the safety of disposal of radioactive waste. Here we studied the corrosion inducing ability of indigenous microbial community from a deep bedrock aquifer. Carbon steel coupons were exposed to anoxic groundwater from repository site 100 m depth (Olkiluoto, Finland for periods of three and eight months. The experiments were conducted at both in situ temperature and room temperature to investigate the response of microbial population to elevated temperature. Our results demonstrate that microorganisms from the deep bedrock aquifer benefit from carbon steel introduced to the nutrient poor anoxic deep groundwater environment. In the groundwater incubated with carbon steel the planktonic microbial community was more diverse and 100-fold more abundant compared to the environment without carbon steel. The betaproteobacteria were the most dominant bacterial class in all samples where carbon steel was present, whereas in groundwater incubated without carbon steel the microbial community had clearly less diversity. Microorganisms induced pitting corrosion and were found to cluster inside the corrosion pits. Temperature had an effect on the species composition of microbial community and also affected the corrosion deposits layer formed on the surface of carbon steel.

  1. Microbially induced corrosion of carbon steel in deep groundwater environment.

    Rajala, Pauliina; Carpén, Leena; Vepsäläinen, Mikko; Raulio, Mari; Sohlberg, Elina; Bomberg, Malin

    2015-01-01

    The metallic low and intermediate level radioactive waste generally consists of carbon steel and stainless steels. The corrosion rate of carbon steel in deep groundwater is typically low, unless the water is very acidic or microbial activity in the environment is high. Therefore, the assessment of microbially induced corrosion of carbon steel in deep bedrock environment has become important for evaluating the safety of disposal of radioactive waste. Here we studied the corrosion inducing ability of indigenous microbial community from a deep bedrock aquifer. Carbon steel coupons were exposed to anoxic groundwater from repository site 100 m depth (Olkiluoto, Finland) for periods of 3 and 8 months. The experiments were conducted at both in situ temperature and room temperature to investigate the response of microbial population to elevated temperature. Our results demonstrate that microorganisms from the deep bedrock aquifer benefit from carbon steel introduced to the nutrient poor anoxic deep groundwater environment. In the groundwater incubated with carbon steel the planktonic microbial community was more diverse and 100-fold more abundant compared to the environment without carbon steel. The betaproteobacteria were the most dominant bacterial class in all samples where carbon steel was present, whereas in groundwater incubated without carbon steel the microbial community had clearly less diversity. Microorganisms induced pitting corrosion and were found to cluster inside the corrosion pits. Temperature had an effect on the species composition of microbial community and also affected the corrosion deposits layer formed on the surface of carbon steel. PMID:26257707

  2. Integrating Steel Production with Mineral Carbon Sequestration

    Klaus Lackner; Paul Doby; Tuncel Yegulalp; Samuel Krevor; Christopher Graves

    2008-05-01

    The objectives of the project were (i) to develop a combination iron oxide production and carbon sequestration plant that will use serpentine ores as the source of iron and the extraction tailings as the storage element for CO2 disposal, (ii) the identification of locations within the US where this process may be implemented and (iii) to create a standardized process to characterize the serpentine deposits in terms of carbon disposal capacity and iron and steel production capacity. The first objective was not accomplished. The research failed to identify a technique to accelerate direct aqueous mineral carbonation, the limiting step in the integration of steel production and carbon sequestration. Objective (ii) was accomplished. It was found that the sequestration potential of the ultramafic resource surfaces in the US and Puerto Rico is approximately 4,647 Gt of CO2 or over 500 years of current US production of CO2. Lastly, a computer model was developed to investigate the impact of various system parameters (recoveries and efficiencies and capacities of different system components) and serpentinite quality as well as incorporation of CO2 from sources outside the steel industry.

  3. Low carbon manganese-nickel-niobium steel

    Experimental heats of a low carbon-manganese-0.5% nickel-0.15% niobium steel have been rolled to plates between 13.5 and 50 mm thickness and to a 16 mm hot strip. Various combinations of soaking temperatures form 11000C to 13000C and of finish rolling temperatures between 7100C and 9300C have been investigated. From mechanical properties obtained, one can conclude that the investigated steel composition provides very good properties e.g. for pipe steels X65 to X75. In particular, the toughness at low temperature is outstanding despite relaxed rolling conditions. Metalographic and special investigations such as electron microscopy, texture evaluation and chemical extraction, correlated with applied rolling schedules and the mechanical properties obtained resulted in a comprehensive understanding about the benefits of high niobium metallurgy combined with nickel addition. All practically applied welding processes generated mechanical properties, in particular toughness of the weldment, that meet arctic specifications.(Author)

  4. Marine atmospheric corrosion of carbon steels

    Basic research on marine atmospheric corrosion of carbon steels is a relatively young scientific field and there continue to be great gaps in this area of knowledge. The presence of akaganeite in the corrosion products that form on steel when it is exposed to marine atmospheres leads to a notable increase in the corrosion rate. This work addresses the following issues: (a) environmental conditions necessary for akaganeite formation; (b) characterisation of akaganeite in the corrosion products formed; (c) corrosion mechanisms of carbon steel in marine atmospheres; (d) exfoliation of rust layers formed in highly aggressive marine atmospheres; (e) long-term corrosion rate prediction; and (f) behaviour of weathering steels. Field research has been carried out at Cabo Vilano wind farm (Camarinas, Galicia) in a wide range of atmospheric salinities and laboratory work involving the use of conventional atmospheric corrosion techniques and near-surface and bulk sensitive analytical techniques: scanning electron microscopy (SEM)/energy dispersive spectrometry (EDS), X-ray diffraction (XRD), Mossbauer spectroscopy and SEM/μRaman spectroscopy. (Author)

  5. Marine atmospheric corrosion of carbon steels

    Morcillo, M.; Alcantara, J.; Diaz, I.; Chico, B.; Simancas, J.; Fuente, D. de la

    2015-07-01

    Basic research on marine atmospheric corrosion of carbon steels is a relatively young scientific field and there continue to be great gaps in this area of knowledge. The presence of akaganeite in the corrosion products that form on steel when it is exposed to marine atmospheres leads to a notable increase in the corrosion rate. This work addresses the following issues: (a) environmental conditions necessary for akaganeite formation; (b) characterisation of akaganeite in the corrosion products formed; (c) corrosion mechanisms of carbon steel in marine atmospheres; (d) exfoliation of rust layers formed in highly aggressive marine atmospheres; (e) long-term corrosion rate prediction; and (f) behaviour of weathering steels. Field research has been carried out at Cabo Vilano wind farm (Camarinas, Galicia) in a wide range of atmospheric salinities and laboratory work involving the use of conventional atmospheric corrosion techniques and near-surface and bulk sensitive analytical techniques: scanning electron microscopy (SEM)/energy dispersive spectrometry (EDS), X-ray diffraction (XRD), Mossbauer spectroscopy and SEM/μRaman spectroscopy. (Author)

  6. Nanostructure-based Processes at the Carbonizing Steels

    L.I. Roslyakova

    2015-12-01

    Full Text Available The studies of nanostructure-based processes carburizing steels showed that oxidizing atmosphere when carburizing steel contains along with carbon dioxide (CO2 + C = 2CO molecular and atmospheric oxygen (O2 + 2C = 2CO; O + C = CO released from the carbonate ВаСОз during its thermal dissociation. Intensive formation of CO provides high carbonizing ability of carbonate-soot coating and steel.

  7. Internal friction in martensitic carbon steels

    Hoyos, J.J., E-mail: jjhoyos@unal.edu.co [Grupo de Ciencia y Tecnologia de los Materiales, Universidad Nacional de Colombia, Sede Medellin, Carrera 80 Numero 65-223, Medellin (Colombia); Ghilarducci, A.A., E-mail: friccion@cab.cnea.gov.ar [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, Instituto Balseiro-Universidad Nacional de Cuyo, Consejo Nacional de Investigaciones Cientificas y Tecnologicas, Av. Bustillo 9500, 8400 Bariloche RN (Argentina); Salva, H.R., E-mail: salva@cab.cnea.gov.ar [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, Instituto Balseiro-Universidad Nacional de Cuyo, Consejo Nacional de Investigaciones Cientificas y Tecnologicas, Av. Bustillo 9500, 8400 Bariloche RN (Argentina); Chaves, C.A., E-mail: cachaves@unal.edu.co [Grupo de Ciencia y Tecnologia de los Materiales, Universidad Nacional de Colombia, Sede Medellin, Carrera 80 Numero 65-223, Medellin (Colombia); Velez, J.M., E-mail: jmvelez@unal.edu.co [Grupo de Ciencia y Tecnologia de los Materiales, Universidad Nacional de Colombia, Sede Medellin, Carrera 80 Numero 65-223, Medellin (Colombia)

    2009-09-15

    This paper proposes relationships between the internal friction and the microstructure of two steels containing 0.626 and 0.71 wt.% carbon. The steels were annealed at 1093 K for 5 min, quenched into water and tempered for 10 min at 423, 573 and 723 K. Internal friction was measured by using a forced vibration pendulum, in a temperature range from 100 to 450 K. The internal friction spectrum is decomposed into four peaks: P1 at 215 K, P2 at 235 K, P3 at 260 K and P4 at 380 K for 3 Hz. Peak P1 is attributed to the interactions between dislocations and carbon atoms. Peak P2 is related to the interaction between dislocations and carbide. Peak P3 is related to the generations of kink - pairs along edge dislocations. Peak P4 is attributed to epsilon carbide precipitation.

  8. Ultrahigh carbon steel for automotive applications

    Lesuer, D.R.; Syn, C.K. [Lawrence Livermore National Lab., CA (United States); Sherby, O.D. [Stanford Univ., CA (United States)

    1995-12-04

    Ultrahigh carbon steels (UHCSs), which contain 1--2.1% carbon, have remarkable structural properties for automotive application when processed to achieve fine ferrite grains with fine spheroidized carbides. When processed for high room temperature ductility, UHCS can have good tensile ductility but significantly higher strength than current automotive high strength steels. The material can also be made superplastic at intermediate temperatures and exhibits excellent die fill capability. Furthermore, they can be made hard with high compression ductility. In wire form it is projected that UHCS can exhibit extremely high strengths (5,000 MPa) for tire cord applications. Examples of structural components that have been formed from fine-grained spheroidized UHCSs are illustrated.

  9. Internal friction in martensitic carbon steels

    This paper proposes relationships between the internal friction and the microstructure of two steels containing 0.626 and 0.71 wt.% carbon. The steels were annealed at 1093 K for 5 min, quenched into water and tempered for 10 min at 423, 573 and 723 K. Internal friction was measured by using a forced vibration pendulum, in a temperature range from 100 to 450 K. The internal friction spectrum is decomposed into four peaks: P1 at 215 K, P2 at 235 K, P3 at 260 K and P4 at 380 K for 3 Hz. Peak P1 is attributed to the interactions between dislocations and carbon atoms. Peak P2 is related to the interaction between dislocations and carbide. Peak P3 is related to the generations of kink - pairs along edge dislocations. Peak P4 is attributed to epsilon carbide precipitation.

  10. Hydrogen Effects on Austenitic Stainless Steels and High-Strength Carbon Steels

    Todoshchenko, Olga

    2015-01-01

    The resistance to hydrogen embrittlement is an important factor in the development of new steel grades for a variety of applications. The thesis describes investigations on hydrogen effects on two classes of steels - austenitic stainless steels and advanced high-strength carbon steels. Hydrogen solubility and diffusion in metastable austenitic stainless steels are studied with thermal desorption spectroscopy (TDS). This method, together with the mathematical modeling of the processes of hy...

  11. Friction stir processing on carbon steel

    Tarasov, Sergei Yu., E-mail: tsy@ispms.ru [Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055, Russia and National Research Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation); Melnikov, Alexander G., E-mail: melnikov-ag@tpu.ru [National Research Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation); Rubtsov, Valery E., E-mail: rvy@ispms.ru [Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055 (Russian Federation)

    2014-11-14

    Friction stir processing of medium carbon steel samples has been carried out using a milling machine and tools made of cemented tungsten carbide. Samples have been machined from 40 and 40X steels. The tools have been made in the shape of 5×5×1.5 mm and 3×3×1.5 mm tetrahedrons. The microstructure of stirred zone has been obtained using the smaller tool and consists of fine recrystallized 2-3 μm grains, whereas the larger tool has produced the 'onion-like' structures comprising hard quenched 'white' 500-600 MPa layers with 300-350 MPa interlayers of bainite needles. The mean values of wear intensity obtained after measuring the wear scar width were 0.02 mm/m and 0.001 mm/m for non-processed and processed samples, respectively.

  12. Friction stir processing on carbon steel

    Friction stir processing of medium carbon steel samples has been carried out using a milling machine and tools made of cemented tungsten carbide. Samples have been machined from 40 and 40X steels. The tools have been made in the shape of 5×5×1.5 mm and 3×3×1.5 mm tetrahedrons. The microstructure of stirred zone has been obtained using the smaller tool and consists of fine recrystallized 2-3 μm grains, whereas the larger tool has produced the 'onion-like' structures comprising hard quenched 'white' 500-600 MPa layers with 300-350 MPa interlayers of bainite needles. The mean values of wear intensity obtained after measuring the wear scar width were 0.02 mm/m and 0.001 mm/m for non-processed and processed samples, respectively

  13. 76 FR 15299 - Certain Hot-Rolled Carbon Steel Flat Products From India: Preliminary Rescission of...

    2011-03-21

    ...), or both, added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels with...) steels, and the substrate for motor lamination steels. IF steels are recognized as low carbon steels with... FR 74682 (December 1, 2010). On January 3, 2011, we received from United States Steel Corporation,...

  14. Test Of Protective Coatings On Carbon Steel

    Macdowell, Louis

    1993-01-01

    Report describes results of tests in which carbon-steel panels coated with one-or two-component solvent-based inorganic zinc primers and top-coated with inorganic topcoat or any of various organic topcoats, placed on outdoor racks at beach at Kennedy Space Center for 5 years. From time to time, slurry of Al(2)O(3) in 10-percent HCI solution applied to some of panels to simulate corrosive effect of effluent from solid-fuel rocket booster engines. Panels coated with inorganic topcoat performed much better than organic-topcoated panels.

  15. Passivation of carbon steel through mercury implantation

    Wilbur, P. J.; Robinson, R. S.

    1981-01-01

    An experiment, in which carbon steel samples were implanted with mercury ions from a broad beam ion source and their corrosion characteristics in air were evaluated, is described. Mercury doses of a few mA min/square cm at energies of a few hundred electron volts are shown to effect significant improvements in the corrosion resistance of the treated surfaces. In a warm moist environment the onset of rusting was extended from 15 min. for an untreated sample to approximately 30 hrs. for one implanted at a dose of 33 mA min/square cm with 1000 eV mercury ions.

  16. Microbially influenced corrosion of carbon steels

    White, D.C.; Jack, R.F.; Dowling, N.J.E.; Franklin, M.J.; Nivens, D.E.; Brooks, S.; Mittelman, M.W.; Vass, A.A. (Tennessee Univ., Knoxville, TN (USA). Inst. for Applied Microbiology); Isaacs, H.S. (Brookhaven National Lab., Upton, NY (USA))

    1990-01-01

    Microbially influenced corrosion of pipeline steels is an economically important problem. Microbes form tubercles which block fluid flow and can facilitate localized corrosion leading to through-wall penetrations. Microbes of diverse physiological types and metabolic potentialities have been recovered from fresh tubercles or under-deposit corrosion and have been characterized. In tests utilizing sterilizable flow-through systems containing pipeline steel coupons, corrosion rates determined by nondestructive electrochemical means have indicated that increasing the number of physiological types of microbes inoculated into the system generally increased the severity of the microbially influenced corrosion (MIC). This study reports the MIC of monocultures and combinations of monocultures in an aerobic fresh water system with low sulfate and an anaerobic saline system. In both the aerobic and anaerobic systems, the combination of microbes induced greater MIC responses than the monocultures. In tests involving a combination of microbes in both systems in which one member was a sulfate-reducing bacteria (SRB), the corrosion mechanism was different for the control and the monocultures. This difference was indicated by the phase shift in the electrochemical impedance spectra (EIS). The localization of corrosion, that in many cases is the hallmark of MIC, may be initiated by the inhomogeneities of supposedly smooth metal surfaces. The scanning vibrating electrode technique (SVET) demonstrated non-uniform current densities over carbon steel electrodes polished to a 600 grit finish suggesting pitting and repassivation of pits in sterile medium.

  17. Corrosion rate of carbon steel in NS tank water

    Neutron shield tank (NST) is an open tank 12.5 meters in height and 12 meters dia constructed around the research reactor. It is filled with water to (i) provide shielding from the neutron radiation, (ii) to remove the heat from the Pressure suppression system during LOCA and (iii) to act as a heat sink. NST is made of IS2062 carbon steel and it contains the stainless steel tanks, CS support structures, forged carbon steel gas cylinders, steel containment and its supports and emergency cooling down system condensers made of ASTM 350 grade LF2 carbon steel. All the equipments/systems located inside NST are painted with epoxy paint. NST is filled up 12 meters ie with 1200 m3 of water. The water chemistry parameters and microbiological parameters and corrosion rate of carbon steel materials in NST water at various water chemistry and various depths are discussed in the paper. (author)

  18. Thermoplastic liners for carbon steel pipelines

    Mehdi, Mauyed S.; AlDossary, Abdullah K. [Saudi Aramco, Dhahran (Saudi Arabia)

    2009-12-19

    Materials selection for pipe and fittings used to convey corrosive fluids has often been a challenge. Traditionally, exotic Corrosion Resistant Alloys (CRA) have been used in corrosive environments despite their high cost. Plastic lined carbon steel piping offers a cost effective alternative to the use of CRAs by eliminating corrosion, significantly reducing the use of toxic chemicals and the heavy metal usually present in CRAs. Thermoplastic Liners offer the combination of corrosion resistance and mechanical strength, which are unachievable with singular materials. Under pressure conditions, the liner is fully supported by the metalwork, while under vacuum conditions, the liner must be thick enough along with venting system to withstand the collapsing forces created by the negative pressure. Plastic liners have been used successfully to line and protect metallic pipelines for many years and have become an indispensable requirement of the oil and gas industry particularly with water injection and hydrocarbon services. In the case of internally corroded pipes, the use of thermoplastic liners for rehabilitation is an option to extend the lifetime of companies' assets, reduce maintenance cost and increase intervals between T and Is. For new construction, plastic liners in carbon steel pipes can compete technically and economically with pipelines of CRA materials and other corrosion inhibition systems. This paper describes various design features, installations of thermoplastic liners in comparison to other corrosion inhibition methods. (author)

  19. Basic studies on carbon steel decontamination

    The dissolution of magnetite films grown in autoclave at high temperature on carbon steel has been performed in a dynamic loop in ammoniated citric and oxalic acid solutions at two different temperatures and constant pH. The dissolution process seems to be affected by the dual-layer oxide morphology depending on the growth conditions in the autoclave. The open-circuit potential of the specimens and the corrosion rate measured by the linear polarization method have been monitored. To this aim a particular corrosion cell and a suitable reference electrode have been set up at CISE. Polarization curves have been performed to check the electrochemical processes involved in the anodic and cathodic area. At last the effect of a corrosion inhibitor, of a complexing and a reducing agent and of temperature has also been studied. The work was carried out in the frame of a CNEN research programme for the development of the CIRENE prototype

  20. Strength enhancement possibilities of low carbon steels

    M. Greger

    2006-08-01

    Full Text Available Purpose: The paper analyses methods of grain refinement and demonstrates development of structure andproperties of metallic materials after severe plastic deformations (SPD.Design/methodology/approach: Technology ARB was experimentally verified. The material was rolled in 11passes. Rolling proceeded at temperature 650˚C, with heating in furnace with inert atmosphere (Ar.Findings: True strain has achieved the value 9. Basic relations between magnitude of deformation, grainrefinement and resulting mechanical properties were described. Bonding of degree was greater than 90%.Practical implications: ARB method is one of instrument for acquirement materials with ultrafine grainstructure. Is it very simply apparatus, which can be used in practical technology (classical rolling mill.Originality/value: Development of structure was verified on low carbon steel. Obtained grain size was around 0.3 μm.Properties obtained by tensile test did not achieve the expected value. Grain size was homogenous in whole volume.

  1. 75 FR 32911 - Preliminary Results of Antidumping Duty Administrative Review: Circular Welded Carbon Steel Pipes...

    2010-06-10

    ... Welded Carbon Steel Pipes and Tubes From Taiwan AGENCY: Import Administration, International Trade... administrative review of the antidumping duty order on circular welded carbon steel pipes and tubes from Taiwan... circular welded carbon steel pipes and tubes from Taiwan. See Certain Circular Welded Carbon Steel...

  2. 76 FR 33210 - Preliminary Results of Antidumping Duty Administrative Review: Circular Welded Carbon Steel Pipes...

    2011-06-08

    ... Welded Carbon Steel Pipes and Tubes From Taiwan AGENCY: Import Administration, International Trade... administrative review of the antidumping duty order on circular welded carbon steel pipes and tubes from Taiwan... circular welded carbon steel pipes and tubes from Taiwan. See Certain Circular Welded Carbon Steel...

  3. Marine atmospheric corrosion of carbon steels

    Morcillo, Manuel

    2015-06-01

    Full Text Available Basic research on marine atmospheric corrosion of carbon steels is a relatively young scientific field and there continue to be great gaps in this area of knowledge. The presence of akaganeite in the corrosion products that form on steel when it is exposed to marine atmospheres leads to a notable increase in the corrosion rate. This work addresses the following issues: (a environmental conditions necessary for akaganeite formation; (b characterisation of akaganeite in the corrosion products formed; (c corrosion mechanisms of carbon steel in marine atmospheres; (d exfoliation of rust layers formed in highly aggressive marine atmospheres; (e long-term corrosion rate prediction; and (f behaviour of weathering steels. Field research has been carried out at Cabo Vilano wind farm (Camariñas, Galicia in a wide range of atmospheric salinities and laboratory work involving the use of conventional atmospheric corrosion techniques and near-surface and bulk sensitive analytical techniques: scanning electron microscopy (SEM/energy dispersive spectrometry (EDS, X-ray diffraction (XRD, Mössbauer spectroscopy and SEM/μRaman spectroscopy.La investigación fundamental en corrosión atmosférica marina de aceros al carbono es un campo científico relativamente joven que presenta grandes lagunas de conocimiento. La formación de akaganeíta en los productos de corrosión que se forman sobre el acero cuando se expone a atmósferas marinas conduce a un incremento notable de la velocidad de corrosión. En el trabajo se abordan las siguientes cuestiones: (a condiciones ambientales necesarias para la formación de akaganeíta, (b caracterización de la akaganeíta en los productos de corrosión formados, (c mecanismos de corrosión del acero al carbono en atmósferas marinas, (d exfoliación de las capas de herrumbre formadas en atmósferas marinas muy agresivas, (e predicción de la velocidad de corrosión a largo plazo, y (f comportamiento de aceros patinables. La

  4. Comparison of Impact Properties for Carbon and Low Alloy Steels

    O.H. Ibrahim

    2011-01-01

    The impact properties of hot rolled carbon steel (used for the manufacture of reinforcement steel bars) and the quenched & tempered (Q&T) low alloy steel (used in the pressure vessel industry) were determined. The microstructure of the hot rolled carbon steel contained ferrite/pearlite phases, while that of the quenched and tempered low alloy steel contained bainite structure. Impact properties were determined for both steels by instrumented impact testing at temperatures between -150 and 200℃. The impact properties comprised total impact energy, ductile to brittle transition temperature, crack initiation and propagation energy, brittleness transition temperature and cleavage fracture stress. The Q&T low alloy steel displayed much higher resistance to ductile fracture at high test temperatures, while its resistance to brittle fracture at low test temperatures was a little higher than that of the hot rolled carbon steel. The results were discussed in relation to the difference in the chemical composition and microstructure for the two steels.

  5. Tests Of Materials For Repair Coating Of Carbon Steel

    Macdowell, Louis G., III

    1995-01-01

    Report describes tests of paints (primers and topcoats) for use in recoating rusted carbon steel for protection against further corrosion. Paints selected for evaluation all designated by manufacturers as suitable for application over tightly adhering rust.

  6. Warm Deformation Microstructure of a Plain Carbon Steel

    B Eghbali; M Shaban

    2011-01-01

    Grain refinement in a plain carbon steel under intercritical warm deformation was studied by torsion tes ring. Based on the experimental results, the warm flow behaviour and microstructural evolution of ferrite were researched with particular emphasis on

  7. Investigation of boron segregation in low carbon steel

    J. Lis; Lis, A; Kolan, C.

    2011-01-01

    Traces of born in the range 0,002-0,009 % are usually added to many grades of steel. The effect of boron on phase transformations and hardenability of low carbon low alloy steels depends on the form of its behavior in solid solution either in segregations or in precipitations. Temperature and cooling rate determine the existence of boron segregations on grain boundaries. In present paper simulations of boron concentrations were calculated with computer programme DICTRA for low carbon 0,08 %C ...

  8. 76 FR 2344 - Certain Hot-Rolled Carbon Steel Flat Products From India: Notice of Preliminary Results of...

    2011-01-13

    ... columbium), or both, added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels...'') steels, and the substrate for motor lamination steels. IF steels are recognized as low- carbon steels... Antidumping Duty Order: Certain Hot-Rolled Carbon Steel Flat Products From India, 66 FR 60194 (December...

  9. 76 FR 48143 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Preliminary...

    2011-08-08

    ...), or both, added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels with...'') steels, and the substrate for motor lamination steels. IF steels are recognized as low carbon steels with...: Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China, 66 FR 59561...

  10. Trial manufacturing of copper-carbon steel composite overpack

    This paper reports the results of design analysis and trial manufacturing of copper-carbon steel composite overpacks. The overpack is one of the key components of the engineered barrier system, hence, it is necessary to confirm the applicability of current technique in their manufacture. The copper-carbon steel composite overpack consists of a double container, an outer vessel made of oxygen-free, high-purity copper as the corrosion allowance material, and an inner vessel made of carbon steel as the pressure-resistant material. The trial manufacturing in this time, only the copper outer vessel has been fabricated. Both oxygen-free copper and oxygen-free phosphorus copper were used as materials for the outer vessel. For the shell and bottom portion, these materials were formed integrally by a backward extrusion method. For sealing the top cover plate to the main body, an electron-beam welding method was applied. After manufacturing, mechanical testing of specimens from the copper vessels were carried out. It was confirmed that current technique has sufficient feasibility to manufacture outer vessel. In addition, potential for irradiation embrittlement of the inner carbon-steel vessel by irradiation from vitrified waste over the life time of the overpack has been analyzed. It was shown that the small degree of irradiation embrittlement gives no significant impact on the pressure resistance of the carbon-steel vessel. Future research and development items regarding copper-carbon steel composite overpacks are also discussed. (author)

  11. Characterization of D2 tool steel friction surfaced coatings over low carbon steel

    Highlights: • Solid state coating by friction surfacing method. • D2 tool steel is coated over relatively softer low carbon steel. • Defect free interface between tool steel coating and low carbon steel substrate. • D2 coatings exhibited higher hardness and good wear resistance. • Highly refined martensitic microstructure in the coating. - Abstract: In this work D2 tool steel coating is produced over a low carbon steel substrate using friction surfacing process. The process parameters are optimized to get a defect free coating. Microstructural characterization is carried out using optical microscopy, scanning electron microscopy and X-ray diffraction. Infrared thermography is used to measure the thermal profile during friction surfacing of D2 steel. Wear performance of the coating is studied using Pin-on-Disk wear tests. A lower rotational speed of the consumable rod and higher translational speed of the substrate is found to result in thinner coatings. Friction surfaced D2 steel coating showed fine-grained martensitic microstructure compared to the as-received consumable rod which showed predominantly ferrite microstructure. Refinement of carbides in the coating is observed due to the stirring action of the process. The infrared thermography studies showed the peak temperature attained by the D2 coating to be about 1200 °C. The combined effect of martensitic microstructure and refined carbides resulted in higher hardness and wear resistance of the coating

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

    Highlights: • The morphology of the corrosion of steel in cement paste was studied in situ. • During galvanostatic corrosion, carbon steel reinforcement corroded homogeneously. • On ferritic stainless steel, deep corrosion pits formed and caused wider cracks. • The measured rate of steel loss correlated well with Faraday’s law of electrolysis. - Abstract: 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

  13. Constant extension rate tensile tests on 304L stainless steel in simulated hazardous low-level waste

    New waste tanks which handle hazardous low-level waste were proposed to be constructed in H-area. The candidate material for the tanks is AISI Type 304L (304L) stainless steel. Constant extension rate tensile (CERT) tests were conducted to assess the susceptibility of 304L to stress-corrosion cracking (SCC) in these waste solutions. The tests demonstrated that 304L was not susceptible to SCC in simulated wastes. Based on these tests and previous pitting corrosion studies 304L is a suitable material of construction for the new tanks. Comparison tests in the same simulants were performed on A537 carbon steel (A537), a material that is similar to material of construction for the current tanks. Stress-corrosion cracking was indicated in two of the simulants. If carbon steel tanks are utilized to handle the hazardous low-level wastes, inhibitors such as nitrite or hydroxide will be necessary to prevent corrosion

  14. Microstructural characterisation of carbon implanted austenitic stainless steel

    Low carbon (316L) austenitic stainless steel has been implanted with carbon ions with a fluence of 5 x 1017 C ions/cm2 using an ion energy of 75 keV. The effect of carbon ion implantation on the microstructure of the austenitic steel has been examined in cross-section using transmission electron microscopy (TEM) both before and after implantation, and the implantation data correlated with a computer based simulation, TRIM (Transport and Range of Ions in Matter). It has been found that the high-fluence carbon ion implantation modified the microstructure of the steel, as demonstrated by the presence of two amorphous layers separated by a layer of expanded austenite

  15. Microstructural characterisation of carbon implanted austenitic stainless steel

    Murphy, M.E. [Scientific Affairs Research Group, Stryker Orthopaedics, Raheen Business Park, Limerick (Ireland)]. E-mail: matthew.murphy@stryker.com; Insley, G.M. [Scientific Affairs Research Group, Stryker Orthopaedics, Raheen Business Park, Limerick (Ireland); Laugier, M.T. [Department of Physics, University of Limerick, Limerick (Ireland); Newcomb, S.B. [Sonsam Ltd., Glebe Laboratories, Newport, Tipperary (Ireland)

    2005-06-01

    Low carbon (316L) austenitic stainless steel has been implanted with carbon ions with a fluence of 5 x 10{sup 17} C ions/cm{sup 2} using an ion energy of 75 keV. The effect of carbon ion implantation on the microstructure of the austenitic steel has been examined in cross-section using transmission electron microscopy (TEM) both before and after implantation, and the implantation data correlated with a computer based simulation, TRIM (Transport and Range of Ions in Matter). It has been found that the high-fluence carbon ion implantation modified the microstructure of the steel, as demonstrated by the presence of two amorphous layers separated by a layer of expanded austenite.

  16. Ultra low carbon bainitic (ULCB) steels after quenching and tempering

    The mechanical and Charpy V impact strength properties of new advanced ultra low carbon bainitic (ULBC) steels after water quenching and tempering (WQT) have been investigated. Their chemical compositions are given. The nine continuous cooling transformation diagrams (CCT) of the new ULCB steel grades have been established. The CCT diagrams for ULCBNi steels containing 9% Ni - grade 10N9 and 5% Ni - grade HN5MVNb are given. The comparison between CCT diagrams of 3.5%Ni + 1.5%Cu containing steels grade HSLA 100 and HN3MCu is shown. The effect of the increase in carbon and titanium contents in the chemical composition of ULCBMn steels 04G3Ti, 06G3Ti and 09G3Ti on the kinetics of phase transformations during continuous cooling is presented by the shifting CCT diagrams. The Charpy V impact strength and brittle fracture occurence curves are shown. The effect of tempering temperature on tensile properties of WQT HN3MCu steel is shown and Charpy V impact strength curves after different tempering conditions are shown. The optimum tempering temperatures region of HN3MCu steel for high Charpy V impact toughness at law temperatures - 80oC(193 K) and -120oC(153 K) is estimated. The effect of tempering temperature on mechanical properties of HN5MVNb steel is given. The low temperature impact Charpy V toughness of HN5MVNb steel is shown. The optimum range of tempering temperature during 1 hour for high toughness of WQT HN5MVNb steel is given. HN3MCu and HN5MVNb steels after WQT have high yield strength YS≥690 MPa and high Charpy V impact toughness KV≥80 J at -100oC (173K) and KCV≥50 J/cm2 at - 120oC (153K) so they may be used for cryogenic applications

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

    Fan Li; Haibo Huang

    2006-01-01

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

  18. 48 CFR 252.225-7030 - Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate.

    2010-10-01

    ... of Carbon, Alloy, and Armor Steel Plate. 252.225-7030 Section 252.225-7030 Federal Acquisition... Acquisition of Carbon, Alloy, and Armor Steel Plate. As prescribed in 225.7011-3, use the following clause: Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate (DEC 2006) (a) Carbon, alloy, and...

  19. Identification of Relevant Work Parameters of Ladle Furnace While Melting the High Ductility Steel and High-Carbon Steel

    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.

  20. 75 FR 65453 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Flat Products From Brazil: Notice of...

    2010-10-25

    ...)) steels, high strength low alloy (HSLA) steels, and the substrate for motor lamination steels. IF steels... niobium added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels with micro...-Rolled Flat-Rolled Carbon Quality Steel Products From Brazil, 64 FR 38756, 38759 (July 19, 1999). On...

  1. Laser ignition of bulk 1018 carbon steel in pure oxygen

    Nguyen, K.; Branch, M. C.

    1986-01-01

    Experiments were undertaken to study the ignition characteristics of bulk 1018 carbon steel in a pure oxygen environment. Cylindrical 1018 carbon steel specimens 5 mm in diameter and 5 mm high were ignited by a focused CW CO2 laser beam in a cool, static, pure oxygen environment at oxygen pressures ranging from 0.103 to 6.895 MPa. A two-color pyrometer was designed and used to measure the ignition temperatures of the specimens. The temperature history of a spot approximately 0.5 mm in diameter located at the center of the specimen top surface was recorded with a maximum time resolution of 25 microsec, and with an accuracy of a few percent. Ignition temperature of bulk 1018 carbon steel was identified from the temperature history curve with the aid of the light intensity curve. Results show that 1018 carbon steel specimens ignite at temperatures between 1388 and 1450 K, which are below the melting range of the alloy (1662-1685 K). The ignition temperature of 1018 carbon steel is mildly dependent on oxygen pressure over the range of oxygen pressure investigated in this study.

  2. 78 FR 42039 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Preliminary...

    2013-07-15

    ... (``HSLA'') steels, and the substrate for motor lamination steels. IF steels are recognized as low carbon... columbium), or both, added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels... Carbon Steel Flat Products from the People's Republic of China, 66 FR 59561 (November 29, 2001)....

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

    S. Dobatkin

    2008-07-01

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

  4. Development and processing of low carbon bainitic steels

    Suikkanen, P. (Pasi)

    2009-01-01

    Abstract The aim of this work was to study systematically the effects of composition and processing on austenite grain growth and static recrystallization (SRX) kinetics, austenite decomposition under controlled cooling as well as microstructures, mechanical properties and weldability of hot rolled low carbon bainitic (LCB) steels. The results showed that the coarsening of austenite grain structure is influenced by the chemical composition. Steels with Nb-Ti alloying exhibited fine and uni...

  5. MICROBIAL CORROSION OF MILD AND MEDIUM CARBON STEELS

    J. E.O. OVRI; S. I. OKEAHIALAM; O. O. ONYEMAOBI

    2013-01-01

    The role of bacteria in the corrosion of mild and medium carbon steels is reported. The steels were exposed to anaerobic and aerobic, and fresh water (control) environments. The corrosion rates were evaluated at intervals of seven days for a period of 42 days using weight loss and electrochemical methods. The corroded specimens were visually examined and majorities were found to have undergone general corrosion in the three environments (aerobic, anaerobic, and fresh water)....

  6. The anaerobic corrosion of carbon steel in concrete

    This is the final report of a 2 year programme aimed at (1) determining the rate of anaerobic corrosion of steel in concrete, (2) investigating the nature of the corrosion products formed on carbon steel embedded in cementitious material under anaerobic conditions and (3) evaluating the effect of hydrogen over-pressures on the rate of anaerobic corrosion. All experiments have been carried out at temperatures in the range 20-300C, ie ambient conditions. 4 refs.; 19 figs.; 6 tabs

  7. ESTIMATION OF IRREVERSIBLE DAMAGEABILITY AT FATIGUE OF CARBON STEEL

    I. O. Vakulenko

    2014-04-01

    Full Text Available Purpose. Damageability estimation of carbon steel in the conditions of cyclic loading. Methodology. The steel fragments of railway wheel rim and rail head served as material for research with chemical composition 0.65 % С, 0.67 % Mn, 0.3 % Si, 0.027 % P, 0.028 % S и 0.7 % C, 0.82 % Mn, 0.56 % Si, 0.025 % P, 0.029 % S accordingly. The microstructure of tested steels corresponded to the state of metal after a hot plastic deformation. The fatigue research was conducted in the conditions of symmetric bend using the proof-of-concept machine of type «Saturn-10». Full Wohler diagrams and the lines corresponding to forming of sub-and micro cracks were constructed. The distribution analysis of internal stresses in the metal under cyclic loading was carried out using the microhardness tester of PMT-3 type.Findings. On the basis of fatigue curves for high-carbon steels analysis the positions of borders dividing the areas of convertible and irreversible damages were determined. The article shows that with the growth of carbon concentration in the steel at invariability of the structural state an increase of fatigue limit is observed. At the same time the acceleration of processes, which determine transition terms from the stage of forming of submicrocracks to the microcracks occurs. The research of microhardness distribution in the metal after destruction confirmed the nature of carbon amount influence on the carbon steel characteristics. Originality. Regardless on the stages of breakdown site forming the carbon steels behavior at a fatigue is determined by the ration between the processes of strengthening and softening. At a cyclic loading the heterogeneity of internal stresses distribution decreases with the increase of distance from the destruction surface. Analysis of metal internal restructuring processes at fatigue loading made it possible to determine that at the stages prior to incubation period in the metal microvolumes the cells are already

  8. Increasing corrosion resistance of carbon steels by surface laser cladding

    Polsky, V. I.; Yakushin, V. L.; Dzhumaev, P. S.; Petrovsky, V. N.; Safonov, D. V.

    2016-04-01

    This paper presents results of investigation of the microstructure, elemental composition and corrosion resistance of the samples of low-alloy steel widely used in the engineering, after the application of laser cladding. The level of corrosion damage and the corrosion mechanism of cladded steel samples were established. The corrosion rate and installed discharge observed at the total destruction of cladding were obtained. The regularities of structure formation in the application of different powder compositions were obtained. The optimal powder composition that prevents corrosion of samples of low-carbon low-alloy steel was established.

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

    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.

  10. MICROBIAL CORROSION OF MILD AND MEDIUM CARBON STEELS

    J. E. O. OVRI

    2013-10-01

    Full Text Available The role of bacteria in the corrosion of mild and medium carbon steels is reported. The steels were exposed to anaerobic and aerobic, and fresh water (control environments. The corrosion rates were evaluated at intervals of seven days for a period of 42 days using weight loss and electrochemical methods. The corroded specimens were visually examined and majorities were found to have undergone general corrosion in the three environments (aerobic, anaerobic, and fresh water. The mild steel was found to corrode more than the medium carbon steel in anaerobic environment-mild steel: 6.43×10-4 mpy and -0.93 mV, due to limited available oxygen whilst it had -0.89 mV in aerobic and -0.77 mV in the fresh water. The medium carbon steel had -5.30×10-4 mpy and -0.91 mV in anaerobic: -0.84mV in aerobic and -0.74mV in freshwater.

  11. Content of nitrogen in waste petroleum carbon for steel industries

    Steel industries use refined carbon as an alloy for steel production. This alloy is produced from waste carbon from the distillation of the petroleum. The refined carbon, called recarburizer, is obtained by calcination at high temperature. Under these thermal conditions the organic molecules decompose and a fraction of the N2, S and H2, volatile material and moisture are released; while the carbon tends to develop a crystalline structure similar to graphite's. The right combination of calcinations temperature and time in the furnace can optimize the quality of the resulting product. The content of S and N2 has to be minimized for the use of calcined carbon in the steel industry. Nitrogen content should be reduced by two orders of magnitude, from 1% - 2% down to hundreds of ppm by weight. This work describes the activities undertaken to obtain calcined coke from petroleum from crude oil carbon that satisfies the requirements of the Mercosur standard 02:00-169 (Pending) for use as a carborizer in steels industries. To satisfy the requirements of the Mercosur standards NM 236:00 IRAM-IAS-NM so that graphite is used as a carburizer a content of 300 ppm maximum weight of nitrogen has to be obtained. So the first stage in this development is to define a production process for supplying calcined coke in the range of nitrogen concentrations required by the Mercosur standards (CW)

  12. Austenite Recrystallization and Controlled Rolling of Low Carbon Steels

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

    2006-01-01

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

  13. Initial Atmospheric Corrosion of Carbon Steel in Industrial Environment

    Han, Wei; Pan, Chen; Wang, Zhenyao; Yu, Guocai

    2015-02-01

    The initial corrosion behavior of carbon steel subjected to Shenyang industrial atmosphere has been investigated by weight-loss measurement, scanning electron microscopy observation, x-ray diffraction, auger electron spectroscopy, and electron probe microanalysis. The experimental results reveal that the corrosion kinetics of the initial corrosion of carbon steel in industrial atmosphere follows empirical equation D = At n , and there is a corrosion rate transition from corrosion acceleration to deceleration; the corrosion products are composed of γ-FeOOH, α-FeOOH, Fe3O4, as well as FeS which is related to the existence of sulfate-reducing bacteria in the rust layers. The effect of dust particles on the corrosion evolution of carbon steel has also been discussed.

  14. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    Hilbert, Lisbeth Rischel

    2000-01-01

    Abstract Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria, e.g. on pipelines buried in soil and on marine structures. MIC of...... carbon steel must be monitored on-line in order to provide an efficient protection and control the corrosion. A number of monitoring techniques is industrially used today, and the applicability and reliability of these for monitoring MIC is evaluated. Coupons and ER are recommended as necessary basic...... techniques even though localised corrosion rate cannot be measured. FSM measures general corrosion and detects localised corrosion, but the sensitivity is not high enough for monitoring initiation of pitting and small attacks. Electrochemical techniques as LPR and EIS give distorted data and unreliable...

  15. Metal magnetic memory signals from surface of low-carbon steel and low-carbon alloyed steel

    DONG Li-hong; XU Bin-shi; DONG Shi-yun; YE Ming-hui; CHEN Qun-zhi; WANG Dan; YIN Da-wei

    2007-01-01

    In order to investigate the regularity of metal magnetic signals of ferromagnetic materials under the effect of applied load, the static tensile test of Q235 steel and 18CrNiWA steel plate specimens were conducted and metal magnetic memory signals of specimens were measured during the test process.The influencing factors of metal magnetic memory signals and the relationship between axial appliedload and signals were analyzed. The fracture and microstructure of the specimens were observed.The results show that the magnetic signals corresponding to the measured points change linearly approximately with increasing axial load.The microstructure of Q235 steel is ferrite and perlite, whereas that of l8CrNiWA steel is bainite and low-carbon martensite.The fracture of these two kinds of specimens is ductile rupture;carbon content of specimen materials and dislocation glide give much contribution to the characterisffcs of magnetic curves.

  16. Trial manufacturing of titanium-carbon steel composite overpack

    Honma, Nobuyuki; Chiba, Takahiko; Tanai, Kenji [Japan Nuclear Cycle Development Inst., Waste Management and Fuel Cycle Research Center, Tokai, Ibaraki (Japan)

    1999-11-01

    This paper reports the results of design analysis and trial manufacturing of full-scale titanium-carbon steel composite overpacks. The overpack is one of the key components of the engineered barrier system, hence, it is necessary to confirm the applicability of current technique in their manufacture. The required thickness was calculated according to mechanical resistance analysis, based on models used in current nuclear facilities. The Adequacy of the calculated dimensions was confirmed by finite-element methods. To investigate the necessity of a radiation shielding function of the overpack, the irradiation from vitrified waste has been calculated. As a result, it was shown that shielding on handling and transport equipment is a more reasonable and practical approach than to increase thickness of overpack to attain a self-shielding capability. After the above investigation, trial manufacturing of full-scale model of titanium-carbon steel composite overpack has been carried out. For corrosion-resistant material, ASTM Grade-2 titanium was selected. The titanium layer was bonded individually to a cylindrical shell and fiat cover plates (top and bottom) made of carbon steel. For the cylindrical shell portion, a cylindrically formed titanium layer was fitted to the inner carbon steel vessel by shrinkage. For the flat cover plates (top and bottom), titanium plate material was coated by explosive bonding. Electron beam welding and gas metal arc welding were combined to weld of the cover plates to the body. No significant failure was evident from inspections of the fabrication process, and the applicability of current technology for manufacturing titanium-carbon steel composite overpack was confirmed. Future research and development items regarding titanium-carbon steel composite overpacks are also discussed. (author)

  17. Trial manufacturing of titanium-carbon steel composite overpack

    This paper reports the results of design analysis and trial manufacturing of full-scale titanium-carbon steel composite overpacks. The overpack is one of the key components of the engineered barrier system, hence, it is necessary to confirm the applicability of current technique in their manufacture. The required thickness was calculated according to mechanical resistance analysis, based on models used in current nuclear facilities. The Adequacy of the calculated dimensions was confirmed by finite-element methods. To investigate the necessity of a radiation shielding function of the overpack, the irradiation from vitrified waste has been calculated. As a result, it was shown that shielding on handling and transport equipment is a more reasonable and practical approach than to increase thickness of overpack to attain a self-shielding capability. After the above investigation, trial manufacturing of full-scale model of titanium-carbon steel composite overpack has been carried out. For corrosion-resistant material, ASTM Grade-2 titanium was selected. The titanium layer was bonded individually to a cylindrical shell and fiat cover plates (top and bottom) made of carbon steel. For the cylindrical shell portion, a cylindrically formed titanium layer was fitted to the inner carbon steel vessel by shrinkage. For the flat cover plates (top and bottom), titanium plate material was coated by explosive bonding. Electron beam welding and gas metal arc welding were combined to weld of the cover plates to the body. No significant failure was evident from inspections of the fabrication process, and the applicability of current technology for manufacturing titanium-carbon steel composite overpack was confirmed. Future research and development items regarding titanium-carbon steel composite overpacks are also discussed. (author)

  18. 76 FR 78882 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Affirmative Preliminary Determination of...

