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Sample records for carbon steel nuclear

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

  3. Microbiologically influenced corrosion of carbon steel from secondary circuit of nuclear power plant

    International Nuclear Information System (INIS)

    Microbiologically influenced corrosion (MIC) is the initiation or acceleration of the corrosion due to the interaction between the microbial activity and the corrosion processes. During 1980s , the electric power industry, particularly the nuclear industry , has devoted increased attention to MIC that affect reliability, operating and maintenance costs of plant systems. The economic impact of failures in such systems in large nuclear units can be extremely costly, about USD 1,000,000 per day. Costs for chemicals and delivery systems for water treatments to prevent MIC and biofouling can approach about USD 1,000,000 per year. Several plants have been forced to undertake replacement or to make extensive repairs of their service water system at a cost of about USD 30,000,000 per plant. Nuclear power plant can exhibit MIC as a result of their basic design philosophy. The large number of stand-by and redundant systems in nuclear plant design establishes stagnant or intermittent flow conditions, a situation in which a number of systems, some of which are safety-related, will be susceptible to MIC. The large size of nuclear generating facilities and the often prolonged licensing process has resulted in an extended construction phase, often with structural materials in contact with stagnant, untreated water used for hydrostat testing. This also produces a condition amenable to microbial growth. Carbon steels may experience random pitting, general corrosion, or severe degradation in flow as a result of MIC. Tubercles (comprising corrosion products, microbes, sticky exopolymer associated with both living and dead cells, and debris) often form on carbon steel pipes and other components. The tubercles create a hydraulic resistance to cooling water flow as well as sites for additional microbial activity. Tubercles can grow together, eventually becoming a severe impediment to cooling water flow. Pitting is also often observed beneath tubercles as mechanical and chemical

  4. Semi-empirical model for carbon steel corrosion in long term geological nuclear waste disposal

    International Nuclear Information System (INIS)

    In France and other countries, carbon and low alloy steels have been proposed as suitable materials for nuclear waste containers for long term geological disposal since, for such types of steels, general and localised corrosion can be fairly well predicted in geological environments (mainly argillaceous and granitic conditions) during the initial oxic and the following anoxic stages. This paper presents a model developed for the long term estimation of general and localised corrosion of carbon steel in argillaceous and granitic environments. In the case of localised corrosion, the model assumes that pitting and crevice corrosion propagation rates are similar. The estimations are based on numerous data coming from various experimental programmes conducted by the following laboratories: UKAEA (United Kingdom); NAGRA (Switzerland); SCK-CEN (Belgium); JNC (Japan) and ANDRA-CEA-EDF (France). From these data, the corrosion rates measured over long periods (from six months to several years) and derived from mass loss measurements have been selected to construct the proposed models. For general corrosion, the model takes into account an activation energy deduced from the experimental results (Arrhenius law) and proposes three equations for the corrosion rate: one for the oxic conditions, one for the early stage of the anoxic conditions and one for the long term anoxic corrosion. Concerning localised corrosion, a semi-empirical model, based on the evolution of the pitting factor (ratio between the maximum pit depth and the average general corrosion depth) as a function of the general corrosion depth, is proposed. This model is compared to other approaches where the maximum pit depth is directly calculated as a function of time, temperature and oxic or anoxic conditions. Finally, the presented semi-empirical models for long term corrosion estimation are applied to the case of nuclear waste storage. The results obtained by the different methods are then discussed and compared

  5. The kinetics of pitting corrosion of carbon steel applied to evaluating containers for nuclear waste disposal

    International Nuclear Information System (INIS)

    This is the final summary report on a project, funded by SKB, investigating the pitting corrosion of carbon steel containers for high level nuclear waste or spent reactor fuel under granite disposal conditions. The study has covered a statistically based experimental programme to establish the pit growth kinetics, and a modelling study to determine the maximum pitting period subsequent to repository closure. It is shown that the rate of pit propagation is slower than that suggested by earlier work and that the maximum pitting period is only a small fraction of the target container life of 1000 years. An illustrative example of the methodology for estimating the corrosion allowance needed to prevent pit penetration is given. This could be applied to specific repository conditions as defined by SKB. Finally some limited recommendations are made for further studies to test and validate the methodology. (au)

  6. Influence of the pH and Temperature on Carbon Steel in the Secondary System of Nuclear Power Plants

    International Nuclear Information System (INIS)

    The broken pipes events occurred in the Surry unit 2 nuclear power plant in USA at 2004 and the Mihama unit 3 nuclear power plant in Japan at 1986 caused many casualties. It is mainly generated in the carbon steel pipe of the single-phase or two-phase. Also, most important influential factors of the FAC are known to be flow rate of the fluid, flow, pH, temperature, material contents and shape of the piping. The FAC is caused by the interaction of hydraulics factors and water chemistry factors. It can be mitigated effectually by the control of influential factors. In this study, the corrosion rate influenced by pH and temperature is evaluated in the single-phase by using the secondary system of power plant carbon steel. In this study, the pH and temperature effects on the carbon steel used in nuclear power plant secondary system were evaluated. Most effective factor on the corrosion rate is a solubility of magnetite and hematite produced by reaction between carbon steel and oxygen. The solubility of magnetite and hematite decreases for increasing pH, and it shows the highest value at 150 .deg. C temperature condition and decreases for higher temperature condition than 150 .deg. C. In this study, the experimental tests were performed for nuclear power plant operating condition of high temperature water chemistry environment using carbon steel specimen and static autoclave. The test results are showing consistent with the magnetite solubility trend. The static autoclave test is not able to consider the FAC phenomenon completely

  7. Flow accelerated corrosion of carbon steel piping in nuclear power plants

    International Nuclear Information System (INIS)