    2011-12-20

    ... Steel Plate From Canada, 66 FR 7617, 7618 (January 24, 2001)) (Canadian Plate), and accompanying Issued... this order is certain hot-rolled products of carbon steel and alloy steel, in coils, of approximately... International Trade Administration Carbon and Certain Alloy Steel Wire Rod From Mexico: Affirmative...

  19. Electrochemical noise from corroding carbon steel and aluminium

    Electrochemical noise measurements were conducted on carbon steel and aluminium in sodium chloride solutions. Noise parameters like standard deviation of potential and current, noise resistance, pitting index, noise power were studied for the purpose of measuring corrosion rate. These parameters compared well with the corrosion rate. Pitting index was not very reliable. Current noise was more close to the corrosion rates. General corrosion gave rise to white noise type of power spectrum while flicker noise type of spectrum was obtained from pitting attack. Sodium nitrite is shown to inhibit the corrosion of carbon steel. Aluminium corrodes in the early period of exposure and passivates during long exposure

  20. Modeling Corrosion Reactions of Steel in a Dilute Carbonate Solution

    Eliyan, Faysal Fayez; Alfantazi, Akram

    2016-02-01

    This research models the corrosion reactions of a high-strength steel in an aerated, dilute, carbonate solution during a single-cycle voltammetry. Based on a previous study (Eliyan et al. in J Mater Eng Perform 24(6):1-8, 2015) and a literature survey, the corrosion reactions of the cathodic reduction, anodic dissolution, and passivation, as well as the interfacial interactions and the chemistry of the corrosion products are illustrated in schematics. The paper provides a visual guide on the corrosion reactions for steel in carbonate solutions based on the available mechanistic details that were reported and are still being investigated in literature.

  1. Residual stress measurements in carbon steel

    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.

  2. Volatile corrosion inhibitor film formation on carbon steel surface and its inhibition effect on the atmospheric corrosion of carbon steel

    A novel volatile corrosion inhibitor (VCI), bis-piperidiniummethyl-urea (BPMU), was developed for temporary protection of carbon steel. Its vapor corrosion inhibition property was evaluated under simulated operational conditions. Electrochemical impedance spectroscopy was applied to study the inhibition effect of BPMU on the corrosion of carbon steel with a thin stimulated atmospheric corrosion water layers. Adsorption of BPMU on carbon steel surfaces was investigated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The results indicate that BPMU can form a protective film on the metal surface, which protects the metal against further corrosion. The structure of the protective film was suggested as one BPMU molecule chelated with one Fe atom to form a complex with two hexa-rings

  3. Volatile corrosion inhibitor film formation on carbon steel surface and its inhibition effect on the atmospheric corrosion of carbon steel

    Zhang, Da-quan; An, Zhong-xun; Pan, Qing-yi; Gao, Li-xin; Zhou, Guo-ding

    2006-11-01

    A novel volatile corrosion inhibitor (VCI), bis-piperidiniummethyl-urea (BPMU), was developed for temporary protection of carbon steel. Its vapor corrosion inhibition property was evaluated under simulated operational conditions. Electrochemical impedance spectroscopy was applied to study the inhibition effect of BPMU on the corrosion of carbon steel with a thin stimulated atmospheric corrosion water layers. Adsorption of BPMU on carbon steel surfaces was investigated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The results indicate that BPMU can form a protective film on the metal surface, which protects the metal against further corrosion. The structure of the protective film was suggested as one BPMU molecule chelated with one Fe atom to form a complex with two hexa-rings.

  4. 76 FR 45509 - Final Results of Antidumping Duty Changed Circumstances Review: Carbon and Certain Alloy Steel...

    2011-07-29

    ... Circumstances Review: Carbon and Certain Alloy Steel Wire Rod from Mexico, 75 FR 67685 (November 3, 2010...: Carbon and Certain Alloy Steel Wire Rod From Mexico, 71 FR 27989 (May 15, 2006). Notification This notice... of the Order The merchandise subject to this order is certain hot-rolled products of carbon steel...

  5. 78 FR 34340 - Welded Carbon Steel Standard Pipe and Tube Products From Turkey: Preliminary Results of...

    2013-06-07

    ... Order; Welded Carbon Steel Standard Pipe and Tube Products from Turkey, 51 FR 17784 (May 15, 1986). The... International Trade Administration Welded Carbon Steel Standard Pipe and Tube Products From Turkey: Preliminary... antidumping duty order on welded carbon steel standard pipe and tube products (welded pipe and tube)...

  6. Carbon exchange between steel and sodium as a corrosion phenomenon

    New analytical methods are applied to measure carbon in liquid sodium in the concentration range below 1 μg C/gNa. The carbon exchange between sodium and austenitic steel under decarburising conditions can be understood on the basis of the results of these analyses. The decarburisation of austenitic steel by sodium may cause a corrosive effect of the surface region of the materials. Some tests with the steel no. 1.4948 have demonstrated a reduction of its creep-rupture strength at 550deg C. The corrosion due to decarburisation proceeds slowly, specimens with a larger diameter were not affected, a significant reduction of the creep-rupture strength did not occur. (orig.)

  7. Atmospheric corrosion of carbon steel in the prairie regions

    Shaw, W.J. [Calgary Univ., AB (Canada). Dept. of Mechanical and Manufacturing Engineering; Andersson, J.I. [Husky Oil Operations Ltd., Calgary, AB (Canada)

    2010-07-01

    A study of atmospheric corrosion and carbon steel located in the prairie regions of Canada was presented. The study considered corrosion behaviour as well as the standards currently used to establish and predict corrosion in atmospheric conditions. The aim of the study was to develop an accurate predictive method of establishing corrosion amounts over time. The controlling parameters for atmospheric corrosion included acidic rainfall; temperature and humidity; time of wetness; and the presence of major contaminants such as sulfur dioxide (SO{sub 2}). The predictive approach involved the study of a protective film of magnetite iron oxide that establishes itself on carbon steel over time. The presence of the film provides increased atmospheric corrosion resistance. An analysis of the atmospheric corrosion of steel tanks at the Hardisty terminal was used to demonstrate the method. 22 refs., 5 tabs., 7 figs.

  8. Investigation of boron segregation in low carbon steel

    J. Lis

    2011-04-01

    Full Text Available Traces of born in the range 0,002-0,009 % are usually added to many grades of steel. The effect of boron on phase transformations and hardenability of low carbon low alloy steels depends on the form of its behavior in solid solution either in segregations or in precipitations. Temperature and cooling rate determine the existence of boron segregations on grain boundaries. In present paper simulations of boron concentrations were calculated with computer programme DICTRA for low carbon 0,08 %C steel with 0,006 % boron. Investigations were carried out for temperature 1300 – 700°C and cooling rates from 1°C/s to 100°C/s. The changes of boron concentrations in austenite and ferrite after commencement of γ→α phase transformation were established.

  9. Oxidation of ultra low carbon and silicon bearing steels

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

    2010-06-15

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

  10. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    Hilbert, Lisbeth Rischel

    2000-01-01

    Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria, e.g. on pipelines buried in soil and on marine structures. MIC of carbon steel must be monitored on-line in order to provide an efficient protection and...... control the corrosion. A number of monitoring techniques is industrially used today, and the applicability and reliability of these for monitoring MIC is evaluated. Coupons and ER are recommended as necessary basic techniques even though localised corrosion rate cannot be measured. FSM measures general...... corrosion and detects localised corrosion, but the sensitivity is not high enough for monitoring initiation of pitting and small attacks. Electrochemical techniques as LPR and EIS give distorted data and unreliable corrosion rates, when biofilm and corrosion products cover the steel surface. However, EIS...

  11. Corrosion behavior of carbon steels under tuff repository environmental conditions

    Carbon steels may be used for borehole liners in a potential high-level nuclear waste repository in tuff in Nevada. Borehole liners are needed to facilitate emplacement of the waste packages and to facilitate retrieval of the packages, if required. Corrosion rates of low carbon structural steels AISI 1020 and ASTM A-36 were determined in J-13 well water and in saturated steam at 1000C. Tests were conducted in air-sparged J-13 water to attain more oxidizing conditions representative of irradiated aqueous environments. A limited number of irradiation corrosion and stress corrosion tests were performed. Chromium-molybdenum alloy steels and cast irons were also tested. These materials showed lower general corrosion but were susceptible to stress corrosion cracking when welded. 4 references, 4 tables

  12. Friction and wear characteristics of carbon steels in vacuum

    Verkin, B. I.; Lyubarskiy, I. M.; Udovenko, V. F.; Guslyakov, A. A.

    1974-01-01

    The nature of carbon steel friction and wear under vacuum conditions is described within the framework of general friction and wear theory. Friction is considered a dynamic process and wear is considered to be the result of a continuous sequence of transitions of the friction surface material from one state into another.

  13. Carbon distribution in bainitic steel subjected to deformation

    Ivanov, Yu. F., E-mail: yufi55@mail.ru [Institute of High Current Electronics SB RAS, Tomsk, 634055 (Russian Federation); National Research Tomsk State University, Tomsk, 634050 (Russian Federation); Nikitina, E. N., E-mail: Nikitina-EN@mail.ru; Gromov, V. E., E-mail: gromov@physics.sibsiu.ru [Siberian State Industrial University, Novokuznetsk, 654007 (Russian Federation)

    2015-10-27

    Analysis of the formation and evolution of carbide phase in medium carbon steel with a bainitic structure during compressive deformation was performed by means of transmission electron diffraction microscopy. Qualitative transformations in carbide phase medium size particles, their density and volume concentration depended on the degree of deformation.

  14. Nondestructive evaluation of residual stress in low-carbon steel

    Salama, K.

    1984-01-01

    The effects of the preferred orientation on the temperature dependence of ultrasonic velocity in low carbon steels are investigated. The sensitivity of the acousto-elastic constant to changes in microstructure is assessed as well as the possibility of determining some mechanical properties of a material by measuring the acousto-elastic constant.

  15. Microbial corrosion of carbon steel by sulfate-reducing bacteria:

    Nielsen, Lars Vendelbo; Hilbert, Lisbeth Rischel

    1997-01-01

    Electrochemical measurements (EIS and DC-polarisation curves) have been conducted on carbon steel coupons exposed in SRB-active environments. Results from EIS measurements show that very large interfacial capacities are found in such systems, and consequently high capacitive currents are to be ex...... misleading conclusion that increasing corrosion rates are caused by cathodic depolarisation in SRB-active environments....

  16. Carbon distribution in bainitic steel subjected to deformation

    Analysis of the formation and evolution of carbide phase in medium carbon steel with a bainitic structure during compressive deformation was performed by means of transmission electron diffraction microscopy. Qualitative transformations in carbide phase medium size particles, their density and volume concentration depended on the degree of deformation

  17. Vanadium Effect on a Medium Carbon Forging Steel

    Carlos Garcia-Mateo

    2016-05-01

    Full Text Available In the present work the influence of vanadium on the hardenability and the bainitic transformation of a medium carbon steel is analyzed. While V in solid solution enhances the former, it hardly affects bainitic transformation. The results also reveal an unexpected result, an increase of the prior austenite grain size as the V content increases.

  18. Laser-ultrasonic absorption measurements in low carbon steels

    Moreau, A.; Lord, M.; Levesque, D.; Dubois, M.; Bussiere, J.F. [Institut des Materiaux Industriels, Boucherville, Que. (Canada)

    2000-09-28

    We have refined the contactless laser-ultrasound reverberation technique to measure ultrasonic absorption on small metallic samples. In this technique, a sample is supported by a holder which is ultrasonically decoupled from the sample. A pulsed laser is used to generate an acoustic pulse. After the pulse has mode converted and scattered sufficiently to fully insonify the sample, the decrease in the noise-like ultrasonic signal is recorded as a function of time using a laser-interferometer. A joint time-frequency analysis technique is used to extract an absorption spectrum from the signal. In this paper, the technique is demonstrated in a frequency bandwidth ranging from 1 to 7 MHz, and in a dynamic range of 0.003 to 0.3 dB {mu}s{sup -1}. Measurements made on samples of three low-carbon steel grades, namely ultra low carbon (ULC), low carbon (LC), and high strength, low-alloy steels (HSLA), clearly show that ultrasonic absorption varies with steel grade. The technique was utilized to study the effect of a magnetic field on the ultrasonic absorption of an annealed ultra low carbon steel sample. It was found that magnetoelastic effects are responsible for a large fraction of the total absorption. (orig.)

  19. Numerical simulation and experimental investigation of laser dissimilar welding of carbon steel and austenitic stainless steel

    Nekouie Esfahani, M. R.; Coupland, J.; Marimuthu, S.

    2015-07-01

    This study reports an experimental and numerical investigation on controlling the microstructure and brittle phase formation during laser dissimilar welding of carbon steel to austenitic stainless steel. The significance of alloying composition and cooling rate were experimentally investigated. The investigation revealed that above a certain specific point energy the material within the melt pool is well mixed and the laser beam position can be used to control the mechanical properties of the joint. The heat-affected zone within the high-carbon steel has significantly higher hardness than the weld area, which severely undermines the weld quality. A sequentially coupled thermo-metallurgical model was developed to investigate various heat-treatment methodology and subsequently control the microstructure of the HAZ. Strategies to control the composition leading to dramatic changes in hardness, microstructure and service performance of the dissimilar laser welded fusion zone are discussed.

  20. 75 FR 64254 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products From Brazil; Final Results of...

    2010-10-19

    ... ] (HSLA) steels, and the substrate for motor lamination steels. IF steels are recognized as low carbon... and nitrogen elements. HSLA steels are recognized as steels with micro- alloying levels of elements... Carbon-Quality Steel Products from the Russian Federation, 65 FR 5510, 5518 (February 4, 2000)...

  1. 75 FR 19369 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products from Brazil: Preliminary Results of...

    2010-04-14

    ...-free (IF)) steels, high strength low alloy (HSLA) steels, and the substrate for motor lamination steels... and/or niobium added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels... Carbon Quality Steel Products from Brazil, 67 FR 11093 (March 12, 2002) (Antidumping Order). ] On March...

  2. 76 FR 66901 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Final...

    2011-10-28

    ...), or both, added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels with...'') steels, and the substrate for motor lamination steels. IF steels are recognized as low carbon steels with... Rescind the Review, 76 FR 48143 (August 8, 2011) (``Preliminary Results''). ] DATES: Effective...

  3. 75 FR 4779 - Certain Cut-to-Length Carbon-Quality Steel Plate Products From Italy: Preliminary Results of...

    2010-01-29

    ... (HSLA) steels. HSLA steels are recognized as steels with micro-alloying levels of elements such as...-Rolled Flat-Rolled Carbon-Quality Steel Products From Japan, 64 FR 24329 (May 6, 1999). In Nippon Steel... Value: Certain Cut-To-Length Carbon-Quality Steel Plate Products From Italy, 64 FR 41213 (July 29,...

  4. 77 FR 32513 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From the Russian Federation; Preliminary...

    2012-06-01

    ... alloy (``HSLA'') steels, and the substrate for motor lamination steels. IF steels are recognized as low... carbon and nitrogen elements. HSLA steels are recognized as steels with micro-alloying levels of elements... Carbon-Quality Steel Products From the Russian Federation, 64 FR 38626 (July 19, 1999). Likewise,...

  5. Corrosion behaviour of carbon steel in the Tournemire clay

    Carbon steels are possible materials for the fabrication of nuclear waste containers for long term geological disposal in argillaceous environments. Experimental studies of the corrosion behaviour of such materials has been conducted in various conditions. Concerning the numerous laboratory experiments, these conditions (water and clay mixture or compacted clay) mainly concern the bentonite clay that would be used for the engineered barrier. On the opposite, only few in-situ experiments has been conducted directly in the local clay of the repository site (such as Boom clay, etc.). In order to better estimate the corrosion behaviour of carbon steels in natural clay site conditions, an experimental study has been conducted jointly by EDF and IRSN in the argillaceous French site of Tournemire. In this study, A42 carbon steel specimens have been exposed in 3 different zones of the Tournemire clay formation. The first type of environmental conditions concerns a zone where the clay has not been affected by the excavation (EDZ) of the main tunnel neither by the main fracture zone of the clay formation. The second and third ones are located in the EDZ of the tunnel. In the second zone, an additional aerated water flows from the tunnel, whereas it does not in the third place. Some carbon steel specimens have been extracted after several years of exposure to these conditions. The average corrosion rate has been measured by the weight loss technique and the pitting corrosion depth has been evaluated under an optical microscope. Corrosion products have also been characterised by scanning electron microscopy and X-ray diffraction technique. Results are then discussed regarding the surrounding environmental conditions. Calculations of the oxygen transport from the tunnel through the clay and of the clay re-saturation can explain, in a first approach, the corrosion behaviour of the carbon steel in the different tested zones. (authors)

  6. Mechanical properties and fatigue strength of high manganese non-magnetic steel/carbon steel welded joints

    The dissimilar materials welded joints of high manganese non-magnetic steel/carbon steel (hereafter referred to as DMW joints), in which weld defects such as hot crack or blowhole are not found, were the good quality. Tensile strength of DMW joints was 10% higher than that of the base metal of carbon steel. In the bend tests, the DMW joints showed the good ductility without crack. Charpy absorbed energy at 0(degC) of the DMW joints was over 120(J) in the bond where it seems to be the lowest. Large hardening or softening was not detected in the heat affected zone. Fatigue strength of the DMW joints is almost the same with that of the welded joints of carbon steel/carbon steel. As the fatigue strength of the DMW joints exceeds the fatigue design standard curve of JSSC for carbon steel welded joints, the DMW joints can be treated the same as the welded joints of carbon steel/carbon steel of which strength is lower than that of high manganese non-magnetic steel, from the viewpoint of the fatigue design. (author)

  7. Elastic Sag Property of Low Carbon Martensite Spring Steel

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

    2004-01-01

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

  8. CARBON DIFFUSION IN CARBON-SUPERSATURATED 9CR-1MO STEEL: ANOMALOUS TEMPERATURE DEPENDENCE OF CARBON DIFFUSIVITY

    Čermák, Jiří; Král, Lubomír

    Ostrava : Tanger Ltd, 2014. ISBN 978-80-87294-52-9. [Metal 2014. International Conference on Metallurgy and Materials /23./. Brno (CZ), 21.05.2014-23.05.2014] R&D Projects: GA ČR(CZ) GAP108/11/0148; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : Diffusion * Carbon * phase decomposition * Carbon-supersaturation * Cr-Mo steels Subject RIV: BJ - Thermodynamics http://www.metal2014.com/cz/zobrazit-seznam-prispevku/2498-carbon-diffusion-in-carbon-supersaturated-9cr-1mo-steel-anomalous-temperature-dependence-of-carbon-diffusivity/

  9. Intragranular ferrite in inoculated low-carbon steels

    Inoculated low-carbon plate steels have been developed which provide improved low temperature toughness compared with conventional HSLA steels, and also exhibit better weldability with high heat input welding processes. These characteristics make inoculated steels suitable for large structures in severe environments. The improved toughness and weldability are attributed to the formation of microstructures containing fine, intragranular ferrite which nucleates on inclusion dispersions, similar to acicular ferrite formation in weld metals. The development of various inoculated steels is described and the role of inclusions in intragranular ferrite formation is reviewed. The primary role of inclusions is to provide heterogeneous nucleation sites, but nucleation appears to be enhanced to a certain extent by a number of other phenomena at the inclusion surface. Various phases have been shown to enhance intragranular ferrite nucleation, and the most effective of these for inoculation of plate steels are phases rich in titanium and oxygen. Inoculated Ti-O steels have found limited commercial acceptance, but further development depends on achievement of reliable steelmaking technology to optimise microstructural control with particles

  10. Morphological and microstructural studies on aluminizing coating of carbon steel

    Hot dip aluminizing is one of the most effective methods of surface protection for steels and is gradually gaining popularity. The morphology and microstructure of an inter-metallic layer form on the surface of low carbon steel by hot dip aluminization treatment had been studied in detail. This effect has been investigated using optical and scanning electron microscopy, and X-ray diffraction. The result shows that the reaction between the steel and the molten aluminium leads to the formation of Fe–Al inter-metallic compounds on the steel surface. X-ray diffraction and electron microscopic studies showed that a two layer coating was formed consisting of an external Al layer and a (Fe2Al5) inter metallic on top of the substrate after hot dip aluminizing process. The inter-metallic layer is ‘thick’ and exhibits a finger-like growth into the steel. Microhardness testing shown that the intermetallic layer has high hardness followed by steel substrate and the lowest hardness was Al layer

  11. Weldability of Low Carbon Transformation Induced Plasticity Steel

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

    2008-01-01

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

  12. Gas phase hydrogen permeation in alpha titanium and carbon steels

    Johnson, D. L.; Shah, K. K.; Reeves, B. H.; Gadgeel, V. L.

    1980-01-01

    Commercially pure titanium and heats of Armco ingot iron and steels containing from 0.008-1.23 w/oC were annealed or normalized and machined into hollow cylinders. Coefficients of diffusion for alpha-Ti and alpha-Fe were determined by the lag-time technique. Steady state permeation experiments yield first power pressure dependence for alpha-Ti and Sievert's law square root dependence for Armco iron and carbon steels. As in the case of diffusion, permeation data confirm that alpha-titanium is subject to at least partial phase boundary reaction control while the steels are purely diffusion controlled. The permeation rate in steels also decreases as the carbon content increases. As a consequence of Sievert's law, the computed hydrogen solubility decreases as the carbon content increases. This decreases in explained in terms of hydrogen trapping at carbide interfaces. Oxidizing and nitriding the surfaces of alpha-titanium membranes result in a decrease in the permeation rate for such treatment on the gas inlet surfaces but resulted in a slight increase in the rate for such treatment on the gas outlet surfaces. This is explained in terms of a discontinuous TiH2 layer.

  13. Anticorrosive Influence of Acetobacter aceti Biofilms on Carbon Steel

    France, Danielle Cook

    2016-07-01

    Microbiologically influenced corrosion (MIC) of carbon steel infrastructure is an emerging environmental and cost issue for the ethanol fuel industry, yet its examination lacks rigorous quantification of microbiological parameters that could reveal effective intervention strategies. To quantitatively characterize the effect of cell concentration on MIC of carbon steel, numbers of bacteria exposed to test coupons were systematically controlled to span four orders of magnitude throughout a seven-day test. The bacterium studied, Acetobacter aceti, has been found in ethanol fuel environments and can convert ethanol to the corrosive species acetic acid. A. aceti biofilms formed during the test were qualitatively evaluated with fluorescence microscopy, and steel surfaces were characterized by scanning electron microscopy. During exposure, biofilms developed more quickly, and test reactor pH decreased at a faster rate, when cell exposure was higher. Resulting corrosion rates, however, were inversely proportional to cell exposure, indicating that A. aceti biofilms are able to protect carbon steel surfaces from corrosion. This is a novel demonstration of corrosion inhibition by an acid-producing bacterium that occurs naturally in corrosive environments. Mitigation techniques for MIC that harness the power of microbial communities have the potential to be scalable, inexpensive, and green solutions to industrial problems.

  14. Mechanistic Understanding Of Caustic Cracking Of Carbon Steels

    Liquid waste generated by the PUREX process for separation of nuclear materials is concentrated and stored in Type IV single-shell carbon steel tanks at the Savannah River Site (SRS). The Type IV tanks for this waste do not have cooling coils and have not undergone heat treatment to stress-relieve the tanks. After the waste is concentrated by evaporation, it becomes very alkaline and can cause stress corrosion cracking (SCC) and pitting corrosion of the tank materials. SRS has experienced leakage from non-stress-relieved waste tanks constructed of A285 carbon steel and pitting of A212 carbon steel tanks in the vapor space. An investigation of tank materials has been undertaken at SRS to develop a basic understanding of caustic SCC of A285 and A212 grade carbon steels exposed to aqueous solutions, primarily containing sodium hydroxide (NaOH), sodium nitrate (NaNO3), and sodium nitrite (NaNO2) at temperatures relevant to the operating conditions of both the F and H area plants. This report presents the results of this corrosion testing program. Electrochemical tests were designed using unstressed coupons in a simulated tank environment. The purpose of this testing was to determine the corrosion susceptibility of the tank materials as a function of chemical concentration, pH, and temperature. A285 and A516 (simulates A212 carbon steel) coupons were used to investigate differences in the corrosion of these carbon steels. Electrochemical testing included measurement of the corrosion potential and polarization resistance as well as cyclic potentiodynamic polarization (CPP) testing of coupons. From the CPP experiments, corrosion characteristics were determined including: corrosion potential (Ecorr), pitting or breakdown potential (Epit), and repassivation potential (Eprot). CPP results showed no indications of localized corrosion, such as pitting, and all samples showed the formation of a stable passive layer as evidenced by the positive hysteresis during the scan

  15. Aerosol measurements from plasma torch cuts on stainless steel, carbon steel, and aluminum

    The main purpose of this project is to quantify aerosol particle size and generation rates produced by a plasma torch whencutting stainless steel, carbon steel and aluminum. the plasma torch is a common cutting tool used in the dismantling of nuclear facilities. Eventually, other cutting tools will be characterized and the information will be compiled in a user guide to aid in theplanning of both D ampersand D and other cutting operations. The data will be taken from controlled laboratory experiments on uncontaminated metals and field samples taken during D ampersand D operations at ANL nuclear facilities. The plasma torch data was collected from laboratory cutting tests conducted inside of a closed, filtered chamber. The particle size distributions were determined by isokinetically sampling the exhaust duct using a cascade impactor. Cuts on different thicknesses showed there was no observable dependence of the aerosol quantity produced as a function of material thickness for carbon steel. However, data for both stainless steel and aluminum revealed that the aerosol mass produced for these materials appear to have some dependance on thickness, with thinner materials producing tmore aerosols. The results of the laboratory cutting tests show that most measured particle size distributions are bimodal with one mode at about 0.2 μm and the other at about 10 μm. The average Mass Median Aerodynamic Diameters (MMAD's) for these tests are 0.36 ±0.08 μm for stainless steel, 0.48 ±0.17μm for aluminum and 0.52±0.12 μm for carbon steel

  16. Effects of tempering on internal friction of carbon steels

    Hoyos, J.J., E-mail: jjhoyos@unal.edu.co [Grupo de Ciencia y Tecnologia de los Materiales, Universidad Nacional de Colombia, Sede Medellin, Carrera 80 Numero 65-223, Medellin (Colombia); Ghilarducci, A.A., E-mail: friccion@cab.cnea.gov.ar [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, Instituto Balseiro-Universidad Nacional de Cuyo, Consejo Nacional de Investigaciones Cientificas y Tecnologicas, Av. Bustillo 9500, 8400 Bariloche RN (Argentina); Salva, H.R., E-mail: salva@cab.cnea.gov.ar [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, Instituto Balseiro-Universidad Nacional de Cuyo, Consejo Nacional de Investigaciones Cientificas y Tecnologicas, Av. Bustillo 9500, 8400 Bariloche RN (Argentina); Chaves, C.A., E-mail: cachaves@unal.edu.co [Grupo de Ciencia y Tecnologia de los Materiales, Universidad Nacional de Colombia, Sede Medellin, Carrera 80 Numero 65-223, Medellin (Colombia); Velez, J.M., E-mail: jmvelez@unal.edu.co [Grupo de Ciencia y Tecnologia de los Materiales, Universidad Nacional de Colombia, Sede Medellin, Carrera 80 Numero 65-223, Medellin (Colombia)

    2011-04-15

    Research highlights: {yields} Time tempering dependent microstructure of two steels is studied by internal friction. {yields} Internal friction indicates the interactions of dislocations with carbon and carbides. {yields} Internal friction detects the first stage of tempering. {yields} Precipitation hardening is detected by the decrease in the background. - Abstract: Two steels containing 0.626 and 0.71 wt.% carbon have been studied to determine the effects of tempering on the microstructure and the internal friction. The steels were annealed at 1093 K, quenched into water and tempered for 60 min at 423 K, 573 K and 723 K. The increase of the tempering time diminishes the martensite tetragonality due to the redistribution of carbon atoms from octahedrical interstitial sites to dislocations. Internal friction spectrum is decomposed into five peaks and an exponential background, which are attributed to the carbide precipitation and the dislocation relaxation process. Simultaneous presence of peaks P1 and P2 indicates the interaction of dislocations with the segregated carbon and carbide precipitate.

  17. Effects of tempering on internal friction of carbon steels

    Research highlights: → Time tempering dependent microstructure of two steels is studied by internal friction. → Internal friction indicates the interactions of dislocations with carbon and carbides. → Internal friction detects the first stage of tempering. → Precipitation hardening is detected by the decrease in the background. - Abstract: Two steels containing 0.626 and 0.71 wt.% carbon have been studied to determine the effects of tempering on the microstructure and the internal friction. The steels were annealed at 1093 K, quenched into water and tempered for 60 min at 423 K, 573 K and 723 K. The increase of the tempering time diminishes the martensite tetragonality due to the redistribution of carbon atoms from octahedrical interstitial sites to dislocations. Internal friction spectrum is decomposed into five peaks and an exponential background, which are attributed to the carbide precipitation and the dislocation relaxation process. Simultaneous presence of peaks P1 and P2 indicates the interaction of dislocations with the segregated carbon and carbide precipitate.

  18. Modeling the Electrical Contact Resistance at Steel-Carbon Interfaces

    Brimmo, Ayoola T.; Hassan, Mohamed I.

    2016-01-01

    In the aluminum smelting industry, electrical contact resistance at the stub-carbon (steel-carbon) interface has been recurrently reported to be of magnitudes that legitimately necessitate concern. Mitigating this via finite element modeling has been the focus of a number of investigations, with the pressure- and temperature-dependent contact resistance relation frequently cited as a factor that limits the accuracy of such models. In this study, pressure- and temperature-dependent relations are derived from the most extensively cited works that have experimentally characterized the electrical contact resistance at these contacts. These relations are applied in a validated thermo-electro-mechanical finite element model used to estimate the voltage drop across a steel-carbon laboratory setup. By comparing the models' estimate of the contact electrical resistance with experimental measurements, we deduce the applicability of the different relations over a range of temperatures. The ultimate goal of this study is to apply mathematical modeling in providing pressure- and temperature-dependent relations that best describe the steel-carbon electrical contact resistance and identify the best fit relation at specific thermodynamic conditions.

  19. Low Carbon Steel Processed by Equal Channel Angular Warm Pressing

    Zrnik, J.

    2007-01-01

    Full Text Available Low carbon steel AISI 10 was subjected to a severe plastic deformation technique called Equal Angular Channel Pressing (ECAP at different increased temperatures. The steel was subjected to ECAP with channel’s angle j = 90°, at different temperature in range of 150 - 300 °C. The number of passes at each temperature was N = 3. Light, scanning electron microscopy (SEM and transmission electron microscopy (TEM of thin foils were used to study the formation of substructure and ultrafine grains in deformed specimens. The size of newly born polygonized grains (subgrains and/or submicrocrystalline grains is in range of 300 - 500 mm. The formation of such of predominant submicrocrystalline structure resulted in significant increase of yield stress [Re] and tensile strength of the steel [Rm].

  20. Corrosion and Stress Corrosion Behaviors of Low and Medium Carbon Steels in Agro-Fluid Media

    Ayo Samuel AFOLABI

    2007-01-01

    Full Text Available Investigations were carried out to study critically the corrosion behaviour and Stress Corrosion Cracking (SCC of low and medium carbon steels in cassava and cocoa extracts by weight loss measurement and constant extension to fracture method respectively. The results obtained showed that medium carbon steel is more susceptible to corrosion than low carbon steel in both media. SCC is also more in medium carbon steel than low carbon steel in the two media under study. These deductions are due to higher carbon content in medium carbon steel coupled with various aggressive corrosion constituents contained in these media. Hydrogen embrittlement, as well as carbon cracking, is responsible for SCC of these materials in the agro-fluid media.

  1. Leaching modelling of slurry-phase carbonated steel slag.

    Costa, G; Polettini, A; Pomi, R; Stramazzo, A

    2016-01-25

    In the present work the influence of accelerated mineral carbonation on the leaching behaviour of basic oxygen furnace steel slag was investigated. The environmental behaviour of the material as evaluated through the release of major elements and toxic metals under varying pH conditions was the main focus of the study. Geochemical modelling of the eluates was used to derive a theoretical description of the underlying leaching phenomena for the carbonated material as compared to the original slag. Among the investigated elements, Ca and Si were most appreciably affected by carbonation. A very clear effect of carbonation on leaching was observed for silicate phases, and lower-Ca/Si-ratio minerals were found to control leaching in carbonated slag eluates as compared to the corresponding untreated slag sample as a result of Ca depletion from the residual slag particles. Clear evidence was also gained of solubility control for Ca, Mg and Mn by a number of carbonate minerals, indicating a significant involvement of the original slag constituents in the carbonation process. The release of toxic metals (Zn, V, Cr, Mo) was found to be variously affected by carbonation, owing to different mechanisms including pH changes, dissolution/precipitation of carbonates as well as sorption onto reactive mineral surfaces. The leaching test results were used to derive further considerations on the expected metal release levels on the basis of specific assumptions on the relevant pH domains for the untreated and carbonated slag. PMID:26489916

  2. 77 FR 64468 - Circular Welded Carbon-Quality Steel Pipe From India: Final Affirmative Countervailing Duty...

    2012-10-22

    ...; Countervailing Duties, 62 FR 27296, 27323 (May 19, 1997), and Circular Welded Carbon-Quality Steel Pipe From... Countervailing Duty Determination: Certain Hot-Rolled Carbon Steel Flat Products From Argentina, 66 FR 37007... Concrete Steel Wire Strand From India, 68 FR 68356 (December 8, 2003). We determine the...

  3. 75 FR 16439 - Certain Welded Carbon Steel Standard Pipe From Turkey: Preliminary Results of Countervailing Duty...

    2010-04-01

    ... Steel Pipe and Tube Products from Turkey, 51 FR 7984 (March 7, 1986). On March 2, 2009, the Department... Administrative Review: Certain Welded Carbon Steel Standard Pipe from Turkey, 72 FR 62837, 62838 (November 7...: Certain Welded Carbon Steel Standard Pipe from Turkey, 73 FR 12080 (March 6, 2008). To calculate the...

  4. The Study on 400 MPa Class Plain Carbon Structure Steel

    ZHANG Hong-mei; LI Sheng-li; LI Wei-juan; DU Lin-xiu; WANG Guo-dong

    2004-01-01

    New generation of structure steel has been developed to meet the uninterruptedly increasing needs of the economic construction and development of society, and such material is characterized by ultra-fine grain. In this paper, 400MPa class plain carbon structure steel has been studied, making its yield strength doubled and service life doubled on the basis of good comprehensive properties in large quantity utilization. The deformation behavior and the stain induced transformation of SS400 steel at different temperature were investigated in the laboratory, and the industrial rolling test was carried out in 2 050mm HSM of Baosteel. Not only the laboratory studies but also the industrial test show that the technical route of the experimentis correct and the industrial test results on the basis of low carbon plain steel indicate that the grain size of ferrite was near to 4 ~ 5 μm, elongation was more than 30% , impact property was good, the yield strength can reach 400 MPa.

  5. A new nanoscale metastable iron phase in carbon steels.

    Liu, Tianwei; Zhang, Danxia; Liu, Qing; Zheng, Yanjun; Su, Yanjing; Zhao, Xinqing; Yin, Jiang; Song, Minghui; Ping, Dehai

    2015-01-01

    Metastable ω phase is common in body-centred cubic (bcc) metals and alloys, including high-alloying steels. Recent theoretical calculations also suggest that the ω structure may act as an intermediate phase for face-centred cubic (fcc)-to-bcc transformation. Thus far, the role of the ω phase played in fcc-bcc martensitic transformation in carbon steels has not been reported. In previous investigations on martensitic carbon steels, extra electron diffraction spots were frequently observed by transmission electron microscopy (TEM), and these spots were historically ascribed to the diffraction arising from either internal twins or carbides. In this paper, an intensive TEM investigation revealed that the extra spots are in fact attributed to the metastable ω phase in particle-like morphology with an overall size of several or dozens of nanometres. The strict orientation relationships between the ω phase and the ferrite matrix are in good agreement with those of the hexagonal (P6/mmm) ω phase in other bcc metals and alloys. The identification of the ω phase as well as the extra diffraction spots might provide a clue to help understand the physical mechanism of martensitic transformation in steels. PMID:26503890

  6. Draft guideline of NDI for low carbon stainless steel

    The in-service inspection for the equipment at the nuclear power plants is obligated for to the electric power utilities and is implemented as the periodical utility inspection. On the other hand, the stress corrosion cracks emerge in low carbon stainless steel and the verification of the non-destructive inspection technologies becomes urgent business. JNES implemented a verification test about flaw detectability and sizing accuracy of the non-destructive inspection technologies to the reactor core shroud and the nuclear reactor recirculation pipe made of the low carbon stainless steel, and worked out the draft guideline of the non-destructive inspection. In this paper, we reports on the part of the result of the verification test which JNES implemented. (author)

  7. Stress Modeling of the Laser Drilling Process in Carbon Steel

    A laser machining process has been applied in many manufacturing fields and it provides an excellent energy control for treating materials. However, a heat effect during laser machining can deteriorate material properties. Specifically, a thermally induced stress can be a problem in laser-machined structures on a metal surface. In this study, temperature and stress on cold-rolled carbon steel sheet machined with laser hole drilling were explored in an experimental approach and a numerical method. Stresses by temperature gradients inside the materials were generated in fast cooling. The stresses were measured by using a hole-drilling method and the material properties of carbon steel (Scp-S) were obtained in the experiment. It was found that the stress predicted from the numerical analysis was in agreement with the stresses measured by using the hole-drilling method. The analysis can be applied for evaluating structure characteristics machined with a laser

  8. Corrosion of carbon steel nuclear waste containers in marine sediment

    The report describes a study of the corrosion of carbon steel nuclear waste containers in deep ocean sediments, which had the objective of estimating the metal allowance needed to ensure that the containers were not breached by corrosion for 1000 years. It was concluded that under such disposal conditions carbon steel would not be subject to localised corrosion or hydrogen embrittlement, and therefore the study concentrated on evaluating the rate of general attack. This was carried out by developing a mechanistically based mathematical model which was formulated on the conservative assumption that the corrosion would be under activation control, and would not be impeded by the formation of corrosion product layers. This model predicted that an allowance of 33 mm would be required for a 1000 year life. (author)

  9. Ten years of Toarcian argillite - carbon steel in situ interaction

    Dauzeres, Alexandre [IRSN, PRP-DGE/SRTG/LETIS, BP 17, 92262 Fontenay-aux-Roses cedex (France); Maillet, Anais [IRSN, PRP-DGE/SRTG/LETIS, BP 17, 92262 Fontenay-aux-Roses cedex (France); UMR CNRS 7285, IC2MP, Batiment B35 - 5, avenue Albert Turpain, 86022 Poitiers cedex (France); Gaudin, Anne [UMR CNRS 6112, LPGN, 2 rue de la Houssiniere, BP 92208, 44322 Nantes cedex 3 (France); El Albani, Abderrazak; Vieillard, Philippe [UMR CNRS 7285, IC2MP, Batiment B35 - 5, avenue Albert Turpain, 86022 Poitiers cedex (France)

    2013-07-01

    In situ interaction experiments over periods of 2, 6, and 10 years between Toarcian argillite and carbon steel discs were carried out in the Tournemire Underground Research Laboratory (URL), yielding a dataset of the materials' geochemical evolution under conditions representative of the future geological disposal of high-level long-lived radioactive wastes. The carbon steel discs were exposed to corrosion due to trapped oxygen. The corrosion rates indicate that the oxidizing transient lasted between 2 and 6 years. A systematic dissolution of calcium phases (Ca-smectite sheets in I/S and calcite) was observed in the iron diffusion halos. The iron release induced mineralogical dissolution and precipitation reactions, which partly clogged the argillite porosity. (authors)

  10. The kinetics of pitting corrosion of carbon steel

    This report describes progress between April 1986 and May 1987 in a programme studying the kinetics of pitting corrosion in carbon steel containers for the disposal of high level nuclear waste in a granitic repository. Experimental studies are being undertaken with the following objectives: (a) To improve the validation of a mathematical model for the propagation of pitting corrosion. (b) To develop an improved statistical method for analysing experimental pit growth data to take account of the difference in area of laboratory specimens and full size waste containers. (c) To estimate the maximum period during which pitting attack is feasible under repository conditions by calculating the time during which the diffusion of oxygen to the containers will be sufficient to maintain carbon steel in its passive state. Work in the first 14 months of the project has concentrated on (b) and to a lesser extent on (c). (orig./MM)

  11. Ultra-Fine Grained High Carbon Steel by Innovative Deformation

    A.W.F. Smith, D.N. Crowther, P.J. Apps, and P.B. Prangnell

    2007-01-01

    It is well known that the refinement of grain size in metals leads to a significantimprovement in specific mechanical properties. Processing schedules have been investigated aimedat producing an homogeneous ultra-fine ferrite and spheroidised carbide aggregate microstructure in high carbon (CMn) steels (0.6-1.2wt%C), via conventional ???warm??? rolling and innovative Equal Channel Angular Extrusion (ECAE). Suitable deformation schedules were determined from dilatometry and thermo-mechanical G...

  12. Mixed structures in continuously cooled low-carbon automotive steels

    Khalid, F.; Edmonds, D.

    1993-01-01

    Mixed microstructures have been studied in low- carbon microalloyed steels suitable for automotive applications, after continuous cooling from the hot-rolled condition. Microstructural features such as polygonal ferrite, bainitic and acicular ferrite and microphase constituent are identified using transmission electron microscopy. The influence of these mixed structures on the tensile strength, impact toughness and fracture behaviour is examined. It is found that improvements in impact toughn...

  13. Fretting damage of high carbon chromium bearing steel

    Kuno, Masato

    1988-01-01

    This thesis consists of four sections, the fretting wear properties of high carbon chromium bearing steel; the effect of debris during fretting wear; an introduction of a new fretting wear test apparatus used in this study; and the effects of fretting damage parameters on rolling bearings. The tests were operated under unlubricated conditions. Using a crossed cylinder contact arrangement, the tests were carried out with the normal load of 3N, slip amplitude of 50µm, and frequency of 30Hz ...