    Flow accelerated corrosion (FAC) is a process whereby the normally protective oxide layer on carbon or low alloy steel dissolved into a stream of flowing water resulting in increasing the corrosion rate. Major influencing factors that affect the FAC are flow velocity, temperature, pH, dissolved oxygen concentration, and steel composition. The experimental study described in this paper was focused on evaluating the FAC behavior of carbon steel according to environment conditions. Feasibility tests for the mitigation method against the FAC were also carried out with controlling the water chemistry and with applying the magnetic field. A high temperature rotating cylinder electrode (HTRCE) and a water chemistry control system was developed to perform the electrochemical test in high temperature water environments. The main design concept of HTRCE is to assure stable operation of working electrode in a severe environment, to insulate electrode housing except working electrode surface against external fluid, and to extract corrosion parameter from the rotating cylinder to outside of the autoclave safely. The electrochemical corrosion potential (ECP) and current density were measured as a function of temperature and rotating speed using polarization monitoring. ECP values dropped at a rate of -1.51 mV/.deg. C above 150 .deg. C, which may be come from the formation of magnetite on the steel surface. With increasing rotation of the RCE, the ECP shifted upward in all temperature ranges. This shift may be attributed to the diffusion enhancement of the oxidizing agents in the rapidly flowing of fluid. From the velocity exponent of the cathodic half-cell current density on the steel surface, it was evident that a mass transfer process first dominated the corrosion reaction at 150 .deg. C, and then an activation process partly controlled the corrosion kinetics with increasing temperature. From the results of corrosion experiment at high temperature water, HTRCE has been proved

  8. Nuclear transmutation in steels

    Science.gov (United States)

    Belozerova, A. R.; Shimanskii, G. A.; Belozerov, S. V.

    2009-05-01

    The investigations of the effects of nuclear transmutation in steels that are widely used in nuclear power and research reactors and in steels that are planned for the application in thermonuclear fusion plants, which are employed under the conditions of a prolonged action of neutron irradiation with different spectra, made it possible to study the effects of changes in the isotopic and chemical composition on the tendency of changes in the structural stability of these steels. For the computations of nuclear transmutation in steels, we used a program complex we have previously developed on the basis of algorithms for constructing branched block-type diagrams of nuclide transformations and for locally and globally optimizing these diagrams with the purpose of minimizing systematic errors in the calculation of nuclear transmutation. The dependences obtained were applied onto a Schaeffler diagram for steels used for structural elements of reactors. For the irradiation in fission reactors, we observed only a weak influence of the effects of nuclear transmutation in steels on their structural stability. On the contrary, in the case of irradiation with fusion neutrons, a strong influence of the effects of nuclear transmutation in steels on their structural stability has been noted.

  9. Steels and welding nuclear

    International Nuclear Information System (INIS)

    This ENEA Data-Base regards mechanical properties, chemical composition and heat treatments of nuclear pressure vessel materials: type A533-B, A302-B, A508 steel plates and forgings, submerged arc welds and HAZ before and after nuclear irradiation. Irradiation experiments were generally performed in high flux material test reactors. Data were collected from international available literature about water nuclear reactors pressure vessel materials embrittlement

  10. Ultrahigh carbon steels, Damascus steels, and superplasticity

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-04-01

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

  11. Effect of microstructure of carbon steel on magnetite formation in simulated Hot Conditioning environment of nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. Effect of microstructure of carbon steel on magnetite formation in simulated Hot Conditioning environment of nuclear reactors

    International Nuclear Information System (INIS)

    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

  13. A review of the possible effects of hydrogen on lifetime of carbon steel nuclear waste canisters

    International Nuclear Information System (INIS)

    In Switzerland, the National Cooperative for the Disposal of Radioactive Waste (Nagra) is responsible for developing an effective method for the safe disposal of vitrified high level waste (HLW) and spent fuel. One of the options for disposal canisters is thick-walled carbon steel. The canisters, which would have a diameter of about 1 m and a length of about 3 m (HLW) or about 5 m (spent fuel), will be embedded in horizontal tunnels and surrounded with bentonite clay. The regulatory requirement for the minimum canister lifetime is 1000 years but demonstration of a minimum lifetime of 10,000 years would be desirable. The pore-water to which the canister will be exposed is of marine origin with about 0.1-0.3 M Cl-. Since hydrogen is generated during the corrosion process, it is necessary to assess the probability of hydrogen assisted cracking modes and to make recommendations to eliminate that probability. To that aim, key reports detailing projections for the local environment and associated corrosion rate of the waste canister have been evaluated with the focus on the implication for the absorbed hydrogen concentration in the steel. Simple calculations of hydrogen diffusion and accumulation in the inner compartment of the sealed canister indicate that a pressure equivalent to that for gas pockets external to the canister (envisaged to be about 10 MPa) may be attained in the proposed exposure time, an important consideration since it is not possible to modify the internal surface of the closure weld. Current ideas on mechanisms of hydrogen assisted cracking are assessed from which it is concluded that the mechanistic understanding and associated models of hydrogen assisted cracking are insufficient to provide a framework for quantitative prediction for this application. The emphasis then was to identify threshold conditions for cracking and to evaluate the likelihood that these may be exceeded over the lifetime of the containment. Based on an analysis of data in the

  14. The evaluation of erosion/corrosion problems of carbon steel piping in Taiwan PWR nuclear power plant

    International Nuclear Information System (INIS)

    Taiwan pressurized water reactor (PWR), Maanshan nuclear power plant Units 1 and 2 implemented measurements of the wall thinning of the carbon steel piping under the request of regulation authority to prevent the events due to erosion/corrosion since 1989. At first, the licensee established the comprehensive inspection program by itself. Over 2000 components were inspected per unit and 300-500 pipe components were examined by ultrasonic testing per scheduled outage. The simple predictive methodology determined the operability of each individual piping component in the next fuel cycle. Based on the inspection results, the susceptible pipe components were established. Implementation of effective correction management and an improved inspection program can improve the safety, as well as the efficiency, of long-term reactor operations. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  16. Effect of microstructure of carbon steel on magnetite formation in simulated Hot Conditioning environment of nuclear reactors

    Science.gov (United States)

    Sinha, Prafful Kumar; Kiran Kumar, M.; Kain, Vivekanand

    2015-09-01

    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.