  14. Analysis of corrosion products of carbon steel in wet bentonite

    As a part of evaluation of the long-term durability for the overpack containers for high-level radioactive waste, we have conducted corrosion tests for carbon steel in wet bentonite, a candidate buffer material. The corrosion rates were evaluated by weight difference of carbon steel and corrosion products were analyzed by Fourier transform infrared spectroscopy (FT-IR) and colorimetry. At 40degC, the corrosion rate of carbon steel in wet bentonite was smaller than that in pure water. At 95degC, however, the corrosion rate in wet bentonite was much higher than that in pure water. This high corrosion rate in wet bentonite at 95degC was considered to result from evaporation of moisture in bentonite in contact with the metal. This evaporation led to dryness and then to shrinkage of the bentonite, which generated ununiform contact of the metal with bentonite. Probably, this ununiform contact promoted the local corrosion. The locally corroded parts of specimen in wet bentonite at 95degC were analyzed by Fourier transform infrared microspectroscopy (micro-FT-IR), and lepidocrocite γ-FeO(OH) was found as well as goethite α-FeO(OH). In wet bentonite at 95degC, hematite α-Fe2O3 was identified by means of colorimetry. (author)

  15. The diffusion of carbon from liquid sodium into stainless steel

    A theory which describes the diffusion of carbon from liquid sodium into austenitic stainless steels is proposed. It is suggested that diffusion occurs simultaneously along two routes, i.e. the grain boundaries and the grains themselves. The grain boundaries provide a faster route than through the grains. In both routes the diffusion is accompanied by precipitation of iron/chromium carbides. The contributions of each route to the carbon concentration in the steel add together to give the observed profile. Each contribution obeys an equation of the error function type given as a solution to Fick's second law. A method of fitting such an equation to suitable curves using the minimising of sums of squares has been developed. It's application to profiles obtained in the present work has shown them to obey the above theory. The contributions from the two routes could be separated and used to evaluate effective diffusion coefficients. Most of the profiles were obtained from steel samples carburised in small sealed capsules. Constant carbon activities in sodium were ensured by the use of suitable sources, mainly couples consisting of a metal and one of its carbides or two carbides of the same metal. The profiles were mainly obtained from the metal by Glow Discharge Optical Spectroscopy. Work on samples obtained from two flowing sodium loops is reported, and are compared with other profiling techniques. (author)

  16. Influence of carbon steel grade on the initial attachment of bacteria and microbiologically influenced corrosion.

    Javed, M A; Neil, W C; Stoddart, P R; Wade, S A

    2016-01-01

    The influence of the composition and microstructure of different carbon steel grades on the initial attachment (≤ 60 min) of Escherichia coli and subsequent longer term (28 days) corrosion was investigated. The initial bacterial attachment increased with time on all grades of carbon steel. However, the rate and magnitude of bacterial attachment varied on the different steel grades and was significantly less on the steels with a higher pearlite phase content. The observed variations in the number of bacterial cells attached across different steel grades were significantly reduced by applying a fixed potential to the steel samples. Longer term immersion studies showed similar levels of biofilm formation on the surface of the different grades of carbon steel. The measured corrosion rates were significantly higher in biotic conditions compared to abiotic conditions and were found to be positively correlated with the pearlite phase content of the different grades of carbon steel coupons. PMID:26785935

  17. 78 FR 64473 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Final No...

    2013-10-29

    ... (``HSLA'') steels, and the substrate for motor lamination steels. IF steels are recognized as low carbon... columbium), or both, added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels... Results of 2011-2012 Antidumping Duty Administrative Review, 78 FR 42039 (July 15, 2013)...

  18. Extraction and determination of microgram amounts of molybdenum (VI) and tungsten (VI) in carbon steel, mild steel, plain steel and Mn-Mo steel

    A method is proposed for the extraction of microgram amounts of molybdenum(VI) and tungsten(VI) from halide medium using tris(2-ethylhexyl) phosphate dissolved in toluene as an extractant. Various experimental parameters involved in the use of the method such as acid concentration, period of equilibration, nature of stripping agents and interference by diverse ions have been studied. The logD-logC plot is used to ascertain probable extractable species. The method has been applied for separation of molybdenum(VI) and tungsten(VI) in alloys like carbon steel, mild steel, plain steel and Mn-Mo steel. The analysis requires 15-20 min. (author). 9 refs., 1 tab

  19. Studies of the properties of heat treated rolled medium carbon steel

    Daramola O. Oluyemi; Oladele Isiaka Oluwole; B.O Adewuyi

    2011-01-01

    Investigations were carried out to study critically the effects of heat treatment on the properties of rolled medium carbon steel. Representative samples of as-rolled medium carbon steel were subjected to heat treatment processes which are; Quenching, Lamellae Formation and Tempering in the following order (Q + Q + L + T), (Q + L + T) and (L + T). The steel was heated to the austenizing temperature of 830 ºC and water quenched. The quenched steel was subjected to lamellae formation by reheati...

  20. Radiofrequency cold plasma nitrided carbon steel: Microstructural and micromechanical characterizations

    Highlights: → C38 carbon steel samples were plasma nitrided using a radiofrequency (rf) nitrogen plasma discharge. → RF plasma treatment enables nitriding for non-heated substrates. → The morphological and chemical analyses show the formation of a uniform thickness on the surface of the nitrided C38 steel. → Nitrogen plasma active species diffuse into the samples and lead to the formation of FexN. → The increase in microhardness values for nitrided samples with plasma processing time is interpreted by the formation of a thicker nitrided layer on the steel surface. - Abstract: In this work, C38 carbon steel was plasma nitrided using a radiofrequency (rf) nitrogen plasma discharge on non-heated substrates. General characterizations were performed to compare the chemical compositions, the microstructures and hardness of the untreated and plasma treated surfaces. The plasma nitriding was carried out on non-heated substrates at a pressure of 16.8 Pa, using N2 gas. Surface characterizations before and after N2 plasma treatment were performed by means of the electron probe microanalysis (EPMA), X-ray photoelectron spectroscopy (XPS) and Vickers microhardness measurements. The morphological and chemical analysis showed the formation of a uniform structure on the surface of the nitrided sample with enrichment in nitrogen when compared to untreated sample. The thickness of the nitride layer formed depends on the treatment time duration and is approximately 14 μm for 10 h of plasma treatment. XPS was employed to obtain chemical-state information of the plasma nitrided steel surfaces. The micromechanical results show that the surface microhardness increases as the plasma-processing time increases to reach, 1487 HV0.005 at a plasma processing time of 8 h.

  1. 75 FR 64700 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Preliminary Results of...

    2010-10-20

    ...'')) steels, high strength low alloy (``HSLA'') steels, and the substrate for motor lamination steels. IF... niobium added to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels with micro...-Quality Steel Products from Brazil, 64 FR 38797 (July 19, 1999); see also Final Affirmative...

  2. Diagrams of supercooled austenite transformations of low-carbon and medium-carbon TRIP-steels

    A. Grajcar

    2008-07-01

    Full Text Available Purpose: The aim of the paper is to determine the influence of cooling conditions on a structure and a shape of CCT-diagrams of TRIP-aided steels.Design/methodology/approach: The diagrams of undeformed supercooled austenite transformations for low-carbon and medium-carbon steels were determined. The specimens were austenitized at a temperature of 1100°C and cooled from a temperature of 900°C with a rate in a range from 1 to 300°Cs-1. The dilatometric tests were carried out by the use of the DIL805A/D dilatometer with a LVDT-type measuring head.Findings: It was found that obtained CCT-diagrams of low-carbon and medium-carbon steels are favourable for manufacturing TRIP-type steels with multiphase structures. The steels are characterized by large ferritic and bainitic fields and a right-displaced pearlitic range. However, a ferrite fraction obtained after cooling with an optimum rate from a temperature of 900°C is low. Increasing the fraction of the α phase requires two-stage cooling after austenitizing.Research limitations/implications: To obtain the optimum ferrite fraction, it is necessary to modify a cooling course in a range of γ→α transformation. It should result in an effective utilization of the time for the transformation of austenite into the fine-grained ferrite.Practical implications: The obtained diagrams of supercooled austenite transformations can be useful in a determination of a cooling course from a finishing rolling temperature for sheets with a multiphase structure.Originality/value: The diagrams of the undeformed supercooled austenite for the low-carbon and medium-carbon steels containing Nb and Ti microadditions were obtained.

  3. 76 FR 16607 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Partial Rescission of Antidumping...

    2011-03-24

    ... merchandise subject to this order is certain hot-rolled products of carbon steel and alloy steel, in coils, of... International Trade Administration Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Partial... antidumping duty order on carbon and certain alloy steel wire rod from Mexico. See Antidumping...

  4. 75 FR 8650 - Carbon and Certain Alloy Steel Wire Rod from Trinidad and Tobago; Final Results of Antidumping...

    2010-02-25

    ... this order is certain hot-rolled products of carbon steel and alloy steel, in coils, of approximately... International Trade Administration (A-274-804) Carbon and Certain Alloy Steel Wire Rod from Trinidad and Tobago... of the antidumping duty order on carbon and certain alloy steel wire rod from Trinidad and...

  5. 77 FR 13545 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Final Results of Antidumping Duty...

    2012-03-07

    ... Changed Circumstances Review: Carbon and Certain Alloy Steel Wire Rod from Mexico, 76 FR 45509 (July 29... order is certain hot-rolled products of carbon steel and alloy steel, in coils, of approximately round... International Trade Administration Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Final...

  6. Corrosion behavior of carbon steel in wet Na-bentonite medium

    Corrosion behaviors of carbon steel in wet Na-bentonite medium were studied. Corrosion rate of carbon steel in wet bentonite was measured to be 20 μm/yr at 25 deg C using the AC impedance technique. This value is agreed with that obtained by weight loss at 40 deg C for 1 year. The effect of bicarbonate ion on the corrosion of carbon steel in wet bentonite was also evaluated. The carbon steels in wet bentonite having 0.001, 0.01, and 0.1 M concentration of bicarbonate ion gave corrosion rates of 20, 8, and 0.2 μm/yr, respectively. Corrosion potentials of specimens were also measured and compared with the AC impedance results. Both results indicated that bicarbonate ion could effectively reduce the corrosion rate of carbon steels in bentonite due to the formation of protective layer on the carbon steel. (author)

  7. Effect of carbon content on the mechanical properties of 10Cr-5W ferritic steels

    The effect of carbon content on the microstructures, the tensile strength, creep strength and fracture toughness of 10Cr-5W ferritic steels containing from 0.02 to 0.13 mass% C is investigated. The low carbon steels possess the higher Ms temperature than the high carbon steels, so that the packet size of the martensite structure is larger in the low carbon steels. Both the FATT (fracture appearance transition temperature) and the USE (upper shelf energy) increase with decreasing carbon content. This means the decrease of toughness and the increase of ductility with decreasing carbon content. Fine precipitates of the Laves phase are observed in the martensite lath in all experimental steels after quality heat treatment. The tensile strength measured at 873 K has a tendency to increase with decreasing C content. But a certain amount of C is needed even in 5 W ferritic steels to keep the longer creep-rupture life under the lower stress level. (orig.)

  8. Boriding of high carbon high chromium cold work tool steel

    High-carbon high-chromium cold work tool steels are widely used for blanking and cold forming of punches and dies. It is always advantageous to obtain an increased wear resistant surface to improve life and performance of these steels. In this connection boriding of a high-carbon high-chromium cold work die steel, D3, was conducted in a mixture of 30 percentage B4C, 70 percentage borax at 950 degree C for two, four and six hours. Case depth of the borided layer obtained was between 40 to 80 micro m. After boriding, the surface hardness achieved was between 1430 to 1544 HV depending upon the process time. X-ray diffraction studies confirmed the formation of a duplex compound layer consisting of FeB and Fe2B. It is generally considered that FeB is undesirable because of its inherent brittleness. Post boriding treatment (homogenization) transformed the compound layer into single-phase layer of Fe2B, while surface hardness decreased to 1345-1430 HV. Pin-on-disc were test showed that wear resistance of the borided samples was superior as compared to non-borided material and increased with boriding time. (author)

  9. Boriding of high carbon high chromium cold work tool steel

    Muhammad, W.

    2014-06-01

    High-carbon high-chromium cold work tool steels are widely used for blanking and cold forming of punches and dies. It is always advantageous to obtain an increased wear resistant surface to improve life and performance of these steels. In this connection boriding of a high-carbon high-chromium cold work die steel, D3, was conducted in a mixture of 30% B4C, 70% borax at 950 °C for two, four and six hours. Case depth of the borided layer obtained was between 40 to 80 μm. After boriding, the surface hardness achieved was between 1430 to 1544 HV depending upon the process time. X-ray diffraction studies confirmed the formation of a duplex compound layer consisting of FeB and Fe2B. It is generally considered that FeB is undesirable because of its inherent brittleness. Post boriding treatment (homogenization) transformed the compound layer into single-phase layer of Fe2B, while surface hardness decreased to 1345-1430 HV. Pin-on-disc wer test showed that wear resistance of the borided samples was superior as compared to non-borided material and increased with boriding time.

  10. Accelerated carbonation of steel slags in a landfill cover construction

    Steel slags from high-alloyed tool steel production were used in a full scale cover construction of a municipal solid waste (MSW) landfill. In order to study the long-term stability of the steel slags within the final cover, a laboratory experiment was performed. The effect on the ageing process, due to i.e. carbonation, exerted by five different factors resembling both the material characteristics and the environmental conditions is investigated. Leaching behaviour, acid neutralization capacity and mineralogy (evaluated by means of X-ray diffraction, XRD, and thermogravimetry/differential thermal analysis, TG/DTA) are tested after different periods of ageing under different conditions. Samples aged for 3 and 10 months were evaluated in this paper. Multivariate data analysis was used for data evaluation. The results indicate that among the investigated factors, ageing time and carbon dioxide content of the atmosphere were able to exert the most relevant effect. However, further investigations are required in order to clarify the role of the temperature.

  11. Boriding of high carbon high chromium cold work tool steel

    High-carbon high-chromium cold work tool steels are widely used for blanking and cold forming of punches and dies. It is always advantageous to obtain an increased wear resistant surface to improve life and performance of these steels. In this connection boriding of a high-carbon high-chromium cold work die steel, D3, was conducted in a mixture of 30% B4C, 70% borax at 950 °C for two, four and six hours. Case depth of the borided layer obtained was between 40 to 80 μm. After boriding, the surface hardness achieved was between 1430 to 1544 HV depending upon the process time. X-ray diffraction studies confirmed the formation of a duplex compound layer consisting of FeB and Fe2B. It is generally considered that FeB is undesirable because of its inherent brittleness. Post boriding treatment (homogenization) transformed the compound layer into single-phase layer of Fe2B, while surface hardness decreased to 1345-1430 HV. Pin-on-disc wer test showed that wear resistance of the borided samples was superior as compared to non-borided material and increased with boriding time

  12. Characterization of Bainitic Microstrucutres in Low Carbon Hsla Steels

    Kang, Ju Seok; Park, Chan Gyung

    The austenite phase of low carbon steels can be transformed to various bainitic microstructures such as granular bainite, acicular ferrite and bainitic ferrite during continuous cooling process. In the present study site-specific transmission electron microscope (TEM) specimens were prepared by using focused ion beam (FIB) to identify the bainitic microstructure in low carbon high strength low alloy (HSLA) steels clearly. Granular bainite was composed of fine subgrains and 2nd phase constituents like M/A or pearlite located at grain and/or subgrain boundaries. Acicular ferrite was identified as an aggregate of randomly orientated needle-shaped grains. The high angle relations among acicular ferrite grains were thought to be caused by intra-granular nucleation, which could be occur under the high cooling rate condition. Bainitic ferrite revealed uniform and parallel lath structure within the packet. In some case, however, the parallel lathes showed high angle relations due to packet overlapping during grow of bainitic ferrite, resulting in high toughness properties in bainitic ferrite based steels.

  13. Acid neutralisation capacity of accelerated carbonated stainless steel slag.

    Johnson, D C; MacLeod, C L; Hills, C D

    2003-05-01

    The acid neutralisation capacity test is widely used to assess the long-term performance of waste materials prior to disposal. Samples of fixed mass are exposed to increasing additions of nitric add in sealed containers and the resultant pH is plotted as a titration curve. In this work, the add neutralisation capacity test was used in the assessment of an accelerated carbonated stainless steel slag. Difficulties arose in applying the test procedure to this material. This was largely because of the raised pressure from significant volumes of released carbon dioxide trapped in the sealed sample containers, causing an alteration to leachate pH values. Consequently, the add neutralisation capacity test was modified to enable testing of samples in equilibrium with the atmosphere. No adverse effects on the results from testing of a carbonate free material were recorded. PMID:12803247

  14. Inhibition Effect of Dodecylamine on Carbon Steel Corrosion in Hydrochloric Acid Solution

    Chen, Zhenyu; Huang, Ling; Qiu, Yubing; Guo, Xingpeng

    2012-12-01

    Dodecylamine spontaneously adsorbs on carbon steel via its polar group (-NH2) in hydrochloric acid solution. Furthermore, it forms a monolayer film on carbon steel surface. The inhibition mechanism of dodecylamine for carbon steel is geometric blocking effect. The adsorption of dodecylamine on carbon steel surface follows Arrhenius equation. The adsorption slightly increases activated energy, but greatly reduces pre-exponential factor value. Atomic force microscopy force curves indicate that at the area without adsorbed dodecylamine, no obvious adhere force occurs. At the area with adsorbed dodecylamine, however, an average 1.3 nN adhere force is observed.

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

    2002-01-01

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

  16. Mechanical properties of high manganese non-magnetic steel and carbon steel welded butt joints. 1. Investigation for applying dissimilar materials to steel structures

    Mechanical properties of the dissimilar materials welded butt joints between high manganese non-magnetic steels and carbon steels (referred to as DMW joints) were investigated for applying to steel structures. The SS400 is used as the carbon steel. The DMW joints, in which weld defects such as an incomplete penetration, blowhole and crack were not found, were shown to be of good quality. The tensile strength in the DMW joints was 10 (%) higher than that of the carbon steel. In the bend tests, the DMW joints showed good ductility, without cracks. The Charpy absorbed energy at 0 (degC) of the DMW joints was over 120 (J) at the bond where it seems to be the lowest. Significant hardening or softening was not detected in the heat affected zone. (author)

  17. A Spray Pyrolysis Method to Grow Carbon Nanotubes on Carbon Fibres, Steel and Ceramic Bricks.

    Vilatela, Juan J; Rabanal, M E; Cervantes-Sodi, Felipe; García-Ruiz, Máximo; Jiménez-Rodríguez, José A; Reiband, Gerd; Terrones, Mauricio

    2015-04-01

    We demonstrate a spray pyrolysis method to grow carbon nanotubes (CNTs) with high degree of crystallinity, aspect ratio and degree of alignment on a variety of different substrates, such as conventional steel, carbon fibres (CF) and ceramics. The process consists in the chemical vapour deposition of both a thin SiO2 layer and CNTs that subsequently grow on this thin layer. After CNT growth, increases in specific surface by factors of 1000 and 30 for the steel and CF samples, respectively, are observed. CNTs growth on ceramic surfaces results in a surface resistance of 37.5 Ohm/sq. When using conventional steel as a rector tube, we observed CNTs growth rates of 0.6 g/min. Details of nanotube morphology and the growth mechanism are discussed. Since the method discussed here is highly versatile, it opens up a wide variety of applications in which specific substrates could be used in combination with CNTs. PMID:26353505

  18. INFLUENCE OF ELECTRIC SPARK ON HARDNESS OF CARBON STEEL

    I. O. Vakulenko

    2014-03-01

    Full Text Available Purpose. The purpose of work is an estimation of influence of an electric spark treatment on the state of mouldable superficial coverage of carbon steel. Methodology. The steel of fragment of railway wheel rim served as material for research with chemical composition 0.65% С, 0.67% Mn, 0.3% Si, 0.027% P, 0.028% S. Structural researches were conducted with the use of light microscopy and methods of quantitative metallography. The structural state of the probed steel corresponded to the state after hot plastic deformation. The analysis of hardness distribution in the micro volumes of cathode metal was carried out with the use of microhardness tester of type of PMT-3. An electric spark treatment of carbon steel surface was executed with the use of equipment type of EFI-25M. Findings. After electric spark treatment of specimen surface from carbon steel the forming of multi-layered coverage was observed. The analysis of microstructure found out the existence of high-quality distinctions in the internal structure of coverage metal, depending on the probed area. The results obtained in the process are confirmed by the well-known theses, that forming of superficial coverage according to technology of electric spark is determined by the terms of transfer and crystallization of metal. The gradient of structures on the coverage thickness largely depends on development of structural transformation processes similar to the thermal character influence. Originality. As a result of electric spark treatment on the condition of identical metal of anode and cathode, the first formed layer of coverage corresponds to the monophase state according to external signs. In the volume of coverage metal, the appearance of carbide phase particles is accompanied by the decrease of microhardness values. Practical value. Forming of multi-layered superficial coverage during electric spark treatment is accompanied by the origin of structure gradient on a thickness. The effect

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

    Mohamed Mahdy

    2013-01-01

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

  20. Welded, sandblasted, stainless steel corrugated bars in non-carbonated and carbonated mortars: A 9-year corrosion study

    Bautista, A.; Paredes, E. C.; Álvarez, S. M.; Velasco, F.

    2016-01-01

    Three different stainless steel corrugated grades (UNS S20430, S30403 and S32205) were similar welded to stainless steel bars with the same composition and dissimilar welded to carbon steel (CS). After cleaning the welding oxides by sandblasting, the reinforcements were embedded in mortar with chlorides and some of the samples were carbonated. Corrosion activity was monitored using corrosion potential (Ecorr) and electrochemical impedance spectroscopy (EIS). After 8 years of exposure, the sam...

  1. Effect of heat treatment on carbon steel pipe welds

    The heat treatment to improve the altered properties of carbon steel pipe welds is described. Pipe critical components in oil, gasification and nuclear reactor plants require adequate room temperature toughness and high strength at both room and moderately elevated temperatures. Microstructure and microhardness across the welds were changed markedly by the welding process and heat treatment. The presentation of hardness fluctuation in the welds can produce premature failure. A number of heat treatments are suggested to improve the properties of the welds. (author) 8 figs., 5 refs

  2. Friction stir processing on high carbon steel U12

    Tarasov, S. Yu., E-mail: tsy@ispms.ru; Rubtsov, V. E., E-mail: rvy@ispms.ru [Institute of Strength Physics and Materials Science SB RAS, Tomsk, 634055 (Russian Federation); National Research Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation); Melnikov, A. G., E-mail: melnikov-ag@tpu.ru [National Research Tomsk Polytechnic University, Tomsk, 634050 (Russian Federation)

    2015-10-27

    Friction stir processing (FSP) of high carbon steel (U12) samples has been carried out using a milling machine and tools made of cemented tungsten carbide. The FSP tool has been made in the shape of 5×5×1.5 mm. The microstructural characterization of obtained stir zone and heat affected zone has been carried out. Microhardness at the level of 700 MPa has been obtained in the stir zone with microstructure consisting of large grains and cementitte network. This high-level of microhardness is explained by bainitic reaction developing from decarburization of austenitic grains during cementite network formation.

  3. Corrosion inhibition of carbon steel by extract of Buddleia perfoliata

    ROY LOPES-SESENES

    2012-06-01

    Full Text Available Buddleia perfoliata leaves extract has been investigated as a carbon steel corrosion inhibitor in 0.5 M sulfuric acid by using polarization curves, electrochemical impedance spectroscopy and weight-loss tests at different concentrations (0, 100, 200, 300, 400 and 500 ppm and temperatures, namely 25, 40 and 60 °C. Results showthat inhibition efficiency increases as the inhibitor concentration increases, decreases with temperature, and reaches a maximum value after 12 h of exposure, decreasing with a further increase in the exposure time. It was found that the inhibitory effect is due to the presence of tannines on this extract.

  4. Corrosion Inhibition of Carbon Steel in Chloride and Sulfate Solutions

    Amr Ahmed Elsayed

    2016-02-01

    Full Text Available Corrosion is a major problem in industry and in infrastructure; a huge sum of expenditure every year is spent on preventing, retarding, and repairing its damages. This work studies the engineering of an inhibitor for carbon steel metal used in the cooling systems containing high concentration of chloride and sulfate ions. For this purpose, the synergy between the dichromate, molybdate and nitrite inhibitors is examined and optimized to the best results. Moreover, care was taken that the proposed inhibitor is compliant with the environmental laws and regulations.

  5. Friction stir processing on high carbon steel U12

    Friction stir processing (FSP) of high carbon steel (U12) samples has been carried out using a milling machine and tools made of cemented tungsten carbide. The FSP tool has been made in the shape of 5×5×1.5 mm. The microstructural characterization of obtained stir zone and heat affected zone has been carried out. Microhardness at the level of 700 MPa has been obtained in the stir zone with microstructure consisting of large grains and cementitte network. This high-level of microhardness is explained by bainitic reaction developing from decarburization of austenitic grains during cementite network formation

  6. Hybrid Friction Stir Welding of High-carbon Steel

    Don-Hyun Choi; Seung-Boo Jung; Chang-Yong Lee; Byung-Wook Ahn; Jung-Hyun Choi; Yun-Mo Yeon; Keun Song; Seung-Gab Hong; Won-Bae Lee; Ki-Bong Kang

    2011-01-01

    A high-carbon steel joint, SK5 (0.84 wt% C), was successfully welded by friction stir welding (FSW), both without and with a gas torch, in order to control the cooling rate during welding. After welding, the weld zone comprised gray and black regions, corresponding to microstructural variation: a martensite structure and a duplex structure of ferrite and cementite, respectively. The volume fraction of the martensite structure and the Vickers hardness in the welds were decreased with the using of the gas torch, which was related with the lower cooling rate.

  7. Austenite decomposition in carbon steel under dynamic deformation conditions

    A. Nowotnik

    2007-01-01

    Full Text Available Purpose: The main purpose of this paper was to estimate the effect of the dynamic conditions resulting fromdeformation process on the austenite decomposition into ferrite and pearlite (A→F+P in the commercial carbon steel.Design/methodology/approach: In the paper flow stress curves and microstructure of deformed steel within therange of discontinuous (austenite to pearlite and austenite to ferrite transformation at different strain rates andcooling rates were presented. The microstructure of hot deformed samples was tested by means of an opticaland electron microscopy.Findings: It was shown that the flow localization during hot deformation and preferred growth of the pearlitecolonies at shear bands was very limited. The most characteristic feature of the microstructure observed for hotdeformed samples was the development of carbides that nucleated along elongated ferrite grains.Research limitations/implications: In spite of intense strain hardening due to deformation and phasetransformation overlapping, microstructural observation of deformed samples did not reveal significant flowlocalization effects or heterogeneous distribution of the eutectoid components. Therefore, complementary testsshould be carried out on the steel with higher strain above the 0.5 value.Originality/value: There was no data referred to particular features of the dynamic processes, such as dynamicrecrystallization and recovery, dynamic precipitation, that can occur during austenite decomposition into ferrite,and especially during discontinuous transformation of austenite to pearlite.

  8. Hydrogen attack - Influence of hydrogen sulfide. [on carbon steel

    Eliezer, D.; Nelson, H. G.

    1978-01-01

    An experimental study is conducted on 12.5-mm-thick SAE 1020 steel (plain carbon steel) plate to assess hydrogen attack at room temperature after specimen exposure at 525 C to hydrogen and a blend of hydrogen sulfide and hydrogen at a pressure of 3.5 MN/sq m for exposure times up to 240 hr. The results are discussed in terms of tensile properties, fissure formation, and surface scales. It is shown that hydrogen attack from a high-purity hydrogen environment is severe, with the formation of numerous methane fissures and bubbles along with a significant reduction in the room-temperature tensile yield and ultimate strengths. However, no hydrogen attack is observed in the hydrogen/hydrogen sulfide blend environment, i.e. no fissure or bubble formation occurred and the room-temperature tensile properties remained unchanged. It is suggested that the observed porous discontinuous scale of FeS acts as a barrier to hydrogen entry, thus reducing its effective equilibrium solubility in the iron lattice. Therefore, hydrogen attack should not occur in pressure-vessel steels used in many coal gasification processes.

  9. Corrosion Behavior of Carbon Steels in CCTS Environment

    M. Cabrini

    2016-01-01

    Full Text Available The paper reports the results of an experimental work on the effect of steel microstructures on morphology and protectiveness of the corrosion scale formed in water saturated by supercritical CO2. Two HSLA steels were tested. The microstructures were modified by means of different heat treatments. Weight loss was measured after exposure at CO2 partial pressure of 80 bar and 60°C temperature. The morphology of the scale was analyzed by means of scanning electron microscope (SEM energy-dispersive X-ray spectroscopy (EDX. Cathodic potentiodynamic tests were carried out on precorroded specimens for evaluating the effect of preformed scales on cathodic polarization curves in CO2 saturated sulphuric acid solution at pH 3, which is the value estimated for water saturated by supercritical CO2. The results are discussed in order to evaluate the effect of iron carbide network on scale growth and corrosion rate. Weight loss tests evidenced average corrosion rate values in the range 1–2.5 mm/y after 150-hour exposure. The presence of thick siderite scale significantly reduces the corrosion rate of carbon steel. A slight decrease of the corrosion rate was observed as the scale thickness increases and moving from martensite to microstructures containing carbides.

  10. Carbon distribution in the martensite structure of structural steel

    Gundyrev, V. M.; Zel'dovich, V. I.; Schastlivtsev, V. M.

    2016-05-01

    The martensite structure of a hardened pseudosingle crystal of grade 37KhN3A medium-carbon structural steel (0.37 wt % C, 1.50 Cr, 3.0 Ni, 0.33 Mn) had the form of coarse packets with dimensions of to 1 cm in the cross section. Every packet was composed of six-orientation martensite crystals arising on one common austenite plane of type {111}. The position of three texture maximums was determined using an X-ray diffractometer for every orientation. In addition, the position of four maximums of retained austenite was found. The periods of martensite lattices and retained austenite as well as the carbon concentration in martensite lattices and near the boundaries are determined.

  11. Study on microstructure and mechanical characteristics of low-carbon steel and ferritic stainless steel joints

    In this work, examinations on the microstructure and mechanical properties of plain carbon steel and AISI 430 ferritic stainless steel dissimilar welds are carried out. Welding is conducted in both autogenous and using ER309L austenitic filler rod conditions through gas tungsten arc welding process. The results indicate that fully-ferritic and duplex ferritic–martensitic microstructures are formed for autogenous and filler-added welds, respectively. Carbide precipitation and formation of martensite at ferrite grain boundaries (intergranular martensite) as well as grain growth occur in the heat affected zone (HAZ) of AISI 430 steel. It is found that weld heat input can strongly affect grain growth phenomenon along with the amount and the composition of carbides and intergranular martensite. Acquired mechanical characteristics of weld in the case of using filler metal are significantly higher than those of autogenous one. Accordingly, ultimate tensile strength (UTS), hardness, and absorbed energy during tensile test of weld metal are increased from 662 MPa to 910 MPa, 140 Hv to 385 Hv, and 53.6 J m−3 to 79 J m−3, respectively by filler metal addition. From fracture surfaces, predominantly ductile fracture is observed in the specimen welded with filler metal while mainly cleavage fracture occurs in the autogenous weld metal

  12. Study on microstructure and mechanical characteristics of low-carbon steel and ferritic stainless steel joints

    Sarkari Khorrami, Mahmoud; Mostafaei, Mohammad Ali; Pouraliakbar, Hesam, E-mail: hpouraliakbar@alum.sharif.edu; Kokabi, Amir Hossein

    2014-07-01

    In this work, examinations on the microstructure and mechanical properties of plain carbon steel and AISI 430 ferritic stainless steel dissimilar welds are carried out. Welding is conducted in both autogenous and using ER309L austenitic filler rod conditions through gas tungsten arc welding process. The results indicate that fully-ferritic and duplex ferritic–martensitic microstructures are formed for autogenous and filler-added welds, respectively. Carbide precipitation and formation of martensite at ferrite grain boundaries (intergranular martensite) as well as grain growth occur in the heat affected zone (HAZ) of AISI 430 steel. It is found that weld heat input can strongly affect grain growth phenomenon along with the amount and the composition of carbides and intergranular martensite. Acquired mechanical characteristics of weld in the case of using filler metal are significantly higher than those of autogenous one. Accordingly, ultimate tensile strength (UTS), hardness, and absorbed energy during tensile test of weld metal are increased from 662 MPa to 910 MPa, 140 Hv to 385 Hv, and 53.6 J m{sup −3} to 79 J m{sup −3}, respectively by filler metal addition. From fracture surfaces, predominantly ductile fracture is observed in the specimen welded with filler metal while mainly cleavage fracture occurs in the autogenous weld metal.

  13. AISI/DOE Technology Roadmap Program: Effects of Residuals in Carbon Steels

    George E. Ruddle

    2002-11-25

    AN experimental study of the effects of residual elements in carbon steels was carried out to gain better understanding and control of the effects of residual elements emanating from recycled steel scrap. Two plain carbon steel grade compositions (one medium-carbon and one low-carbon), residual elements and levels, and four areas of study, were selected on the bases of a comprehensive literature survey and consultation with sponsor steel companies. The influence of residuals (Cu, Sn, Ni, P, Si, up to the levels studied here), on these laboratory produced hot rolled steels was studied in the areas of (a) hot ductility, (b) surface hot shortness, (c) scale formation and adherence, and (d) embrittlement and mechanical properties. This report summarizes the experimental procedures, results, discussion and conclusions of this study. The relevance of the study is also discussed in relation to steel processing and product properties and in relation to energy consumption and environmental compliance.

  14. Effect of Cr and Mo on strain ageing behaviour of low carbon steel

    This work explores the effects of Cr (0.26-0.74 wt%) and Mo (0.09-0.3 wt%) additions on the kinetics of strain ageing process in low carbon steel. The strain ageing behaviour of the steels was investigated by using tensile tests and transmission electron microscopy. The results have shown that Mo-alloyed steels undergo the same four stages of ageing as unalloyed low carbon steel, whereas Cr-alloyed steels exhibit only three stages of ageing. At the same time, the addition of Mo accelerates the ageing response, while alloying with Cr reduces the rate of strain ageing by ∼3 times in comparison with non-alloyed low carbon steel. It especially delays the offset of Stage III. This is explained by the reduction of carbon content in ferrite due to the enrichment of cementite with Cr leading to the reduction of its equilibrium solubility in ferrite.

  15. Efficiency of inhibitor for biocorrosion influenced by consortium sulfate reducing bacteria on carbon steel

    Mahat, Nur Akma; Othman, Norinsan Kamil [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Sahrani, Fathul Karim [School of Environment and Natural Resources Science, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2015-09-25

    The inhibition efficiency of benzalkonium chloride (BKC) in controlling biocorrosion on the carbon steel surfaces has been investigated. The carbon steel coupons were incubated in the presence of consortium SRB (C-SRB) with and without BKC for the difference medium concentration. The corrosion rate and inhibition efficiency have been evaluated by a weight loss method. The morphology of biofilm C-SRB on the steel surfaces were characterized with variable pressure scanning electron microscopy (VPSEM). The results revealed that BKC exhibits a low corrosion rate, minimizing the cell growth and biofilm development on the carbon steel surfaces.

  16. Efficiency of inhibitor for biocorrosion influenced by consortium sulfate reducing bacteria on carbon steel

    The inhibition efficiency of benzalkonium chloride (BKC) in controlling biocorrosion on the carbon steel surfaces has been investigated. The carbon steel coupons were incubated in the presence of consortium SRB (C-SRB) with and without BKC for the difference medium concentration. The corrosion rate and inhibition efficiency have been evaluated by a weight loss method. The morphology of biofilm C-SRB on the steel surfaces were characterized with variable pressure scanning electron microscopy (VPSEM). The results revealed that BKC exhibits a low corrosion rate, minimizing the cell growth and biofilm development on the carbon steel surfaces

  17. Efficiency of inhibitor for biocorrosion influenced by consortium sulfate reducing bacteria on carbon steel

    Mahat, Nur Akma; Othman, Norinsan Kamil; Sahrani, Fathul Karim

    2015-09-01

    The inhibition efficiency of benzalkonium chloride (BKC) in controlling biocorrosion on the carbon steel surfaces has been investigated. The carbon steel coupons were incubated in the presence of consortium SRB (C-SRB) with and without BKC for the difference medium concentration. The corrosion rate and inhibition efficiency have been evaluated by a weight loss method. The morphology of biofilm C-SRB on the steel surfaces were characterized with variable pressure scanning electron microscopy (VPSEM). The results revealed that BKC exhibits a low corrosion rate, minimizing the cell growth and biofilm development on the carbon steel surfaces.

  18. Distribution of radionuclides during melting of carbon steel

    Thurber, W.C.; MacKinney, J.

    1997-02-01

    During the melting of steel with radioactive contamination, radionuclides may be distributed among the metal product, the home scrap, the slag, the furnace lining and the off-gas collection system. In addition, some radionuclides will pass through the furnace system and vent to the atmosphere. To estimate radiological impacts of recycling radioactive scrap steel, it is essential to understand how radionuclides are distributed within the furnace system. For example, an isotope of a gaseous element (e.g., radon) will exhaust directly from the furnace system into the atmosphere while a relatively non-volatile element (e.g., manganese) can be distributed among all the other possible media. This distribution of radioactive contaminants is a complex process that can be influenced by numerous chemical and physical factors, including composition of the steel bath, chemistry of the slag, vapor pressure of the particular element of interest, solubility of the element in molten iron, density of the oxide(s), steel melting temperature and melting practice (e.g., furnace type and size, melting time, method of carbon adjustment and method of alloy additions). This paper discusses the distribution of various elements with particular reference to electric arc furnace steelmaking. The first two sections consider the calculation of partition ratios for elements between metal and slag based on thermodynamic considerations. The third section presents laboratory and production measurements of the distribution of various elements among slag, metal, and the off-gas collection system; and the final section provides recommendations for the assumed distribution of each element of interest.

  19. General corrosion of carbon steels in high temperature water

    This short paper seeks to provide a summary of the main knowledge about the general corrosion of carbon steels in high temperature water. In pure water or slightly alkaline deaerated water, steels develop a protective coating of magnetite in a double layer (Potter and Mann oxide) or a single layer (Bloom oxide). The morphology of the oxide layer and the kinetics of corrosion depend on the test parameters controlling the solubility of iron. The parameters exercising the greatest influence are partial hydrogen pressure and mass transfer: hydrogen favours the solubilization of the magnetite; the entrainment of the dissolved iron prevents a redeposition of magnetite on the surface of the steel. Cubic or parabolic in static conditions, the kinetics of corrosion tends to be linear in dynamic conditions. In dynamic operation, corrosion is at least one order of magnitude lower in water with a pH of 10 than in pure water with a pH of 7. The activation energy of corrosion is 130 kJ/mol (31 kcal/mol). This results in the doubling of corrosion at around 300 deg C for a temperature increase of 15 deg C. Present in small quantities (100-200 ppb), oxygen decreases general corrosion but increases the risk of pitting corrosion - even for a low chloride content - and stress corrosion cracking or corrosion-fatigue. The steel composition has probably an influence on the kinetics of corrosion in dynamic conditions; further work would be required to clarify the effect of some residual elements. (author). 31 refs., 9 figs., 2 tabs

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

    Bogucki R.; Pytel S.M.

    2014-01-01

    The results of mechanical properties and microstructure observation of low carbon copper bearing steel with high addition of molybdenum are presented in this paper. This steels were characterized by contents of molybdenum in the range from 1% to 3% wt. After the thermo -mechanical processing the steels were subsequently quenched and tempered at different temperatures (500-800 °C) for 1h. The changes of mechanical properties as function of tempering temperature were typical for the steel with ...

  1. Boric acid corrosion of carbon and low alloy steels

    Leakage of borated water from the reactor coolant system of pressurized water reactors (PWRs) and the resulting corrosion of carbon and low alloy steel components are concerns that have been addressed by utilities for many years. Significant corrosion has been observed in instances where such leakage has gone undetected for several months. In 1990, the B and W Owners Group (B and WOG) sponsored a test program to determine the levels of wastage that are possible when primary water leakage occurs. In this test program, carbon and stainless steel specimens were exposed to borated water at temperatures from 300 F to 550 F. Initial boric acid concentration was controlled within the limits of 13,000 to 15,000 ppm (as H3BO3) with 1.0--2.0 ppm lithium (as LiOH) added to duplicate the primary water chemistry. Testing was performed to determine the degree of attack caused by a leak traveling along a pipe both with and without insulation. These tests show the importance of temperature and boric acid concentrations on the wastage that can occur from such a leak

  2. 75 FR 1495 - Certain Hot-Rolled Carbon Steel Flat Products From India: Preliminary Results of Countervailing...

    2010-01-11

    ... interstitial-free (IF) steels, high-strength low-alloy (HSLA) steels, and the substrate for motor lamination... nitrogen elements. HSLA steels are recognized as steels with micro-alloying levels of elements such as... Countervailing Duty Orders: Certain Hot-Rolled Carbon Steel Flat Products From India and Indonesia, 66 FR...

  3. 77 FR 45576 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Preliminary...

    2012-08-01

    ...-free (``IF'')) steels, high strength low alloy (``HSLA'') steels, and the substrate for motor... and nitrogen elements. HSLA steels are recognized as steels with micro-alloying levels of elements...: Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China, 66 FR 59561...

  4. 75 FR 1031 - Certain Hot-Rolled Carbon Steel Flat Products from India: Notice of Preliminary Results of...

    2010-01-08

    ..., high-strength low-alloy (``HSLA'') steels, and the substrate for motor lamination steels. IF steels are... commonly referred to as columbium), or both, added to stabilize carbon and nitrogen elements. HSLA steels... Alloy Steel Wire Rod from Brazil, 67 FR 55792, 55794-96 (August 30, 2002) (``Wire Rod from...

  5. Coefficient of friction between carbon steel and perlite concrete surfaces. Test report

    The results of coefficient of friction, μ, tests conducted on perlite blocks and carbon steel plates under various conditions are discussed. Variables included in the test entailed the use of lubricants (i.e. water and simulated radioactive waste solution) abrasives (120 grit, 60 grit, 40 grit sand paper) applied to the surfaces of the perlite block and carbon steel plates

  6. 48 CFR 225.7011 - Restriction on carbon, alloy, and armor steel plate.

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Restriction on carbon, alloy, and armor steel plate. 225.7011 Section 225.7011 Federal Acquisition Regulations System DEFENSE... on carbon, alloy, and armor steel plate....

  7. 77 FR 65712 - Circular Welded Carbon-Quality Steel Pipe From Vietnam; Termination of Investigation

    2012-10-30

    ... COMMISSION Circular Welded Carbon-Quality Steel Pipe From Vietnam; Termination of Investigation AGENCY... subsidies in connection with the subject investigation (77 FR 64471). Accordingly, pursuant to section 207... investigation concerning circular welded carbon-quality steel pipe from Vietnam (investigation No....

  8. 75 FR 21658 - Carbon and Certain Alloy Steel Wire Rod From Trinidad and Tobago

    2010-04-26

    ... amended, 67 FR 68036 (Nov. 8, 2002). In accordance with sections 201.16(c) and 207.3 of the Commission's... COMMISSION Carbon and Certain Alloy Steel Wire Rod From Trinidad and Tobago AGENCY: United States... in the antidumping duty Investigation No. 731-TA-961 concerning carbon and certain alloy steel...

  9. 75 FR 44766 - Certain Welded Carbon Steel Standard Pipe from Turkey: Final Results of Countervailing Duty...

    2010-07-29

    ...: Certain Welded Carbon Steel Pipe and Tube Products From Turkey, 51 FR 7984 (March 7, 1986). On April 1...: Preliminary Results of Countervailing Duty Administrative Review, 75 FR 16439 (April 1, 2010) (Preliminary...) was rescinded. See Welded Carbon Steel Standard Pipe and Tube from Turkey: Notice of Rescission...

  10. 77 FR 19623 - Certain Welded Carbon Steel Standard Pipe from Turkey: Preliminary Results of Countervailing Duty...

    2012-04-02

    ... Pipe and Tube Products from Turkey, 51 FR 7984 (March 7, 1986). \\2\\ See Antidumping or Countervailing... Administrative Review, in Part, 76 FR 78886 (December 20, 2011). \\12\\ See Certain Welded Carbon Steel Standare...: Certain Welded Carbon Steel Standard Pipe from Turkey, 72 FR 62837, 62838 (November 7, 2007) (Turkey...

  11. 78 FR 49255 - Certain Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Partial Rescission of...

    2013-08-13

    ... Request for Revocation in Part, 78 FR 38924 (June 28, 2013). On July 25, 2013, Petitioner withdrew its... International Trade Administration Certain Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Partial... certain circular welded carbon steel pipes and tubes from Taiwan. The period of review (POR) is May...

  12. Corrosion-electrochemical behavior of diffusionally chromized carbon steels in aggressive environments

    One generalized the experimental data of many year investigations into corrosion-electrochemical behavior of diffusionally chromized carbon steels (steel 45) depending on diffusion saturation process factors and on composition of saturating powder mixture. One formulated compositions of saturating powder enabling to improve essentially corrosion resistance of treated carbon steels in the aggressive environments. Resistance is improved due to introduction of calcium hydride into saturating mixture

  13. Work-Hardening and Deformation Mechanism of Cold Rolled Low Carbon Steel

    Wang Su-Fen; Peng Yan; Li Zhi-Jie

    2013-01-01

    The study reports the mechanical property and microstructure of cold rolled low carbon steel and its work-hardening behavior in the deformation process. The tensile test in room temperature of low carbon steel was implemented for the different cold rolling deformation, the stress-strain curve was draught according to the relationship between strength and deformation and fitted for the polynomial fitting, the strain hardening exponent (n) of test steel was calculated by the Hollomon method. In...

  14. Microstructure and Properties of Ti and Ti+Nb Ultra-Low-Carbon Bake Hardened Steels

    CHEN Ji-ping; KANG Yong-lin; HAO Ying-min; LIU Guang-ming; XIONG Ai-ming

    2009-01-01

    Hot rolling, cold rolling and continuous annealing processes of Ti bearing and Ti+ Nb stabilized ultra-low-carbon bake hardened steels were experimentally studied. The microstrueture and texture evolution, as well as the morphology, size and distribution of second phase precipitates during hot roiling, cold rolling and continuous annea-ling were also analyzed. The results showed that the size of NbC precipitates in Ti+ Nb stabilized ultra-low-carbon bake hardened steel was smaller than that of TiC precipitates in Ti bearing ultra-low-carbon bake hardened steel, which made the average grain size of Ti+ Nb stabilized ultra-low-carbon bake hardened steel finer than that of Ti bearing ultra-low-carbon bake hardened steel; for the yield strength, the former was higher than the latter; but for the γ value which reflects the deep-drawing performance, the former was lower than the latter.