  17. History of ultrahigh carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    Wadsworth, J.; Sherby, O.D.

    1997-06-20

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

  18. Steel structures for nuclear facilities

    International Nuclear Information System (INIS)

    The guide presents requirements on the design and manufacturing of steel structures for nuclear facilities as well as on documents to be submitted to Finnish Radiation and Nuclear Safety Authority (STUK). Inspection of steel structures during plant construction and operation is also described

  19. Corrosion Inhibiting Mechanism of Nitrite Ion on the Passivation of Carbon Steel and Ductile Cast Iron for Nuclear Power Plants

    Directory of Open Access Journals (Sweden)

    K. T. Kim

    2015-01-01

    Full Text Available While NaNO2 addition can greatly inhibit the corrosion of carbon steel and ductile cast iron, in order to improve the similar corrosion resistance, ca. 100 times more NaNO2 addition is needed for ductile cast iron compared to carbon steel. A corrosion and inhibition mechanism is proposed whereby NO2- ion is added to oxidize. The NO2- ion can be reduced to nitrogen compounds and these compounds may be absorbed on the surface of graphite. Therefore, since nitrite ion needs to oxidize the surface of matrix and needs to passivate the galvanic corroded area and since it is absorbed on the surface of graphite, a greater amount of corrosion inhibitor needs to be added to ductile cast iron compared to carbon steel. The passive film of carbon steel and ductile cast iron, formed by NaNO2 addition showed N-type semiconductive properties and its resistance, is increased; the passive current density is thus decreased and the corrosion rate is then lowered. In addition, the film is mainly composed of iron oxide due to the oxidation by NO2- ion; however, regardless of the alloys, nitrogen compounds (not nitrite were detected at the outermost surface but were not incorporated in the inner oxide.

  20. Steels for nuclear power. I

    International Nuclear Information System (INIS)

    The principles are listed of nuclear reactor operation and the reactors are classified by neutron energy, fuel and moderator designs, purpose and type of moderator. The trend and the development of light-water reactor applications are described. The fundamental operating parameters of the WWER type reactors are indicated. The effect is discussed of neutron radiation on reactor structural materials. The characteristics are described of steel corrosion due to the contact of the steel with steam or sodium in the primary coolant circuit. The reasons for stress corrosion are given and the effects of radiation on corrosion are listed. The requirements and criteria are given for the choice of low-alloy steel for the manufacture of pressure vessels, volume compensators, steam generators, cooling conduits and containment. A survey is given of most frequently used steels for pressure vessels and of the mechanical and structural properties thereof. The basic requirements for the properties of steel used in the primary coolant circuit are as follows: sufficient strength in operating temperature, toughness, good weldability, resistance to corrosion and low brittleness following neutron irradiation. The materials are listed used for the components of light-water and breeder reactors. The production of corrosion-resistant steels is discussed with a view to raw materials, technology, steel-making processes, melting processes, induction furnace steel-making, and to selected special problems of the chemical composition of steels. The effects are mainly discussed of lead, bismuth and tin as well as of some other elements on hot working of high-alloy steels and on their structure. The problems of corrosion-resistant steel welding and of pressure vessel cladding are summed up. Also discussed is the question of the concept and safeguards of the safety of nuclear installation operation and a list is presented of most commonly used nondestructive materials testing methods. The current

  1. The effect of minor elements on corrosion resistance of carbon steel for high level nuclear waste disposal container

    International Nuclear Information System (INIS)

    Controlling the reduction of Fe3O4 film is an important factor to improve corrosion resistance of carbon steel for geological disposal of radioactive waste. In the present study, the effect of alloying elements on the reduction reaction of Fe3O4 film was examined using sputter-deposited complex oxide films and low alloy steels containing the alloying elements. Fe3O4 films containing a small amount of another oxides were cathodically polarized in the simulated solution of bentonite-contacting water. It showed that the addition of Cr2O3, TiO2, Al2O3 and MoO2 to Fe3O4 is effective on the suppression of the reductive reaction. Fe3O4 films formed on the steels containing small amount of Cr, Ti, Al and Mo by alkaline solution treatment at high temperature also showed a high resistance against the reductive dissolution. The steels containing these alloying elements showed excellent corrosion resistances in the simulated solution of bentonite-contacting water. (author)

  2. Corrosion of carbon steel welds

    International Nuclear Information System (INIS)

    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)

  3. THE SENSITIVITY OF CARBON STEELS' SUSCEPTIBILITY TO LOCALIZED CORROSION TO THE PH OF NITRATE BASED NUCLEAR WASTES

    Energy Technology Data Exchange (ETDEWEB)

    BOOMER KD

    2010-01-14

    The Hanford tank reservation contains approximately 50 million gallons of liquid legacy radioactive waste from cold war weapons production, which is stored in 177 underground storage tanks. The tanks will be in use until waste processing operations are completed. The wastes tend to be high pH (over 10) and nitrate based. Under these alkaline conditions carbon steels tend to be passive and undergo relatively slow uniform corrosion. However, the presence of nitrate and other aggressive species, can lead to pitting and stress corrosion cracking. This work is a continuation of previous work that investigated the propensity of steels to suffer pitting and stress corrosion cracking in various waste simulants. The focus of this work is an investigation of the sensitivity of the steels' pitting and stress corrosion cracking susceptibility tosimulant pH. Previous work demonstrated that wastes that are high in aggressive nitrate and low in inhibitory nitrite are susceptible to localized corrosion. However, the previous work involved wastes with pH 12 or higher. The current work involves wastes with lower pH of 10 or 11. It is expected that at these lower pHs that a higher nitrite-to-nitrate ratio will be necessary to ensure tank integrity. This experimental work involved both electrochemical testing, and slow strain rate testing at either the free corrosion potential or under anodic polarization. The results of the current work will be discussed, and compared to work previously presented.