  15. 75 FR 60814 - Carbon Steel Butt-Weld Pipe Fittings From Brazil, China, Japan, Taiwan, and Thailand

    2010-10-01

    ... Investigation No. F.R. cite 12/17/86 Carbon steel butt- 731-TA-308 51 FR 45152. weld pipe fittings/ Brazil. 12/17/86 Carbon steel butt- 731-TA-310 51 FR 45152. weld pipe fittings/ Taiwan. 2/10/87 Carbon steel butt- 731-TA-309 52 FR 4167. weld pipe fittings/ Japan. 7/6/92 Carbon steel butt- 731-TA-520 57...

  16. Internal corrosion of carbon steel piping in hot aquifers service

    Simičić Miloš V.

    2011-01-01

    Full Text Available Internal corrosion of carbon steel pipelines is a major problem encountered in water service. In terms of prediction of the remaining lifetime for water pipelines based on the corrosion allowance, the three main approaches are corrosion modelling, corrosion inhibitor availability, and corrosion monitoring. In this study we used two theoretical corrosion models, CASSANDRA and NORSOK M-506 of quite different origin in order to predict uniform corrosivity of hot aquifers in eight different pipelines. Because of the varying calculation criteria for the different models, these can give very different corrosion rate predictions for the same data input. This is especially true under conditions where the formation of protective films may occur, such as at elevated temperatures. The evaluation of models was conducted by comparison using weight-loss coupons and three corrosion inhibitors were obtained from commercial suppliers. The tests were performed during the 60-day period. Even though inhibitors’ efficiencies of 98% had been achieved in laboratory testing, inhibitors’ availabilities of 85% have been used due to logistics problems and other issues. The results, given in mmpy, i.e. millimeter per year, are very consistent with NORSOK M-506 prediction. This is presumably because the model considers the effect of the formation of a passive iron carbonate film at temperatures above 80 °C and significant reduction in corrosion rate. Corrosion inhibitor A showed a better performance than inhibitors B and C in all cases but the target corrosion rates of less than 0.1 mmpy were achieved for all inhibitors. The chemical type of corrosion inhibitor A is based on quaternary amines mixed with methanol, isopropyl alcohol, xylene and ethylbenzene. Based on the obtained results the carbon steel lifetime of 30 years, provided proper inhibitors are present and 3mm corrosion allowance, can be achieved for hot aquifers service with presented water compositions.

  17. 75 FR 22372 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's...

    2010-04-28

    ... International Trade Administration Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe... determines that certain seamless carbon and alloy steel standard, line, and pressure pipe from the People's... imports of certain seamless carbon and alloy steel standard, line, and pressure pipe (``seamless...

  18. 75 FR 69050 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's...

    2010-11-10

    ... International Trade Administration Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe... duty order on certain seamless carbon and alloy steel standard, line, and pressure pipe (``seamless... seamless pipe from the PRC. See Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure...

  19. 77 FR 64471 - Circular Welded Carbon-Quality Steel Pipe From the Socialist Republic of Vietnam: Final Negative...

    2012-10-22

    ... International Trade Administration Circular Welded Carbon-Quality Steel Pipe From the Socialist Republic of... welded carbon-quality steel pipe (``circular welded pipe'') from the Socialist Republic of Vietnam... Preliminary Determination.\\1\\ \\1\\ See Circular Welded Carbon-Quality Steel Pipe from the Socialist Republic...

  20. 78 FR 33108 - Circular Welded Carbon-Quality Steel Pipe From China; Institution of Five-Year Reviews

    2013-06-03

    ... countervailing duty orders on imports of circular welded carbon-quality steel pipe from China (73 FR 42545-42549... COMMISSION Circular Welded Carbon-Quality Steel Pipe From China; Institution of Five-Year Reviews AGENCY... welded carbon-quality steel pipe from China would be likely to lead to continuation or recurrence...

  1. 76 FR 24462 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Rescission of...

    2011-05-02

    ... International Trade Administration Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China... antidumping duty order on certain cut-to-length carbon steel plate (``CTL Plate'') from the People's Republic of China (``PRC''). See Suspension Agreement on Certain Cut- to-Length Carbon Steel Plate From...

  2. 77 FR 73674 - Circular Welded Carbon-Quality Steel Pipe From India, Oman, The United Arab Emirates, and Vietnam

    2012-12-11

    ... countervailing duty determination with respect to circular welded carbon-quality steel pipe from Vietnam (77 FR... COMMISSION Circular Welded Carbon-Quality Steel Pipe From India, Oman, The United Arab Emirates, and Vietnam... determinations by Commerce that imports of circular welded carbon- quality steel pipe from India, Oman,...

  3. 78 FR 72863 - Circular Welded Carbon-Quality Steel Pipe From the People's Republic of China: Continuation of...

    2013-12-04

    ...). \\3\\ See Circular Welded Carbon-Quality Steel Pipe From China, 78 FR 70069 (November 22, 2013). Scope... Carbon Quality Steel Pipe From the People's Republic of China, 73 FR 42547 (July 22, 2008). Continuation... International Trade Administration Circular Welded Carbon-Quality Steel Pipe From the People's Republic of...

  4. 75 FR 29519 - Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China: Rescission of...

    2010-05-26

    ... International Trade Administration Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China... antidumping duty order on certain cut-to-length carbon steel plate (``CTL Plate'') from the People's Republic of China (``PRC''). See Suspension Agreement on Certain Cut- to-Length Carbon Steel Plate From...

  5. 75 FR 67108 - Cut-To-Length Carbon Steel Plate From India, Indonesia, Italy, Japan, and Korea

    2010-11-01

    ... orders on imports of CTL carbon steel plate from India, Indonesia, Italy, and Korea (65 FR 6587) and... COMMISSION Cut-To-Length Carbon Steel Plate From India, Indonesia, Italy, Japan, and Korea AGENCY: United... countervailing duty orders on cut-to-length (``CTL'') carbon steel plate from India, Indonesia, Italy, and...

  6. 75 FR 21241 - Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China: Initiation of...

    2010-04-23

    ... International Trade Administration Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China... determine whether certain imports of certain cut-to-length carbon steel plate (``CTL plate'') are... Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From the People's Republic of...

  7. 78 FR 72863 - Circular Welded Carbon Quality Steel Pipe From the People's Republic of China: Continuation of...

    2013-12-04

    ...'') Review, 78 FR 33063 (June 3, 2013). \\2\\ See Circular Welded Carbon Quality Steel Pipe From the People's... FR 60849 (October 2, 2013). \\3\\ See Circular Welded Carbon-Quality Steel Pipe from China, 78 FR 70069... International Trade Administration Circular Welded Carbon Quality Steel Pipe From the People's Republic of...

  8. 77 FR 64478 - Circular Welded Carbon-Quality Steel Pipe From India: Final Determination of Sales at Less Than...

    2012-10-22

    ... Preliminary Determination, 77 FR at 32562-63. \\3\\ See Circular Welded Carbon-Quality Steel Pipe From India...; Certain Welded Carbon Steel Standard Pipes and Tubes From India, 51 FR 17384 (May 12, 1986). Therefore... International Trade Administration Circular Welded Carbon-Quality Steel Pipe From India: Final Determination...

  9. 78 FR 46570 - Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From Ukraine; Administrative Review

    2013-08-01

    ... International Trade Administration Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From Ukraine... suspending the antidumping investigation of certain cut-to-length carbon steel plate (CTL plate) from Ukraine... Agreement, see Suspension of Antidumping Duty Investigation: Certain Cut-to-Length Carbon Steel Plate...

  10. 77 FR 13093 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Final Results of...

    2012-03-05

    ... International Trade Administration Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea... administrative review of the countervailing duty (``CVD'') order on corrosion-resistant carbon steel flat... Review'' below. \\1\\ See Corrosion-Resistant Carbon Steel Flat Products from the Republic of...

  11. 76 FR 34101 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    2011-06-10

    ... COMMISSION Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia Determinations... determines that revocation of the countervailing duty order on hot-rolled flat-rolled carbon-quality steel...-rolled flat-rolled carbon-quality steel products from Brazil and Japan. Background The...

  12. 76 FR 8772 - Cut-to-Length Carbon Steel Plate From India, Indonesia, Italy, Japan and Korea

    2011-02-15

    ... COMMISSION Cut-to-Length Carbon Steel Plate From India, Indonesia, Italy, Japan and Korea AGENCY: United...-year reviews concerning the countervailing duty orders on cut-to-length carbon steel plate from India, Indonesia, Italy, and Korea and the antidumping duty orders on cut-to-length carbon steel plate from...

  13. 77 FR 72827 - Corrosion-Resistant Carbon Steel Flat Products From Germany and the Republic of Korea: Final...

    2012-12-06

    ... Carbon Steel Flat Products from Germany, 71 FR 66163 (November 13, 2006). Analysis of Comments Received... International Trade Administration Corrosion-Resistant Carbon Steel Flat Products From Germany and the Republic... on certain corrosion- resistant carbon steel flat products (``CORE'') from Germany and the...

  14. 77 FR 31877 - Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea; Scheduling of Full Five...

    2012-05-30

    ... COMMISSION Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea; Scheduling of Full Five... duty order on corrosion-resistant carbon steel flat products from Korea and the antidumping duty orders on corrosion- resistant carbon steel flat products from Germany and Korea would be likely to lead...

  15. 76 FR 80963 - Cut-To-Length Carbon-Quality Steel Plate From India, Indonesia, Italy, Japan, and Korea

    2011-12-27

    ... COMMISSION Cut-To-Length Carbon-Quality Steel Plate From India, Indonesia, Italy, Japan, and Korea... cut-to-length carbon-quality steel plate from India, Indonesia, and Korea would be likely to lead to... antidumping duty order on cut-to-length carbon-quality steel plate from Italy would not be likely to lead...

  16. 78 FR 19210 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Final Results of...

    2013-03-29

    ... International Trade Administration Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea... carbon steel flat products from the Republic of Korea for the period January 1, 2010, through December 31...\\ See Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Preliminary Results...

  17. 78 FR 72114 - Circular Welded Carbon Quality Steel Line Pipe From China; Institution of Five-Year Reviews

    2013-12-02

    ... circular welded carbon quality steel line pipe from China (74 FR 4136). On May 13, 2009, the Department of... COMMISSION Circular Welded Carbon Quality Steel Line Pipe From China; Institution of Five-Year Reviews AGENCY... welded carbon quality steel line pipe from China would be likely to lead to continuation or recurrence...

  18. 77 FR 24221 - Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea; Notice of Commission...

    2012-04-23

    ... COMMISSION Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea; Notice of Commission... countervailing duty order on corrosion-resistant carbon steel flat products from Korea and the antidumping duty orders on corrosion- resistant carbon steel flat products from Germany and Korea would be likely to...

  19. 78 FR 67334 - Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From Ukraine; Final Results of...

    2013-11-12

    ... Carbon Steel Plate From Ukraine; Administrative Review, 78 FR 46570 (August 1, 2013) and accompanying...: Certain Cut-to-Length Carbon Steel Plate from Ukraine, 73 FR 57602 (October 3, 2008) (Agreement). On... International Trade Administration Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From...

  20. 76 FR 66893 - Certain Circular Welded Carbon Steel Pipes and Tubes From India, Thailand, and Turkey; Final...

    2011-10-28

    ..., 75 FR 69626, 69627 (November 15, 2010). Thailand--Welded Carbon Steel Pipe and Tube (A-549-502) The.... See Scope Rulings, 58 FR 27542, (May 10, 1993). Turkey--Welded Carbon Steel Pipe and Tube (A-489-501... Tubes from India, 51 FR 17384 (May 12, 1986); Antidumping Duty Order; Circular Welded Carbon Steel...

  1. 76 FR 64900 - Welded Carbon Steel Pipe and Tube From Turkey: Final Results of Expedited Sunset Review of...

    2011-10-19

    ... International Trade Administration Welded Carbon Steel Pipe and Tube From Turkey: Final Results of Expedited...) initiated a sunset review of the countervailing duty order (CVD) on welded carbon steel pipe and tube from... CVD order on welded carbon steel pipe and tube from Turkey was published in the Federal Register...

  2. 76 FR 33204 - Certain Welded Carbon Steel Pipe and Tube From Turkey; Notice of Preliminary Results of...

    2011-06-08

    ... Order; Welded Carbon Steel Standard Pipe and Tube Products From Turkey, 51 FR 17784 (May 15, 1986... Carbon Steel Pipe and Tube from Turkey, 71 FR 26043 (May 3, 2006), unchanged in Notice of Final Results of Antidumping Duty New Shipper Review: Certain Welded Carbon Steel Pipe and Tube From Turkey, 71...

  3. 76 FR 76939 - Certain Welded Carbon Steel Pipe and Tube From Turkey: Notice of Final Results of Antidumping...

    2011-12-09

    ... International Trade Administration Certain Welded Carbon Steel Pipe and Tube From Turkey: Notice of Final... welded carbon steel pipe and tube from Turkey. The administrative review covers the Borusan Group \\1\\ and... preliminary results of the antidumping duty administrative view of certain welded carbon steel pipe and...

  4. 78 FR 79665 - Welded Carbon Steel Standard Pipe and Tube Products From Turkey: Final Results of Antidumping...

    2013-12-31

    ... Antidumping Duty Order; Welded Carbon Steel Standard Pipe and Tube Products From Turkey, 51 FR 17784, 17784... International Trade Administration Welded Carbon Steel Standard Pipe and Tube Products From Turkey: Final... administrative review of the antidumping duty order on welded carbon steel standard pipe and tube...

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

    Huajie Wu; Yangchun Liu; Jie Fu

    2007-01-01

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

  6. Mechanical Behaviour and Microstructural Characterization of Carbon Steel Samples from Three Selected Steel Rolling Plants

    P. O. Atanda; Abioye, A. A.; A. O. Iyiola

    2015-01-01

    The research investigated the mechanical behavior of samples of steel rods obtained from three selected Steel Rolling Companies in South Western part of Nigeria. This was done by carrying out some mechanical tests such as tensile, impact and hardness as well as microstructural examination.Four sets of 16 mm steel rod samples were collected from Tiger steel industries, Phoenix steel and Oxil steel Industies, all located in South West Nigeria, The chemical composition was carried out using a...

  7. Constitutive model depending upon temperature and strain rate of carbon constructional quality steels

    杨柳; 罗迎社

    2008-01-01

    The basic factors relating to the rheological stress in the constitutive equations were introduced.Carbon constructional quality steels were regarded as a kind of elastic-viscoplastic materials under high temperature and the elastic-viscoplastic constitutive models were summarized.A series of tension experiments under the same temperature and different strain rates,and the same strain rate and different temperatures were done on 20 steel,35 steel and 45 steel.52 groups of rheological stress-strain curves were obtained.The experimental results were analyzed theoretically.The rheological stress constitutive models of carbon steels were built combining the strong points of the Perzyna model and Johnson-Cook model.Comparing the calculation results conducted from the model with the experiment results,the results proves that the model can reflect the temperature effect and strain rate effect of carbon constructional quality steels better.

  8. Solidification of stainless steel slag by accelerated carbonation.

    Johnson, D C; MacLeod, C L; Carey, P J; Hills, C D

    2003-06-01

    On exposure to carbon dioxide (CO2) at a pressure of 3 bars, compacts formed from pressed ground slag, and 12.5 weight percent water, were found to react with approximately 18% of their own weight of CO2. The reaction product formed was calcium carbonate causing the slag to self-cement. Unconfined compressive strengths of 9MPa were recorded in carbonated compacts whereas strengths of < 1 MPa were recorded in non-carbonated slag compacts. As molten stainless steel slag containing dicalcium silicate (C2S) cools it can undergo several phase transitions. The final transformation from the beta-polymorph to gamma-C2S is accompanied by a volume change that causes the slag to self-pulverise or 'dust'. As a consequence of this the fine grained portion of the slag contains more of this phase whilst the coarser particles of the slag contain more of the calcium magnesium silicates that contribute the bulk of the waste. The fine fraction (< 125 microm) of the slag when ground is found to react to the same extent as the ground bulk slag and produces compacts with equivalent strength. A coarser fraction (4-8 mm) when ground to a similar grading does not react as extensively and produces a weaker product. Additions of ordinary Portland cement (OPC) at 5 and 10 percent by weight did not alter the degree of reaction during carbonation of the bulk slag or ground fine fraction, however the strength of the 4-8 mm fraction was increased by this change. PMID:12868521

  9. The possibility of tribopair lifetime extending by welding of quenched and tempered stainless steel with quenched and tempered carbon steel

    V. Marušić; I. Samardžić; Budić, I.; Marušić, L.

    2015-01-01

    In the conditions of tribocorrosion wear, extending of parts lifetime could be achieved by using stainless steel,which is hardened to sufficiently high hardness. In the tribosystem bolt/ bushing shell/link plate of the bucket elevator transporter conveyor machine, the previously quenched and tempered martensitic stainless steel for bolts is hardened at ≈47 HRC and welded with the quenched and tempered high yield carbon steel for bolts. Additional material, based on Cr-Ni-Mo (18/8/6) is used. ...

  10. The kinetics of pitting corrosion of carbon steel

    The development of an improved statistical method for analysing pit growth data to take account of the difference in area of laboratory specimens and full sized high level nuclear waste containers is described. Statistical analysis of data from pit growth experiments with large area (460 cm2) plates of BS 4360 steel have indicated that the depth distributions correlate most closely with a limited distribution function. This correlation implies that previous statistical analyses to estimate the maximum pit depths in full size containers, which were made using unlimited distribution functions, will be pessimistic. An evaluation of the maximum feasible pitting period based on estimating the period during which the oxygen diffusion flux is sufficient to stabilise a passive film on carbon steel containers has indicated that this is of the order of 125 years rather than the full 1000 year container life. The estimate is sensitive to the value of the leakage current assumed to flow through the passive film, and therefore work is planned to measure this accurately in relevant granitic environments. (author)

  11. Simple Predicting Method for Fatigue Crack Growth Rate Based on Tensile Strength of Carbon Steel

    2003-01-01

    Three types of fatigue tests for an annealed carbon steel containing carbon of 0.42 % were carried out on smooth specimens and specimens with a small blind hole in order to investigate the fatigue crack growth law. A simple predicting method for crack growth rates has been proposed involving strength σb and the relation between cyclic stress and strain. The validity of proposed method has been confirmed by experiments on several carbon steels with different loadings.

  12. Effect of Carbon Properties on Melting Behavior of Mold Fluxes for Continuous Casting of Steels

    2006-01-01

    During continuous casting of steel, the properties of mold fluxes strongly affect the casting performance,steel quality and environment of casting operation. The high temperature microscopy technique was used to investigate the melting behaviour of mold fluxes, and drip test method was used to determine their melting rate. The results showed that free carbon is a dominant factor in governing the melting behaviour of fluxes, and the melting rate is increased with increasing carbon reactivity and decreasing carbon content.

  13. Stress corrosion cracking of A515 grade 60 carbon steel

    An investigation was conducted to evaluate the effect of welding method plate thickness, and subsequent stress relief treatment on the stress corrosion cracking propensity of ASTM A515 Grade 60 carbon steel plate exposed to a 5 M NaNO3 solution at 1900F for eight weeks. It was found that all weld coupons receiving no thermal stress relief treatment cracked within eight weeks; all weld coupons given a vibratory stress relief cracked within eight weeks; two of the eight weld coupons stress relieved at 6000F for one hour cracked within eight weeks; none of the weld coupons stress relieved at 11000F for one hour cracked within eight weeks; and that cracking was generally more severe in coupons fabricated from 7/8 inch plate by shielded metal arc welding than it was in coupons fabricated by other welding methods. (U.S.)

  14. Corrosion inhibition of carbon steel by sodium metavanadate

    VIJAYA GOPAL SRIBHARATHY

    2012-08-01

    Full Text Available The inhibition efficiency of sodium metavanadate (SMV-adipic acid (AA system in controlling corrosion of carbon steel in an aqueous solution containing 60 ppm of Cl- has been evaluated by weight-loss method; 250 ppm of SMV exhibits inhibition efficiency of 56 %. Addition of adipic acid to SMV improves the inhibition efficiency of the system. The formulation consisting of 250 ppm of SMV and 250 ppm of adipic acid has inhibition efficiency of 98 %. A synergistic effect exists between SMV and adipic acid with the synergism parameters greater than 1. Mecha¬nistic aspects of corrosion inhibition have been studied by electrochemical methods like potentiodynamic polarization and electrochemical impedance spectroscopy. FTIR spectra reveal that the protective film consists of Fe2+-SMV complex and Fe2+-adipic acid complex. The protective film has been analyzed by fluorescence spectra, SEM and EDAX.

  15. Nondestructive inspection technologies for low-carbon stainless steel

    This report summarized modification and additional items of 'ultrasonic testing guide for in-service inspection of light-water type nuclear power plant components' (JEAG4207-2004) for ultrasonic testing method for Primary Loop of Recirculation system (PLR) piping and core shrouds on the base of four year project on nondestructive inspection technologies for low-carbon stainless steel, which investigated defect detection capability and sizing accuracy for PLR piping and core shrouds, and their explanatory notes on ultrasonic testing method, indication length measurement, phased-array method and defect depth measurement for PLR piping, and indication length measurement and defect depth measurement for core shrouds. 'Eddy current testing guide using upper coil (draft)' for core shrouds was proposed with detailed explanatory notes. (T. Tanaka)

  16. Corrosion fatigue behavior of carbon steel in drilling fluids

    Chaoyang, F.; Jiashen, Z. [Huazhong Univ. of Science and Technology, Wuhan (China)

    1998-08-01

    Corrosion fatigue of carbon steel (CS) in drilling fluids was studied using a self-made rotary bending corrosion fatigue testing apparatus under simulated drilling conditions. Mechanisms of the effects of cyclic stress, chloride (Cl{sup {minus}}), sulfide (S{sup 2{minus}}), and pH of drilling fluids on corrosion fatigue of CS as well as the inhibiting action of the imidazoline inhibitor and oxygen (O{sub 2}) scavenger sodium sulfite (Na{sub 2}SO{sub 3}) on corrosion fatigue were studied. Results showed Cl{sup {minus}} and S{sup 2{minus}} promoted corrosion fatigue crack initiation and growth. Fatigue life was lengthened after reducing subjected stress, increasing the pH of the drilling fluids, or adding the inhibitor and O{sub 2} scavenger.

  17. An evaluation of carbon steel corrosion under stagnant seawater conditions.

    Lee, Jason S; Ray, Richard I; Lemieux, Edward J; Falster, Alexander U; Little, Brenda J

    2004-01-01

    Corrosion of 1020 carbon steel coupons in natural seawater over a 1-year period was more aggressive under strictly anaerobic stagnant conditions than under aerobic stagnant conditions as measured by weight loss and instantaneous corrosion rate (polarization resistance). Under oxygenated conditions, a two-tiered oxide layer of lepidocrocite/goethite formed. The inner layer was extremely tenacious and resistant to acid cleaning. Under anaerobic conditions, the corrosion product was initially a non-tenacious sulphur-rich corrosion product, mackinawite, with enmeshed bacteria. As more sulphide was produced the mackinawite was transformed to pyrrhotite. In both aerobic and anaerobic exposures, corrosion was more aggressive on horizontally oriented coupons compared to vertically oriented samples. PMID:15621645

  18. Investigation of the benzotriazole as addictive for carbon steel phosphating

    This work studied the viability of substitution of sodium nitrite (NaNO2) for benzotriazole (BTAH) in the zinc phosphate bath (PZn+NaNO2) for phosphating of carbon steel (SAE 1010). The characterization of the samples was carried out by Scanning Electron Microscopy, Optical Microscopy and X-ray diffraction. The chemical composition was evaluated by Energy Dispersive Spectroscopy. The corrosion behavior of the samples was investigated by Open Circuit Potential, Electrochemical Impedance Spectroscopy and Anodic Potentiodynamic Polarization Curves in a 0.5 mol L-1 NaCl electrolyte. The experimental results showed that the phosphate layer obtained in the solution with benzotriazole (PZn+BTAH) presented better corrosion resistance properties than that obtained in sodium nitrite. The results demonstrated that the sodium nitrite NaNO2 can be replaced by benzotriazole (BTAH) in zinc phosphate baths. (author)

  19. Environmental review of options for managing radioactively contaminated carbon steel

    The U.S. Department of Energy (DOE) is proposing to develop a strategy for the management of radioactively contaminated carbon steel (RCCS). Currently, most of this material either is placed in special containers and disposed of by shallow land burial in facilities designed for low-level radioactive waste (LLW) or is stored indefinitely pending sufficient funding to support alternative disposition. The growing amount of RCCS with which DOE will have to deal in the foreseeable future, coupled with the continued need to protect the human and natural environment, has led the Department to evaluate other approaches for managing this material. This environmental review (ER) describes the options that could be used for RCCS management and examines the potential environmental consequences of implementing each. Because much of the analysis underlying this document is available from previous studies, wherever possible the ER relies on incorporating the conclusions of those studies as summaries or by reference

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

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

    2011-01-01

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

  1. Influence of Heat Treatments on the Corrosion Resistance of Medium -Carbon Steel using Sulfuric Spring Water

    Ikhlas Basheer

    2013-04-01

    Full Text Available The corrosion is one of the important problems that may be occur to the parts of machinery and equipment after manufactured and when used as a result of exposure to corrosive media. Plain-carbon steel is considered as one of the most common minerals used in industrial applications. Some of heat treatments can have direct effect on the corrosion rate of steel by building up galvanic corrosion cells between its microscopic phases. Therefore, to adopt one of kinds of the plain-carbon steel and the most commonly used in industry to be study subject, that is medium carbon steel and took samples of this steel has been treated thermally in three methods which the normalising, annealing, and hardening .The corrosive media used in the research is Sulfuric Spring, it contains many chemical compounds to show its influence on the corrosion of steel. The weight loss method is used to determine corrosion rate and to compare between the results obtained, show that the greatest corrosion resistance of the annealed steel and the corrosion resistance of the hardened steel is the lowest while the corrosion  resistance of the normalised steel is in-between them.         Calcium carbonate was formed on the metal surface which acts as an isolating layer which decrease corrosion rate with time

  2. Energy use and carbon dioxide emissions in the steel sector in key developing countries

    Price, L.K.; Phylipsen, G.J.M.; Worrell, E.

    2001-04-01

    Iron and steel production consumes enormous quantities of energy, especially in developing countries where outdated, inefficient technologies are still used to produce iron and steel. Carbon dioxide emissions from steel production, which range between 5 and 15% of total country emissions in key developing countries (Brazil, China, India, Mexico, and South Africa), will continue to grow as these countries develop and as demand for steel products such as materials, automobiles, and appliances increases. In this report, we describe the key steel processes, discuss typical energy-intensity values for these processes, review historical trends in iron and steel production by process in five key developing countries, describe the steel industry in each of the five key developing countries, present international comparisons of energy use and carbon dioxide emissions among these countries, and provide our assessment of the technical potential to reduce these emissions based on best-practice benchmarking. Using a best practice benchmark, we find that significant savings, in the range of 33% to 49% of total primary energy used to produce steel, are technically possible in these countries. Similarly, we find that the technical potential for reducing intensities of carbon dioxide emissions ranges between 26% and 49% of total carbon dioxide emissions from steel production in these countries.

  3. Steel slag carbonation in a flow-through reactor system: the role of fluid-flux.

    Berryman, Eleanor J; Williams-Jones, Anthony E; Migdisov, Artashes A

    2015-01-01

    Steel production is currently the largest industrial source of atmospheric CO2. As annual steel production continues to grow, the need for effective methods of reducing its carbon footprint increases correspondingly. The carbonation of the calcium-bearing phases in steel slag generated during basic oxygen furnace (BOF) steel production, in particular its major constituent, larnite {Ca2SiO4}, which is a structural analogue of olivine {(MgFe)2SiO4}, the main mineral subjected to natural carbonation in peridotites, offers the potential to offset some of these emissions. However, the controls on the nature and efficiency of steel slag carbonation are yet to be completely understood. Experiments were conducted exposing steel slag grains to a CO2-H2O mixture in both batch and flow-through reactors to investigate the impact of temperature, fluid flux, and reaction gradient on the dissolution and carbonation of steel slag. The results of these experiments show that dissolution and carbonation of BOF steel slag are more efficient in a flow-through reactor than in the batch reactors used in most previous studies. Moreover, they show that fluid flux needs to be optimized in addition to grain size, pressure, and temperature, in order to maximize the efficiency of carbonation. Based on these results, a two-stage reactor consisting of a high and a low fluid-flux chamber is proposed for CO2 sequestration by steel slag carbonation, allowing dissolution of the slag and precipitation of calcium carbonate to occur within a single flow-through system. PMID:25597686

  4. Development of Low and Middle Carbon Martensite Spring Steel with High Strength and Toughness for Automobile

    Li Ye-sheng; Wu Zi-ping; Zhu Yin-lu; Chen Hui-huang

    2004-01-01

    The conventional middle and high carbon spring steels have some drawbacks in properties, production and application. In order to meet the demands of rapid development of automobile, a new low and middle carbon spring steel35Si2CrMnVB, C0.34, Sil.66, Mn0.80, Cr0.67, V0.13, B0.001, P0.011, S0.014 wt.%, has been developed. Comparison between the new spring steel 35Si2CrMnVB and the conventional spring steel 60Si2MnA, C0.61, Sil.75, Mn0.76, P0.021,S0.018 wt.%, shows that the new spring steel has not only high strength, good ductility, good comprehensive mechanical properties, but also low decarbonization tendency, sufficient hardenability and high elastic sag resistance, etc.. The microstructure change in quenched steel caused by the decreasing of carbon contents is detected through metallographic observation, the new low and middle carbon spring steel 35Si2CrMnVB after quenching is composed of almost lath martensite with high dislocation density and only a little martensite with twin structure. It is testified that to develop low carbon spring steel with more excellent properties for automobile is feasible.

  5. Recent Progress in High Strength Low Carbon Steels

    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.

  6. Coordinated control of carbon and oxygen for ultra-low-carbon interstitial-free steel in a smelting process

    Min Wang; Yan-ping Bao; Quan Yang; Li-hua Zhao; Lu Lin

    2015-01-01

    Low residual-free-oxygen before final de-oxidation was beneficial to improving the cleanness of ultra-low-carbon steel. For ul-tra-low-carbon steel production, the coordinated control of carbon and oxygen is a precondition for achieving low residual oxygen during the Ruhrstahl Heraeus (RH) decarburization process. In this work, we studied the coordinated control of carbon and oxygen for ultra-low-carbon steel during the basic oxygen furnace (BOF) endpoint and RH process using data statistics, multiple linear regressions, and thermodynamics computations. The results showed that the aluminum yield decreased linearly with increasing residual oxygen in liquid steel. When the mass ratio of free oxygen and carbon ([O]/[C]) in liquid steel before RH decarburization was maintained between 1.5 and 2.0 and the carbon range was from 0.030wt%to 0.040wt%, the residual oxygen after RH natural decarburization was low and easily controlled. To satisfy the re-quirement for RH decarburization, the carbon and free oxygen at the BOF endpoint should be controlled to be between 297 × 10−6 and 400 × 10−6 and between 574 × 10−6 and 775 × 10−6, respectively, with a temperature of 1695 to 1715°C and a furnace campaign of 1000 to 5000 heats.

  7. Coordinated control of carbon and oxygen for ultra-low-carbon interstitial-free steel in a smelting process

    Wang, Min; Bao, Yan-ping; Yang, Quan; Zhao, Li-hua; Lin, Lu

    2015-12-01

    Low residual-free-oxygen before final de-oxidation was beneficial to improving the cleanness of ultra-low-carbon steel. For ultra-low-carbon steel production, the coordinated control of carbon and oxygen is a precondition for achieving low residual oxygen during the Ruhrstahl Heraeus (RH) decarburization process. In this work, we studied the coordinated control of carbon and oxygen for ultra-low-carbon steel during the basic oxygen furnace (BOF) endpoint and RH process using data statistics, multiple linear regressions, and thermodynamics computations. The results showed that the aluminum yield decreased linearly with increasing residual oxygen in liquid steel. When the mass ratio of free oxygen and carbon ([O]/[C]) in liquid steel before RH decarburization was maintained between 1.5 and 2.0 and the carbon range was from 0.030wt% to 0.040wt%, the residual oxygen after RH natural decarburization was low and easily controlled. To satisfy the requirement for RH decarburization, the carbon and free oxygen at the BOF endpoint should be controlled to be between 297 × 10-6 and 400 × 10-6 and between 574 × 10-6 and 775 × 10-6, respectively, with a temperature of 1695 to 1715°C and a furnace campaign of 1000 to 5000 heats.

  8. Creep testing and viscous behavior research on carbon constructional quality steel under high temperature

    余敏; 罗迎社; 彭相华

    2008-01-01

    Creep tests under at a certain temperature and different stress levels were performed on two carbon constructional quality steels at a certain stress level and different temperatures,and their creep curves at high temperature were obtained based on analyzing the testing data.Taking 45 steel at a certain temperature and stress as the example,the integral creep constitutive equation and the differential stress-strain constitutive relationship were established based on the relevant rheological model,and the integral core function was also obtained.Simultaneously,the viscous coefficients denoting the viscous behavior in visco-plastic constitutive equation were determined by taking use of the creep testing data.Then the viscous coefficients of three carbon steels(20 steel,35 steel and 45 steel) were compared and analyzed.The results show that the viscosity is different due to different materials at the same temperature and stress.

  9. Galvanic Interaction between Chalcopyrite and Pyrite with Low Alloy and High Carbon Chromium Steel Ball

    Asghar Azizi

    2013-01-01

    Full Text Available This study was aimed to investigate the galvanic interaction between pyrite and chalcopyrite with two types of grinding media (low alloy and high carbon chromium steel ball in grinding of a porphyry copper sulphide ore. Results indicated that injection of different gases into mill altered the oxidation-reduction environment during grinding. High carbon chromium steel ball under nitrogen gas has the lowest galvanic current, and low alloy steel ball under oxygen gas had the highest galvanic current. Also, results showed that the media is anodic relative to pyrite and chalcopyrite, and therefore pyrite or chalcopyrite with a higher rest potential acted as the cathode, whilst the grinding media with a lower rest potential acted as the anode, when they are electrochemically contacted. It was also found that low alloy steel under oxygen produced the highest amount of EDTA extractable iron in the slurry, whilst high carbon chromium steel under nitrogen atmosphere led to the lowest amount.

  10. MORPHOLOGY MODIFICATION OF CARBON CHROME MOLYBDENUM STEEL STRUCTURE INFLUENCED BY HEAT TREATMENT

    V. A. Lutsenko

    2011-01-01

    Full Text Available The influence of temperature and time parameters of thermal treatment on structural change and properties of carbon chromium molybdenum steel has been studied. It has been shown that there are considerable areas with grainy morphology of cementite after high temperature tempering in the structure of steel. It assures reduction of steel microhardness by 25%, and there are no substantial structural changes after medium temperature tempering.

  11. MORPHOLOGY MODIFICATION OF CARBON CHROME MOLYBDENUM STEEL STRUCTURE INFLUENCEDBY HEAT TREATMENT

    Lutsenko, V.; Anelkin, N.; Golubenko, T.; Scherbakov, V.; Lutsenko, O.

    2011-01-01

    The influence of temperature and time parameters of thermal treatment on structural change and properties of carbon chromium molybdenum steel has been studied. It has been shown that there are considerable areas with grainy morphology of cementite after high temperature tempering in the structure of steel. It assures reduction of steel microhardness by 25%, and there are no substantial structural changes after medium temperature tempering.

  12. Morphology modification of carbon chrome molybdenum steel structure influenced by heat treatment

    V. A. Lutsenko; N. L. Anelkin; T. N. Golubenko; Scherbakov, V. I.; O. V. Lutsenko

    2011-01-01

    The influence of temperature and time parameters of thermal treatment on structural change and properties of carbon chromium molybdenum steel has been studied. It has been shown that there are considerable areas with grainy morphology of cementite after high temperature tempering in the structure of steel. It assures reduction of steel microhardness by 25%, and there are no substantial structural changes after medium temperature tempering.

  13. Stress state evaluation in low carbon and TRIP steels by magnetic permeability

    Kouli, M.-E.; Giannakis, M.

    2016-03-01

    Magnetic permeability is an indicative factor for the steel health monitoring. The measurements of magnetic permeability lead to the evaluation of the stress state of any ferromagnetic steel. The magnetic permeability measurements were conducted on low carbon and TRIP steel samples, which were subjected to both tensile and compressive stresses. The results indicated a direct correlation of the magnetic permeability with the mechanical properties, the stress state and the microstructural features of the examined samples.

  14. Reinforcement steel corrosion in passive state and by carbonation: Consideration of galvanic currents and interface steel - concrete defaults

    This thesis aims to study the durability of nuclear waste deep storage structures. The work carried out is essentially an experimental study, and focuses on the corrosion of steel in the passive state with aerated or non-aerated conditions on the one hand, and the corrosion of steel in carbonated concrete during the propagation phase on the other hand. Indeed, the pore solution of concrete in contact with the metal is alkaline (pH between 12 and 13). Under these conditions, steel reinforced concrete remains passive by forming a stable and protective oxide layer (corrosion of steel in the passive state). This passive layer limits the steel corrosion rate at very low values (negligible on a short life time) but not null. For the nuclear waste storage structures due to a very long life time (up to several hundred years), this low corrosion rate can become a risk. Therefore, it is necessary to study the evolution of the oxide layer growth over time. The objectives of the thesis are to study the influence of the steel-concrete interface quality on reinforcement corrosion in passive and active state, and the possible occurrence of galvanic corrosion currents between different reinforcement steel areas. (author)

  15. 76 FR 67407 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Preliminary Results of Antidumping...

    2011-11-01

    ... Alloy Steel Wire Rod from Mexico, (76 FR 45509 (July 29, 2011)). We preliminarily determine that, during... and Certain Alloy Steel Wire Rod from Mexico, 71 FR 27989 (May 15, 2006). Therefore, pursuant to... merchandise subject to this order is certain hot-rolled products of carbon steel and alloy steel, in coils,...

  16. 76 FR 62039 - Certain Hot-Rolled Carbon Steel Flat Products From India: Final Results of 2009-2010 Antidumping...

    2011-10-06

    ... referred to as interstitial-free (``IF'')) steels, high-strength low-alloy (``HSLA'') steels, and the... to stabilize carbon and nitrogen elements. HSLA steels are recognized as steels with micro-alloying...: Notice of Preliminary Results of 2009-2010 Antidumping Duty Administrative Review, 76 FR 31938 (June...

  17. 76 FR 42679 - Certain Hot-Rolled Carbon Steel Flat Products From India: Final Results of Antidumping Duty...

    2011-07-19

    ...-alloy (``HSLA'') steels, and the substrate for motor lamination steels. IF steels are recognized as low... to as columbium), or both, added to stabilize carbon and nitrogen elements. HSLA steels are... Preliminary Results of Antidumping Duty Administrative Review, 76 FR 2344 (January 13, 2011)...

  18. 75 FR 27297 - Certain Hot-Rolled Carbon Steel Flat Products from India: Notice of Final Results of Antidumping...

    2010-05-14

    ...-alloy (``HSLA'') steels, and the substrate for motor lamination steels. IF steels are recognized as low... to as columbium), or both, added to stabilize carbon and nitrogen elements. HSLA steels are... Results of Antidumping duty Administrative Review, and Intent to Rescind in Part, 75 FR 1031 (January...

  19. 76 FR 31938 - Certain Hot-Rolled Carbon Steel Flat Products From India: Notice of Preliminary Results of 2009...

    2011-06-02

    ..., high-strength low-alloy (``HSLA'') steels, and the substrate for motor lamination steels. IF steels are... commonly referred to as columbium), or both, added to stabilize carbon and nitrogen elements. HSLA steels... India, 66 FR 60194 (December 3, 2001) (``Amended Final Determination''). On December 1, 2010,...

  20. Mechanical Behaviour and Microstructural Characterization of Carbon Steel Samples from Three Selected Steel Rolling Plants

    P. O. Atanda

    2015-11-01

    Full Text Available The research investigated the mechanical behavior of samples of steel rods obtained from three selected Steel Rolling Companies in South Western part of Nigeria. This was done by carrying out some mechanical tests such as tensile, impact and hardness as well as microstructural examination.Four sets of 16 mm steel rod samples were collected from Tiger steel industries, Phoenix steel and Oxil steel Industies, all located in South West Nigeria, The chemical composition was carried out using a Spectrometer (EDX3600B. Afterwards, different samples were prepared, cut and machined according to ASTM standards dimensions of tensile and impact tests as well as hardness test from which their Ultimate tensile Strength, Yield strength, Percentage elongation, Impact strength and Brinell hardness number were obtained and compared to three standards (ASTM A706, BS 4449 and Nst 65- Mn. Their microstructures were also examined and analyzed.The results showed that the Ultimate tensile strength for the samples from Oxil steel, Phoenix Steel and Tiger steel were 661 N/(mm2 , 653 N/(mm2 and 631 N/(mm2 respectively while their hardness values were 150 BHN, 178 BHN, 214 BHN respectively. The sample from Tiger steel and Oxil Steel had the finest and most coarse microstructure respectively. In conclusion, it was observed that the results of the sample analysis from the three selected Steel Rolling Companies conformed to most of the standards except the sample from Tiger steel which had a high hardness value compared to the standard.

  1. Fatigue of carbon and low-alloy steels in LWR environments

    Fatigue tests have been conducted on A106-Gr B carbon steel and A533-Gr B low-alloy steel to evaluate the effects of an oxygenated-water environment on the fatigue life of these steels. For both steels, environmental effects are modest in PWR water at all strain rates. Fatigue data in oxygenated water confirm the strong dependence of fatigue life on dissolved oxygen (DO) and strain rate. The effect of strain rate on fatigue life saturates at some low value, e.g., between 0.0004 and 0.001%/s in oxygenated water with ∼0.8 ppm DO. The data suggest that the saturation value of strain rate may vary with DO and sulfur content of the steel. Although the cyclic stress-strain and cyclic-hardening behavior of carbon and low-alloy steels is distinctly different, the degradation of fatigue life of these two steels with comparable sulfur levels is similar. The carbon steel exhibits pronounced dynamic strain aging, whereas strain-aging effects are modest in the low-alloy steel. Environmental effects on nucleation of fatigue crack have also been investigated. The results suggest that the high-temperature oxygenated water has little or no effect on crack nucleation

  2. Microbial Methane Production Associated with Carbon Steel Corrosion in a Nigerian Oil Field.

    Mand, Jaspreet; Park, Hyung S; Okoro, Chuma; Lomans, Bart P; Smith, Seun; Chiejina, Leo; Voordouw, Gerrit

    2015-01-01

    Microbially influenced corrosion (MIC) in oil field pipeline systems can be attributed to many different types of hydrogenotrophic microorganisms including sulfate reducers, methanogens and acetogens. Samples from a low temperature oil reservoir in Nigeria were analyzed using DNA pyrotag sequencing. The microbial community compositions of these samples revealed an abundance of anaerobic methanogenic archaea. Activity of methanogens was demonstrated by incubating samples anaerobically in a basal salts medium, in the presence of carbon steel and carbon dioxide. Methane formation was measured in all enrichments and correlated with metal weight loss. Methanogens were prominently represented in pipeline solids samples, scraped from the inside of a pipeline, comprising over 85% of all pyrosequencing reads. Methane production was only witnessed when carbon steel beads were added to these pipeline solids samples, indicating that no methane was formed as a result of degradation of the oil organics present in these samples. These results were compared to those obtained for samples taken from a low temperature oil field in Canada, which had been incubated with oil, either in the presence or in the absence of carbon steel. Again, methanogens present in these samples catalyzed methane production only when carbon steel was present. Moreover, acetate production was also found in these enrichments only in the presence of carbon steel. From these studies it appears that carbon steel, not oil organics, was the predominant electron donor for acetate production and methane formation in these low temperature oil fields, indicating that the methanogens and acetogens found may contribute significantly to MIC. PMID:26793176

  3. Microbial methane production associated with carbon steel corrosion in a Nigerian oil field

    Jaspreet eMand

    2016-01-01

    Full Text Available Microbially influenced corrosion (MIC in oil field pipeline systems can be attributed to many different types of hydrogenotrophic microorganisms including sulfate reducers, methanogens and acetogens. Samples from a low temperature oil reservoir in Nigeria were analyzed using DNA pyrotag sequencing. The microbial community compositions of these samples revealed an abundance of anaerobic methanogenic archaea. Activity of methanogens was demonstrated by incubating samples anaerobically in a basal salts medium, in the presence of carbon steel and carbon dioxide. Methane formation was measured in all enrichments and correlated with metal weight loss. Methanogens were prominently represented in pipeline solids samples, scraped from the inside of a pipeline, comprising over 85% of all pyrosequencing reads. Methane production was only witnessed when carbon steel beads were added to these pipeline solids samples, indicating that no methane was formed as a result of degradation of the oil organics present in these samples. These results were compared to those obtained for samples taken from a low temperature oil field in Canada, which had been incubated with oil, either in the presence or in the absence of carbon steel. Again, methanogens present in these samples catalyzed methane production only when carbon steel was present. Moreover, acetate production was also found in these enrichments only in the presence of carbon steel. From these studies it appears that carbon steel, not oil organics, was the predominant electron donor for acetate production and methane formation in these low temperature oil fields, indicating that the methanogens and acetogens found may contribute significantly to MIC.

  4. 75 FR 69125 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From China

    2010-11-10

    ..., and by publishing the notice in the Federal Register on May 11, 2010 (75 FR 26273). The hearing was... COMMISSION Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From China Determination... alloy steel standard, line, and pressure pipe (``seamless SLP pipe''), provided for in subheadings...

  5. Enhancing tensile properties of ultrafine-grained medium-carbon steel utilizing fine carbides

    Highlights: → Tensile properties of UFG carbon steels were enhanced by imbedding fine carbides. → Thinner pearltic lamellae induced finer carbides after caliber-rolling process. → Superior tensile properties were attributed to the enhanced strain hardening rate. → Yield-point phenomenon in UFG steels resulted from stronger effect of particle growth. - Abstract: The aim of the present study is to evaluate the influence of nano-sized carbides upon tensile behavior in UFG medium-carbon steels and to develop a material with improved tensile properties. UFG medium-carbon steels with fine carbides were successfully fabricated by multi-pass caliber rolling at 773 K. Alloying chromium and molybdenum resulted in thinner pearlitic lamellae, which were transformed into finer particles after severe plastic deformation. The UFG steel containing the alloying elements exhibited superior tensile properties, which was attributed to the enhanced strain hardening rate by the imbedded finer particles. Subsequent annealing induced growth of grains and particles, which also recovered elongation at the expense of strength. All UFG steels investigated here showed a yield-point phenomenon due to the decreased hardening rate and lack of mobile dislocations and their sources. The deteriorating effect of particle growth overwhelmed the improving effect of grain growth after annealing of the UFG medium-carbon steel, leading to a reduced strain hardening rate. This resulted in a positive correlation between a grain size and Lueders elongation in the investigated UFG steels.

  6. 77 FR 54926 - Certain Seamless Carbon and Alloy Steel; Standard, Line, and Pressure Pipe From Germany

    2012-09-06

    ... FR 19711) and determined on July 6, 2012, that it would conduct an expedited review (77 FR 42763... COMMISSION Certain Seamless Carbon and Alloy Steel; Standard, Line, and Pressure Pipe From Germany... steel standard, line, and pressure pipe from Germany would be likely to lead to continuation...

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

    A. M. Nesterenko

    2009-01-01

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

  8. 78 FR 34335 - Certain Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Preliminary Results of...

    2013-06-07

    ... of Antidumping Duties, 68 FR 23954 (May 6, 2003). Cash Deposit Requirements The following cash... Steel Pipes and Tubes From Taiwan: Antidumping Duty Order, 49 FR 19369 (May 7, 1984). These cash deposit... International Trade Administration Certain Circular Welded Carbon Steel Pipes and Tubes From Taiwan:...

  9. 75 FR 36635 - Circular Welded Carbon Steel Pipes and Tubes From Thailand: Rescission of Antidumping Duty...

    2010-06-28

    ... FR 9162 (March 1, 2010). On March 31, 2010, we received a timely request from Saha Thai Steel Pipe... Revocation in Part, 75 FR 22107 (April 27, 2010). Rescission of Antidumping Duty Administrative Review The... International Trade Administration Circular Welded Carbon Steel Pipes and Tubes From Thailand: Rescission...

  10. 77 FR 44213 - Corrosion-Resistant Carbon Steel Flat Products From Germany and the Republic of Korea...

    2012-07-27

    ... Corrosion-Resistant Carbon Steel Flat Products from Germany, 71 FR 66163 (November 13, 2006). Analysis of... Steel Flat Products From Canada and Germany, 71 FR 14498 (March 22, 2006). \\7\\ See Notice of Final... International Trade Administration Corrosion-Resistant Carbon Steel Flat Products From Germany and the...

  11. 75 FR 62566 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    2010-10-12

    ... COMMISSION Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia AGENCY: United... countervailing duty order on hot-rolled flat-rolled carbon-quality steel products (``hot-rolled steel'') from... that full reviews pursuant to section 751(c)(5) of the Act should proceed (75 FR 42782, July 22,...

  12. 78 FR 40429 - Certain Hot-Rolled Carbon Steel Flat Products From India: Rescission of Countervailing Duty...

    2013-07-05

    ... Reviews and Request for Revocation in Part, 78 FR 25418, 25422 (May 1, 2013). U.S. Steel and Nucor... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From India: Rescission of... administrative review of the ] countervailing duty order on certain hot-rolled carbon steel flat products...

  13. 76 FR 26694 - Certain Hot-Rolled Carbon Steel Flat Products From India: Final Rescission of Countervailing Duty...

    2011-05-09

    ... FR 74682 (December 1, 2010). On January 3, 2011, we received from United States Steel Corporation, a... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From India: Final Rescission of... countervailing duty (CVD) order on certain hot-rolled carbon steel flat products from India. See Antidumping...

  14. 78 FR 40428 - Certain Hot-Rolled Carbon Steel Flat Products from India: Rescission of Antidumping Duty...

    2013-07-05

    ..., 78 FR 6291 (January 30, 2013) (Initiation Notice). \\2\\ See id., 78 FR 6292. Nucor and U.S. Steel... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products from India: Rescission of... administrative review of the antidumping duty order on certain hot- rolled carbon steel flat products (hot...

  15. 78 FR 55241 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Preliminary Results of...

    2013-09-10

    ...: Certain Steel Products From Korea, 58 FR 43752 (August 17, 1993) (Order). \\3\\ See the ``Decision... International Trade Administration Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea... carbon steel flat products (CORE) from the Republic of Korea (Korea) for the period of review...

  16. 78 FR 16832 - Corrosion-Resistant Carbon Steel Flat Products From Germany and the Republic of Korea: Revocation...

    2013-03-19

    ...-Year (``Sunset'') Review, 77 FR 85 (January 3, 2012). \\2\\ See Corrosion-Resistant Carbon Steel Flat... Corrosion- Resistant Carbon Steel Flat Products From Germany and Korea, 77 FR 301 (January 4, 2012). As a... Steel Flat Products From Germany and Korea, 78 FR 15376 (March 11, 2013) and Corrosion-Resistant...

  17. 77 FR 47593 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Preliminary Results...

    2012-08-09

    ... Fair Value: Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China, 62 FR 61964.... Included in this description is hot-rolled iron and non-alloy steel universal mill plates (i.e., flat... International Trade Administration Certain Cut-to-Length Carbon Steel Plate From the People's Republic of...

  18. 78 FR 76279 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Final Results and...

    2013-12-17

    ... hot-rolled iron and non-alloy steel universal mill plates (i.e., flat-rolled products rolled on four... International Trade Administration Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China... certain cut-to- length carbon steel plate (``CTL plate'') from the People's Republic of China...

  19. 75 FR 8301 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Final Results of...

    2010-02-24

    ... 31, 2008. Scope of the Order The products covered by the order are hot-rolled carbon steel universal... steel flat-rolled products in straight lengths, of rectangular shape, hot- rolled, neither clad, plated... International Trade Administration A-570-849 Certain Cut-to-Length Carbon Steel Plate From the People's...

  20. 75 FR 2487 - Circular Welded Carbon Steel Pipes and Tubes from Thailand: Court Decision Not in Harmony with...

    2010-01-15

    ... Steel Pipes and Tubes from Thailand: Final Results of Antidumping Duty Administrative Review, 73 FR... International Trade Administration Circular Welded Carbon Steel Pipes and Tubes from Thailand: Court Decision... results of the administrative review of the antidumping order on circular welded carbon steel pipes...

  1. Molybdenum-containing ultra low-carbon bainitic steels for heavy plate applications

    A new family of molybdenum-containing ultra low-carbon bainitic (ULCB) structural steels has been investigated. These new steels were developed to replace conventional quenched plus tempered (Q+T) high yield strength steels. The results to date have indicated that a proper choice of alloy design and thermomechanical processing can lead to a very attractive family of steels with good mechanical properties in the as-hot rolled condition in sections up to 25.4 mm (1 in.) thick. Studies in progress have indicated that these steels can be used in heavy plate sections up to 100 mm (4 in.) with different molybdenum and nickel combinations than those reported in this paper. Another major advantage of the ULCB steels is that the weldability of these steels and their resistance to underbead cracking should both be considerably improved because of the very low carbon content in these molybdenum-containing ULCB steels. Preliminary weldability studies currently in progress indicate that these new steels have good weldability without the need for pre- and post-heating as that required for Q+T steels

  2. THE INFLUENCE OF CARBON STEEL STRUCTURAL COMPONENTS DISPERSION ON FRACTURE RESISTANCE

    I. O. Vakulenko; M. A. Hryshchenko; O. M. Perkov

    2007-01-01

    The observed questions of estimate stress intensity coefficient, strength of fatique and toughness behavior is considered to be result of a directional variation in the grain size of austenite and size of ferrite pearlite in carbon steel.

  3. Measurement of hydrogen content in carbon steel exposed to hydrogen gas environment

    Carbon steel overpacks for high level radioactive waste disposal would be attacked corrosion due to water reduction under reducing condition and the hydrogen would be generated by the corrosion reaction. When the hydrogen is absorbed into metal in the solution or in the hydrogen gas environment, the metal is sometimes damaged by the hydrogen embrittlement. In this study, hydrogen content in carbon steel specimens were measured after the exposure to hydrogen gas environment of 10 MPa, 100degC which is regarded as the most severe case under repository condition. As the results of measurement, the absorbed hydrogen concentration in carbon steel was 0.02∼0.03 ppm and it was concluded that the hydrogen embrittlement due to the contact with hydrogen gas would not be likely to occur on carbon steel overpack under the repository condition. (author)

  4. Modeling of chemical transition of nitrate accompanied with corrosion of carbon steel under alkaline conditions

    Interaction between carbon steel and nitrate was modeled using the mixed potential concept. Carbon steel was selected as an example of metal components in the repository of radioactive wastes. The nitrate reduction accompanied with the corrosion of carbon steel was modeled as a reaction series of NO3- → NO2- → NH3. The sum of the current of the reaction series of NO3- → NO2- → NH3 and that of water reduction was assumed to be balanced with the oxidation current of carbon steel. The input parameters for this kinetic model were determined by electrochemical measurements and immersion tests. The results of the immersion tests can be interpreted by the analyses of the model. (author)

  5. APPLICATION OF BARIUMSTRONTIUM CARBONATES FOR PROCESSING OF CREEP-RESISTING STEELS

    A. P. Bezhok

    2015-11-01

    Full Text Available The results of researches on influence of bariumstrontium carbonates on structure, mechanical and foundry properties of heat resisting chrome-nickel steels of austenitic type are given.

  6. Trial manufacturing of titanium carbon-steel composite overpack for high-level radioactive waste disposal

    The overpack, a barrier enclosing the high-level radioactive waste (HLW), is designed to maintain complete containment for at least 1000 years. The titanium carbon-steel composite overpack adopts an outside titanium layer as a corrosion resistance to protect the inside carbon-steel body. The corrosion-proof overpack design could decrease the thickness of the shell, which complies with efficient space utilization in the disposal vault. Trial fabrication of actual size titanium carbon-steel composite overpack has been carried out to demonstrate the engineering feasibility and to extract the subjects for future improvement. The major dimensions of the cylindrical shape overpack are 1777 mm long, 914 mm outer diameter and 440 mm diameter hole to contain the HLW. Although manufacturing processes had not been optimized yet, the engineering feasibility of the titanium carbon-steel composite overpack was demonstrated successfully. (author)

  7. Hybrid use of steel and carbon-fiber reinforced concrete for monitoring of crack behavior

    Ding, Yining; Han, Z; Zhang, Y.; Azevedo, Cecília Maria

    2012-01-01

    In order to study the damage after concrete cracking, the influence of the combined use of steel fiber and carbon fiber on the conductivity and crack resistance of concrete beam under flexural loading were investigated. Carbon fiber and steel fiber were added as diphasic conductive materials to produce the electric conductive and ductile concrete. This paper reports the experimental and analytical work associated with establishing the crack width in relation to the fractional c...

  8. Zn-10.2% Fe coating over carbon steel atmospheric corrosion resistance. Comparison with zinc coating

    Zn-10.2% Fe galvanized coating versus hot galvanized coating over carbon steel corrosion performance has been studied. Different periods of atmospheric exposures in various Valencia Community sites, and salt spray accelerated test have been done. Carbon steel test samples have been used simultaneously in order to classify exposure atmosphere corrosivity, and environmental exposure atmosphere characteristics have been analyzed. Corrosion Velocity versus environmental parameters has been obtained. (Author) 17 refs

  9. Investigation of the Potential of Jatropha Seed Oil as Austempering Quenchant for Medium Carbon Steel

    Akor, T; Ashwe, A., Ikpambese, K.K., and Yaji, P.M.

    2014-01-01

    This study investigates the suitability of jatropha seed oil as quenching medium for austempering medium carbon steel. Test samples were austenitized at 9500C; socked for 1hr; austempered for varying periods of 1, 2, 3, 4 and 5hrs. The result showed significant increase in tensile strength and impact energy apart from achieving an appreciable increase in hardness. It also tally with recommended values of medium carbon steel austempered in salt bath, implying that jatropha oil can be used as h...

  10. ACCELERATED CARBONATION OF STEEL SLAG COMPACTS: DEVELOPMENT OF HIGH STRENGTH CONSTRUCTION MATERIALS

    Mieke eQuaghebeur

    2015-12-01

    Full Text Available Mineral carbonation involves the capture and storage of carbon dioxide in carbonate minerals. Mineral carbonation presents opportunities for the recycling of steel slags and other alkaline residues that are currently landfilled. The Carbstone process was initially developed to transform non-hydraulic steel slags (stainless steel slag and basic oxygen furnace slags in high quality construction materials. The process makes use of accelerated mineral carbonation by treating different types of steel slags with CO2 at elevated pressure (up to 2 MPa and temperatures (20 to 140°C. For stainless steel slags raising the temperature from 20 to 140°C had a positive effect on the CO2 uptake, strength development and the environmental properties (i.e. leaching of Cr and Mo of the carbonated slag compacts. For BOF slags raising the temperature was not beneficial for the carbonation process. Elevated CO2 pressure and CO2 concentration of the feed gas had a positive effect on the CO2 uptake and strength development for both types of steel slags. In addition also the compaction force had a positive effect on the strength development. The carbonates that are produced in-situ during the carbonation reaction act as a binder, cementing the slag particles together. The carbonated compacts (Carbstones have technical properties that are equivalent to conventional concrete products. An additional advantage is that the carbonated materials sequester 100 to 150 g CO2/kg slag. The technology was developed on lab scale by optimisation of process parameters with regard to compressive strength development, CO2 uptake and environmental properties of the carbonated construction materials. The Carbstone technology was validated using (semi-industrial equipment and process conditions.

  11. Influence of the impurities on the depth of penetration with carbon steel weldings

    O. Savytsky

    2014-04-01

    Full Text Available In this paper the results of the research about the influence of the impurities on the depth of penetration with carbon steels weldings of different chemical composition are presented. These data suggest that presence of those impurities, such as sulphure and oxygen, in the steel, increases the depth of penetration to 1,3 - 1,5 times compared to welding refined steels. Applying activating fluxes for welding high tensile steels, provides an increase in the depth of penetration of 2 - 3 times.

  12. Inhibition of carbon steel corrosion by 11-aminoundecanoic acid

    Saad Ghareba

    2015-12-01

    Full Text Available The current study reports results on the investigation of the possibility of using 11-aminoundecanoic acid (AA as an inhibitor of general corrosion of carbon steel (CS in HCl under a range of experimental conditions: inhibitor concentration, exposure time, electrolyte temperature and pH and CS surface roughness. It was found that AA acts as a mixed-type inhibitor, yielding maximum inhibition efficiency of 97 %. The adsorption of AA onto the CS surface was described by the Langmuir adsorption isotherm. The corresponding apparent Gibbs free energy of AA adsorption on CS at 295 K was calculated to be −30.2 kJ mol–1. The adsorption process was found to be driven by a positive change in entropy of the system. PM-IRRAS measurements revealed that the adsorbed AA layer is amorphous, which can be attributed to the repulsion between the neighboring positively charged amine groups and a high heterogeneity of the CS surface. It was also found that the AA provides very good corrosion protection of CS of various surface roughness, and over a prolonged time.

  13. Welding of carbon steel vessels without post weld heat treatment

    The methods available for the repair welding of carbon steel vessels without post weld heat treatment and with particular reference to service in a sour environment have been reviewed. All the available techniques have the common aim of providing adequate properties in the weld metal and heat affected zone without the need for a full post weld stress relief. The heat that is required to provide the necessary metallurgical changes comes, therefore, from an alternate source. The two sources used are heat from suitably placed subsequent weld passes or from localized external heat sources. The technique presently being used by Ontario Hydro to repair vessels subject to sour service utilizes both a high preheat and a welding technique which is designed to temper the heat affected zone formed in the base material by the first weld pass. This technique is an improvement over the 'half bead' techniques given in the ASME X1 code and has been shown to be capable of reducing the hardness of the heat affected zone to an acceptable level. Certain recommendations have been made which could improve control of the technique presently used by Ontario Hydro and provide measurable parameters between procedural tests and the actual weld repairs

  14. Acceptance criteria for corroded carbon steel piping containing weld defects

    Acceptance criteria for corroded low temperature, low pressure carbon steel piping containing weld defects is presented along with a typical application of these criteria. They are intended to preclude gross rupture or rapidly propagating failure due to uniform wall thinning, local wall thinning, pitting corrosion and weld defects. The minimum allowable uniform wail thickness is based on the code-of-record allowable stress and fracture criteria. Weld defects are postulated as potential sites for fracture initiation. CEGB/R6 failure assessment diagram is used as the fracture criteria to determine the minimum allowable wall thickness. Design of a large portion of the low temperature, low pressure piping is dominated by axial stresses. Existing local wall thinning acceptance criteria address high pressure piping where hoop stress dominates the design. The existing criteria is over conservative, in some cases, when used on low pressure piping. Local wall thinning criteria is developed to limit the axial stress on the locally thinned section, based on a reduced average thickness. Limits on pit density are also developed to provide acceptance criteria for pitted piping

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

    Maoyu ZHAO; Qianwang CHEN

    2013-01-01

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

  16. Elucidation of mechanism wear carbon steel with structure of martensite

    I. A. Vakulenko

    2013-04-01

    Full Text Available Purpose. The purpose of the paper is an estimation of degree of metal hardness change for the railway wheel with martensite structure during rolling. Methodology. As strength characteristic the Rockwell hardness is used. Wear tests were conducted in the conditions of normal loading with (10% and without sliding on the test equipment SMTs-2. Parameters of the fine crystalline structure (tetragonality degree of the crystalline grid, dislocation density, scale of coherent scattering regions, and disturbance value of the crystalline grid of second kind are determined by the methods of X-ray structural analysis. Findings. During operation of the railway wheels with different strength level, origin of defects on the wheel thread is caused by simultaneous action of both the friction forces and the cyclically changing loadings. Considering that formation of damage centers is largely determined by the state of metal volumes near the wheel thread, one should expect the differences in friction processes development at high contact stress for the wheels with different strength level and structural state. Originality. During the wear tests softening effect of carbon steel with martensite quenching structure is obtained. Softening effect equaled 3.5–7% from the level of quenched metal hardness. The softening effect is accompanied by the reduction of tetragonality degree of the crystalline structure of martensite, reduction of coherent scattering regions, dislocation density increase and crystalline grid disturbance of the second kind. Practical value. The results point out the necessity for further studies to clarify the resulted softening effect mechanism.

  17. Decrudding and chemical cleaning of carbon steel components - an evaluation

    Corrosion and accumulation of corrosion products on the surfaces of structural components and plant equipments can cause se vereoperational problems during service. An illustration is the heat exchanger systems in nuclear power stations. Development and standardisation of appropriate chemical cleaning and decontamination procedures and their evaluation hence merit serious consideration. A number of chemical cleaning procedures using formulations based on hydrochloric and citric acid solutions have been examined to study their crud dissolving and derusting ability in addition to the attack on base material. The compositions were chosen: (1) along with complexing agents EDTA and ammonium citrate, (2) with pH control, and (3) with the use of inhibitors acridine, rhodine, hexamine and phenyl-thiourea. The evaluations have been made at 28 and 60 deg C. Rusted carbon steel coupons having a rust of 10-12 mg/cm2 on the surface have been used for the purpose of the above evaluations. Data on corrosion rates of monel and cupronickel (70:30) in the descaling solutions have also been presented. Results on the above evaluation studies have been discussed. (author)

  18. Effect of phosphonium-based ionic liquids on the corrosion of carbon steel under gamma radiation

    The interactions of two ionic liquids with carbon steel surfaces were studied in absence and presence of γ-radiation. Both studied ionic liquids were found to corrode the carbon steel. One of the ionic liquids (labelled [P66614]+ [Br]-) was found to produce corrosion products both with and without radiation present. The second ionic liquid (labelled [P66614]+ [NTf2]-) did not corrode the steel in absence of γ-radiation, but did corrode it in the presence of γ-radiation. (author)

  19. Carbide formation on carbon steels in CO2 corrosion by use of applied anodic current

    Laethaisong, Nushjarin

    2011-01-01

    The present study aims to validate the method in enriching of iron carbide surface from carbon steels in CO2 corrosion. Applying an anodic current to carbon steel electrodes by galvanostatic measurement was a selected approach. Influence of magnitude of the applied current and exposure time on the corrosion process was studied. The experiments were conducted with CO2-saturated-0.5M NaCl solution as an electrolyte at room temperature and atmospheric pressure. Three different steels, X-65, St52...

  20. Studies of the properties of heat treated rolled medium carbon steel

    Daramola O. Oluyemi

    2011-01-01

    Full Text Available Investigations were carried out to study critically the effects of heat treatment on the properties of rolled medium carbon steel. Representative samples of as-rolled medium carbon steel were subjected to heat treatment processes which are; Quenching, Lamellae Formation and Tempering in the following order (Q + Q + L + T, (Q + L + T and (L + T. The steel was heated to the austenizing temperature of 830 ºC and water quenched. The quenched steel was subjected to lamellae formation by reheating it to the ferrite-austenite dual-phase region at a temperature of 745 ºC below the effective A C3 point and then rapidly quenched in water. The lamellae formed was tempered at 480 ºC to provide an alloy containing strong, tough and lath martensite in a soft and ductile ferrite matrix. Mechanical tests were carried out on the samples and the results shows that the steel developed has excellent combination of tensile strength, hardness and impact strength which is very good for structural applications. The corrosion behaviour of the samples; heat treated rolled medium carbon steel and as-rolled medium carbon steel in sodium chloride medium were also investigated from where it was also confirmed that improved corrosion resistance is achievable by the treatment.

  1. Risk management for low carbon steels in the reactor coolant loop

    The codes and regulations give engineers some flexibility in the materials to be used in nuclear power for the power train. As long as multiple levels of containment are in place, it is low carbon steels for such items as pumps, pipes, valves and other fittings. This paper proposes the use of low carbon steels in many places where stainless steels have been used traditionally. The risk of materials failure is shown to be equal, or less than, with stainless steels. This is evidenced with a discussion of the mechanisms by which failure occurs. The benefits of using low carbon steels are multiple: cost, ease of maintenance, less down time and availability of replacement parts. It is also proposed that use of low carbon steels will make the individual components more safe, because mass produced, commercially-tested products are used instead of special-order, single-source items. The authors presume that additional safety measures will be needed to compensate for the higher perceived safety offered by stainless steel materials. These are suggested to be additional controls, in the form of sensors, monitoring points and other electronic devices linked to a central computer monitor

  2. The CCT diagrams of ultra low carbon bainitic steels and their impact toughness properties

    The CCT diagrams of ULCBNi steels, HN3MV, HN3MVCu having 5.1% Ni and 3.5% Ni and Cu bearing steels; HN3M1.5Cu, HSLA 100 have been determined. The reduced carbon concentration in steel, in order to prevent the formation of cementite, allowed for using nickel, manganese, chromium and molybdenum to enhance hardenability and refinement of the bainitic microstructures by lowering BS temperature. Copper and microadditions of vanadium and niobium are successfully used for precipitation strengthening of steel both in thermomechanically or heat treated conditions. Very good fracture toughness at low temperatures and high yield strength properties of HN3MVCu and HN3MV steels allowed for fulfillment of the requirements for steel plates for pressure vessels and cryogenic applications. (author)

  3. Effect of Cr content, hardness and micro structure on flow-accelerated corrosion in carbon steel pipes. Examination of replaced carbon steel pipes

    68 replaced carbon steel piping in secondary system of pressurized water reactor (PWR) has been investigated by visual examination for checking thinning conditions. It is well known that the flow-accelerated corrosion (FAC) was inhibited by traces of Cr in steel. Therefore, the chemical compositions of those steels have been measured. In addition, the micro structure and hardness of those steels have been investigated. And the relationship between those material variables and FAC rate was considered. As the results, (1) The Cr contents in those steels were below 0.1 wt% except one sample. Minute quantities of chromium increase the resistance against FAC. But the water velocity was thought to be the dominant factor rather than chemical composition in steel, at least such as below 0.1%Cr. (2) Hardness of all piping has been satisfied the specifications of each materials. The hardness of steels was not correlated with wall thinning rate. (3) The micro structure was also not correlated with FAC rate. (author)

  4. N-heterocyclic Amine Derivatives as Efficient Corrosion Inhibitors for Carbon Steel in Acidic Medium

    A novel heterocyclic amine derivatives, namely N, N'-substituted pyridinyl ethylene diamine tetra acetic acid sodium salt (A) and ethylene diamine N, N'-diacetic acid di (2-methylene tetra hydro furfuryl) acetate (B) were synthesized and their structure confirmations were performed by FTIR, HNMR and CNMR spectra. The inhibition effectiveness was evaluated against the corrosion of carbon steel in 1 M HCl by weight loss and polarization techniques. The results showed that the synthesized derivatives are good corrosion inhibitors for carbon steel in 1 M HCl medium, their inhibition efficiency, increased with inhibitor concentration, and (A) is slightly more effective than (B). The potentiostatic polarization study showed that (A) and (B) are mixed-type inhibitors in 1 M HCl. These compounds prevent carbon steel from corrosion by adsorption to the steel surface and forming insoluble complexes with ferrous species. The weight loss results and potentiostatic polarization studies were in reasonable agreement. (author)

  5. Corrosion of Carbon Steel and Corrosion-Resistant Rebars in Concrete Structures Under Chloride Ion Attack

    Mohamed, Nedal; Boulfiza, Mohamed; Evitts, Richard

    2013-03-01

    Corrosion of reinforced concrete is the most challenging durability problem that threatens reinforced concrete structures, especially structures that are subject to severe environmental conditions (i.e., highway bridges, marine structures, etc.). Corrosion of reinforcing steel leads to cracking and spalling of the concrete cover and billions of dollars are spent every year on repairing such damaged structures. New types of reinforcements have been developed to avoid these high-cost repairs. Thus, it is important to study the corrosion behavior of these new types of reinforcements and compare them to the traditional carbon steel reinforcements. This study aimed at characterizing the corrosion behavior of three competing reinforcing steels; conventional carbon steel, micro-composite steel (MMFX-2) and 316LN stainless steel, through experiments in carbonated and non-carbonated concrete exposed to chloride-laden environments. Synthetic pore water solutions have been used to simulate both cases of sound and carbonated concrete under chloride ions attack. A three-electrode corrosion cell is used for determining the corrosion characteristics and rates. Multiple electrochemical techniques were applied using a Gamry PC4™ potentiostat manufactured by Gamry Instruments (Warminster, PA). DC corrosion measurements were applied on samples subjected to fixed chloride concentration in the solution.

  6. 76 FR 7546 - Certain Hot-Rolled Carbon Steel Flat Products From Brazil: Rescission of Countervailing Duty...

    2011-02-10

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From Brazil: Rescission of... review of the countervailing duty order on certain hot- rolled carbon steel flat products (hot-rolled... Agreement Suspending the Countervailing Duty Investigation on Hot- Rolled Flat-Rolled Carbon-Quality...

  7. The possibility of tribopair lifetime extending by welding of quenched and tempered stainless steel with quenched and tempered carbon steel

    V. Marušić

    2015-04-01

    Full Text Available In the conditions of tribocorrosion wear, extending of parts lifetime could be achieved by using stainless steel,which is hardened to sufficiently high hardness. In the tribosystem bolt/ bushing shell/link plate of the bucket elevator transporter conveyor machine, the previously quenched and tempered martensitic stainless steel for bolts is hardened at ≈47 HRC and welded with the quenched and tempered high yield carbon steel for bolts. Additional material, based on Cr-Ni-Mo (18/8/6 is used. The microstructure and hardness of welded samples are tested. On the tensile tester, resistance of the welded joint is tested with a simulated experiment. Dimensional control of worn tribosystem elements was performed after six months of service.

  8. 75 FR 18788 - Circular Welded Carbon Steel Pipes and Tubes from Thailand: Preliminary Results and Rescission...

    2010-04-13

    ...: Circular Welded Carbon Steel Pipes and Tubes from Thailand, 51 FR 8341 (March 11, 1986). On March 2, 2009... Shipper Review Final Results, 75 FR at 4529-4530 (January 28, 2010). Allied Tube responded to Pacific Pipe... Review, 73 FR 61019 (October 15, 2008) (2006-2007 AR Final Results); see Circular Welded Carbon...

  9. EFFECTS OF CARBON CONTENT AND ROLLING PROCESSING ON RETAINED AUSTENITE FOR HOT-ROLLED TRIP STEELS

    Y. Chen; X. Chen; Z.X. Yuan; B.F. Xu; A.M. Guo; P.H. Li; S.K. Pu

    2002-01-01

    The effects of finishing rolling temperature and coiling temperature on retained austen-ire were studied for hot-rolled transformation induced plasticity (TRIP) steels withdifferent carbon content. The experimental results showed that an appropriate volumefraction of retained austenite from 6% to 11% could be obtained according to the dif-ferent carbon content less than 0.20% by controlled finishing rolling and coiling forthe hot-rolled TRIP steels. It can be concluded that carbon content has a significanteffect on the fraction of retained austenite and coiling processing plays stronger roleon retaining austenite than fishing rolling processing.

  10. A computational model for the carbon transfer in stainless steel sodium systems

    A method is proposed of computing the carbon transfer in the type 316, 304 and 321 stainless steels in sodium environment as a function of temperature, exposure time and carbon concentration in the sodium. The method is based on the criteria developed at ANL by introducing some simplifications and takes also into account the correlations obtained at WARD. Calculated carbon profiles are compared both with experimental data and with the results available by the other computer methods. The limits for quantitative predictions of the stainless steel carburization or decarburization exposed in a specific environment are discussed. (author)

  11. Microstructure, mechanical properties and corrosion behavior of laser welded dissimilar joints between ferritic stainless steel and carbon steel

    Highlights: • Laser welding of ferritic stainless steel to carbon steel joints was made. • The microstructure of this dissimilar joint is lath martensite and ferrite. • Decarburized layer and type II grain boundary was observed in joints. • The hardness distribution of two heat input joints across interface were analyzed. • Ecorr of dissimilar joint is between two base metals and joint has greatest icorr. - Abstract: The joint of dissimilar metals between ferritic stainless steel (FSS) and low carbon steel (CS) are welded by laser beam with two different welding speeds: 12 mm/s and 24 mm/s. Microstructure of dissimilar joint were investigated using optical microscope, X-ray diffraction and scanning electron microscope. The results show that the microstructure of this dissimilar joint is lath martensite and few ferrite, upper bainite and widmanstatten ferrite formed in heat-affected zone (HAZ) of CS. An increase of welding speed leads to narrower HAZ of CS and higher hardness of weld bead close to FSS side. The joints with different welding speed have similar ultimate tensile strength but superior elongation is obtained of high welding speed joint. Electrochemical corrosion test indicates the corrosion potential of dissimilar joint falls in between FSS and CS. And dissimilar joint has greatest corrosion current density which is attributed to the effect of galvanic corrosion

  12. Microstructure and crack resistance of low carbon Cr-Ni and Cr-Ni-W steel after austempering

    Avdjieva, Tatyana; Tsutsumanova, Gichka; Russev, Stoyan; Staevski, Konstantin

    2013-09-01

    The microstructure of the low carbon Cr-Ni steel after slow cooling from austenization temperature represents a mix of granulated bainite with islands from carbon-rich martensite and carbon-poor austenite. After quick cooling throwing in salt bath from austenization temperature the microstructure is lath bainite. However, in the same treatment conditions, the microstructure of the low carbon Cr-Ni-W steel is different — clusters consist from lath ferrite and retained austenite, disposed in the frame of parent's austenite grains. The cooling velocity has no effect upon the structure making. The impact toughness of the steel with tungsten content is bigger than the steel without tungsten.

  13. Nano-scaled iron-carbon precipitates in HSLC and HSLA steels

    2007-01-01

    This paper studies the composition, quantity and particle size distribution of nano-scaled precipitates with size less than 20 nm in high strength low carbon (HSLC) steel and their effects on mechanical properties of HSLC steel by means of mass balance calculation of nano-scaled precipitates measured by chemical phase analysis plus SAXS method, high-resolution TEM analysis and thermodynamics calculation, as well as temper rapid cooling treatment of ZJ330. It is found that there existed a large quantity of nano-scaled iron-carbon precipitates with size less than 18 nm in low carbon steel produced by CSP and they are mainly Fe-O-C and Fe-Ti-O-C precipitates formed below temperature A1. These precipitates have ob- vious precipitation strengthening effect on HSLC steel and this may be regarded as one of the main reasons why HSLC steel has higher strength. There also existed a lot of iron-carbon precipitates with size less than 36 nm in HSLA steels.

  14. Nano-scaled iron-carbon precipitates in HSLC and HSLA steels

    FU Jie; WU HuaJie; LIU YangChun; KANG YongLin

    2007-01-01

    This paper studies the composition, quantity and particle size distribution of nano-scaled precipitates with size less than 20 nm in high strength Iow carbon (HSLC) steel and their effects on mechanical properties of HSLC steel by means of mass balance calculation of nano-scaled precipitates measured by chemical phase analysis plus SAXS method, high-resolution TEM analysis and thermodynamics calculation, as well as temper rapid cooling treatment of ZJ330. It is found that there existed a large quantity of nano-scaled iron-carbon precipitates with size less than 18 nm in Iow carbon steel produced by CSP and they are mainly Fe-O-C and Fe-Ti-O-C precipitates formed below temperature A1. These precipitates have obvious precipitation strengthening effect on HSLC steel and this may be regarded as one of the main reasons why HSLC steel has higher strength. There also existed a lot of iron-carbon precipitates with size less than 36 nm in HSLA steels.

  15. Ferrite morphology and residual phases in continuously cooled low carbon steels

    Although much research has been conducted on the isothermal transformation products of medium to high carbon hardenable steels, relatively little has been reported for transformation of low carbon structural steels under continuous cooling conditions. The trend towards reduced carbon levels (less than about 0.1 wt% C) has been driven by demands for formability and weldability, challenging steel designers to maintain strength by microalloying and/or thermomechanical controlled processing. Although control of the ferritic products formed in low carbon steels after hot rolling, normalising and welding is essential in order to ensure adequate strength and toughness, understanding of the microstructures formed on continuous cooling is still limited. In addition, transformation mechanisms remain controversial because of polarisation of researchers into groups championing diffusional and displacive theories for the transformation of austenite over a wide range of cooling rates. The present review compares and draws together the main ferrite classification schemes, and discusses some critical issues on kinetics and mechanisms, in an attempt to rationalise the effects of cooling rate, prior austenite structure and composition on the resulting ferrite structure and its mechanical properties. It is concluded that with increasing cooling rate the ferritic product becomes finer, more plate-like, more dislocated, more carbon supersaturated, more likely to be formed by a displacive mechanism, harder and stronger. Other conclusions are that: (i) 'bainitic ferrite', which is a pervasive form of ferrite in continuously cooled low carbon steels, is different from the conventional upper and lower bainites observed in higher carbon steels, insofar as the co-product 'phase' is typically martensite-austenite islands rather than cementite; and (ii) low carbon bainite rather than martensite is the dominant product at typical fast cooling rates (<500K/s) associated with commercial

  16. Corrosion behaviour of carbon steel in contact with bentonite under anaerobic condition

    Full text of publication follows: The geological disposal system of high-level radioactive waste (HLW) consists of vitrified waste, overpack, buffer material and surrounding rock. In this system, overpack is required to prevent the contact of groundwater from vitrified waste for 1000 years. The main factor limiting this function is corrosion due to the contact with groundwater infiltrated to buffer material which is the mixture of bentonite and sand. Carbon steel is selected as one of the candidate materials for overpacks in Japan as a corrosion allowance metal. The deep underground environment for geological disposal of HLW is expected to be relatively oxidizing condition at the initial stage of repository, but it will be returned to reducing as the consumption of oxygen by the corrosion of overpack and the redox reactions with the minerals in buffer material. It is necessary to understand the corrosion behaviour of carbon steel under such anaerobic condition for the lifetime prediction of carbon steel overpack. In this study, immersion tests of carbon steel in buffer material were performed in nitrogen atmosphere in which oxygen gas concentration was controlled less than 1 ppm. The corrosion rates of carbon steel were measured by weight loss of the specimens and the corrosion products were analysed by SEM, XRD and EPMA. For investigating the influence of welding of overpack, welded samples by electron-beam welding (EBW) were used in some of the tests. Synthetic sea water (SSW) and aqueous solutions containing bicarbonate ion and chloride ion were chosen as simulated groundwater. The results indicated that the corrosion form of carbon steel under anaerobic condition was uniform corrosion and no localised corrosion such as pitting, crevice corrosion was found within our experimental conditions. Ferrous carbonate such as FeCO3 or Fe2(OH)2CO3 was identified as crystalline corrosion products by XRD. Although the corrosion rate was affected by test solution and buffer

  17. Corrosion behaviour of carbon steel in contact with bentonite under anaerobic condition

    Naoki, Taniguchi; Susumu, Kawakami [Japan Nuclear Cycle Development Institute, Tokai-mura, Ibaraki (Japan); Manabu, Kawasaki; Mitsuru, Kubota [Inspection Development Corporation, Tokai-mura, Ibaraki (Japan)

    2004-07-01

    Full text of publication follows: The geological disposal system of high-level radioactive waste (HLW) consists of vitrified waste, overpack, buffer material and surrounding rock. In this system, overpack is required to prevent the contact of groundwater from vitrified waste for 1000 years. The main factor limiting this function is corrosion due to the contact with groundwater infiltrated to buffer material which is the mixture of bentonite and sand. Carbon steel is selected as one of the candidate materials for overpacks in Japan as a corrosion allowance metal. The deep underground environment for geological disposal of HLW is expected to be relatively oxidizing condition at the initial stage of repository, but it will be returned to reducing as the consumption of oxygen by the corrosion of overpack and the redox reactions with the minerals in buffer material. It is necessary to understand the corrosion behaviour of carbon steel under such anaerobic condition for the lifetime prediction of carbon steel overpack. In this study, immersion tests of carbon steel in buffer material were performed in nitrogen atmosphere in which oxygen gas concentration was controlled less than 1 ppm. The corrosion rates of carbon steel were measured by weight loss of the specimens and the corrosion products were analysed by SEM, XRD and EPMA. For investigating the influence of welding of overpack, welded samples by electron-beam welding (EBW) were used in some of the tests. Synthetic sea water (SSW) and aqueous solutions containing bicarbonate ion and chloride ion were chosen as simulated groundwater. The results indicated that the corrosion form of carbon steel under anaerobic condition was uniform corrosion and no localised corrosion such as pitting, crevice corrosion was found within our experimental conditions. Ferrous carbonate such as FeCO{sub 3} or Fe{sub 2}(OH){sub 2}CO{sub 3} was identified as crystalline corrosion products by XRD. Although the corrosion rate was affected by

  18. A review of degradation modes of low carbon steel in brine environments

    A literature search was conducted to review information on degradation modes of low carbon steel in brine solutions. A computer search was used to obtain articles from 1970 to present while a manual search was conducted for articles published prior to 1970. The published articles and reports indicated that uniform corrosion occurred in sea water, geothermal brines and simulated repository brines. The uniform corrosion rate increased with decreasing pH, increasing oxygen contest of brine and increasing temperature. Pitting of low carbon steel in brine solutions was related to scale formation due to presences of sulfur and heavy metal ions or mill scale present prior to exposure. Low carbon steel did not appear to be susceptible to stress corrosion cracking, but data was limited. The presence of anaerobic bacteria greatly increased the rate of corrosion of low carbon steel as compared to sterile conditions. If sufficient hydrogen is present, low carbon steel could fail due to hydrogen embrittlement in brine solutions. However, this is an area where experimental work needs to be done under more specific conditions related to salt repositories. Corrosion fatigue and stray current corrosion require specific conditions to occur which can be avoided during waste storage and were there fore not addressed. Also, galvanic effects were not addressed as it will be possible to minimize galvanic effects by design. 226 refs., 4 tabs

  19. Development of Evaluation Technology for Prevention of Two-Phase FAC on Carbon Steel

    Kim, Kyung Mo; Shim, Heesang; Lee, Eun Hee; Hur, Do Haeng [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    There are many pipelines to be managed from wall thinning by flow accelerated corrosion (FAC) in the secondary system of a nuclear power. FAC is a process in which a normally protective oxide layer on the internal carbon or low-alloy steel piping surface dissolves into a stream of flowing water or a wet steam mixture. In this process, the oxide layer becomes thinner and the corrosion rate increases until the corrosion rate and dissolution rates are equal. Recent researches and reports indicate that the FAC problem is prevalent in spite of the development of an inspection method and management skills applying computer programs. Therefore, it is important to mitigate or prevent FAC on the carbon steel, and surface coating technology has been investigated for pipeline systems in a steam flow. Since the occurrence of a Surry-2 pipe rupture accident, a lot of effort has been made to manage the FAC of carbon steel piping. Some of the chemicals were known as a corrosion inhibitor. Bateman et al. reported that the addition of Ti may decrease the FAC rate of carbon steel by ∼ 65 %, TiO{sub 2} was also effective in mitigating the stress corrosion cracking of steam generator tubes under concentrated crevice conditions. A platinum doping method was applied as another mitigation strategy of carbon steel wall thinning. Noble metal, including Pt, had produced the layers of a very high catalyst concentration and this catalytic effect induced a lower corrosion potential for nickel alloys.

  20. Corrosion of carbon steel, zinc and copper by air pollution in Chongqing

    YE Di; ZHAO Da-wei; CHEN Gang-cai; ZHANG Dong-bao

    2007-01-01

    This paper presents the research on the atmospheric corrosion rates of carbon steel, zinc and copper in Chongqing, which was a corrosion subprogram of an international project, Regional Air Pollution in Developing Countries. We performed field exposure tests of carbon steel, zinc and copper at an urban site Guanyinqiao and a rural site Tieshanping inChongqing, then used grey relational analysis, based on the database of the whole corrosion project, to determine the order of the effect of environmental factors on corrosion rates of tested metals, and established dose-response functions for these three metals. The results showed that the two crucial agents of acidic environment, SO2 and H+, were common factors that contributed most to the corrosion of the tested metals. The established dose-response functions for outdoor carbon steel and zinc are proved applicable to use in Chongqing, but the function for copper needs further modifying. We employed these dose-response functions and general environmental data to elaborate the maps of corrosion rate respectively of carbon steel and zinc by geological information system (GIS) technique which help to identify areas of high corrosion damage risk. An acceptable annual average SO2 level of 21 μg/m3 for carbon steel and that of 61 μg/m3 for zinc are also put forward to control the air pollution impact on atmospheric corrosion in Chongqing urban areas.