  4. Carbon Segregation of Bearing Steel Concasting Billet

    Institute of Scientific and Technical Information of China (English)

    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.

  5. A study on the hydrogen embrittlement mitigation of carbon and low alloy steel for nuclear power plan piping

    International Nuclear Information System (INIS)

    A new concept in implementing hydrogen embrittlement (HE) mitigation on nuclear piping materials was suggested by using electro-transport treatment. The electro-transport treatment can be applied to reduce HE susceptibility and thus make the material more resistant to hydrogen damage. To demonstrate the validation of the developed method, the effect of hydrogen on the tensile properties of SA-508 Grade 1-A low alloy steel was investigated by slow strain rate test (SSRT). Material characteristics were observed as a function of hydrogen charging condition and electro-transport treatment. In SSRT results, SA-508 low alloy steel was not susceptible to hydrogen embrittlement. However, significant embrittlement was found for a specimen at applied cathodic potentials plus loading condition. When electro-transport treatment was performed, however, the ductility of the specimen was much higher than those of tested in air. These experimental results suggest that electro-transport treatment can be a potential method to mitigate the sensitivity of hydrogen embrittlement and could replace the conventional post-weld heat treatment

  6. Characterization of oxide film layers formed on A106 B carbon steel in simulated secondary coolant conditions of nuclear power plants

    International Nuclear Information System (INIS)

    The water chemistry of the secondary coolant in the majority Nuclear Power Plants is controlled by AVT (All Volatile Treatment) procedure, wherein volatile amines are use to maintain the alkaline pH required for minimizing the corrosion of structural materials which one of them is Carbon Steel. In this procedure: hydrazine, morpholine and ethanolamine are used commonly as conditioning reagents. In this context, experiments were carried out by exposing carbon steel A106 B samples in a simulated secondary coolant in order to study the nature of the oxide films. The tests were performed in a static autoclave at 260 ºC using two media: 1) Hydrazine + morpholine and 2) Hydrazine + ethanolamine during different exposure periods up to ≈1020 h. The composition, surface morphology, X-ray diffraction, a chemical descaling procedure were used- XPS, was also employed, to analyze the films grown during ≈1020 h in both media. The characterization showed that magnetite was the main corrosion product formed in the films grown in the two media. The material weight loss (W) could be fitted by a law of the type W = k tn, up to 1020 h of exposure, resulting in n =0,42, k = 6,24 for films grown in medium 1) and n = 0,39, k =6,08 for films grown in medium 2); where W is in mg/d m2 and t in h. (author)

  7. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Science.gov (United States)

    2010-10-01

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

  8. Plain carbon steel bipolar plates for PEMFC

    Institute of Scientific and Technical Information of China (English)

    WANG Jianli; SUN Juncai; TIAN Rujin; XU Jing

    2006-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Special steels for nuclear power plants

    International Nuclear Information System (INIS)

    Evolution of needs of steels and of relations between users and producers is reviewed in the field of nuclear power stations. Very important components are needed now with specifications concerning corrosion, mechanical properties under irradiation. Performances and fiability of steels are now improved by vacuum degassing, new refining methods giving a better control of purity, additions, homogeneity, transition temperature. Testing methods are improved too. Some examples are given of steels for reactor vessel, primary coolant circuit and different smaller components of reactors

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

    Science.gov (United States)

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

    2015-07-01

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

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

    International Nuclear Information System (INIS)

    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

  13. Electrochemical corrosion studies on a selected carbon steel for application in nuclear waste disposal containers: Influence of chemical species in brines on corrosion

    International Nuclear Information System (INIS)

    In previous corrosion studies, carbon steels were identified as promising materials for the manufacture of long-lived high-level waste containers that could act as an engineered barrier in a rock-salt repository. In this paper, the influence of chemical species, potentially present in salt brines, on the electrochemical corrosion behavior of the preselected fine-grained steel TStE 355 was studied. The steel was examined at 90 C in a disposal relevant NaCl-rich brine containing various species (Br-, I-, Cu2+, Mn2+, S2-, B(OH)4- and Fe3+) at concentrations between 10-5 M/I and 10-1 M/I. (orig.)

  14. Trial manufacturing of titanium-carbon steel composite overpack

    Energy Technology Data Exchange (ETDEWEB)

    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)

  15. Trial manufacturing of titanium-carbon steel composite overpack

    International Nuclear Information System (INIS)

    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)

  16. Development of structural steels for nuclear application

    International Nuclear Information System (INIS)

    To established the bases of nuclear structural material technologies, this study was focused on the localization and improvement of nuclear structural steels, the production of material property data, and technology developments for integrity evaluation. The important test and analysis technologies for material integrity assessment were developed, and the materials properties of the pressure vessel steels were evaluated systematically on the basis of those technologies, they are microstructural characteristics, tensile and indentation deformation properties, impact properties, and static and dynamic fracture toughness, fatigue and corrosion fatigue etc. Irradiation tests in the research reactors were prepared or completed to obtain the mechanical properties of irradiated materials. The improvement of low alloy steel was also attempted through the comparative study on the manufacturing processes, computer assisted alloy and process design, and application of the inter critical heat treatment. On the other hand, type 304 stainless steels for reactor internals were developed and tested successfully. High strength type 316LN stainless steels for reactor internals were developed and the microstructural characteristics, corrosion resistance, mechanical properties at high temperatures, low cycle fatigue property etc. were tested and analyzed in the view point of the effect of nitrogen. Type 347 stainless steels with high corrosion resistance and toughness for pipings and tubes and low-activated Cr-Mn steels were also developed and their basic properties were evaluated. Finally, the martensitic stainless steels for turbine blade were developed and tests. (author). 242 refs., 100 tabs., 304 figs