  1. Development of Evaluation Technology for Prevention of Two-Phase FAC on Carbon Steel

    There are many pipelines to be managed from wall thinning by flow accelerated corrosion (FAC) in the secondary system of a nuclear power. FAC is a process in which a normally protective oxide layer on the internal carbon or low-alloy steel piping surface dissolves into a stream of flowing water or a wet steam mixture. In this process, the oxide layer becomes thinner and the corrosion rate increases until the corrosion rate and dissolution rates are equal. Recent researches and reports indicate that the FAC problem is prevalent in spite of the development of an inspection method and management skills applying computer programs. Therefore, it is important to mitigate or prevent FAC on the carbon steel, and surface coating technology has been investigated for pipeline systems in a steam flow. Since the occurrence of a Surry-2 pipe rupture accident, a lot of effort has been made to manage the FAC of carbon steel piping. Some of the chemicals were known as a corrosion inhibitor. Bateman et al. reported that the addition of Ti may decrease the FAC rate of carbon steel by ∼ 65 %, TiO2 was also effective in mitigating the stress corrosion cracking of steam generator tubes under concentrated crevice conditions. A platinum doping method was applied as another mitigation strategy of carbon steel wall thinning. Noble metal, including Pt, had produced the layers of a very high catalyst concentration and this catalytic effect induced a lower corrosion potential for nickel alloys

  2. The effects of bacteria on the corrosion behavior of carbon steel in compacted bentonite

    As a part of evaluation of corrosion life of carbon steel overpack, the experimental studies have been performed on the effects of bacteria on the corrosion behavior of carbon steel in compacted bentonite using iron bacteria (IB) as a representative oxidizing bacteria and sulphur reducing bacteria (SRB) as a representative reducing bacteria. The results of the experimental studies showed that; The activity of SRB was low in compacted bentonite in spite of applying suitable condition for the action of bacteria such as temperature and nutritious solution. Although the corrosion behavior of carbon steel was affected by the existence of bacteria in simple solution, the corrosion rates of carbon steel in compacted bentonite were several μ m/year -10 μ m/year irrespective of coexistence of bacteria and that the corrosion behavior was not affected by the existence of bacteria. According to these results, it was concluded that the bacteria would not affect the corrosion behavior of carbon steel overpack under repository condition. (author)

  3. Study of FAC rate of carbon steels based on characterization of oxide film

    Effects of Cr content and environmental factors, pH and dissolved oxygen concentration, on removal rate of carbon steels due to flow accelerated corrosion have been examined by experiments. Cr content holds a strong impact on the FAC rate regardless of pH values from 6.84 to 10.4. Addition of 1% Cr to carbon steel reduces the FAC rate by one order of magnitude under the environmental conditions, where magnetite forms. Detailed characterizations of oxide film formed on the specimen have been carried out by using SEM and TEM. Preferential corrosion of pearlite phase has been observed at specimen surface of low Cr content steel in early stage of FAC. It has been suggested that oxide structure and porosity were obviously different between low and high Cr content steels. (author)

  4. Evaluation of carbon diffusion in heat treatment of H13 tool steel under different atmospheric conditions

    Maziar Ramezani

    2015-04-01

    Full Text Available Although the cost of the heat treatment process is only a minor portion of the total production cost, it is arguably the most important and crucial stage on the determination of material quality. In the study of the carbon diffusion in H13 steel during austenitization, a series of heat treatment experiments had been conducted under different atmospheric conditions and length of treatment. Four austenitization atmospheric conditions were studied, i.e., heat treatment without atmospheric control, heat treatment with stainless steel foil wrapping, pack carburization heat treatment and vacuum heat treatment. The results showed that stainless steel foil wrapping could restrict decarburization process, resulting in a constant hardness profile as vacuum heat treatment does. However, the tempering characteristic between these two heat treatment methods is different. Results from the gas nitrided samples showed that the thickness and the hardness of the nitrided layer is independent of the carbon content in H13 steel.

  5. Corrosion of stainless and carbon steels in molten mixtures of industrial nitrates

    Goods, S.H.; Bradshaw, R.W. [Sandia National Labs., Livermore, CA (United States); Prairie, M.R.; Chavez, J.M. [Sandia National Labs., Albuquerque, NM (United States)

    1994-03-01

    Corrosion behavior of two stainless steels and carbon steel in mixtures of NaNO{sub 3} and KNO{sub 3} was evaluated to determine if impurities found in commodity grades of alkali nitrates aggravate corrosivity as applicable to an advanced solar thermal energy system. Corrosion tests were conducted for 7000 hours with Types 304 and 316 stainless steels at 570C and A36 carbon steel at 316C in seven mixtures of NaNO{sub 3} and KNO{sub 3} containing variations in impurity concentrations. Corrosion tests were also conducted in a ternary mixture of NaNO{sub 3}, KNO{sub 3}, and Ca(NO{sub 3}){sub 2}. Corrosion rates were determined by descaled weight losses while oxidation products were examined by scanning electron microscopy, electron microprobe analysis, and X-ray diffraction. The nitrate mixtures were periodically analyzed for changes in impurity concentrations and for soluble corrosion products.

  6. EFFECT OF CARBON CONTENT ON MICROSTRUCTURE AND PROPERTIES OF HIGH STRENGTH AND HIGH ELONGATION STEELS

    Y.Chen; X.Chen; 等

    2003-01-01

    The microstructure and mechanical properties of new kind of hot-rolled high strength and high elongation steels with retained austenite were studied by discussing the in-fluence of different carbon content.The research results indicate that carbon content has a significant effect on retaining austenite and consequently resulting in high elon-gation.Besides,new findings about relationship between carbon content and retained austenite as well as properties were discussed in the paper.

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

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

    2003-10-01

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

  8. Corrosion behaviour of carbon steel in buffer material under anaerobic condition

    The deep underground environment for geological disposal of HLW will be relatively oxidizing condition at the initial stage of repository, but it will be returned to reducing as the consumption of oxygen by the corrosion of overpack and the reactions with the minerals in buffer material. It is necessary to understand the corrosion behaviour of carbon steel under such reducing condition for the lifetime prediction of carbon steel overpack. In this study, immersion tests of carbon steel in buffer material were performed in nitrogen atmosphere in which oxygen gas concentration was controlled less than 1 ppm. The corrosion rates of carbon steel were measured by weight loss of the specimens and the corrosion products were analysed by SEM, XRD and EPMA. For investigating the influence of welding of overpack, welded samples by electron-beam welding (EBW) were used for some of the tests. Synthetic sea water (SSW) and aqueous solutions containing bicarbonate ion and chloride ion were chosen as simulated groundwater. According to the experimental results, corrosion products layer contained ferrous carbonate such as FeCO3 and Fe2(OH)2CO3. The average corrosion rates within 1 year were relatively high (4-18 μm/y), but the growths of corrosion after 1 year were decreased rapidly. The increase in average corrosion depths from 1 to 3 (or 4) years was only less than several micro-meters, and the realistic corrosion rates after 1 year were estimated to be less than 1 μm/y in many cases. There was no influence of welding on the corrosion rate of carbon steel up to 3 years of immersion period. The effects of the density of buffer material and the mixing ratio of sand in buffer material on the corrosion rate of carbon steel were also investigated in this study. (author)

  9. 78 FR 33809 - Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's Republic of...

    2013-06-05

    ...In response to a request from an interested party, United States Steel Corporation (``U.S. Steel''), the Department of Commerce (``the Department'') initiated an administrative review of the antidumping duty order on seamless carbon and alloy steel standard, line, and pressure pipe from the People's Republic of China. The period of review is November 1, 2011, through October 31, 2012. Based on......

  10. Evolution of Microstructure and Precipitation State during Thermomechanical Processing of a Low Carbon Microalloyed Steel

    Valles, P.; Gómez, Manuel; Medina, Sebastián F.; Pastor, A.; Vilanova, O.

    2012-01-01

    The increasing demand of sources of energy such as oil and natural gas induces at the steel industry a development on low carbon microalloyed steels for pipeline applications in order to achieve excellent mechanical properties of strength and toughness at a reduced cost. To obtain an adequate fine-grained final structure, the strict control of thermomechanical processing and accelerated cooling is crucial. Depending on the thermomechanical processing conditions and chemical composition, pipel...

  11. THE RELATIONSHIP BETWEEN PITTING SUSCEPTIBILITY AND INCLUSIONS IN CARBON STEELS IN ARTIFICIAL SEAWATER

    X.D. Kong; X.Q. Chen; W.S. Chang; D.B. Chen; J.X. Zheng

    2001-01-01

    The pittings of five carbon steels have been studied by using anodic polarization test and microscope observation. The results show that pitting susceptibilities are related to the types and shapes of inclusions which are the sites of pitting initiation. The pitting initiating at inclusion needs a potential which is defined as pitting potential and the pitting potential is determined by the type and shape of inclusion. The influence of oxygen content in steel on pitting potential is also discussed.

  12. Microstructural characterization of carbon steels using ultrasonic velocity measurements

    Vera Lúcia de Araújo Freitas; Antonio Almeida Silva; Edgard de Macedo Silva; de Albuquerque, Victor Hugo C.; João Manuel Ribeiro da Silva Tavares

    2009-01-01

    Non-destructive techniques are suitable alternatives for analysis and microstructural characterization of steels#8217; phases. Based on this, this work aims to analyze the behavior of longitudinal and transverse ultrasonic velocities in three different types of AISI steels: 1006, 1080 and quenched 1045. These materials were selected due to their distinct microstructures: ferrite, pearlite and martensite, respectively. By measuring sound velocities for both longitudinal and transversal waves, ...

  13. Corrosion Behavior of Carbon Steels in CCTS Environment

    Cabrini, M; S. Lorenzi; T. Pastore

    2016-01-01

    The paper reports the results of an experimental work on the effect of steel microstructures on morphology and protectiveness of the corrosion scale formed in water saturated by supercritical CO2. Two HSLA steels were tested. The microstructures were modified by means of different heat treatments. Weight loss was measured after exposure at CO2 partial pressure of 80 bar and 60°C temperature. The morphology of the scale was analyzed by means of scanning electron microscope (SEM) energy-dispers...

  14. Evolution of carbides and carbon content in matrix of an ultra-high carbon sintered steel during heat treatment process

    Yuan-zhi Zhu; Zhe Zhu; Zhi-min Yin; Zhi-dong Xiang

    2009-01-01

    DTA, thermal expansion, XRD, and SEM were used to evaluate the effect of quenching temperature on the mechanical properties and microstructure of a novel sintered steel Fe-6Co-1Ni-5Cr-5Mo-1C. Lattice parameters and the mass fraction of carbon dissolved in the matrix of the steel quenched were investigated. It is discovered that the hardness of the steel increases with quench-ing temperature in the range of 840-900℃ and remains constant in the range of 900 to 1100℃. It decreases rapidly when the tem-perature is higher than 1100℃. The mass fraction of carbon dissolved in the matrix of the steel quenched at 840℃ is 0.38, but when the quenching temperature is increased to 1150℃, it increases to 0.98. The carbides formed during sintering are still present at grain boundaries and in the matrix of the steel quenched at low quenching temperatures, such as 840℃. When the quenching temperature is increased to 1150℃, most of the carbides at grain boundaries are dissolved with just a small amount of spherical M23C6 existing in the matrix of the quenched steel.

  15. Development of an optimized methodology for tensile testing of carbon steels in hydrogen environment

    Cuadros Fernández, Pau; Baró, M.D.

    2009-01-01

    The study was performed at OCAS, the Steel Research Centre of ArcelorMittal for the Industry market. The major aim of this research was to obtain an optimized tensile testing methodology with in-situ H-charging to reveal the hydrogen embrittlement in various high strength steels. The second aim of this study has been the mechanical characterization of the hydrogen effect on hight strength carbon steels with varying microstructure, i.e. ferrite-martensite and ferrite-bainite grades. The optima...

  16. Stages of austenitization of cold-worked low-carbon steel in intercritical temperature range

    Panov, D. O.; Simonov, Y. N.; Spivak, L. V.; Smirnov, A. I.

    2015-08-01

    Austenization processes in 10Kh3G3MF low-carbon steel in the initially cold-worked state are investigated during its continuous heating in an intercritical temperature range. The austenization of this steel has three stages, which is shown by dilatometry, differential scanning calorimetry, and transmission electron microscopy. The thermokinetic diagram of the austenite formation in 10Kh3G3MF steel is constructed. Critical points A c1 and A c2 and temperature ranges of austenite formation at every stage of the α → γ transformation at heating rates of 0.6-400 K/s are determined.

  17. Corrosion and Runoff Behavior of Carbon Steel in Simulated Acid Rain

    Baigang AN; Xueyuan ZHANG; Enhou HAN; Honxi LI

    2004-01-01

    Under the condition of simulated rain precipitation in the laboratory, with ElS and SEM observation, the effects of pH value of simulated rain on corrosion and runoff behavior of carbon steel A3 were studied. The corrosion rate of A3 steel increased and runoff action of rain precipitation on A3 steel surface was intensified with decreasing pH value, of simulated rainwater.The runoff and corrosion traces were formed along the flowing direction of rainwater, which appeared more apparently with decreasing pH value.

  18. Effects of LWR environments on fatigue life of carbon and low-alloy steels

    SME Boiler and Pressure Vessel Code provides construction of nuclear power plant components. Figure I-90 Appendix I to Section III of the Code specifies fatigue design curves for structural materials. While effects of environments are not explicitly addressed by the design curves, test data suggest that the Code fatigue curves may not always be adequate in coolant environments. This paper reports the results of recent fatigue tests that examine the effects of steel type, strain rate, dissolved oxygen level, strain range, loading waveform, and surface morphology on the fatigue life of A 106-Gr B carbon steel and A533-Gr B low-alloy steel in water

  19. Control of microbiological corrosion on carbon steel with sodium hypochlorite and biopolymer.

    Oliveira, Sara H; Lima, Maria Alice G A; França, Francisca P; Vieira, Magda R S; Silva, Pulkra; Urtiga Filho, Severino L

    2016-07-01

    In the present work, the interaction of a mixture of a biocide, sodium hypochlorite (NaClO), and a biopolymer, xanthan, with carbon steel coupons exposed to seawater in a turbulent flow regime was studied. The cell concentrations, corrosion rates, biomasses, and exopolysaccharides (EPSs) produced on the coupon surfaces with the various treatments were quantified. The corrosion products were evaluated using X-ray diffraction (XRD), and the surfaces of steels were analysed by scanning electron microscopy (SEM). The results indicated that xanthan and the hypochlorite-xanthan mixture reduced the corrosion rate of steel. PMID:26997238

  20. The Mechanism of High Ductility for Novel High-Carbon Quenching-Partitioning-Tempering Martensitic Steel

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

    2015-09-01

    In this article, a novel quenching-partitioning-tempering (Q-P-T) process was applied to treat Fe-0.6C-1.5Mn-1.5Si-0.6Cr-0.05Nb hot-rolled high-carbon steel and the microstructures including retained austenite fraction and the average dislocation densities in both martensite and retained austenite were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, respectively. The Q-P-T steel exhibits high strength (1950 MPa) and elongation (12.4 pct). Comparing with the steel treated by traditional quenching and tempering (Q&T) process, the mechanism of high ductility for high-carbon Q-P-T steel is revealed as follows. Much more retained austenite existing in Q-P-T steel than in Q&T one remarkably enhances the ductility by the following two effects: the dislocation absorption by retained austenite effect and the transformation-induced plasticity effect. Besides, lower dislocation density in martensite matrix produced by Q-P-T process plays an important role in the improvement of ductility. However, some thin plates of twin-type martensite embedded in dislocation-type martensite matrix in high-carbon Q-P-T steel affect the further improvement of ductility.

  1. Influence of boron on strain hardening behaviour and ductility of low carbon hot rolled steel

    Highlights: → Unique feature of low strain hardening exponent (n) with high total elongation has been discussed in industrially produced low carbon boron containing steel. → n has been correlated with the micro structural changes occurring during deformation of steel. → This feature of low n and high % elongation has potential for higher cold reducibility. → The work is being reported for the first time on industrially produced low carbon boron containing steel. - Abstract: The beneficial effect of boron on mechanical properties of low carbon Al-killed steel has been reported in recent past. However, the effect of boron on strain hardening exponent (n) and ductility has not been fully understood. This aspect has been discussed in present work. The results of mill trials with reference to n and ductility with boron added steel are compared to those for commercial grade. The lowering of 'n' with increased total elongation in boron bearing steel has been related to the microstructural evolution as a result of boron addition.

  2. Corrosion-resistant Foamed Cements for Carbon Steels

    Sugama T.; Gill, S.; Pyatina, T., Muraca, A.; Keese, R.; Khan, A.; Bour, D.

    2012-12-01

    The cementitious material consisting of Secar #80, Class F fly ash, and sodium silicate designed as an alternative thermal-shock resistant cement for the Enhanced Geothermal System (EGS) wells was treated with cocamidopropyl dimethylamine oxide-based compound as foaming agent (FA) to prepare numerous air bubble-dispersed low density cement slurries of and #61603;1.3 g/cm3. Then, the foamed slurry was modified with acrylic emulsion (AE) as corrosion inhibitor. We detailed the positive effects of the acrylic polymer (AP) in this emulsion on the five different properties of the foamed cement: 1) The hydrothermal stability of the AP in 200 and #61616;C-autoclaved cements; 2) the hydrolysis-hydration reactions of the slurry at 85 and #61616;C; 3) the composition of crystalline phases assembled and the microstructure developed in autoclaved cements; 4) the mechanical behaviors of the autoclaved cements; and, 5) the corrosion mitigation of carbon steel (CS) by the polymer. For the first property, the hydrothermal-catalyzed acid-base interactions between the AP and cement resulted in Ca-or Na-complexed carboxylate derivatives, which led to the improvement of thermal stability of the AP. This interaction also stimulated the cement hydration reactions, enhancing the total heat evolved during cement’s curing. Addition of AP did not alter any of the crystalline phase compositions responsible for the strength of the cement. Furthermore, the AP-modified cement developed the porous microstructure with numerous defect-free cavities of disconnected voids. These effects together contributed to the improvement of compressive-strength and –toughness of the cured cement. AP modification of the cement also offered an improved protection of CS against brine-caused corrosion. There were three major factors governing the corrosion protection: 1) Reducing the extents of infiltration and transportation of corrosive electrolytes through the cement layer deposited on the underlying CS

  3. Synergistic inhibition of carbon steel corrosion in seawater by cerium chloride and sodium gluconate

    Highlights: • Significant synergistic effect was determined for cerium and gluconate. • The mixture showed significant corrosion inhibition of carbon steel in seawater. • Predominant anodic inhibition mechanism was observed. • The presence of cerium ions incorporated in the protective layer was confirmed. - Abstract: In this research the effect of cerium (III) chloride heptahydrate (CC) and sodium gluconate (SG) on the corrosion inhibition of carbon steel C45 (1531) in natural seawater has been evaluated using electrochemical methods and scanning electron microscopy (SEM). The results show that substantial corrosion inhibition (94.98%) using CC and SG can be obtained in synergistic manner. Surface analysis confirmed the presence of cerium ions incorporated in the protective layer of carbon steel specimen. SG acts predominantly as anodic inhibitor whereas CC acts as a mixed type inhibitor. Using both inhibitors predominant mechanism of anodic inhibition is observed

  4. Investigation on Preferential Corrosion of Welded Carbon Steel Under Flowing Conditions by EIS

    Alawadhi, K.; Aloraier, A. S.; Joshi, S.; Alsarraf, J.; Swilem, S.

    2013-08-01

    Carbon steels are used extensively in construction of oil and gas pipes but they exhibit poor corrosion-resistance properties because of internal corrosion. In this research, a rotating cylinder electrode apparatus was designed so that electrodes machined from the weld metal, heat-affected zone, and parent material of a welded X65 pipeline steel could be tested in high shear stress conditions using electromechanical impedance spectroscopy. The aim was to investigate the cause of the severe localized corrosion that sometimes occurs at welds in carbon steel pipelines carrying hydrocarbons and inhibited brine solutions saturated with carbon dioxide. It was concluded that the surface films play an important role in effective inhibition, and this inhibition is more effective on a clean surface rather than on a precorroded one.

  5. Carbon steel protection in G.S. [Girldler sulphide] plants: Pt. 7

    In order to protect carbon steel towers and piping of a GS experimental heavy water plant against corrosion produced by the action of aqueous solutions of hydrogen sulphide, a method, elsewhere published, was developed. Carbon steel exposed to saturated aqueous solutions of hydrogen sulphide forms iron sulphide scales. In oxygen free solutions, evolution of corrosion follows the sequence mackinawite → cubic ferrous sulphide → troilite → pyrrotite → pyrite. Scales formed by pyrrotite and pyrite are the most protective layers (these are obtained at 130 deg C, 2 MPa for a period of 14 days). During a plant shutdown procedures, the carbon steel protected with those scales is exposed to water and highly humid air; under such conditions oxidation is unavoidable. Later, treatment in plant conditions does not regenerate scales because the composition of regenerated scales involves more soluble iron sulphides such as mackinawite and troilite. Therefore, it is not recommendable to expose the protective scales to atmospherical conditions. (Author)

  6. The effect of environmental variables on atmospheric corrosion of carbon steel in Shenyang

    WANG Chuan; WANG ZhenYao; KE Wei

    2009-01-01

    A study was carried out in order to investigate the effect of contaminants and meteorological variables on the rust layer of carbon steel exposed in Shenyang urban atmosphere. Seven kinds of contaminants and twelve kinds of meteorological parameters were also registered in order to correlate the data with respect to corrosion rate and the stepwise multiple regression analysis was carried out in order to obtain the best regression model. The sum of rainfall time as well as sunshine time and the concentration of H_2S could stimulate initial atmospheric corrosion of carbon steel. The initial atmospheric corrosion kinetics of carbon steel was observed to follow the cubic equation. The corrosion products were analyzed by XRD and the transformation of phases in different periods was discussed.

  7. Ni-W coatings electrodeposited on carbon steel: Chemical composition, mechanical properties and corrosion resistance

    Highlights: → Hard, ductile and adherent nanostructured Ni-W coatings on carbon steel. → New procedures for achieving deposits by current pulse techniques. → Current pulse frequency was the dominant factor to define coating characteristics. → Ni-W coatings protect the carbon steel from corrosion induced by sulphate anions. - Abstract: Hard, ductile and adherent nanostructured Ni-W coatings were electrodeposited on carbon steel from electrolyte solutions containing sodium tungstate, nickel sulfate and sodium citrate, using different current pulse programs. Current pulse frequency was the dominant factor to define chemical composition, grain size, thickness and hardness. According to the electrodeposition conditions the deposited coatings showed 15-30 at% W, the grain size ranged from 65 to 140 nm, and the hardness varied from 650 to 850 Hv. Tungsten carbide also present in the coating contributed to its hardness. The corrosion resistance of the Ni-W coated steel was tested by potentiodynamic polarization in a neutral medium containing sulphate ions. The Ni-W coating protected the carbon steel from localized corrosion induced by sulphate anions.

  8. The effect of additional high dose carbon implantation on the tribological properties of titanium implanted steel

    The tribological properties and the structural changes of hardened steel implanted with titanium followed by carbon were investigated as a function of additional carbon dose. The dose of Ti was 5.1017 Ti cm-2 and the additional C doses were 0, 4.1017, 8.1017 and 1.2.1018 Ccm-2. After Ti implantation, the steel surface transformed to a Fe-Ti-C ternary amorphous phase. Additional implantation of carbon to a dose of 4.1017 Ccm-2 produced fine TiC precipitates dispersed in the ternary amorphous matrix. When the additional C dose exceeded 8.1017 Ccm-2, very fine graphite precipitates appeared in the ternary amorphous phase. The steel surface with very fine graphite precipitates exhibited superior tribological properties. The benefits provided by additional high dose carbon implantation are considered as follows: strengthening of the amorphous phase, thickening of the modified layer, dispersion strengthening of the implanted layer by very fine graphite precipitates and lubrication effect by graphite particles. Comparing the friction properties of Ti+C implanted steel with that of C implanted steel, the role of Ti implantation is to reduce the friction of the surface during sliding and the role of C implantation is to increase the lifetime of the surface against wear. (orig.)

  9. Electrochemical behavior and anticorrosion properties of modified polyaniline dispersed in polyvinylacetate coating on carbon steel

    Conducting polyaniline (Pani) was prepared in the presence of methane sulfonic acid (MeSA) as dopant by chemical oxidative polymerization. The Pani-MeSA polymer was characterized by FT-IR, UV-vis, X-ray diffraction (XRD) and impedance spectroscopy. The polymer was dispersed in polyvinylacetate and coated on carbon steel samples by a dipping method. The electrochemical behavior and anticorrosion properties of the coating on carbon steel in 3% NaCl were investigated using open-circuit potential (OCP) versus time of exposure, and electrochemical techniques including electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and cyclic voltammetry (CV). During initial exposure, the OCP dropped about 0.35 V and the interfacial resistance increased several times, indicating a certain reduction of the polymer and oxidation of the steel surface. Later the OCP shifted to the noble direction and remained at a stable value during the exposure up to 60 days. The EIS monitoring also revealed the initial change and later stabilization of the coating. The stable high OCP and low coating impedance suggest that the conducting polymer maintains its oxidative state and provides corrosion protection for carbon steel throughout the investigated period. The polarization curves and CV show that the conducting polymer coating induces a passive-like behavior and greatly reduces the corrosion of carbon steel

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

    J. Zrnik

    2009-07-01

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

  11. Development of a ferritic low-carbon steel for elevated temperature service

    A readily weldable 12Cr-2Mo steel with excellent creep-rupture characteristics has been developed. The outstanding weldability of the new steel results from its low carbon content, nominally 0.075%, and the high creep resistance of the steel is due to its martensitic microstructure strengthened with dispersed austenite. In addition to 12% Cr and 2% Mo the steel contains 0.6% Mn, 6% Ni, 0.25% V, 0.1% Nb, and 0.04% N. The tempering response of the new steel is essentially flat for a wide range of tempering conditions. When tempered for 1 hour at 7000C (12900F), the steel exhibits room temperature yield and tensile strengths of 790 and 1080 MPa (115 and 156 ksi), respectively, with 15% elongation and 64% area reduction. Elevated temperature tensile properties at 6490C (12000F) include yield and tensile strengths of 345 and 405 MPa (50 and 58 ksi), respectively, with 32% elongation and 89% area reduction. The steel exhibits 100% ductile fracture in room temperature Charpy V-notch (CVN) impact tests, with a typical impact energy of 135 J (100 ft-lb). In creep-rupture tests at 6490C (12000F) the steel exhibits rupture strengths and minimum creep rates at least comparable to those of Type 316 stainless steel. The steel is easily hot worked and is weldable without the need for pre-heat or post-weld stress relief. The combination of very high strength, excellent weldability, and stable, predominantly ferritic microstructure makes this steel an attractive candidate for use in nuclear energy applications

  12. Effect of magnetite as a corrosion product on the corrosion of carbon steel overpack

    It is necessary to clear the effects of corrosion products on the corrosion life time of carbon steel overpack for geological isolation of high-level radioactive waste (HLW). Especially, it is important to understand the effects of magnetite because magnetite as a simulated corrosion product is reported to accelerate the corrosion rate of carbon steel. In this study, corrosion tests to reproduce the acceleration of corrosion due to magnetite was performed and the mechanism of the acceleration was investigated to evaluate the effects of magnetite as a corrosion product. Based on the results of experiments, following conclusions are obtained; (1) Magnetite powder accelerates the corrosion rate of carbon steel. The main reaction of corrosion under the presence of magnetite is the reduction of Fe(III) in magnetite to Fe(II), but the reaction of hydrogen generation is also accelerated. The contribution of hydrogen generation reaction was estimated to be about 30% in the total corrosion reaction based on the experimental result of immersion test under the presence of magnetite. (2) Actual corrosion products containing magnetite generated by the corrosion of carbon steel protect the metal from the propagation of corrosion. The corrosion depth of carbon steel overpack due to magnetite was estimated to be about 1 mm based on the results of experiments. Even if the effect of magnetite is taken into the assessment of corrosion lifetime of overpack, total corrosion depth in 1000 years is estimated to be 33 mm, which is smaller than the corrosion allowance of 40 mm described in the second progress report on research and development for the geological disposal of HLW in Japan. It was concluded that the effect of magnetite on the corrosion life time of carbon steel overpack is negligible. (author)

  13. Characterization of carbon ion implantation induced graded microstructure and phase transformation in stainless steel

    Austenitic stainless steel 316L is ion implanted by carbon with implantation fluences of 1.2 × 1017 ions-cm− 2, 2.4 × 1017 ions-cm− 2, and 4.8 × 1017 ions-cm− 2. The ion implantation induced graded microstructure and phase transformation in stainless steel is investigated by X-ray diffraction, X-ray photoelectron spectroscopy and high resolution transmission electron microscopy. The corrosion resistance is evaluated by potentiodynamic test. It is found that the initial phase is austenite with a small amount of ferrite. After low fluence carbon ion implantation, an amorphous layer and ferrite phase enriched region underneath are formed. Nanophase particles precipitate from the amorphous layer due to energy minimization and irradiation at larger ion implantation fluence. The morphology of the precipitated nanophase particles changes from circular to dumbbell-like with increasing implantation fluence. The corrosion resistance of stainless steel is enhanced by the formation of amorphous layer and graphitic solid state carbon after carbon ion implantation. - Highlights: • Carbon implantation leads to phase transformation from austenite to ferrite. • The passive film on SS316L becomes thinner after carbon ion implantation. • An amorphous layer is formed by carbon ion implantation. • Nanophase precipitate from amorphous layer at higher ion implantation fluence. • Corrosion resistance of SS316L is improved by carbon implantation

  14. 75 FR 75455 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Final Results of Full...

    2010-12-03

    ... (``IF'')) steels, high strength low alloy (``HSLA'') steels, and the substrate for motor lamination... titanium and/or niobium added to stabilize carbon and nitrogen elements. HSLA steels are recognized as...: Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, 64 FR 38741, 38744 (July...

  15. 76 FR 36081 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil and Japan: Revocation of the...

    2011-06-21

    ... (``IF'')) steels, high strength low alloy (``HSLA'') steels, and the substrate for motor lamination... titanium and/or niobium added to stabilize carbon and nitrogen elements. HSLA steels are recognized as... Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia, 76 FR 34101...

  16. Stress corrosion cracking in low carbon stainless steel components in BWRs

    In recent years, numbers of SCC have occurred in core shrouds and primary loop recirculation piping made of low carbon stainless steels that had been recognized to be an SCC-resistant material. These incidents resulted in long-term shutdown of Japanese boiling water reactors and have drawn social as well as technical interests. This paper will provide an introductory review on (1) background of SCC observed in low carbon stainless steel components in BWRs, (2) characteristics of SCC in core shrouds and PLR piping, (3) structural integrity evaluation, (4) SCC mitigation techniques, (5) SCC mechanism and (6) research topics that should be covered regarding these issues. (author)

  17. Effect of Rare Earths on Corrosion Resisting Properties of Carbon-Manganese Clean Steels

    郭锋; 林勤; 孙学义

    2004-01-01

    Electrochemistry experiments were made on carbon-manganese clean steel with rare earths Ce and La respectively to observe corrosion parameters such as corrosion current icorr, and characteristic potential of pitting Eb. The results indicate that the rare earths have effect on corrosion resisting properties of carbon-manganese clean steel, and the optimum contents of La is about 0.011% (mass fraction) and Ce about 0.014% (mass fraction) respectively. The change of corrosion resistance is related to the action of rare earths on microstructure and effect on surface state of samples in the process of polarization.

  18. Development of corrosion rate measuring apparatus for carbon steel under reducing environment

    In order to monitor the corrosion rate of carbon steel under deep under-ground environment which is depleted with oxygen, the corrosion rate measuring apparatus using the hydrogen permeation current was developed. Inner surface of the carbon steel monitor electrode made of beverage can was coated with Ni or Pd-Ni plating, which was used as the hydrogen detecting electrode. Corrosion rate which was estimated from hydrogen permeation current well consisted with literature data. Corrosion rate in acidic solution at pH 2 after long time elapsed. (author)

  19. Mechanical Properties of Cold-Drawn Low Carbon Steel for Nail Manufacture: Experimental Observation

    N.A. Raji; O.O. Oluwole

    2013-01-01

    The objective of this study is to investigate the influence of service situation on the mechanical properties of plain nails manufactured from low carbon steel. The influence of the degree of cold drawing on the mechanical properties and strain hardening of the material is investigated by tensile test experimentation. The stress-strain relationships of the cold-drawn low carbon steel were investigated over the 20, 25, 40 and 55% degree of drawn deformation for the manufacture of 4, 3, 2½ and ...

  20. Corrosion Behaviour of Nickel Plated Low Carbon Steel in Tomato Fluid

    Oluleke OLUWOLE; Oluwadamilola OLAWALE

    2010-01-01

    This research work investigated the corrosion resistance of nickel plated low carbon steel in tomato fluid. It simulated the effect of continuous use of the material in a tomato environment where corrosion products are left in place. Low carbon steel samples were nickel electroplated at 4V for 20, 25, 30 and 35 mins using Watts solution.The plated samples were then subjected to tomato fluid environment for for 30 days. The electrode potentials mV (SCE) were measured every day. Weight loss was...

  1. 77 FR 21968 - Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's Republic of...

    2012-04-12

    ... International Trade Administration Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the... countervailing duty order on seamless carbon and alloy steel standard, line, and pressure pipe from the People's... Antidumping and Countervailing Duty Administrative Reviews and Request for Revocation in Part, 76 FR...

  2. 75 FR 29972 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe from the People's...

    2010-05-28

    ... Determination, 75 FR 22372 (April 28, 2010) (``Preliminary Determination''). On May 3, 2010, Tianjin Pipe (Group... International Trade Administration Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe... antidumping duty investigation of certain seamless carbon and alloy steel standard, line, and pressure...

  3. 75 FR 6183 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe from the People's...

    2010-02-08

    ... investigation on certain seamless carbon and alloy steel standard, line, and pressure pipe from the People's Republic of China. See Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's Republic of China: Initiation of Antidumping Duty Investigation, 74 FR 52744 (October 14,...

  4. 75 FR 57449 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe from the People's...

    2010-09-21

    ... International Trade Administration Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe... determined that certain seamless carbon and alloy steel standard, line, and pressure pipe from the People's..., in Part, and Postponement of Final Determination, 75 FR 22372 (April 28, 2010)...

  5. 76 FR 7151 - Certain Carbon Steel Butt-Weld Pipe Fittings From Brazil, Japan, Taiwan, Thailand, and the People...

    2011-02-09

    ... Order; Certain Carbon Steel Butt-Weld Pipe Fittings from Brazil, 51 FR 45152 (December 17, 1986... Fair Value; Certain Carbon Steel Butt-Weld Pipe Fittings From the People's Republic of China, 57 FR... of 1930, as amended (the Act). See Initiation of Five-Year (``Sunset'') Review, 75 FR 60731...

  6. 75 FR 80455 - Certain Hot-Rolled Carbon Steel Flat Products From India: Amended Final Results of Countervailing...

    2010-12-22

    ..., 73 FR 40295 (July 14, 2008) (Final Results), and accompanying Issues and Decision Memorandum (``I&D... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From India: Amended Final... administrative review of the countervailing duty order on certain hot-rolled carbon steel flat products...

  7. 75 FR 59689 - Certain Hot-Rolled Carbon Steel Flat Products From India: Notice of Court Decision Not in Harmony...

    2010-09-28

    ... Administrative Review, 73 FR 40295 (July 14, 2008) (Final Results), and accompanying Issues and Decision... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From India: Notice of Court... administrative review of the countervailing duty order on certain hot-rolled carbon steel flat products...

  8. 78 FR 15703 - Certain Hot-Rolled Carbon Steel Flat Products From India, Indonesia, the People's Republic of...

    2013-03-12

    ...'') Review, 77 FR 66439 (November 5, 2012). The Department received a notice of intent to participate from... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From India, Indonesia, the... the second sunset reviews of the antidumping duty orders on certain hot-rolled carbon steel...

  9. 75 FR 55742 - Certain Hot-Rolled Carbon Steel Flat Products from India: Extension of Time Limit for Preliminary...

    2010-09-14

    ... FR 4770 ] (January 29, 2010) (``Initiation Notice''). The current deadline for the preliminary... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products from India: Extension of Time... antidumping duty administrative review of certain hot- rolled carbon steel flat products from India for...

  10. 77 FR 14341 - Certain Hot-Rolled Carbon Steel Flat Products From Taiwan: Notice of Rescission of Antidumping...

    2012-03-09

    ... Antidumping and Countervailing Duty Administrative Reviews and Request for Revocation in Part, 76 FR 82268... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From Taiwan: Notice of... an administrative review of the antidumping duty order on certain hot-rolled carbon steel...

  11. 75 FR 81968 - Circular Welded Carbon Quality Steel Pipe From the People's Republic of China: Rescission of...

    2010-12-29

    ... International Trade Administration Circular Welded Carbon Quality Steel Pipe From the People's Republic of China... circular welded carbon quality steel pipe (``CWP'') from the People's Republic of China (``PRC''). This... Order, Finding, or Suspended Investigation; Opportunity To Request Administrative Review, 75 FR...

  12. 78 FR 55057 - Corrosion-Resistant Carbon Steel Flat Products from the Republic of Korea: Preliminary Results of...

    2013-09-09

    ... International Trade Administration Corrosion-Resistant Carbon Steel Flat Products from the Republic of Korea... antidumping duty order on corrosion-resistant carbon steel flat products (CORE) from the Republic of Korea... Requests for Revocation in Part, 77 FR 59168 (September 26, 2012). \\2\\ The period of review (POR) ends...

  13. 75 FR 22555 - Certain Cut-to-Length Carbon-Quality Steel Plate from the Republic of Korea: Rescission of...

    2010-04-29

    ... International Trade Administration Certain Cut-to-Length Carbon-Quality Steel Plate from the Republic of Korea... administrative review of the antidumping duty order on certain cut-to-length carbon-quality steel plate (CTL... Revocation in Part, 75 FR 15679, 15681 (March 30, 2010) (Initiation Notice). The two companies identified...

  14. 77 FR 25404 - Certain Hot-Rolled Carbon Steel Flat Products From India: Rescission of Antidumping Duty...

    2012-04-30

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products From India: Rescission of... request an administrative review of the antidumping duty order on certain hot- rolled carbon steel flat... FR 74773, 74774 (December 1, 2011). On December 30, 2011, and January 3, 2012, Nucor Corporation...

  15. 77 FR 36256 - Circular Welded Carbon-Quality Steel Pipe From India: Postponement of Final Determination of...

    2012-06-18

    ... International Trade Administration Circular Welded Carbon-Quality Steel Pipe From India: Postponement of Final... investigation on circular welded carbon- quality steel pipe from India.\\1\\ On June 1, 2012, the Department... Vietnam: Initiation of Antidumping Duty Investigations, 76 FR 72164 (November 22, 2011). \\2\\ See...

  16. 76 FR 4291 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Partial Rescission of...

    2011-01-25

    ... International Trade Administration Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea... administrative review of the countervailing duty order on corrosion- resistant carbon steel flat products from... FR 60078 (September 29, 2010) (Initiation). As a result of withdrawals of request for review, we...

  17. 77 FR 301 - Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea: Institution of Five-Year...

    2012-01-04

    ... corrosion-resistant carbon steel flat products from Germany and Korea (72 FR 7009). The Commission is now... part 207), as most recently amended at 74 FR 2847 (January 16, 2009). \\1\\ No response to this request...-resistant carbon steel flat products from Korea (58 FR 43752). On August 19, 1993, Commerce...

  18. 76 FR 77775 - Corrosion-Resistant Carbon Steel Flat Products from the Republic of Korea: Extension of Time...

    2011-12-14

    ... FR 54209 (August 31, 2011) (``Preliminary Results''). The final results were originally due no later... International Trade Administration Corrosion-Resistant Carbon Steel Flat Products from the Republic of Korea... countervailing duty order on corrosion-resistant carbon steel flat products from the Republic of Korea...

  19. Influence of carbon steel and its corrosion products on the leaching of elements from a simulated waste glass. Research document

    The influence of carbon steel and its corrosion products on leaching of elements from simulated high level radioactive waste glass (P0798) has been investigated in batch-type experiments of up to one year at 25±3degC under argon atmosphere (-1. For each series, a polished glass cube or glass particles were immersed in double distilled deoxidized water with powder of carbon steel or of magnetite, as an assumed carbon steel corrosion product, in the ratio of 10 gram carbon steel (or magnetite) to 1 litter of water. Normalized mass losses of Si, B, Na and Cs in the system of glass-carbon steel-water and of glass-magnetite-water apparently increased compared with those in the glass-water system. The glass dissolution could be accelerated by increasing hydroxyl ion resulting from hydrolysis of carbon steel or of magnetite. The pH values of leachate become eventually almost constant and it indicates that a steady state has been attained between these hydroxyl ion releases and its consumption, which is a disruption process of siloxane bond by hydroxyl ion in solution. The influence of carbon steel and its corrosion products on leaching of elements from the waste glass can be predominantly attributed to a pH effect in this experiment. The increase of glass corrosion rate, however, could be assessed within one order as an influence of the existence of carbon steel and/or its corrosion products. (author)

  20. 76 FR 19788 - Carbon Steel Butt-Weld Pipe Fittings From Brazil, China, Japan, Taiwan, and Thailand

    2011-04-08

    ... determined on January 4, 2011 that it would conduct expedited reviews (76 FR 5205). The Commission... COMMISSION Carbon Steel Butt-Weld Pipe Fittings From Brazil, China, Japan, Taiwan, and Thailand... U.S.C. 1675(c)), that revocation of the antidumping duty orders on carbon steel butt-weld...

  1. 76 FR 57020 - Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Notice of Partial Rescission of...

    2011-09-15

    ... Antidumping and Countervailing Duty Administrative Reviews and Request for Revocation in Part, 76 FR 37781... International Trade Administration Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Notice of Partial... welded carbon steel pipes and tubes from Taiwan. The review covers eight firms. Based on a withdrawal...

  2. 75 FR 3896 - Certain Welded Carbon Steel Pipe and Tube from Turkey: Extension of Time Limit for Preliminary...

    2010-01-25

    ... International Trade Administration Certain Welded Carbon Steel Pipe and Tube from Turkey: Extension of Time... and Countervailing Duty Administrative Reviews and Request for Revocation in Part, 74 FR 30052 (June... initiation of the administrative review of the antidumping duty order on certain welded carbon steel pipe...

  3. 76 FR 71938 - Circular Welded Carbon Steel Pipes and Tubes From Thailand: Extension of Time Limit for...

    2011-11-21

    ... Administrative Reviews, 76 FR 23545, 23546 (April 27, 2011). This review covers two producers/exporters of the... International Trade Administration Circular Welded Carbon Steel Pipes and Tubes From Thailand: Extension of Time... the antidumping duty order on circular welded carbon steel pipes and tubes from Thailand for...

  4. 77 FR 41967 - Certain Circular Welded Carbon Steel Pipes and Tubes From India, Thailand, and Turkey; Certain...

    2012-07-17

    ... Review, 75 FR 69626, 69627 (November 15, 2010). Thailand--Welded Carbon Steel Pipe and Tube (A-549-502... remand. See Scope Rulings, 58 FR 27542 (May 10, 1993). Turkey--Welded Carbon Steel Pipe and Tube (A-489... Initiation of Five-Year (``Sunset'') Review, 76 FR 38613 (July 1, 2011). \\2\\ See Certain Circular...

  5. 77 FR 32562 - Circular Welded Carbon-Quality Steel Pipe From India: Preliminary Determination of Sales at Less...

    2012-06-01

    ... FR at 72164-5. On December 9, 2011, we received comments from a UAE producer named Universal Tube and...: Circular Welded Carbon Quality Steel Pipe from the People's Republic of China, 73 FR 31970 (June 5, 2008... Duty Order; Certain Welded Carbon Steel Standard Pipes and Tubes from India, 51 FR 17384 (May 12,...

  6. 77 FR 2511 - Certain Welded Carbon Steel Pipe and Tube From Turkey: Extension of Time Limit for Preliminary...

    2012-01-18

    ... International Trade Administration Certain Welded Carbon Steel Pipe and Tube From Turkey: Extension of Time... administrative review of the antidumping duty order on certain welded carbon steel pipe and tube from Turkey... Duty Administrative Reviews and Request for Revocation in Part, 76 FR 37781 (June 28, 2011)....

  7. 76 FR 3083 - Certain Welded Carbon Steel Pipe and Tube From Turkey: Extension of Time Limit for Preliminary...

    2011-01-19

    ... International Trade Administration Certain Welded Carbon Steel Pipe and Tube From Turkey: Extension of Time... administrative review of the antidumping duty order on certain welded carbon steel pipe and tube from Turkey... Duty Administrative Reviews and Requests for Revocation in Part, 75 FR 37759 (June 30, 2010)....

  8. 75 FR 63439 - Certain Welded Carbon Steel Standard Pipes and Tubes From India: Extension of the Final Results...

    2010-10-15

    ... Results of Antidumping Duty Administrative Review, 75 FR 33578 (June 14, 2010). The review covers the... International Trade Administration Certain Welded Carbon Steel Standard Pipes and Tubes From India: Extension of... the administrative review of the antidumping duty order on certain welded carbon steel standard...

  9. 77 FR 32508 - Circular Welded Carbon Steel Pipes and Tubes From Turkey: Notice of Preliminary Results of...

    2012-06-01

    ... Order; Welded Carbon Steel Standard Pipe and Tube Products From Turkey, 51 FR 17784 (May 15, 1986..., 76 FR 33204, 33208 (June 8, 2011), unchanged in Certain Welded Carbon Steel Pipe and Tube From Turkey... Tube from Turkey; Notice of Preliminary Results of Antidumping Duty Administrative Review, 76 FR...

  10. 76 FR 78313 - Circular Welded Carbon-Quality Steel Pipe From India, Oman, the United Arab Emirates, and Vietnam

    2011-12-16

    ... COMMISSION Circular Welded Carbon-Quality Steel Pipe From India, Oman, the United Arab Emirates, and Vietnam... United Arab Emirates, and Vietnam of circular welded carbon- quality steel pipe, provided for in... October 26, 2011, a petition was filed with the Commission and Commerce by Allied Tube and Conduit,...

  11. 76 FR 63902 - Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Final Results of Antidumping Duty...