  17. Development of structural steels for nuclear application

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jun Hwa; Chi, S. H.; Ryu, W. S.; Lee, B. S.; Kim, D. H.; Kim, J. H.; Oh, Y. J.; Byun, T. S.; Yoon, J. H.; Park, D. K.; Oh, J. M.; Cho, H. D.; Kim, H.; Kim, H. D.; Kang, S. S.; Kim, J. W.; Ahn, S. B.

    1997-08-01

    To established the bases of nuclear structural material technologies, this study was focused on the localization and improvement of nuclear structural steels, the production of material property data, and technology developments for integrity evaluation. The important test and analysis technologies for material integrity assessment were developed, and the materials properties of the pressure vessel steels were evaluated systematically on the basis of those technologies, they are microstructural characteristics, tensile and indentation deformation properties, impact properties, and static and dynamic fracture toughness, fatigue and corrosion fatigue etc. Irradiation tests in the research reactors were prepared or completed to obtain the mechanical properties of irradiated materials. The improvement of low alloy steel was also attempted through the comparative study on the manufacturing processes, computer assisted alloy and process design, and application of the inter critical heat treatment. On the other hand, type 304 stainless steels for reactor internals were developed and tested successfully. High strength type 316LN stainless steels for reactor internals were developed and the microstructural characteristics, corrosion resistance, mechanical properties at high temperatures, low cycle fatigue property etc. were tested and analyzed in the view point of the effect of nitrogen. Type 347 stainless steels with high corrosion resistance and toughness for pipings and tubes and low-activated Cr-Mn steels were also developed and their basic properties were evaluated. Finally, the martensitic stainless steels for turbine blade were developed and tests. (author). 242 refs., 100 tabs., 304 figs.

  18. Nuclear process heat for the steel industry

    International Nuclear Information System (INIS)

    There are various possibilities for using nuclear process heat from a high temperature reactor to reduce iron ore, each using different proportions of nuclear energy. The advantages in separating the high temperature reactor with its associated reducing gas producer from any steel complex, include the ability to supply such gas to other consumers additional to the steel industry. The potential for nuclear gas-producing complexes in Western Europe is discussed as is the need for appropriate co-operation in the considerable research that will be needed to bring this new technology about. (orig.)

  19. Welding of high manganese- and carbon steels

    International Nuclear Information System (INIS)

    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

  20. Marine atmospheric corrosion of carbon steels

    OpenAIRE

    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...

  1. Deformation and Recrystallisation in Low Carbon Steels

    OpenAIRE

    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...

  2. Draft guideline of NDI for low carbon stainless steel

    International Nuclear Information System (INIS)

    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)

  3. Corrosion Resistibility of Chemical Inhibitors for Carbon Steels in the Closed Cooling Water System of Nuclear Power Plant

    International Nuclear Information System (INIS)

    In the Nuclear Power Plant (NPP), the Closed Cooling Water (CCW) system provides cooling to both safety-related and non-safety-related heat exchange equipment. In general, chemical treatment is used for minimizing corrosion, controlling microbiological growth, and preventing scale in the CCW system. In the NPP, these inhibitors have included chromate, nitrite, molybdate, hydrazine, and polysilicate. In some domestic NPPs in which nitrite inhibitor program was adapted, during overhaul period, saturation of ion exchange resin caused by corrosion inhibitor which has high conductivity is causative for increase in the radiation exposure and the radioactive waste. To prevent corrosion without any disadvantages, we must accurately evaluate influence of inhibitor in the CCW system. The objective of this study is to evaluate the corrosion behavior of CCW materials with various corrosion inhibitors

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

    International Nuclear Information System (INIS)

    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

  5. Tests Of Protective Coats For Carbon Steel

    Science.gov (United States)

    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.

  6. Corrosion behaviour of carbon steel in the Tournemire clay

    International Nuclear Information System (INIS)

    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)

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

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

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

  8. Cleavage behaviors in nuclear vessel steels

    International Nuclear Information System (INIS)

    Cleavage behaviors of nuclear vessel steels in the transition temperature range are reviewed. Viewpoints are presented to assist understanding of cleavage crack speed, cleavage initiation, cleavage arrest, and the sensitivity of fracture toughness to constraint and temperature. The importance of high local stress elevations by high strain rate is emphasized. This report is designated as HSST Report No. 149

  9. Stainless steel forgings for nuclear chemical plants

    International Nuclear Information System (INIS)

    This Specification covers detailed requirements for the supply of austenitic stainless steel forgings used in radioactive and corrosive areas within the Nuclear Industry. With the exception of 316S51 the materials specified are all suitable for contact with nitric acid, 316S51 being included as suitable for use in contact with sodium and other alkali metals at elevated temperatures. (author)

  10. The kinetics of pitting corrosion of carbon steel

    International Nuclear Information System (INIS)

    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. Microbially induced corrosion of carbon steel in deep groundwater environment

    OpenAIRE

    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...

  12. EIS Response of MIC on Carbon Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Maahn, Ernst

    1998-01-01

    Abstract Microbially influenced corrosion of carbon steel under sulphate reducing (sulphide-producing) bacterial activity (SRB) results in the formation of both ferrous sulphides as well as biofilm on the metal surface. The electrochemical characteristics of the ferrous sulphide/steel interface as...... 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...

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

  16. Integrating Steel Production with Mineral Carbon Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Low carbon manganese-nickel-niobium steel

    International Nuclear Information System (INIS)

    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)

  18. Marine atmospheric corrosion of carbon steels

    International Nuclear Information System (INIS)

    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)

  19. Marine atmospheric corrosion of carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    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)

  20. Nanostructure-based Processes at the Carbonizing Steels

    Directory of Open Access Journals (Sweden)

    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.

  1. Radioactive waste isolation in salt: Peer review of the Office of Nuclear Waste Isolation's draft report on a multifactor test design to investigate uniform corrosion of low-carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Paddock, R.A.; Lerman, A.; Ditmars, J.D.; Macdonald, D.D.; Peerenboom, J.P.; Was, G.S.; Harrison, W.

    1987-01-01

    This report documents Argonne National Laboratory's review of an internal technical memorandum prepared by Battelle Memorial Institute's Office of Nuclear Waste Isolation (ONWI) entitled Multifactor Test Design to Investigate Uniform Corrosion of Low-Carbon Steel in a Nuclear Waste Salt Repository Environment. The several major areas of concern identified by peer review panelists are important to the credibility of the test design proposed in the memorandum and are to adequately addressed there. These areas of concern, along with specific recommendations to improve their treatment, are discussed in detail in Sec. 2 of this report. The twenty recommendations, which were abstracted from those discussions, are presented essentially in the order in which they are introduced in Sec. 2.

  2. Internal friction in martensitic carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Ultrahigh carbon steel for automotive applications

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. Internal friction in martensitic carbon steels

    International Nuclear Information System (INIS)

    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.

  5. Mechanistic Understanding Of Caustic Cracking Of Carbon Steels

    International Nuclear Information System (INIS)

    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

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

    OpenAIRE

    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...

  7. Effect of heat treatment on carbon steel pipe welds

    International Nuclear Information System (INIS)

    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

  8. Friction stir processing on carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Friction stir processing on carbon steel

    International Nuclear Information System (INIS)

    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

  10. 76 FR 15299 - Certain Hot-Rolled Carbon Steel Flat Products From India: Preliminary Rescission of...

    Science.gov (United States)

    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,...

  11. Test Of Protective Coatings On Carbon Steel

    Science.gov (United States)

    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.

  12. Passivation of carbon steel through mercury implantation

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    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)

  14. Microbially influenced corrosion of carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. Corrosion rate of carbon steel in NS tank water

    International Nuclear Information System (INIS)

    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)

  16. Thermoplastic liners for carbon steel pipelines

    Energy Technology Data Exchange (ETDEWEB)

    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)

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

    International Nuclear Information System (INIS)

    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

  18. Basic studies on carbon steel decontamination

    International Nuclear Information System (INIS)

    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

  19. Strength enhancement possibilities of low carbon steels

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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...

    Science.gov (United States)

    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. Nondestructive inspection technologies for low-carbon stainless steel

    International Nuclear Information System (INIS)

    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)

  4. Marine atmospheric corrosion of carbon steels

    Directory of Open Access Journals (Sweden)

    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

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

    Institute of Scientific and Technical Information of China (English)

    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.

  6. Assessment of wall-thinning in carbon steel pipe by using laser-generated guided wave

    Energy Technology Data Exchange (ETDEWEB)

    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

  7. Tests Of Materials For Repair Coating Of Carbon Steel

    Science.gov (United States)

    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.

  8. Warm Deformation Microstructure of a Plain Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    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

  9. Automatic orbital TIG-welding of small bore austenitic stainless steel tubes for nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

    Traditionally, manual welding techniques have been employed for shop and site fabrication of small bore austenitic stainless steel tubes in the nuclear fuel reprocessing plant of British Nuclear Fuels Limited (BNFL). This Paper describes an evaluation programme carried out to develop welding procedures for both 18Cr-13Ni-1Nb and 18Cr-10Ni low carbon stainless steel small bore tubing, the type of equipment used, and the modifications required for application to shop and site environments. (author)

  10. Investigation of boron segregation in low carbon steel

    OpenAIRE

    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 ...

  11. 76 FR 2344 - Certain Hot-Rolled Carbon Steel Flat Products From India: Notice of Preliminary Results of...

    Science.gov (United States)

    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...

  12. 76 FR 48143 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Preliminary...

    Science.gov (United States)

    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...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

  15. Heat treatments in a conventional steel to reproduce the microstructure of a nuclear grade steel

    International Nuclear Information System (INIS)

    The ferritic steels used in the manufacture of pressurized vessels of Boiling Water Reactors (BWR) suffer degradation in their mechanical properties due to damage caused by the neutron fluxes of high energy bigger to a Mega electron volt (E> 1 MeV) generated in the reactor core. The materials with which the pressurized vessels of nuclear reactors cooled by light water are built correspond to low alloy ferritic steels. The effect of neutron irradiation on these steels is manifested as an increase in hardness, mechanical strength, with the consequent decrease in ductility, fracture toughness and an increase in temperature of ductile-brittle transition. The life of a BWR is 40 years, its design must be considered sufficient margin of safety because pressure forces experienced during operation, maintenance and testing of postulated accident conditions. It is necessary that under these conditions the vessel to behave ductile and likely to propagate a fracture is minimized. The vessels of light water nuclear reactors have a bainite microstructure. Specifically, the reactor vessels of the nuclear power plant of Laguna Verde (Veracruz, Mexico) are made of a steel Astm A-533, Grade B Class 1. At present they are carrying out some welding tests for the construction of a model of a BWR, however, to use nuclear grade steel such as Astm A-533 to carry out some of the welding tests, is very expensive; perform these in a conventional material provides basic information. Although the microstructure present in the conventional material does not correspond exactly to the degree of nuclear material, it can take of reference. Therefore, it is proposed to conduct a pilot study to establish the thermal treatment that reproduces the microstructure of nuclear grade steel, in conventional steel. The resulting properties of the conventional steel samples will be compared to a JRQ steel, that is a steel Astm A-533, Grade B Class 1, provided by IAEA. (Author)