    2011-10-14

    ... Welded Carbon Steel Pipes and Tubes From Taiwan, 76 FR 33210 (June 8, 2011) (Preliminary Results). This... Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Antidumping Duty Order, 49 FR 19369 (May 7, 1984... section 773(b) of the Tariff Act of 1930, as amended (the Act). See Preliminary Results, 76 FR at...

  12. 77 FR 6542 - Certain Welded Carbon Steel Standard Pipe and Tube From Turkey: Notice of Final Rescission of...

    2012-02-08

    ... International Trade Administration Certain Welded Carbon Steel Standard Pipe and Tube From Turkey: Notice of... of the countervailing duty (CVD) order on certain welded carbon steel pipe and tube from Turkey for... FR 11197 (March 1, 2011). On March 30, 2011, we received a letter from Erbosan Erciyas Boru Sanayi...

  13. 77 FR 55807 - Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Notice of Partial Rescission of...

    2012-09-11

    ... Reviews and Request for Revocation in Part, 77 FR 40565 (July 10, 2012). On August 15, 2012, the... International Trade Administration Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Notice of Partial... welded carbon steel pipes and tubes from Taiwan. The review covers four respondents. Based on...

  14. 76 FR 78886 - Certain Welded Carbon Steel Standard Pipe and Tube From Turkey: Intent To Rescind Countervailing...

    2011-12-20

    ... International Trade Administration Certain Welded Carbon Steel Standard Pipe and Tube From Turkey: Intent To... the countervailing duty (CVD) order on certain welded carbon steel pipe and tube from Turkey. See... Administrative Review, 76 FR 11197 (March 1, 2011). On March 30, 2011, we received a letter from Erbosan...

  15. 75 FR 68327 - Certain Welded Carbon Steel Standard Pipes and Tubes From India: Rescission of Antidumping Duty...

    2010-11-05

    ... and Requests for Revocation in Part, 75 FR 37759 (June 30, 2010). Based on various requests for review... International Trade Administration Certain Welded Carbon Steel Standard Pipes and Tubes From India: Rescission... certain welded carbon steel standard pipes and tubes from India. The period of review is May 1,...

  16. 75 FR 33262 - Certain Welded Carbon Steel Pipe and Tube from Turkey: Notice of Preliminary Results of...

    2010-06-11

    ... and Tube From Turkey, 74 FR 6368 (February 9, 2009), unchanged in Certain Welded Carbon Steel Pipe and Tube from Turkey: Notice of Final Results of Antidumping Duty Administrative Review, 74 FR 22883 (May... International Trade Administration Certain Welded Carbon Steel Pipe and Tube from Turkey: Notice of...

  17. 78 FR 63450 - Carbon and Certain Alloy Steel Wire Rod From Brazil, Indonesia, Mexico, Moldova, Trinidad and...

    2013-10-24

    ... Act. See Initiation of Five-Year (``Sunset'') Reviews, 78 FR 33063 (June 3, 2013) (``Notice of... International Trade Administration, Carbon and Certain Alloy Steel Wire Rod From Brazil, Indonesia, Mexico... on carbon and certain alloy steel wire rod (``wire rod'') from Brazil, Indonesia, Mexico,...

  18. 75 FR 18152 - Certain Hot-Rolled Carbon Steel Flat Products from India: Extension of Time Limit for Final...

    2010-04-09

    ... International Trade Administration Certain Hot-Rolled Carbon Steel Flat Products from India: Extension of Time...: Preliminary Results of Countervailing Duty Administrative Review, 75 FR 1496 (January 11, 2010). Therefore... countervailing duty order on certain hot- rolled carbon steel flat products from India covering the...

  19. Stress corrosion cracking tests on electron beam welded carbon steel specimens in carbonate-bicarbonate solution

    Stress corrosion cracking tests have been performed on tapered carbon steel test pieces containing electron beam welds with a view to defining susceptibility to such cracking in a carbonate-bicarbonate solution at 90 C and an appropriate electrode potential. The tests involved applying cyclic loads to the specimens and it is shown that the threshold stress for cracking reduces linearly with increase in the magnitude of the cyclic load component. Extrapolation of these trends to zero fluctuating stress indicates static load threshold stresses in the vicinity of the yield stress (i.e. about 300 N/mm2 for parent plate without a weld, 400 N/mm2 for specimens with welds on one side only and 600 N/mm2 for specimens having welds penetrating through the thickness of the specimen). The averages of the maximum crack velocities observed were least for parent plate material and greatest for weld metal, the former being essentially intergranular in morphology and the latter mostly transgranular, with heat affected zone material being intermediate between these extremes. (author)

  20. The effect of oil on carbon dioxide corrosion inhibition on carbon steel - potential for improved corrosion protection

    Foss, Martin Smedstad

    2009-07-01

    The search for robust and cost efficient ways to prevent internal corrosion of carbon steel piping and equipment in oil and gas production and transportation has lead to the development of highly sophisticated CO{sub 2} corrosion inhibitor products. This thesis studies oil wetting and corrosion inhibitor performance on bare steel and steel with corrosion product deposits on the surface, in the presence of a refined, low aromatic hydrocarbon oil. Three surfactants were used in the experiments; two commercial inhibitor base chemicals; an oleic imidazoline salt (OI) and a phosphate ester (PE), and cetyl trimethyl ammonium bromide (CTAB), a well characterized quaternary ammonium compound. Adsorption characteristics of the inhibitors on corroding iron and FeCO{sub 3} particles were also studied. Polarization resistance (PR) and electrochemical impedance spectroscopy (EIS) techniques were used to study the effect of the oil on the performance of the inhibitors. The performance testing was done on corroding carbon steel without any surface deposits and on carbon steel with either ferrous carbonate (FeCO{sub 3}) or ferric corrosion products on the surface. The results showed that the addition of oil in the inhibitor tests had a significant, positive effect on the performance of the two commercial corrosion inhibitors; decrease in corrosion rate of about one order of magnitude compared to the rate without oil was found. Based on the EIS data it was concluded that the improved performance was caused by a modification of the inhibitor film and not the formation of a macroscopic oil film on the steel surface. Indications of oil wetting of the steel surface were only found when ferric corrosion products were present and OI was used as the inhibitor. No such effects were seen on bare steel or on FeCO{sub 3} covered surfaces. Contact angle measurements and dispersion tests were used to investigate the effect of the inhibitors on the wettability of the three types of surfaces when

  1. The effect of oil on carbon dioxide corrosion inhibition on carbon steel - potential for improved corrosion protection

    The search for robust and cost efficient ways to prevent internal corrosion of carbon steel piping and equipment in oil and gas production and transportation has lead to the development of highly sophisticated CO2 corrosion inhibitor products. This thesis studies oil wetting and corrosion inhibitor performance on bare steel and steel with corrosion product deposits on the surface, in the presence of a refined, low aromatic hydrocarbon oil. Three surfactants were used in the experiments; two commercial inhibitor base chemicals; an oleic imidazoline salt (OI) and a phosphate ester (PE), and cetyl trimethyl ammonium bromide (CTAB), a well characterized quaternary ammonium compound. Adsorption characteristics of the inhibitors on corroding iron and FeCO3 particles were also studied. Polarization resistance (PR) and electrochemical impedance spectroscopy (EIS) techniques were used to study the effect of the oil on the performance of the inhibitors. The performance testing was done on corroding carbon steel without any surface deposits and on carbon steel with either ferrous carbonate (FeCO3) or ferric corrosion products on the surface. The results showed that the addition of oil in the inhibitor tests had a significant, positive effect on the performance of the two commercial corrosion inhibitors; decrease in corrosion rate of about one order of magnitude compared to the rate without oil was found. Based on the EIS data it was concluded that the improved performance was caused by a modification of the inhibitor film and not the formation of a macroscopic oil film on the steel surface. Indications of oil wetting of the steel surface were only found when ferric corrosion products were present and OI was used as the inhibitor. No such effects were seen on bare steel or on FeCO3 covered surfaces. Contact angle measurements and dispersion tests were used to investigate the effect of the inhibitors on the wettability of the three types of surfaces when they were exposed to

  2. Does carbonation of steel slag particles reduce their toxicity? An in vitro approach.

    Ibouraadaten, Saloua; van den Brule, Sybille; Lison, Dominique

    2015-06-01

    Mineral carbonation can stabilize industrial residues and, in the steel industry, may contribute to simultaneously valorize CO2 emissions and slag. We hypothesized that, by restricting the leaching of metals of toxicological concern such as Cr and V, carbonation can suppress the toxicity of these materials. The cytotoxic activity (WST1 assay) of slag dusts collected from a stainless and a Linz-Donawitz (LD) steel plant, before and after carbonation, was examined in J774 macrophages. The release of Cr, V, Fe, Mn and Ni was measured after incubation in artificial lung fluids mimicking the extracellular and phagolysosomal milieu to which particles are confronted after inhalation. LD slag had the higher Fe, Mn and V content, and was more cytotoxic than stainless steel slag. The cytotoxic activity of LD but not of stainless dusts was reduced after carbonation. The cytotoxic activity of the dusts toward J774 macrophages necessitated a direct contact with the cells and was reduced in the presence of inhibitors of phagocytosis (cytochalasin D) or phagolysosome acidification (bafilomycin), pointing to a key role of metallic constituents released in phagolysosomes. This in vitro study supports a limited reduction of the cytotoxic activity of LD, but not of stainless, steel dusts upon carbonation. PMID:25735930

  3. Factors affecting stress assisted corrosion cracking of carbon steel under industrial boiler conditions

    Yang, Dong

    Failure of carbon steel boiler tubes from waterside has been reported in the utility boilers and industrial boilers for a long time. In industrial boilers, most waterside tube cracks are found near heavy attachment welds on the outer surface and are typically blunt, with multiple bulbous features indicating a discontinuous growth. These types of tube failures are typically referred to as stress assisted corrosion (SAC). For recovery boilers in the pulp and paper industry, these failures are particularly important as any water leak inside the furnace can potentially lead to smelt-water explosion. Metal properties, environmental variables, and stress conditions are the major factors influencing SAC crack initation and propagation in carbon steel boiler tubes. Slow strain rate tests (SSRT) were conducted under boiler water conditions to study the effect of temperature, oxygen level, and stress conditions on crack initation and propagation on SA-210 carbon steel samples machined out of boiler tubes. Heat treatments were also performed to develop various grain size and carbon content on carbon steel samples, and SSRTs were conducted on these samples to examine the effect of microstructure features on SAC cracking. Mechanisms of SAC crack initation and propagation were proposed and validated based on interrupted slow strain tests (ISSRT). Water chemistry guidelines are provided to prevent SAC and fracture mechanics model is developed to predict SAC failure on industrial boiler tubes.

  4. High Carbon Alloy Steels with Multiple Types of Ultra-fine Carbides and Their Characteristics

    MA Yong-qing; GAO Hong-tao; QI Yu-hong; ZHANG Zhan-ping; DAI Yu-mei; LIU Yan-xia

    2004-01-01

    Under normal forging and annealing conditions, there are different ultra fine carbides (M3C, M23C6, M7C3, M6C and MC) in high carbon alloy steels when alloy composition design is carried out properly. On the basis of carbides transformation orderliness, the alloy composition design of the high carbon alloy steels is conducted by phase-equilibrium thermodynamic calculation for Fe-Cr-W-Mo-V-C system. The nucleation and growth of new carbides, dissolution of previous partial carbides in these steels during annealing process, all these lead to ultra-fine distribution of carbides. Due to different crystal structures of carbides and different thermodynamics as well dynamics parameters of the carbides dissolution and precipitation, the range of quenching temperature of these steels is widened, and the good temper-resistance is obtained. The characteristics of heat treatment process and microstructure variance, and the carbides transformation for different temperature are explained by the phase-equilibrium component satisfactorily. Their bend and yield strength,flexibility and toughness all are advanced markedly comparing with that of kindred steels. Results of the applications have proved that the microstructure of ultra-fine carbides in these steels played importance roles in the enhancement of edginess and fatigue crack resistance of the die and knives.

  5. BORATING OF CARBON AND ALLOY STEEL IN BOILING LAYER

    N. Koukhareva

    2012-01-01

    Full Text Available The paper describes how to obtain boride coatings on steel 20, 4X5MФС, X12M being treated in a boiling layer of metallothermic powder environment. Phase and chemical compositions, hardness and wear- resistance of boride coatings

  6. Carbonated aqueous media for quench heat treatment of steels

    Nayak, U. Vignesh; Rao, K. M. Pranesh; Pai, M. Ashwin; Prabhu, K. Narayan

    2016-07-01

    Distilled water and polyalkylene glycol (PAG)-based aqueous quenchants of 5 and 10 vol.% with and without carbonation were prepared and used as heat transfer media during immersion quenching. Cooling curves were recorded during quenching of an inconel 600 cylindrical probe instrumented with multiple thermocouples. It was observed that the vapor stage duration was prolonged and the wetting front ascended uniformly for quenching with carbonated media. The cooling data were analyzed by determining the critical cooling parameters and by estimating the spatially dependent probe/quenchant interfacial heat flux transients. The study showed significantly reduced values of heat transfer rate for carbonated quenchants compared to quenchants without carbonation. Further, the reduction was more pronounced in the case of PAG-based carbonated quenchants than carbonated distilled water. The results also showed the dependence of heat transfer characteristics of the carbonated media on polymer concentration. The effect of quench uniformity on the microstructure of the material was assessed.

  7. Carbon content influence on the peritectic reaction path in stainless steels

    J. Głownia

    2013-01-01

    Full Text Available An important role for the peritectic reaction path in castings of stainless steel play small changes in a carbon content (e.g. from 0,02 to 0,06 % C, at maintaining constant chromium and nickel values. An influence of the carbon content on the peritectic reaction stages constitutes the subject of studies. The calculations of the steel solidification pathways in the four-component system, of a constant chromium and nickel content of 18 % and 9 % – respectively and of various carbon content from 0,01 to 0,06 %, were performed. It was proved by means of the PANDAT program that the carbon concentration increases the Cr segregation and thereby changes the solidification path under actual conditions.

  8. Adhesion of composite carbon/hydroxyapatite coatings on AISI 316L medical steel

    J. Gawroński

    2009-07-01

    Full Text Available In this paper are contains the results of studies concerning the problems associated with increased of hydroxyapatite (HAp adhesion, manufactured by using Pulse Laser Deposition (PLD method, to the austenitic steel (AISI 316L through the coating of carbon interlayer on it. Carbon coating was deposited by Radio Frequency Plasma Assisted Chemical Vapour Deposition (RF PACVD method.Test results unequivocally showed that the intermediate carbon layer in a determined manner increase the adhesion of hydroxyapatite to the metallic substrate. Obtained results give rise to deal with issues of manufacturing composite bilayer – carbon film/HAp – on ready implants, casted from austenitic cast steel by lost-wax process method as well as in gypsum forms.

  9. Microstructural characteristic of low carbon microalloyed steels produced by thermo-mechanical controlled process

    The microstructural characteristic of the low carbon microalloyed steels produced by thermo-mechanical controlled processing was investigated by means of optical and transmission electron microscopies. Polygonal ferrite and acicular ferrite were found in OM; under TEM, acicular ferrite with high dislocation density, ultra-fine grain ferrite, layer of thin martensite film and precipitate phase were identified in 560 MPa grade Ti-Nb and Ti-Nb-V microalloyed steels. An ultra-fine dispersion of precipitate phase was also found in Ti-Nb-V steel. These fine-scale microstructures exhibit excellent strength and fracture toughness, which is the main reason that TMCP is widely used in the production of high-strength low-alloy steels

  10. Influence of manganese and nickel on properties of low-carbon steels with 13% Cr

    Studied is the influence of manganese and nickel on mechanical properties and resistance-to-corrosion of the 13% content chromium steels containing 0.1-0.2%C. It is shown that manganese introduction results is the increase of strength characteristics of hardened steels because of delta-ferrite formation suppresion and solid solution strengthening. The delayed cooling during hardening permits to increase ductility and impact strength. Low-carbon 13% content chromium steels alloyed with nickel, molybdenum and aluminium have high heat resistance at temperatures up to 500 deg C due to the precipitation of intermetallics atlading. Chrome-manganese and chrome-nickel steels have a high resistance-to-corrosion in the hardened state in the neutral and weak-acid media

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

    M. Mazur

    2010-07-01

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

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

    Bogucki R.

    2014-10-01

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

  13. Precipitation strengthening and mechanical properties of ultra low carbon bainitic steel with Cu addition

    Effect of ageing parameters on tensile properties and impact energy of ultra low carbon bainitic steel (ULCB) was established. The investigated HN3MCu1.5 steel belongs to a new group of structural steels, which are going to be applied for constructions working at low temperatures.. The chemical composition of the steel is given. The microstructure of the steel after ageing at temperature 640oC during to 100 hours was observed by optical and electron microscopy. Special attention was paid to study primary austenite grain size, which determines the average diameter of bainite-martensite packet size and thus the impact transition temperature according to empirical equations. Then the quantitative determination of the average diameter of precipitates and the interparticle spacing was studied to calculate the precipitation strengthening effect on yield strength. The empirical equation, which relates effect of ageing time to the yield strength was determined. It was established that the optimum mechanical properties of HN3MCu1.5 steel aged at 649oC are achieved for ageing time in the range of 1 - 10 hours. For the above ageing parameters the investigated steels had: YS = 700-661 MPa, TS = 814-741 MPa and impact energy KCV = 150-170 J determined on Charpy V specimens at temperature -80oC. (author)

  14. New low carbon Q and P steels containing film-like intercritical ferrite

    In this work, the application of the Quenching and Partitioning (Q and P) process to two low-carbon steels has led to the development of a new kind of steel microstructure formed by laths of martensite separated by films of intercritical ferrite and retained austenite. The chemical compositions of the steels have been specially designed for this process, containing 3.5 wt.% Mn to retard the formation of bainite and combinations of Si and Al to avoid cementite precipitation. The microstructural changes occurring during the application of the heat treatments are discussed in terms of the current knowledge of the Q and P process and the experimental observations. A significant amount of retained austenite has been obtained in both steels after application of appropriate heat treatments, especially in the steel alloyed with higher amount of Si, in which the volume fraction of retained austenite reached values up to 0.19. Tensile tests in some selected specimens of both materials have shown outstanding combinations of strength and ductility, indicating that the designed Q and P steels are a promising candidate for the development of a new generation of advanced high strength steels.

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

    X.T.Liu; J.Z.Cui

    2004-01-01

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

  16. Factors affecting the strength and toughness of ultra-low carbon steel weld metal

    Van Slyke, Jonathon J.

    1999-01-01

    The factors that affect strength and toughness often ultra-low carbon steel weld samples (HSLA-80 and HSLA-100), welded using the gas metal arc welding (GMAW) process and new ultra-low carbon consumable electrodes, were studied. The analysis was confined only to the weld metal, and the base metal was not considered. Analysis methods included optical microscopy, scanning electron microscopy, and transmission electron microscopy. Energy dispersive x- ray analysis was performed in the transmissi...

  17. In Situ Observation of Phase Transformation in Low-Carbon, Boron-Treated Steels

    Zhang, Di; Shintaku, Yoshiaki; Suzuki, Shuichi; Komizo, Yu-Ichi

    2012-02-01

    It is known that adding the appropriate amount of boron to steels dramatically increases their hardness and toughness as a result of the transition of the microstructure from grain boundary nucleation to intragranular nucleation. In this study, precipitation and phase transformation kinetics in heat-affected zones of low-carbon, boron-treated steels are observed directly by high-temperature laser scanning confocal microscopy. The effects of boron content and austenite grain size on the phase transformation process are investigated systematically by quantifying the transformation product, the transformation start temperature, the average length of the ferrite plates, and the average number of potent nucleation sites. Finally, detailed methods for controlling and optimizing the microstructure in the heat-affected zones of low-carbon, boron-treated steels are discussed.

  18. Kinetics and structural studies of the atmospheric corrosion of carbon steels in Panama

    The corrosion of a carbon steel was studied in different atmospheres at sites in the Republic of Panama. The weight loss (corrosion penetration) suffered by the carbon steel is related to time by a bilogarithmic law. Moessbauer spectroscopy indicated the rust was composed of non-stoichiometric magnetite (Fe3-xO4), maghemite (γ-Fe2O3), goethite (α-FeOOH) of intermediate particle size, lepidocrocite (γ-FeOOH) and superparamagnetic particles. Magnetite formation is related to the alternating dry-wet cycles. Goethite is related to corrosion penetration by a saturation type of behavior, following a Langmuir type of relationship. Goethite in rust protects steel against further atmospheric corrosion

  19. Slow strain rate testing of carbon steel in solutions with high nitrate concentrations

    Processing of high-level nuclear waste for permanent disposal will cause changes to the present inhibited compositions at the Savannah River Site. Temperature and nitrate concentration may reach new high levels during salt dissolution in the carbon steel waste tanks with certain removal methods. Proper inhibitor concentrations are necessary to minimize the potential for nitrate-induced stress corrosion cracking to maintain the integrity of the waste tanks. Slow strain rate testing and potentiodynamic polarization were used to investigate whether stress corrosion cracking would initiate under bounding removal conditions. Test conditions for two carbon steels included nitrate concentrations of 5.5 and 9.7 M at a maximum temperature of 95 degrees C. The steels were found to be resistant to SCC in the more aggressive waste compositions at the present inhibitor concentrations of 0.6 M sodium hydroxide and 0.5 M sodium nitrite

  20. 75 FR 26273 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From China

    2010-05-11

    ... COMMISSION Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From China AGENCY... pipe (``seamless SLP pipe''), provided for in subheadings 7301.19.10, 7304.19.50, 7304.31.60, 7304.39... China of seamless SLP pipe, and that such products are being sold in the United States at less than...

  1. 78 FR 70069 - Circular Welded Carbon-Quality Steel Pipe From China

    2013-11-22

    ... in these reviews. Background The Commission instituted these reviews on June 3, 2013 (78 FR 33108) and determined on September 6, 2013 that it would conduct expedited reviews (78 FR 59371, September 26... COMMISSION Circular Welded Carbon-Quality Steel Pipe From China Determination On the basis of the record...

  2. Study of thermal hardening effect on fracture toughness of medium carbon steels

    Microstructural studies and mechanical tests of medium carbon steels (0.49-0.63% C) have shown that heat treatment of hot rolled specimens results in considerable variations in fracture toughness depending on cooling rate in the range of 0.5-10 deg C/s. It has been found that high values of fracture toughness are conditioned by actual grain refinement

  3. The study of retained austenite morphology in low-carbon silico manganese steels

    The experimental results of a retained austenite morphology in low-carbon steels of a chemical composition of 0.2% C, 1.5% Mn, and 1.5% Si are presented. The microstructure of retained austenite after martensitic transformation in samples quenched from austenite region, dual phase region and suggested isothermal bainitic transformation were analysed. (author)

  4. Assessment of wall-thinning in carbon steel pipe by using laser-generated guided wave

    Kim, Do Yong; Cho, Youn Ho; Lee, Joon Hyun [Pusan National University, School of Mechanical Engineering, Busan (Korea, Republic of)

    2010-10-15

    The objective of this research is to estimate the crack location and size of a carbon steel pipe by using a laser ultrasound guided wave for the wall thinning evaluation of an elbow. The wall thinning of the carbon steel pipe is one of the most serious problems in nuclear power plants, especially the wall thinning of the carbon steel elbow caused by Flow-Accelerated Corrosion (FAC). Therefore, a non-destructive inspection method of elbow is essential for the nuclear power plants to operate safely. The specimens used in this study were carbon steel elbows, which represented the main elements of real nuclear power plants. The shape of the wall thinning was an oval with a width of 120mm, a length of 80mm, and a depth of 5mm. The L(0,1) and L(0,2) modes variation of the ultrasound guided wave signal is obtained from the response of the laser generation/air-coupled detection ultrasonic hybrid system represent the characteristics of the defect. The trends of these characteristics and signal processing were use dto estimate the size and location of wall thinning

  5. 77 FR 19192 - Circular Welded Carbon-Quality Steel Pipe From India: Preliminary Affirmative Countervailing Duty...

    2012-03-30

    ... Welded Carbon Quality Steel Pipe from the People's Republic of China, 73 FR 31970 (June 5, 2008) and.... Provision of Captive Mining Rights for Coal and Iron Ore; the Provision of High-Grade Ore for LTAR. Programs... Republic of Vietnam: Initiation of Countervailing Duty Investigations, 76 FR 72173 (November 22,...

  6. Corrosion Protection of Carbon Steel Using Poly aniline Composite with Inorganic Pigments

    Two inorganic pigments (TiO2 and SiO2) were used to prepare composites with poly aniline (PANI) by situ polymerization method. PANI and PANI composites with SiO2 and TiO2 were characterized using Fourier transform infrared spectroscopy and X-ray diffraction. The morphology of the synthesized pigments (PANI , PANI-SiO2 and PANI-TiO2) was examined using scanning electron microscopy. Samples were then used as pigments through blending them with acrylic paint and applied on the surface of carbon steel panels. Corrosion was evaluated for coating of carbon steel panels through full immersion test up to standard ASTMG 31. Mass loss was calculated after they have been exposed in acidic media. A digital camera was also used for monitoring corrosion visually on the surface of carbon steel specimens. The results revealed that acrylic paint pigmented by PANI-SiO2 composite was more efficient in corrosion protection for carbon steel compared with the other synthesized pigments. (author)

  7. Influence of plasma nitriding on the hardness of AISI 304 and low carbon steel

    Nitriding with plasma/ion nitriding technique for surface treatment of AISI 304 and low carbon steel as a machine component material has been done. Surface treatment is meant to improve the surface quality of metal especially its hardness. To reach the optimum condition it has been done a variation of nitriding pressure, while to analyse the result it has been done the hardness and microstructure test, and the nitrogen content. Result of the test indicates that: the optimum hardness obtained at 1.8 mbar of pressure that is 624.9 VHN or 2.98 times while the initial hardness is 210.3 VHN for AISI 304 and 581.6 VHN or 3.07 times compare with initial hardness 142.9 VHN for low carbon steel. The thickness of nitride layer for AISI 304 and low carbon steel is around 30 µm. Nitrogen contents after nitriding are 10.74% mass or 30.32% atom for AISI 304 and 6.81% mass or 21.76% atom for low carbon steel. (author)

  8. Regularities of Macroscopic Localization of Plastic Deformation in the Stretching of a Low-Carbon Steel

    Barannikova, S. A.; Kosinov, D. A.; Nadezhkin, M. V.; Lunev, A. G.; Gorbatenko, V. V.; Zuev, L. B.; Gromov, V. E.

    2014-07-01

    The special features of plastic deformation localization in the stretching of polycrystals of low-carbon steel 08 ss after hot rolling and electrolytic saturation with hydrogen are investigated. The main types and parameters of plastic flow localization in different stages of strain hardening are determined by the method of double-exposure speckle photography.

  9. Effects of temperature change on fatigue life of carbon steel in high temperature water

    Strain controlled fatigue tests of a carbon steel in oxygenated high temperature water were carried out under the condition of combined and synchronized mechanical and thermal strain cycling. The effects of temperature change on environmental fatigue life were investigated, showing basic conceptual data to evaluate the fatigue damage under the condition of transient temperature change of actual plant components

  10. 77 FR 20782 - Circular Welded Carbon Steel Pipes and Tubes From Thailand: Preliminary Results of Antidumping...

    2012-04-06

    ... investigation. See Antidumping Duty Order: Circular Welded Carbon Steel Pipes and Tubes From Thailand, 51 FR... Pipes and Tubes from Thailand, 51 FR 8341 (March 11, 1986). On March 1, 2011, the Department published a... Duty Order, Finding, or Suspended Investigation; Opportunity to Request Administrative Review, 76...

  11. 78 FR 21105 - Circular Welded Carbon Steel Pipes and Tubes From Thailand: Preliminary Results of Antidumping...

    2013-04-09

    ..., available in Antidumping Duty Order: Circular Welded Carbon Steel Pipes and Tubes from Thailand, 51 FR 8341... Duty Administrative Review, 75 FR 26922, 26923 (May 13, 2010), unchanged in Magnesium Metal From the Russian Federation: Final Results of Antidumping Duty Administrative Review, 75 FR 56989 (September...

  12. 75 FR 33578 - Certain Welded Carbon Steel Standard Pipes and Tubes from India: Preliminary Results of...

    2010-06-14

    ... FR 20278 (May 1, 2009). On June 24, 2009, in response to a request from the Wheatland Tube Company... Antidumping Duty Order; Certain Welded Carbon Steel Standard Pipes and Tubes from India, 51 FR 17384 (May 12... Tubes from India, 51 FR 17384 (May 12, 1986). On May 1, 2009, the Department published in the...

  13. Certain properties of thin-film niobium carbide coatings on carbon steels obtained in molten salts

    Niobium carbide coatings have been deposited by means of a currentless transfer of electronegative niobium metal to a more electropositive substratum made of carbon steel in molten salts containing niobium compounds. Corrosion resistance of niobium carbide coated products is studied, wear resistance and tribological characteristics of the coatings are determined

  14. 78 FR 2658 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Rescission of Antidumping Duty...

    2013-01-14

    ...; Opportunity To Request Administrative Review, 77 FR 59894 (October 1, 2012). \\2\\ See Letter from Nucor... Countervailing Duty Administrative Reviews and Request for Revocation in Part, 77 FR 71575 (December 3, 2012). \\4... International Trade Administration Carbon and Certain Alloy Steel Wire Rod From Mexico: Rescission...

  15. Application of phosphating techniques to aluminium and carbon steel surfaces using nitro guanidine as oxidizing agent

    Phosphate coatings are inorganic crystalline deposits laid down uniformly on properly prepared surfaces by a chemical reaction with the treated base metal. The reaction consists in dissolving some surface metal by acid attack and then causing surface neutralization of the phosphate solution with consequent precipitation of the phosphate coating. Phosphate coatings do not provide appreciable corrosion protection in themselves. They are useful mainly as a base for paints, ensuring good adherence of paint to steel and decreasing the tendency for corrosion to under cut the paint film at scratches or other defects. In this work firstly were realized phosphate on standard carbon steel, employing technical of cold phosphate (at 40 Centigrade degrees and with a treatment time of 30 minutes) and hot phosphate (at 88 Centigrade degrees and with a treatment time of 15 minutes), where with this last were obtained the best results. Both methods used phosphate solutions of Zn/Mn and using as catalyst Nitro guanidine. Aluminium surfaces were phosphate used solutions of Cr and as catalyst Sodium bi fluoride. The phosphating on this surface were realized at temperature of 50 Centigrade degrees and with a treatment time of 10 minutes. In this work were obtained a new phosphate coatings on steel surfaces, these coatings were realized with a phosphate solution manufactured with the precipitates gathered during the hot phosphating on carbon steel. These coatings show excellent physical characteristics and of corrosion resistance. Were determined the physical testings of the coatings phosphate obtained on carbon steel and aluminium surfaces. These testing were: roughness, thickness, microhardness and adhesion. The best results were showed in carbon steel phosphate with precipitated solutions. The technical of analysis for activation with thermic neutrons was used to determine the phosphate coatings composition. Finally, corrosion testings were realized by means of two methods

  16. Analysis of low-carbon industrial symbiosis technology for carbon mitigation in a Chinese iron/steel industrial park: A case study with carbon flow analysis

    CO2 mitigation strategies in industrial parks are a significant component of the Chinese climate change mitigation policy, and industrial symbiosis can provide specific CO2 mitigation opportunity. Technology is important to support symbiosis, but few studies in China have focused on this topic at the industrial park level. This research presented a case study in a national iron and steel industrial park in China. Focus was given onto carbon mitigation through industrial symbiosis technology using substance flow analysis (SFA). Three typical iron and steel industry technologies, including coke dry quenching (CDQ), combined cycle power plant (CCPP), and CO2 capture by slag carbonization (CCSC) were evaluated with SFA. Technology assessment was further conducted in terms of carbon mitigation potential and unit reduction cost. Compared with the Business as usual (BAU) scenario, application with CDQ, CCPP, and CCSC reduced the net carbon emissions by 56.18, 134.43, and 222.89 kg CO2 per ton crude steel inside the industrial parks, respectively, including both direct and indirect emissions. Economic assessment revealed that the unit costs for the three technologies were also high, thereby necessitating national financial support. Finally, relevant policy suggestions and future concerns were proposed and discussed. - Highlights: • A typical carbon mitigation case study on China iron/steel industrial park. • Using carbon SFA to investigate mitigation effects of industrial symbiosis technology. • CCPP greatly reduced the indirect carbon emission embodied in power purchase. • CCSC reduced the carbon emission by distributing fixed carbon into by-product. • Specific low carbon-tech promotion policies fit to China was discussed and proposed

  17. Corrosion of carbon steel in sodium methanoate solutions

    The behaviour of steel electrodes in sodium methanoate solutions was studied by coupling electrochemical techniques (voltammetry, OCP vs. time) with in situ micro-Raman spectroscopy analyses of the corrosion products. The polarisation curves depended strongly on the methanoate concentration. For the smallest concentration (10-3 mol L-1), the current density increased regularly with the applied potential. So the behaviour of the electrode was typical of an active material. In contrast, for the largest concentration (10-1 mol L-1), the curves obtained were typical of a passive material. Methanoate ions favoured growth and stability of a passive oxide film more likely by adsorbing on its surface. The polarisation curve obtained for the intermediate concentration (10-2 mol L-1) was unusual and testified of an imperfect passivation of the steel surface. Finally, steel electrodes were left at the open circuit potential in the methanoate solutions. In any case, the passivity was rapidly lost and a general corrosion of the surface took place. In situ Raman spectroscopy analyses at the early stage of the corrosion process demonstrated that the first product to form was a green rust, GR(HCOO-). It was oxidised later into γ-FeOOH (lepidocrocite) by dissolved O2. The process is then typical of what is usually observed in neutral or alkaline media, whatever the anions present and responsible of the GR formation. A new and detailed characterisation of GR(HCOO-) by X-ray diffraction was performed and a crystal structure is proposed.

  18. Compatibility studies on carbon steel and Monel-400 in steam generator cleaning formulations

    EDTA based Steam Generator (SG) cleaning formulations are being used worldwide to remove the sludge accumulated on tubes, tube sheets and the baffle plates of the tubes in steam generators. In early Indian PHWRs, SG shells are made up of carbon steel and the tubes are made of Monel-400. Corrosion compatibility of carbon steel and Monel-400 in SG cleaning formulations were evaluated so as to assess the suitability of these formulations for cleaning the steam generators. SG cleaning iron formulation contains 10% EDTA at pH 6 (pH additive NH3) along with 1% hydrazine. These experiments were carried out at 95 degC under inert condition. The SG cleaning copper formulation consists of 5% EDTA at pH 9.5 (pH adjusted by EDA) and 2% hydrogen peroxide. These experiments were conducted at room temperature. Further, experiments were carried out to study the effect of oxygen, the effect of pH additives namely NH3, EDA and NaOH, effect of presence of Fe3+ ions, effect of roughening of the surface on corrosion rate of carbon steel. The role of hydrazine and effect of decomposed products of EDTA on corrosion of carbon steel were also studied. Elaborate study was done on specimens that were prepared by cold-rolling and hot-rolling. Inhibitors like Rodine-92B and some non-sulphur inhibitors such as 1,2,3 benzotriazole, hexynols etc. were tested to determine their inhibition efficiency on corrosion of carbon steel. Microscopic observations on the exposed specimens were done to observe any localised attack. (author)

  19. Influence of plastic deformation on CCT-diagrams of low-carbon and medium-carbon TRIP-steels

    M. Opiela

    2008-07-01

    Full Text Available Purpose: The aim of the paper is to investigate the influence of plastic deformation and cooling conditions on a structure and a shape of CCT-diagrams of new-developed TRIP-aided microalloyed steels.Design/methodology/approach: The diagrams of undeformed and plastically-deformed supercooled austenite transformations for low-carbon and medium-carbon microalloyed steels were determined. A part of the specimens were austenitized at a temperature of 1100°C, then slowly cooled to 900°C and next cooled to ambient temperature with a various rate from 1 to 300°C/s. To investigate the influence of plastic deformation on a shape of CCT (Continuous Cooling Transformations diagrams, another part of the specimens were 50% deformed at 900°C and cooled to ambient temperature with a rate from 88 to 1°C/s. The DIL805A/D dilatometer, with a LVDT-type measuring head, was used to carry out dilatometric tests.Findings: It was found that a shape of CCT diagrams of elaborated steels predisposes them for multiphase sheets manufacturing. The new-developed steels possess ferritic and bainitic bays put forward to short times and pearlitic regions put aside. However, cooling the steel with a constant rate from austenitizing temperature doesn’t lead to obtaining proper participation of ferrite. Plastic deformation of steel has a profitable influence on the shape of supercooled austenite curves. The region of γ→α transformation is translated to the left at simultaneous raise of start temperature of austenite into ferrite transformation resulting in definitely higher ferrite fraction. Moreover, significant refinement of microstructure in a whole range of cooling rate was also obtained.Research limitations/implications: To increase the ferrite fraction, modification of the cooling after hot-working finishing should be applied. In the fist stage, steel should be rapidly cooled in order to enter the range of γ→α transformation and successively slowly cooled in a

  20. Effect of microstructure of carbon steel on magnetite formation in simulated Hot Conditioning environment of nuclear reactors

    Sinha, Prafful Kumar, E-mail: prafful@barc.gov.in; Kiran Kumar, M.; Kain, Vivekanand

    2015-09-15

    Highlights: • Heat treatments used to tailor microstructure of a low and a high carbon steel. • Oxide growth rates established in Hot Conditioning simulated environment. • Only magnetite formed on all microstructural conditions of both the steels. • Growth rate was higher for all microstructures of high carbon steel upto 72 h. • After 72 h growth rate stabilized in narrow band for all microstructures of a steel. - Abstract: The objective of present investigation is to establish the role of starting microstructure of carbon steel on the magnetite formation behaviour in Hot Conditioning simulated environment. Two grades of carbon steel (low and high carbon) were subjected to selective heat-treatments to generate different microstructures: martensite, tempered martensite and modified ferrite–pearlite. Oxidation was carried out in lithiated water of pH 10–10.2 in a static autoclave at 270 °C. The results of the investigation clearly establish that: (a) high carbon steel (0.63% C) showed a relatively higher rate of oxidation over the low carbon (0.08% C) grade at all the test durations and (b) the oxidation rates for both the grades were sensitive to microstructural differences at initial stages of oxidation while the differences narrowed down after 72 h of exposure. The oxide formed was established to be magnetite on all the specimens.

  1. Effect of microstructure of carbon steel on magnetite formation in simulated Hot Conditioning environment of nuclear reactors

    Highlights: • Heat treatments used to tailor microstructure of a low and a high carbon steel. • Oxide growth rates established in Hot Conditioning simulated environment. • Only magnetite formed on all microstructural conditions of both the steels. • Growth rate was higher for all microstructures of high carbon steel upto 72 h. • After 72 h growth rate stabilized in narrow band for all microstructures of a steel. - Abstract: The objective of present investigation is to establish the role of starting microstructure of carbon steel on the magnetite formation behaviour in Hot Conditioning simulated environment. Two grades of carbon steel (low and high carbon) were subjected to selective heat-treatments to generate different microstructures: martensite, tempered martensite and modified ferrite–pearlite. Oxidation was carried out in lithiated water of pH 10–10.2 in a static autoclave at 270 °C. The results of the investigation clearly establish that: (a) high carbon steel (0.63% C) showed a relatively higher rate of oxidation over the low carbon (0.08% C) grade at all the test durations and (b) the oxidation rates for both the grades were sensitive to microstructural differences at initial stages of oxidation while the differences narrowed down after 72 h of exposure. The oxide formed was established to be magnetite on all the specimens

  2. Chloride induced localized corrosion in simulated concrete pore solution: effect of a phosphate-based inhibitor on the behavior of 304L stainless steel compared to carbon steel

    In this paper, the acoustic emission technique coupled with electrochemical measurements was used to determine, in simulated concrete pore solution (Ca(OH)2), the critical value [Cl-] / [OH-], which prevents the pitting corrosion initiation of AISI 304L austenitic stainless steel, and to compare this critical value with that of the carbon steel in the same medium with and without inhibitor Na3PO4. The results show that for the austenitic stainless steel, the critical threshold of pitting corrosion initiation is around 5, while for carbon steel without inhibitor in Ca(OH)2 solution, it has a low value of about 0.6. However, the presence of the inhibitor Na3PO4 in this solution leads to the formation of a protective phosphate layer on the steel surface, increasing the critical ratio [Cl-] / [OH-] from 0.6 to 15. Under these conditions, the corrosion behavior of carbon steel is improved and, thanks to the blocking of pitting sites by the Na3PO4 inhibitor, it becomes much more resistant to localized corrosion than AISI 304L austenitic steel. (authors)

  3. Work-Hardening and Deformation Mechanism of Cold Rolled Low Carbon Steel

    Wang Su-Fen

    2013-01-01

    Full Text Available The study reports the mechanical property and microstructure of cold rolled low carbon steel and its work-hardening behavior in the deformation process. The tensile test in room temperature of low carbon steel was implemented for the different cold rolling deformation, the stress-strain curve was draught according to the relationship between strength and deformation and fitted for the polynomial fitting, the strain hardening exponent (n of test steel was calculated by the Hollomon method. In the whole cold deformation process, the work-hardening of cold rolled steel is significant, work-hardening rate has different degrees decreasewith the deformation increase. The strain hardening exponent is simple and dislocation strengthening is the major cause of hardening processing. The microstructure of test steel was observed after different deformation, the room temperature organization is the ferrite and few pearlite. The original grain is equiaxial and the average grain size is about 23.5 um, and pearlite distributes in ferrite grain boundaries. It was consequently established the cold deformation energy according to dislocation model, the cold deformation energy is main concerned on the plastic deformation to resistance and the initial stress.

  4. Development of high strength hot rolled low carbon copper-bearing steel containing nanometer sized carbides

    A low carbon ferritic steel was alloyed with Ti, Mo and Cu with the intention of achieving greater increment in strength by multiple precipitate strengthening. The steel is hot rolled and subjected to interrupted cooling to enable precipitation of Ti–Mo carbides and copper. Thermodynamic calculations were carried out to determine equilibrium phase fractions at different temperatures. Microstructure characterization using transmission electron microscopy and composition analysis revealed that the steel contains ~5 nm size precipitates of (Ti,Mo)C. Precipitation kinetics calculations using MatCalc software showed that mainly body centered cubic copper precipitates of size < 5nm form under the cooling conditions in the present study. The steel has the high tensile strength of 853 MPa and good ductility. The yield strength increases by 420 MPa, which is more than that achieved in hot rolled low carbon ferritic steels with only copper precipitates or only carbide precipitates. The precipitation and strengthening contribution of copper and (Ti,Mo)C precipitates and their effect on the work hardening behavior is discussed

  5. Stress-corrosion crack initiation behavior of carbon steel in simulated BWR environment

    Carbon steels and low-alloy steels are said to possess, even though susceptible to stress-corrosion cracking themselves, conspicuously longer life than weld-sensitized Type 304 stainless steels in actual boiling water reactor (BWR) primary coolant environments of high-temperature, high-purity water containing some dissolved oxygen. This has been examined for a carbon steel pipe material and its weld by conducting uniaxial constant-load tests as a laboratory accelerated test. By statistically analyzing the distribution of stress-corrosion cracking lifetimes and metallographical examining the features of stress-corrosion crack initiation in an SEM, following results have been obtained: (1) the stress-corrosion cracking lifetime obeys the exponential distribution model; (2) stress-corrosion cracks are initiated at the bottom of corrosion pits, and it appears possible to analyze their initiation conditions in terms of stress-intensity calculated regarding the pit as a sharp crack; (3) the microcracks as initiated at the corrosion pit are non-propagative per se, so that it is only when they have grown into a main crack by coalescence with nearby microcracks that steady propagation becomes possible; and (4) both the process of pit initiation and that of microcrack coalescence can be described as a Poisson stochastic process just as for the stainless steels in the same environment, so that the whole process of stress-corrosion crack initiation can be conceived as consisting of these two independent Poisson stochastic processes connected in serial succession

  6. The effect of chloride ion on the iron elution from carbon steel in high temperature water

    In Hamaoka-5 nuclear power plant, the sea water entered into the reactor during the shutdown on May in 2011. The structural materials were exposed to the high temperature water containing chloride ion (Cl-). Carbon steel is less corrosion-resistant than stainless steel and the corrosion might be accelerated. Oxide growth of carbon steel may cause the change of Co-60 deposition behavior during the operation. Then the perceiving the state of oxide film on the surface of carbon steel is important. We conducted the corrosion tests for 24hrs with carbon steel under high temperature water containing Cl- to estimate the state of the surface and iron elution of the actual plant. In the cases of the prefilmed specimens, without Cl-, the amount of iron elution was small at 513 K. On the other hand, under the water condition containing Cl- iron elution from carbon steel occurred. The iron elution rate under the water condition of 423 K was slightly faster than 513 K. The average values of iron elution rate under the condition of 400ppm as Cl- were approximately 0.03 mg/cm2/h. The dependency of Cl- concentration on iron elution rate did not appear at the both of 423 and 513 K. In the case of the specimens without oxide film, the iron elution rate under the water condition of 423 K was much faster than 513 K under the water conditions with and without Cl-. The iron elution rate of the specimens without oxide film was affected by the concentration of Cl- with the exception of the test at 423 K. At the higher Cl- concentration, iron elution was accelerated. Furthermore, we conducted the corrosion tests at 323 K for 500 hours which simulated the water condition after the shutdown of the reactor. It was also confirmed that iron apparently eluted from the specimen in these tests. This result indicated that iron elution possibly occurred in the actual plant. The analyses of the oxide film on the surface of specimens after the several tests were conducted. We also discussed the

  7. Effects of Carbon on the CG HAZ Toughness and Transformation of X80 Pipeline Steel

    Xiaohuai XUE; Luhai WU; Bainian QIAN; Jingli LI; Songnian LOU

    2003-01-01

    X80 pipeline steel produced by TMCP has high strength and high toughness with ultrafine grain microstructure. The microstructure coarsens and the toughness worsens at the coarse grained (CG) HAZ apparently after weld simulation. The experimental results indicated that the bainitic ferrite and the second phases formed at cooling are differently as the variation of carbon in base metal. In low carbon steels, the bainitic ferrite laths are long and narrow, the second phases are complex including residual austenite, martensite, the M-A constituent and the Fe3C carbide. The formation of Fe3C carbide is the main reason of the poor toughness in CG HAZ. The ultralow carbon in base metal, however, can improve the CG HAZ toughness through restraining the formation of carbides, decreasing the M-A constituent, increasing the residual austenite content, which are beneficial to the CG HAZ toughness.