  16. Trial manufacturing of copper-carbon steel composite overpack

    International Nuclear Information System (INIS)

    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)

  17. The kinetics of pitting corrosion of carbon steel

    International Nuclear Information System (INIS)

    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)

  18. Development of a duplex cast stainless steel for nuclear purposes

    International Nuclear Information System (INIS)

    The starting material was a Finnish austenitic-ferritic stainless steel belonging to the family of widely used CF 308 M cast steels. This original HKS steel failed in the Strauss tests, which are of primary importance for materials used in nuclear power piles. Development work on lowering the ferrite and interstitial impurity contents influenced the properties of the steel so much that it no longer failed the Strauss test nor showed any brittleness when tested after irradiation treatment. Welded samples also showed no brittleness, provided the welding was carried out using correct filler materials and suitable heat input. (author)

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

    International Nuclear Information System (INIS)

    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

  20. Current steel forgings and their properties for steam generator of nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Tomoharu; Murai, Etsuo; Sato, Ikuo [Japan Steel Works Ltd., Muroran, Hokkaido (Japan). Muroran Plant; Suzuki, Kimiaki; Kusuhashi, Mikio; Tsukada, Hisashi [Japan Steel Works Ltd., Tokyo (Japan)

    2001-06-01

    On the steel forging (SF) elements for steam generator (SG) of the pressurized water type light water reactor (PWR), from a viewpoint of upgrading in their improvements of design and materials, here were described on three materials such as integrated steel forgings, high strength steel forgings, and vacuum carbon deoxidisation (VCD) steel forgings. On production of SG, by using the integrated SF, not only structural soundness of SG is upgraded, but also inspections containing inspections under production and usage become easier, to bring minimization of maintenance inspection and reduction of exposure under operation. And, in order to reduce weight of SG and upgrade seismic resistance, SA508, a Cl.3a high strength SF (620 MPa class in tensile strength) is used for some nuclear plants. Here were introduced material properties of this SF and described its chemical components and heat treatment condition. And, as a method to reduce macro- and micro-segregation of materials and to upgrade homogeneity of material property, a method combined deoxidisation of steel due to carbon monoxide reaction with crystal grain minimization due to addition of aluminum was investigated. In addition, properties of a low Si-SA508 Cl.3 steel using this method was compared with that of usual SA508 Cl.3 steel. (G.K.)

  1. Current steel forgings and their properties for steam generator of nuclear power plant

    International Nuclear Information System (INIS)

    On the steel forging (SF) elements for steam generator (SG) of the pressurized water type light water reactor (PWR), from a viewpoint of upgrading in their improvements of design and materials, here were described on three materials such as integrated steel forgings, high strength steel forgings, and vacuum carbon deoxidisation (VCD) steel forgings. On production of SG, by using the integrated SF, not only structural soundness of SG is upgraded, but also inspections containing inspections under production and usage become easier, to bring minimization of maintenance inspection and reduction of exposure under operation. And, in order to reduce weight of SG and upgrade seismic resistance, SA508, a Cl.3a high strength SF (620 MPa class in tensile strength) is used for some nuclear plants. Here were introduced material properties of this SF and described its chemical components and heat treatment condition. And, as a method to reduce macro- and micro-segregation of materials and to upgrade homogeneity of material property, a method combined deoxidisation of steel due to carbon monoxide reaction with crystal grain minimization due to addition of aluminum was investigated. In addition, properties of a low Si-SA508 Cl.3 steel using this method was compared with that of usual SA508 Cl.3 steel. (G.K.)

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

    International Nuclear Information System (INIS)

    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

  3. Effects of fatigue in the elastic regime on the mechanical properties of nuclear pressure vessel steels

    International Nuclear Information System (INIS)

    The mechanical properties behavior of one low carbon steel, SAE 1018, and two nuclear pressure vessel steels, A533B Class I and A533B Class II, all with similar compositions, is examined after fatigue in the elastic regime. Cyclic stresses were applied at stress amplitudes of +.207 MPa (+.30 ksi), the design limit for the pressure vessel steels, and well below the upper and lower yield strengths for all of the steels. The fatigue cycling was carried out at room temperature in all cases, and at 3000C for the pressure vessel steels, to 104 and 106 cycles. Specimens which had undergone the fatigue treatment were then tensile and notch tensile tested to determine mechanical properties changes. In addition, electron microscopy techniques were used to characterize the microstructure developed during fatigue. The results show that mechanical properties are affected by elastic fatigue. In general, the materials are more ductile after fatigue than in the as-received condition. The microstructural examination indicates that this change is due to the dislocation substructure which is developed during fatigue. These findings may have a profound impact on predicting behavior of steels in nuclear pressure vessels where alternating stresses are present during operation. To date, the tendency for pressure vessel steel embrittlement under irradiation has been determined from unstressed specimens

  4. Development of stainless steels for nuclear power plant - Advanced nuclear materials development -

    International Nuclear Information System (INIS)

    This report reviews the status of R and D and the material specifications of nuclear components in order to develop the stainless steels for nuclear applications, and the technology of computer-assisted alloy design is developed to establish the thermodynamic data of Fe-Cr-Ni-Mo-Si-C-N system which is the basic stainless steel systems. High strength and corrosion resistant stainless steels, 316LN and super clean 347, are developed, and the manufacturing processes and heat treatment conditions are determined. In addition, a martensitic steel is produced as a model alloy for turbine blade, and characterized. The material properties showed a good performance for nuclear applications. (Author)

  5. Carbon Cycling with Nuclear Power

    Science.gov (United States)

    Lackner, Klaus S.