  8. Finite Element Analysis of Fire Truck Chassis for Steel and Carbon Fiber Materials

    Salvi Gauri Sanjay

    2014-07-01

    Full Text Available Chassis is the foremost component of an automobile that acts as the frame to support the vehicle body. Hence the frame ought to be very rigid and robust enough to resist shocks vibrations and stresses acting on a moving vehicle. Steel in its numerous forms is commonly used material for producing chassis and overtime alumimium has acquired its use. However, in this study traditional materials are replaced with ultra light weight carbon fiber materials. High strength and low weight of carbon fibers makes it ideal for manufacturing automotive chassis. This paper depicts the modal and static structural analysis of TATA 407 fire truck chassis frame for steel as well as carbon fibers. From the analyzed results, stress, strain and total deformation values were compared for both the materials. Since it is easy to analyze structural systems by finite element method, the chassis is modified using PRO-E and the Finite Element Analysis is performed on ANSYS workbench.

  9. Carbon transfer between 2 1/4 Cr 1 Mo alloy and austenitic steels (experiments in anisothermal loops)

    Studies on carbon transfer between the ferritic steel 2 1/4 Cr 1 Mo and the austenitic steels 316L and 321H have shown that there is not any measurable carbon transfer in the operating conditions of the secondary circuit of PHENIX (475 deg C was the maximal temperature of the 2 1/4 Cr 1 Mo steel). A significant carbon transfer has been observed between the ferritic steel and the 316L steel when the 321H was replaced by the 2 1/4 Cr 1 Mo steel in the same thermohydraulic conditions (the ferritic steel was then used up to 545 deg C). This experiment has demonstrated the importance of the temperature and the initial carbon content of the ferritic steel as parameters in the decarburization process. It appears that decarburization may not be sensitive to the thermohydraulic conditions at least in the range investigated in those experiments. In the other hand the 316L steel is observed to have been carburized, the degree of carburization remaining appreciably constant and independent on the temperature between 400 deg C and 550 deg C

  10. The effect of temperature on carbon steel corrosion under geological conditions

    Graphical abstract: The carbon steel corrosion under simulated geological conditions has been investigated and the results show the formation of iron sulphide on steel surface due to microbial corrosion at 30 °C and to the reduction by hydrogen of pyrite originating from claystone into iron monosulphide and hydrogen sulphide at 90 °C. - Highlights: • The role of temperature and microbial activity on steel corrosion was investigated. • At 30 °C, steel developed iron sulphide surface due to microbial activity. • At 90 °C, the microbial activity was inhibited. • At 90 °C, H2S was produced via pyrite reduction by H2. • Sulphide production may occur at high temperature. - Abstract: We investigated the role of temperature on the carbon steel corrosion under simulated geological conditions. To simulate the effect of temperature increase due to radioactive decay, we conducted batch experiments using Callovo-Oxfordian (COx) claystone and synthetic water formation with steel coupons at 30 °C and 90 °C for 6 months. The corrosion products have been studied by scanning electron microscope/energy dispersive X-ray spectroscopy, X-ray diffraction and micro-Raman spectroscopy. At 30 °C, experiments showed the formation of magnetite and iron sulphide, indicating the activation of sulphate-reducing bacteria. At 90 °C a continuous iron sulphide layer was identified on steel surface due to the reduction by hydrogen of pyrite originating from claystone into pyrrhotite and hydrogen sulphide. Thus, sulphide production may occur even in the absence of microbial activity at high temperature and must be taken into consideration regarding the near-field geochemical evolution

  11. Effect of rare earths on impact toughness of a low-carbon steel

    Highlights: → RE as alloying element in steels instead of used to deoxidize and desulfurize. → An appropriate RE content can improve significantly the impact toughness of the low carbon steel. → Excessive RE content induces a volume of martensite precipitates at grain boundaries. → The bainite transformation is benefit from RE additions. → The ferrite reconstructive transformation might be changed by RE enrichment at grain boundaries. -- Abstract: Studies of an industrial low-carbon steel (B450NbRE) suggest that the impact toughness is unexpectedly low under its practical service, probably resulting from the unstable recovery of rare earths (RE) in steelmaking. The purpose of this work is to investigate the effect of RE on the impact toughness in low-carbon steel. The B450NbRE steels with content of 0.0012-0.0180 wt.% RE were produced by vacuum induction furnace. The impact toughness and microstructure were investigated after hot rolled. The Gleeble-1500 thermal simulator was used to validate the effect of RE on the microstructure. The results indicate that the microstructure of hot-rolled steels is characterized by polygonal ferrite, quasi-polygonal ferrite, bainite and pearlite. The impact toughness increases with RE contents reaching the peak with content of 0.0047 wt.% RE, such a change exhibits the same rule as the case of the ferrite amount. However, this improvement in impact toughness is not only due to an increase in ferrite amount, but also the fine grained structure and the cleaner grain boundaries. And content of 0.0180 wt.% RE is excessive. Such an addition of the RE resulted in the martensite precipitates at the grain boundaries, which are extremely detrimental to impact toughness.

  12. Corrosion of carbon steel in sodium methanoate solutions

    Barchiche, C.; Sabot, R.; Jeannin, M. [Laboratoire d' etude des materiaux en milieux agressifs (LEMMA), EA 3167, Univ. La Rochelle, Bat. Marie Curie, Avenue Michel Crepeau, F-17042 La Rochelle cedex 01 (France); Refait, Ph., E-mail: prefait@univ-lr.f [Laboratoire d' etude des materiaux en milieux agressifs (LEMMA), EA 3167, Univ. La Rochelle, Bat. Marie Curie, Avenue Michel Crepeau, F-17042 La Rochelle cedex 01 (France)

    2010-02-15

    The behaviour of steel electrodes in sodium methanoate solutions was studied by coupling electrochemical techniques (voltammetry, OCP vs. time) with in situ micro-Raman spectroscopy analyses of the corrosion products. The polarisation curves depended strongly on the methanoate concentration. For the smallest concentration (10{sup -3} mol L{sup -1}), the current density increased regularly with the applied potential. So the behaviour of the electrode was typical of an active material. In contrast, for the largest concentration (10{sup -1} mol L{sup -1}), the curves obtained were typical of a passive material. Methanoate ions favoured growth and stability of a passive oxide film more likely by adsorbing on its surface. The polarisation curve obtained for the intermediate concentration (10{sup -2} mol L{sup -1}) was unusual and testified of an imperfect passivation of the steel surface. Finally, steel electrodes were left at the open circuit potential in the methanoate solutions. In any case, the passivity was rapidly lost and a general corrosion of the surface took place. In situ Raman spectroscopy analyses at the early stage of the corrosion process demonstrated that the first product to form was a green rust, GR(HCOO{sup -}). It was oxidised later into gamma-FeOOH (lepidocrocite) by dissolved O{sub 2}. The process is then typical of what is usually observed in neutral or alkaline media, whatever the anions present and responsible of the GR formation. A new and detailed characterisation of GR(HCOO{sup -}) by X-ray diffraction was performed and a crystal structure is proposed.

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

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

    2015-01-01

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

  14. The anaerobic corrosion of carbon steel in alkaline media – Phase 2 results

    Fennell P.A.H.

    2013-07-01

    Full Text Available In the Belgian Supercontainer concept a carbon steel overpack will surround high-level waste and spent fuel containers and be encased in a cementitious buffer material. A programme of research was carried out to investigate and measure the rate of anaerobic corrosion of carbon steel in an artificial alkaline porewater that simulates the aqueous phase in the cementitious buffer material. The corrosion rates were measured by monitoring hydrogen evolution using a manometric gas cell technique and by applying electrochemical methods. Phase 2 of the programme has repeated and extended previous Phase 1 measurements of the effects of radiation, temperature and chloride concentration of the anaerobic corrosion rate. This paper provides an update on the results from Phase 2 of the programme. The results confirm previous conclusions that the long-term corrosion rate of carbon steel in alkaline simulated porewater is determined by the formation of a thin barrier layer and a thicker outer layer composed of magnetite. Anaerobic corrosion of steel in cement requires an external supply of water.

  15. The effect of cyclic and dynamic loads on carbon steel pipe

    This report presents the results of four 152-mm (6-inch) diameter, unpressurized, circumferential through-wall-cracked, dynamic pipe experiments fabricated from STS410 carbon steel pipe manufactured in Japan. For three of these experiments, the through-wall crack was in the base metal. The displacement histories applied to these experiments were a quasi-static monotonic, dynamic monotonic, and dynamic, cyclic (R = -1) history. The through-wall crack for the third experiment was in a tungsten-inert-gas weld, fabricated in Japan, joining two lengths of STS410 pipe. The displacement history for this experiment was the same history applied to the dynamic, cyclic base metal experiment. The test temperature for each experiment was 300 C (572 F). The objective of these experiments was to compare a Japanese carbon steel pipe material with US pipe material, to ascertain whether this Japanese steel was as sensitive to dynamic and cyclic effects as US carbon steel pipe. In support of these pipe experiments, quasi-static and dynamic, tensile and fracture toughness tests were conducted. An analysis effort was performed that involved comparing experimental crack initiation and maximum moments with predictions based on available fracture prediction models, and calculating J-R curves for the pipe experiments using the η-factor method

  16. Nanocrystallization of aluminized surface of carbon steel for enhanced resistances to corrosion and corrosive wear

    Aluminizing is often used to improve steel's resistances to corrosion, oxidation and wear. This article reports our recent attempts to further improve aluminized carbon steel through surface nanocrystallization for higher resistances to corrosion and corrosive wear. The surface nanocrystallization was achieved using a process combining sandblasting and recovery heat treatment. The entire surface modification process includes dipping carbon steel specimens into a molten Al pool to form an Al coat, subsequent diffusion treatment at elevated temperature to form an aluminized layer, sandblasting to generate dislocation network or cells, and recovery treatment to turn the dislocation cells into nano-sized grains. The grain size of the nanocrystallized aluminized surface layer was in the range of 20-100 nm. Electrochemical properties, electron work function (EWF), and corrosive wear of the nanocrystalline alloyed surfaces were investigated. It was demonstrated that the nanocrystalline aluminized surface of carbon steel exhibited improved resistances to corrosion, wear and corrosive wear. The passive film developed on the nanocrystallized aluminized surface was also evaluated in terms of its mechanical properties and adherence to the substrate.

  17. Mechanical Properties of Cold-Drawn Low Carbon Steel for Nail Manufacture: Experimental Observation

    N.A. Raji

    2013-01-01

    Full Text Available The objective of this study is to investigate the influence of service situation on the mechanical properties of plain nails manufactured from low carbon steel. The influence of the degree of cold drawing on the mechanical properties and strain hardening of the material is investigated by tensile test experimentation. The stress-strain relationships of the cold-drawn low carbon steel were investigated over the 20, 25, 40 and 55% degree of drawn deformation for the manufacture of 4, 3, 2½ and 2 inches nails, respectively. The true stress-strain curves were analyzed to obtain the yield strength and tensile strength of the cold drawn steel. It is shown that the yield strength, tensile strength, hardness and toughness of the low carbon steel reduce with increasing degree of cold-drawn deformation. The micrographs of the deformed samples obtained using optical microscope shows that the grain structure elongates in the direction of the drawing operation and misorientation of the grains set in at 40 and 55% degree of deformation. The difference in yield strength was attributed to the strain hardening, resulting from the different degrees of drawn deformation.

  18. The anaerobic corrosion of carbon steel in alkaline media - Phase 2 results

    In the Belgian Super-container concept a carbon steel overpack will surround high-level waste and spent fuel containers and be encased in a cementitious buffer material. A programme of research was carried out to investigate and measure the rate of anaerobic corrosion of carbon steel in an artificial alkaline pore water that simulates the aqueous phase in the cementitious buffer material. The corrosion rates were measured by monitoring hydrogen evolution using a manometric gas cell technique and by applying electrochemical methods. Phase 2 of the programme has repeated and extended previous Phase 1 measurements of the effects of radiation, temperature and chloride concentration of the anaerobic corrosion rate. This paper provides an update on the results from Phase 2 of the programme. The results confirm previous conclusions that the long-term corrosion rate of carbon steel in alkaline simulated pore water is determined by the formation of a thin barrier layer and a thicker outer layer composed of magnetite. Anaerobic corrosion of steel in cement requires an external supply of water. (authors)

  19. Nanocrystallization of aluminized surface of carbon steel for enhanced resistances to corrosion and corrosive wear

    Chen, C. [Dept. of Materials Physical and Chemical, University of Science and Technology Beijing, Beijing 100083 (China); Dept. of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 (Canada); Li, D.Y., E-mail: dongyang.li@ualberta.c [Dept. of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 (Canada); Shang, C.J. [Dept. of Materials Physical and Chemical, University of Science and Technology Beijing, Beijing 100083 (China)

    2009-12-15

    Aluminizing is often used to improve steel's resistances to corrosion, oxidation and wear. This article reports our recent attempts to further improve aluminized carbon steel through surface nanocrystallization for higher resistances to corrosion and corrosive wear. The surface nanocrystallization was achieved using a process combining sandblasting and recovery heat treatment. The entire surface modification process includes dipping carbon steel specimens into a molten Al pool to form an Al coat, subsequent diffusion treatment at elevated temperature to form an aluminized layer, sandblasting to generate dislocation network or cells, and recovery treatment to turn the dislocation cells into nano-sized grains. The grain size of the nanocrystallized aluminized surface layer was in the range of 20-100 nm. Electrochemical properties, electron work function (EWF), and corrosive wear of the nanocrystalline alloyed surfaces were investigated. It was demonstrated that the nanocrystalline aluminized surface of carbon steel exhibited improved resistances to corrosion, wear and corrosive wear. The passive film developed on the nanocrystallized aluminized surface was also evaluated in terms of its mechanical properties and adherence to the substrate.

  20. Wear Resistance of Carbon Steels and Structure Parameters of Their Surface Layer After High Current Density Sliding

    Fadin, V. V.; Aleutdinova, M. I.

    2016-04-01

    Dry sliding of carbon steels under the action of an AC current of a contact density higher than 100 A/cm2 is realized. It is shown that the contact layer is easily deteriorated in high-carbon steels. This becomes evident as lower wear resistance compared to that of low-carbon steels. There are signs of a developing liquid phase on the worn surface. Using the methods of Auger spectroscopy and X-ray diffraction analysis, it is demonstrated that a high content of carbon in the initial steel structure gives rise to formation of a large amount of γ-Fe (and)as well to a high concentration of carbon near the sliding surface.

  1. Holographic interferometry as electrochemical emission spectroscopy of carbon steel in seawater with low concentration of RA-41 corrosion inhibitor

    In the present investigation, holographic interferometry was utilized for the first time to determine the rate change of the number of the fringe evolutions during the corrosion test of carbon steel in blank seawater and with seawater with different concentrations of a corrosion inhibitor. In other words, the anodic dissolution behaviors (corrosion) of the carbon steel were determined simultaneously by holographic interferometry, an electromagnetic method, and by the electrochemical impedance (EI) spectroscopy, an electronic method. So, the abrupt rate change of the number of the fringe evolutions during corrosion test (EI) spectroscopy, of the carbon steel is called electrochemical emission spectroscopy. The corrosion process of the steel samples was carried out in blank seawater and seawater with different concentrations, 5-20 ppm, of RA-41 corrosion inhibitor using the EI spectroscopy method, at room temperature. The electrochemical emission spectra of the carbon steel in different solutions represent a detailed picture of the rate change of the anodic dissolution of the steel throughout the corrosion processes. Furthermore, the optical interferometry data of the carbon steel were compared to the data, which were obtained from the EI spectroscopy. Consequently, holographic interferometric is found very useful for monitoring the anodic dissolution behaviors of metals, in which the number of the fringe evolutions of the steel samples can be determined in situ. (Author)

  2. Dimensional changes during sintering of manganese-carbon steel compacts

    Sintering behaviour in high purity hydrogen of Hoeganaes Nc 100.24 iron powder with carbon and two different types of ferromanganese additions was investigated. The influence of different manganese contents (3.0 and 4.0 wt. %), type of ferromanganese used (low and high carbon) and isothermal sintering temperature (1120, 1240 and 1300 oC) on dimensional changes was investigated by dilatometry. It is shown that the dimensional changes occurring during heating and isothermal sintering and the final density of sintered compacts are influenced by manganese and carbon through their interactions with the base iron. The results assist in the choice of industrial sintering conditions when the requirement is very small dimensional changes of compacts for s range of manganese and carbon contents. (author)

  3. Effect of Silicon and Manganese on Mechanical Properties of Low-Carbon Plain TRIP Steel

    LI Zhuang; WU Di; HU Rong

    2005-01-01

    A great deal of stabilized retained austenite can be obtained by means of austempering immediately after intercritical annealing in the low-carbon plain steel sheets which only contain alloying elements of silicon and manganese. Transformation from retained austenite to martensite may be induced by strain at a temperature ranging from 50 ℃ to 400 ℃ during tension testing. Transformation-induced plasticity (TRIP) may occur. Alloying of silicon improves the stability of retained austenite. Mechanical properties of the present TRIP steels containing manganese increase with increasing silicon amount when the amount of silicon is less than two percent.

  4. Reliability of Electrochemical Techniques for Determining Corrosion Rates on Carbon Steel in Sulfide Media

    Hilbert, Lisbeth Rischel; Hemmingsen, T.; Nielsen, Lars Vendelbo; Richter, S.

    2007-01-01

    Effects of film formation on carbon steel in hydrogen sulfide (H2S) media may corrupt corrosion rate monitoring by electrochemical techniques. Electrochemical data from H2S solutions, biological sulfide media, and natural sulfide containing geothermal water have been collected, and the process of...... biofilm in combination with ferrous sulfide corrosion products cover the steel surface. Corrosion rates can be overestimated by a factor of 10 to 100 with electrochemical techniques - both by linear polarization resistance (LPR) and electrochemicel impedance spectroscopy (EIS). Oxygen entering the system...

  5. Heat treatment and mechanical stability behaviour of medium-carbon TRIP-aided bainitic steel

    A. Grajcar

    2008-09-01

    Full Text Available bainitic transformation on the mechanical stability of retained austenite for medium-carbon TRIP-aided steel.Design/methodology/approach: The examinations were carried out on medium-carbon steel containing 0.55%C and 1.35%Si. The conditions of heat treatment consisted of isothermal quenching of the specimens to a temperature range of 250 to 550°C, where they were held for 600 and 1800 s. Tensile deformation of steel to the given strain equal 0.25, 0.5 and 0.75 of total elongation of samples was conducted in order to determine the kinetics of retained austenite transformation into martensite. The retained fraction of the γ phase was determined by the use of the quantitative X-ray phase analysis.Findings: Increasing the carbon concentration to 0.55% in TRIP-type steels makes possible to obtain very high strength properties without a deterioration of the ductility. The retained austenite of the 19% volume fraction can be obtained after the isothermal quenching of the steel to a temperature of 250°C. In these conditions, the matrix of the steel is the ferritic bainite. The size of regular grains of retained austenite is equal up to 3μm, while the rest of γ phase is present in a form of thin films between individual laths of bainite. Diversification of retained austenite form has a reflection in its mechanical stability, connected with two-stage kinetics of martensitic transformation of γ phase.Research limitations/implications: To determine with more detail the stability of retained austenite the knowledge of lattice parameter changes with an isothermal holding temperature is needed.Practical implications: The proposed heat treatment can be useful for manufacturing reinforced structural elements characterized by high strength and ductile properties in the automobile industry.Originality/value: The developed conditions of the heat treatment concern the medium-carbon TRIP-type bainitic steel, offering higher product of UTS UEl compared with

  6. The Influence of Applied Stress Ratio on Fatigue Strength of TiN-coated Carbon Steel

    Shiozawa, Kazuaki; Nishino, Seiichi; Handa, Keiichi

    1992-01-01

    The influence of applied stress ratio on the fatigue strength of carbon steel coated with TiN was studied on the basis of measurement of crack initiation with the D. C. potential method. Fatigue tests were performed under the stress ratios of R=0 and -1 in air using the round notched specimens of O.37%C steel, JIS S35C, normalized and coated with TiN by physical vapor deposition (PVD) and chemical vapor deposition (CVD). From the experimental results, increase in fatigue strength was observed...

  7. Ni-P-SiC composite coatings electroplated on carbon steel assisted by mechanical attrition

    2010-01-01

    Ni-P-SiC composite coatings were electroplated on carbon steel substrate assisted by mechanical attrition(MA).The MA action was conducted by dispersing glass balls on the cathodic surface,vibrating in the horizontal direction.The experimental results show that,under the assistant of MA action,the adhesion of Ni-P-SiC coating on the steel substrate can be improved effectively,and the Ni-P-SiC coatings exhibit a crystallized structure and Ni-P matrix can combine tightly with SiC particles,and the hardness and...

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

    Carreño, J. A.; Uribe, I.; Carrillo, J. C.

    2003-01-01

    A model is presented to evaluate the effect of the roughness and the profile of concentration of hydrogen in a low carbon steel. The model takes advantage of the Fick's Second Law, to predict the transport of hydrogen in the steel. The problem is treated as a variational one and its space solution is made numerically by means of the Finite Elements Method, while the temporal equation is solved via the Finite Differences Method, in order to determine the concentration profiles of Hydrogen in t...

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

    Mazur, M.; R. Bogucki; Pytel, S.

    2010-01-01

    The influence of molybdenum content on the process of stress corrosion of ultra-low carbon structural steels with the addition of copper HSLA (High Strength Low Alloy) was analyzed. The study was conducted for steels after heat treatment consisting of quenching andfollowing tempering at 600°C and it was obtained microstructure of the tempered martensite laths with copper precipitates and the phaseLaves Fe2Mo type. It was found strong influence of Laves phase precipitate on the grain boundarie...

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

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

    2008-01-01

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

  11. Effect of asymmetric rolling with cone-shaped rolls on microstructure of low-carbon steel

    A. D. Mekhtiev; Azbanbayev, E. M.; Isagulov, A. Z.; A. R. Karipbayeva; Sv. S. Kvon; Zakariya, N. B.; N. Z. Yermaganbetov

    2015-01-01

    Effect of asymmetric rolling with cone-shaped rolls (ARCSR) on the evolution of microstructure of low-carbon steel was investigated. Steel containing 0,15 % C (wt. %) billet with initial grain size of 60 μm was deformed up to thickness of 5 mm with diameters ratio of 1,5, as well as in cylindrical rolls. Rolling was conducted at three different temperatures: 900 °C, 1 000 °C and 1 100 °C. Final thickness is obtained through four passes of ARCSR with total reduction of 61,7 %. It has been show...

  12. Non-metallic inclusions structure dimension in high quality steel with medium carbon contents

    T. Lipiński

    2009-07-01

    Full Text Available The experimental material consisted of semi-finished products of high-grade, medium-carbon structural steel. The production process involved two melting technologies: steel melting in a 140-ton basic arc furnace with desulfurization and argon refining variants, and in a 100-ton oxygen converter. Billet samples were collected to analyze the content of non-metallic inclusions with the use of an optical microscope and a video inspection microscope. The results were processed and presented in graphic form.

  13. Electron-beam heat treatment of thin band of low-carbon steel

    Using the methods of raster electron microscopy, X-ray structural and chemical analysis and also X-ray microanalysis, the change was studied in the mechanical properies of a band made of low-carbon steel 08 kp that takes place after electron-beam heat treatment. It has been shown that the above change is due to a specific character of the α reversible γ phase transition. After electron-beam treatment under optimum conditions, the properties of the band made of steel 08 kp and 0.15 mm thick (plasticity, ultimate strength, etc.) are similar to those obtained using the conventional procedures (annealing and skin pass rolling)

  14. Tribological Properties of WS2 Nanoparticles Lubricants on Aluminum-Silicon Alloy and Carbon Steels

    Riyadh A. AL-SAMARAI; Yarub AL-DOURI; Haftirman HAFTIRMAN; Khiarel Rafzi AHMAD

    2013-01-01

    The rheological properties of nanometric tungsten disulphide (WS2) nanoparticles oil lubricants and its tribological performance with two hypereutectic Al-Si alloy and carbon steel are examined. These two oils are used to reduce wear and friction and to explore the actions via tribological pin-on-disk tests. The pin was made from hypereutectic Al-Si alloy on steel disk, taking into consideration the effect of loads (10, 20, 30 N) and different speed (200, 300, 400 rpm). Oils with and without ...

  15. The performance of a surface-applied corrosion inhibitor for the carbon steel in saturated Ca(OH)2 solutions

    In the present work, the performance of an amino alcohol based surface applied inhibitor was studied by the electrochemical techniques in saturated Ca(OH)2 solutions. The surface morphology of the carbon steel was observed by scanning electron microscope, and the energy diffraction spectrum was also tested. Results showed that the inhibitor used in this work demonstrated obvious inhibition efficiency on the carbon steel in saturated Ca(OH)2 solutions. The inhibition mechanism of the inhibitor lies in the quick adsorption of the active component on carbon steel surface

  16. Steel

    Composition of age hardening steel, % : Fe - (12.0-12.4) Cr - (2-2.7) Ni (0.5-0.6) Ti - (1.0-1.2) Mn - (0.03 - 0.04) C having high values of magnetoelastic internal friction and mechanical properties as well as an ability to operate under the conditions of alternating loadings are proposed. Damping properties of the steel permit to improve labour conditions. Data for the above steel on internal friction, impact strength and tensile properties are given

  17. Performance evaluation for carbonation of steel-making slags in a slurry reactor

    CO2 sequestration by the aqueous carbonation of steel-making slag under various operational conditions was investigated in this study. The effects of the operational conditions, including type of steel-making slag, reaction time, reaction temperature, and CO2 flow rate, on the performance of the carbonation process were evaluated. The results indicated that the BOF slag had the highest carbonation conversion, approximately 72%, at a reaction time of 1 h, an operating pressure of 101 kPa and a temperature of 60 oC due to its higher BET surface area of BOF slag compared to UF, FA, and BHC slags. The major factors affecting the carbonation conversion are reaction time and temperature. The reaction kinetics of the carbonation conversion can be expressed by the shrinking-core model. The measurements of the carbonated material by the SEM and XRD instruments provide evidence indicating the suitability of using the shrinking-core model in this investigation. Comparison of the results with other studies suggests that aqueous carbonation by slurry reactor is viable due to its higher mass transfer rate.

  18. Performance evaluation for carbonation of steel-making slags in a slurry reactor.

    Chang, E-E; Chen, Chung-Hua; Chen, Yi-Hung; Pan, Shu-Yuan; Chiang, Pen-Chi

    2011-02-15

    CO(2) sequestration by the aqueous carbonation of steel-making slag under various operational conditions was investigated in this study. The effects of the operational conditions, including type of steel-making slag, reaction time, reaction temperature, and CO(2) flow rate, on the performance of the carbonation process were evaluated. The results indicated that the BOF slag had the highest carbonation conversion, approximately 72%, at a reaction time of 1h, an operating pressure of 101 kPa and a temperature of 60°C due to its higher BET surface area of BOF slag compared to UF, FA, and BHC slags. The major factors affecting the carbonation conversion are reaction time and temperature. The reaction kinetics of the carbonation conversion can be expressed by the shrinking-core model. The measurements of the carbonated material by the SEM and XRD instruments provide evidence indicating the suitability of using the shrinking-core model in this investigation. Comparison of the results with other studies suggests that aqueous carbonation by slurry reactor is viable due to its higher mass transfer rate. PMID:21168964

  19. Electrochemical and Dry Sand Impact Erosion Studies on Carbon Steel.

    Naz, M Y; Ismail, N I; Sulaiman, S A; Shukrullah, S

    2015-01-01

    This study investigated the dry and aqueous erosion of mild steel using electrochemical and dry sand impact techniques. In dry sand impact experiments, mild steel was eroded with 45 μm and 150 μm sand particles. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and micro-hardness techniques were used to elaborate the surface morphology of the eroded samples. The results revealed significant change in morphology of the eroded samples. In-depth analysis showed that although the metal erosion due to larger particles was significantly higher, the fines also notably damaged the metal surface. The surface damages were appreciably reduced with decrease in impact angle of the accelerated particles. The maximum damages were observed at an impact angle of 90°. The hardness of the samples treated with 45 μm and 150 μm sand remained in the range of 88.34 to 102.31 VHN and 87.7 to 97.55 VHN, respectively. In electrochemical experiments, a triple electrode probe was added into the metal treatment process. The linear polarization resistance (LPR) measurements were performed in slurries having 5% (by weight) of sand particles. LPR of the samples treated with 45 μm and 150 μm sand slurries was calculated about 949 Ω.cm(2) and 809 Ω.cm(2), respectively. PMID:26561231

  20. Electrochemical and Dry Sand Impact Erosion Studies on Carbon Steel

    Naz, M. Y.; Ismail, N. I.; Sulaiman, S. A.; Shukrullah, S.

    2015-11-01

    This study investigated the dry and aqueous erosion of mild steel using electrochemical and dry sand impact techniques. In dry sand impact experiments, mild steel was eroded with 45 μm and 150 μm sand particles. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and micro-hardness techniques were used to elaborate the surface morphology of the eroded samples. The results revealed significant change in morphology of the eroded samples. In-depth analysis showed that although the metal erosion due to larger particles was significantly higher, the fines also notably damaged the metal surface. The surface damages were appreciably reduced with decrease in impact angle of the accelerated particles. The maximum damages were observed at an impact angle of 90°. The hardness of the samples treated with 45 μm and 150 μm sand remained in the range of 88.34 to 102.31 VHN and 87.7 to 97.55 VHN, respectively. In electrochemical experiments, a triple electrode probe was added into the metal treatment process. The linear polarization resistance (LPR) measurements were performed in slurries having 5% (by weight) of sand particles. LPR of the samples treated with 45 μm and 150 μm sand slurries was calculated about 949 Ω.cm2 and 809 Ω.cm2, respectively.

  1. Detection of Signals of Mock-up Pipes of Carbon Steel and Stainless Steel using Guided Ultrasonic Waves due to Magnetostrictive Sensors

    A piping mock-up with a diameter of 6 inch and schedule number 80 of carbon steel and stainless steel were fabricated. The signals of weldments of these pipes were detected with a torsional vibration mode of frequency of 32 kHz using sensors, such as a pure Ni or a 49Fe-49Co-2V alloy strip. The signals from the 49Fe-49Co-2V alloy strip sensor were more detectable than those from the Ni strip sensor. The signals of 49Fe-49Co-2V alloy strip sensor of tile stainless steel piping mock-up were more detectable than those of 49Fe-49Co-2V alloy strip sensor of the carbon steel piping mock-up.

  2. A Study of Electrochemical Protection of Carbon Steels in Sulfuric Acid Solutions - Electrochemical Protection Diagrams of Metals (1) -

    Electrochemical protection of carbon steels was studied in sulfuric acid solutions. The main results obtained are as follows: 1) Electrochemical protection diagrams of carbon steels in sulfuric acid solutions can be drawn with the data from Jeon's determination method of the optimum cathodic protection potential, the Tafel extrapolation and the characteristics of anodic polarization curves, and the diagram also represent various practical protection data. 2) Corrosion rates of carbon steels in the more concentration than 45% solutions are very low because they are on sulfaction or passivation in the solution, but the rates in the less concentration than the solutions are very high since they are on activation. 3) SS 41 steel is suitable in the more concentration than 45% solutions but SM 50 steel is relatively good in the less concentration than the solutions from the economical view

  3. Influence of hydroxyis, carbonates and chiorides ions on the pitting corrosión of steel in concrete

    Chaussadent, Thierry; Dron, Roger

    1992-01-01

    The electrochemical process of steel corrosion in concrete are studied by simulating its liquid phase with synthetical solutions in a large range of hydroxyls, carbonates and chlorides ions.The steel specimen is either under or without an electrical polarization. The present analysis has made it possible to define a new relevant parameter, which is the [CΓ]/[AIK] ratio (where AIK is the total alkalinity). It characterizes the conditions of the polarized steel pitting corrosion. Fu...

  4. 77 FR 64465 - Circular Welded Carbon-Quality Steel Pipe From the United Arab Emirates: Final Affirmative...

    2012-10-22

    ... Duties; Countervailing Duties, 62 FR 27296, 27323 (May 19, 1997), and See Circular Welded Carbon-Quality... International Trade Administration Circular Welded Carbon-Quality Steel Pipe From the United Arab Emirates... countervailable subsidies are being provided to producers and exporters of circular welded carbon-quality...

  5. Effect of the dendritic morphology on hot tearing of carbon steels

    Ridolfi, M. R.

    2016-03-01

    Hot tears form during solidification in the brittle region of the dendritic front. Most hot tearing criteria are based on solid and fluid mechanics, being the phenomenon strictly depending on the solid resistance to applied strains and on the liquid capability of filling the void spaces. Modelling both mechanisms implies the precise description of the dendritic morphology. To this scope, the theory of coalescence of the dendritic arms at grain boundaries of Rappaz et al. has been applied, in this work, to the columnar growth of carbon steels by means of a simple mathematical model. Depending on the alloy composition, solid bridging starts at solid fractions down to about 0.8 and up to above 0.995 (very low carbon). The morphology of the brittle region changes drastically with increasing carbon and adding other solutes. In particular, ferritic dendrites, typical of low carbon steels, tend to offer short and wide interdendritic spaces to the surrounding liquid making possible their complete filling, and few solid bridges; peritectic steels show the rise of austenite growing and bridging rapidly in the interdendritic spaces, preventing void formation; austenitic dendrites form long and narrow interdendritic spaces difficult to reach for the liquid and with a lot of solid bridges. Sulphur addition mainly acts in delaying the coalescence end, more markedly in ferritic dendrites.

  6. Enhanced wear resistance of production tools and steel samples by implantation of nitrogen and carbon ions

    In recent years ion implantation has become a feasible technique for obtaining improved wear resistance of production tools. However, basic knowledge of how and in which cases ion implantation is working at its best is still needed. The present paper discusses structural and tribological investigations of carbon and nitrogen implanted steels. The nitrogen data were obtained mainly from field tests and the investigation of carbon implantations took place mainly in the laboratory. A study was made of how the tribological behaviour of implanted steels changes with different implantation parameters. The tribological laboratory investigations were carried out using pin-on-disc equipment under controlled test conditions, and deal with high dose carbon implantation (approximately (1-2)x1018 ions cm-2). The wear resistance of steels was enhanced dramatically, by up to several orders of magnitude. The field test results cover a broad range of ion implanted production tools, which showed a marked improvement in wear resistance. Nitrogen implanted tools are also compared with carbon and titanium implanted tools. (orig.)

  7. 75 FR 47541 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products from Brazil and Japan: Final Results of...

    2010-08-06

    ...) of the Act. See Initiation of Five-Year (``Sunset'') Review, 75 FR 16437 (April 1, 2010). The...-free (IF)) steels, high strength low alloy (HSLA) steels, and the substrate for motor lamination steels... and/or niobium added to stabilize carbon and nitrogen elements. HSLA steels are recognized as...

  8. Effect of carbon content on microstructure and mechanical properties of hot-rolled low carbon 12Cr-Ni stainless steel

    Research highlights: → Hot-rolled ultra low carbon martensite is characterized by dislocation cells substructure. → The formation of dislocation cells is attributed to high Ms and low interstitial atoms content. → Hot-rolled ultra low carbon 12Cr-Ni stainless steel has excellent impact toughness. → Delta ferrite deteriorates the impact toughness of hot-rolled 12Cr-Ni stainless steel. - Abstract: 12Cr-Ni stainless steels containing different carbon contents from 0.004 wt.% to 0.034 wt.% were hot-rolled and air-cooled. Their corresponding microstructures were observed with optical microscope and transmission electron microscope, and the Vickers hardness, tensile and impact tests were also carried out. It was found that the martensitic morphology was significantly influenced by carbon content. The as-received ultra low carbon martensite in the steel containing 0.004 wt.% C is characterized by dislocation cells substructure. The formation of dislocation cells is attributed to high martensite finishing point (above 400 deg. C) and low interstitial atoms content. On the other hand, the martensite in the steel containing 0.034 wt.% C consists mainly of typical martensite laths because of low martensite finishing point and high interstitial atoms content which hinder dislocation motion. Furthermore, carbon content has an evident effect on the mechanical properties of 12Cr-Ni steels. The hardness and strength of the as-received steels increase with an increase in carbon content, but their elongation and impact toughness decrease with the carbon content. The steel containing 0.004 wt.% C has excellent impact toughness due to the ultra low carbon content in the martensite composed of dislocation cells.

  9. Mechanical properties and warm prestress of ultra-low carbon steel at 4 K

    The yield strength of ultra-low carbon steel increases from 137 MPa at 295 K to 705 MPa at 4 K. In liquid helium the material is brittle and cleaves in tension. Consequently it is difficult or impossible to properly fatigue-precrack toughness specimens for tests at 4 K. The authors precracked a series of compact specimens at room temperature and then fractured them at 4 K. The toughness measurements at 4 K are affected by precracking at 295 K, and they provide only an estimate of KIC for this steel: 15 MPa·m1/2. The tensile properties of the steel at 295 and 4 K are reported, and the effects of prestress on the tensile and fracture properties at 4 K are discussed

  10. Weldability of 1 000 MPa Grade Ultra-low Carbon Bainitic Steel

    Qing-mei JIANG; Xiao-qiang ZHANG; Li-qing CHEN

    2016-01-01

    Maximum hardness test in weld heat-affected zone (HAZ),oblique Y-groove cracking test and mechanical property test of welding joint of 1 000 MPa grade ultra-low carbon bainitic steel were carried out,so as to research the weldability of the steel.The results show that the steel has lower cold cracking sensitivity,and preheating tem-perature of 100 ℃ can help completely eliminate cold cracks,generating good process weldability.The increase of preheating temperature can reduce the hardening degree of heat-affected zone.The strength of welding joint decreases and hardness reduces when heat inputs increase,and excellent mechanical properties can be obtained when low weld-ing heat inputs are used.Fine lath bainites of different orientations combined with a few granular bainites that effec-tively split the original coarse austenite grains are the foundation of good properties.

  11. Modelling of Nb influence on phase transformation behaviours from austenite to ferrite in low carbon steels

    Wang, L.; Parker, S. V.; Rose, A. J.; West, G. D.; Thomson, R. C.

    2016-03-01

    In this paper, a new model has been developed to predict the phase transformation behaviours from austenite to ferrite in Nb-containing low carbon steels. The new model is based on some previous work and incorporates the effects of Nb on phase transformation behaviours, in order to make it applicable for Nb-containing steels. Dissolved Nb atoms segregated at prior austenite grain boundaries increase the critical energy for ferrite nucleation, and thus the ferrite nucleation rate is decreased. Dissolved Nb atoms also apply a solute drag effect to the moving transformation interface, and the ferrite grain growth rate is also decreased. The overall transformation kinetics is then calculated according to the classic Johnson-Mehl-Avrami-Kolmogorov (JMAK) theory. The new model predictions are quite consistent with experimental results for various steels during isothermal transformations or continuous cooling.

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

    Hao Yu; Yonglin Kang

    2008-01-01

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

  13. Enhancing the Mechanical Properties and Formability of Low Carbon Steel with Dual-Phase Microstructures

    Habibi, M.; Hashemi, R.; Sadeghi, E.; Fazaeli, A.; Ghazanfari, A.; Lashini, H.

    2016-02-01

    In the present study, a special heat treatment cycle (step quenching) was used to produce a dual-phase (DP) microstructure in low carbon steel. By producing this DP microstructure, the mechanical properties of the investigated steel such as yield stress, tensile strength, and Vickers hardness were increased 14, 55, and 38%, respectively. In order to investigate the effect of heat treatment on formability of the steel, Nakazima forming test was applied and subsequently finite element base modeling was used to predict the outcome on forming limit diagrams. The results show that the DP microstructure also has a positive effect on formability. The results of finite element simulations are in a good agreement with those obtained by the experimental test.

  14. Electrochemical impedance spectrometry using 316L steel, hastelloy, maraging, Inconel 600, Elgiloy, carbon steel, TiN and NiCr. Simulation in tritiated water. 2 volumes

    Polarization and electrochemical impedance spectrometry curves are presented and discussed. These curves make it possible to ascertain the corrosion domains and to compare the slow and fast kinetics (voltammetry) of different stainless steel alloys. These corrosion kinetics, the actual or simulated tritiated water redox potentials, and the corrosion potentials provide a classification of the steels studied here: 316L, Hastelloy, Maraging, Inconel 600, Elgiloy, carbon steel and TiN and NiCr deposits. From the results it can be concluded that Hastelloy and Elgiloy have the best corrosion resistance. (author). 49 refs., 695 figs., tabs

  15. Influences of Spray Parameters on the Structure and Corrosion Resistance of Stainless Steel Layers Coated on Carbon Steel by Plasma Spray Treatment

    Stainless steel powders were sprayed on the grit-blasted SM45C carbon steel substrates using a plasma spray method. The influences of the spray parameters on the structure and corrosion resistance of the layers coated on the carbon steel were investigated. Corrosion behavior of the layers were analyzed by the anodic polarization tests in deaerated 0.1 M NaCl + 0.01 M NaOH solution at 80 .deg. C. The surface roughness and porosity were observed to decrease with decreasing the particle size. The surface hardness of the coating was always higher than that of the matrix, SM45C, implying that the higher resistance of the coating to erosion-corrosion than that of matrix, and increased as the spray power and the spray distance increase. Stainless steel coats showed more corrosion resistance than the carbon steel did, due to their passivity. The corrosion resistance of the coats, however, were inferior to that of the bulk stainless steels due to the inherent defects formed in the coats. The defects such as rough surface and pores provided the occluded sites favorable for the initiation of localized corrosion, resulting in the conclusion that finer the powder is, higher the corrosion resistance is. And the Cr oxides formation resulting in Cr depletion around the oxides reduced the corrosion resistance of the coats

  16. 77 FR 43806 - Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's Republic of...

    2012-07-26

    ... International Trade Administration Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the... Administrative Reviews and Request for Revocation in Part, 76 FR 82268 (December 30, 2011). The review covers 32... Charging Development Co., Ltd.; Wuxi Resources Steel Making Co., Ltd.; Wuxi Seamless Special Pipe Co.,...

  17. Effects of niobium addition on the structure and properties of medium and high carbon steels. v. 1,2

    An evaluation about the use of niobium in medium and high carbon steels, with ferritic-pearlitic structure, through the understanding of niobium actuaction mechanism in the structure, and consequently in the mechanical properties of those steels is done. (E.G.)

  18. 76 FR 55004 - Certain Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Preliminary...

    2011-09-06

    ..., 75 FR 55769 (September 14, 2010) (unchanged in CORE 16 Final Results); Certain Corrosion-Resistant... for Revocation in Part, 75 FR 60076, 60077 (September 29, 2010) (Initiation Notice). In addition... Carbon Steel Flat Products from Korea, 58 FR 44159 (August 19, 1993) (Orders on Certain Steel from...

  19. 75 FR 55769 - Certain Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Notice of...

    2010-09-14

    ... for Revocation in Part, 74 FR 48224, 48225 (September 22, 2009) (Initiation Notice). In addition... Carbon Steel Flat Products from Korea, 58 FR 44159 (August 19, 1993) (Orders on Certain Steel from Korea..., Finding, or Suspended Investigation; Opportunity to Request Administrative Review, 74 FR 38397 (August...

  20. Determination of Cr, Mn, Si, and Ni in carbon steels by optical emission spectrometry with spark source

    Elemental composition of steels determines some important of his characteristic moreover it is necessary to obtain their quality certification. Analytical procedure has performed for determination of Cr, Mn, Si and Ni in carbon steels by optical emission spectrometry with spark source. reproducibility of results is 5-11 %. Exactitude has tested with results that have obtained by internationally recognised methods-