    2011-11-01

    Liquid hydrocarbon fuels like gasoline, diesel or jet fuel are the most efficient ways of delivering energy to the transportation sector, in particular cars, ships and airplanes. Unfortunately, their use nearly unavoidably leads to the emission of carbon dioxide into the atmosphere. Unless an equivalent amount is removed from the air, the carbon dioxide will accumulate and significantly contribute to the man-made greenhouse effect. If fuels are made from biomass, the capture of carbon dioxide is a natural part of the cycle. Here, we discuss technical options for capturing carbon dioxide at much faster rates. We outline the basic concepts, discuss how such capture technologies could be made affordable and show how they could be integrated into a larger system approach. In the short term, the likely source of the hydrocarbon fuels is oil or gas; in the longer term, technologies that can provide energy to remove oxygen from carbon dioxide and water molecules and combine the remaining components into liquid fuels make it possible to recycle carbon between fuels and carbon dioxide in an entirely abiotic process. Here we focus on renewable and nuclear energy options for producing liquid fuels and show how air capture combined with fuel synthesis could be more economic than a transition to electric cars or hydrogen-fueled cars.

  6. Microstructural characterisation of carbon implanted austenitic stainless steel

    International Nuclear Information System (INIS)

    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

  7. Microstructural characterisation of carbon implanted austenitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

  9. Slow strain rate testing of carbon steel in solutions with high nitrate concentrations

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

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

    Institute of Scientific and Technical Information of China (English)

    Fan Li; Haibo Huang

    2006-01-01

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

  12. 48 CFR 252.225-7030 - Restriction on Acquisition of Carbon, Alloy, and Armor Steel Plate.

    Science.gov (United States)

    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...

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

    Directory of Open Access Journals (Sweden)

    Warzecha M.

    2016-03-01

    Full Text Available In the present paper, secondary metallurgical treatment in ladle furnace during smelting the high carbon steel and steel with improved ductility for cold-deforming, under industrial conditions were analyzed.

  14. 75 FR 65453 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Flat Products From Brazil: Notice of...

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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.

  16. 78 FR 42039 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Preliminary...

    Science.gov (United States)

    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)....

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Development and processing of low carbon bainitic steels

    OpenAIRE

    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...

  19. MICROBIAL CORROSION OF MILD AND MEDIUM CARBON STEELS

    OpenAIRE

    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)....

  20. The anaerobic corrosion of carbon steel in concrete

    International Nuclear Information System (INIS)

    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

  1. ESTIMATION OF IRREVERSIBLE DAMAGEABILITY AT FATIGUE OF CARBON STEEL

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    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.

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

    KAUST Repository

    Itty, Pierre-Adrien

    2014-06-01

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

  4. Extreme value statistical analysis for wall thickness of elbow part of carbon steel tube

    International Nuclear Information System (INIS)

    Relating to the resent accident occurred in Mihama Nuclear Power Plant, the estimation method of the minimum value of the wall thickness of carbon steel pipes is concerned, because the minimum wall thickness value is required to decide the exact replacement time of the pipe. Currently in the nuclear power plants, the wall thickness is measured by the ultra-sonic method and the minimum value of the wall thickness decided from the smallest value among 8 values which are obtained at 8 points set around the circumference of the pipes. The minimum value thus determined, however, is not true minimum value and the exact minimum value could be determined by the Extreme Value Statistical Analysis applying for 8 measurement values. This study aims to analyze the field data on the elbow part of carbon steel pipes in order to demonstrate the usefulness of the Extreme Value Statistical Analysis. (author)

  5. MICROBIAL CORROSION OF MILD AND MEDIUM CARBON STEELS

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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)

  7. Austenite Recrystallization and Controlled Rolling of Low Carbon Steels

    Institute of Scientific and Technical Information of China (English)

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

    2006-01-01

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

  8. Initial Atmospheric Corrosion of Carbon Steel in Industrial Environment

    Science.gov (United States)

    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.

  9. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    DEFF Research Database (Denmark)

    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...

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

    Institute of Scientific and Technical Information of China (English)

    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.

  11. Wear modelling of diamond-like carbon coatings against steel in deionised water

    OpenAIRE

    Sutton, Daniel Christopher

    2014-01-01

    Diamond-Like Carbon (DLC) coatings are thin protective surface coatings used to reduce friction and minimise wear in a wide range of applications. The focus of this work is the use of DLC coatings within Rolls-Royce’s pressurised water reactors. A strong understanding of material behaviour in this environment is compulsory due to the stringent safety requirements of the nuclear industry. Wear testing of a range of commercial DLC coatings against steel in water, and the dependence of the tribo...

  12. The electrochemistry of carbon steel in simulated concrete pore water in boom clay repository environments

    OpenAIRE

    Rosas-Camacho O.; Azizi O.; Lee S.K.; Saleh A; Macdonald D.D.; Al-Marzooqi A.; Taylor M

    2011-01-01

    The prediction of corrosion damage of canisters to experimentally inaccessible times is vitally important in assessing various concepts for the disposal of High Level Nuclear Waste. Such prediction can only be made using deterministic models, whose predictions are constrained by the time-invariant natural laws. In this paper, we describe the measurement of experimental electrochemical data that will allow the prediction of damage to the carbon steel overpack of the super container in Belgium’...

  13. 76 FR 78882 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Affirmative Preliminary Determination of...

    Science.gov (United States)

    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...

  14. Electrochemical noise from corroding carbon steel and aluminium

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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.

  16. Residual stress measurements in carbon steel

    Science.gov (United States)

    Heyman, J. S.; Min, N.

    1986-01-01

    External dc magnetic field-induced changes in natural velocity of Rayleigh surface waves were measured in steel specimens under various stress conditions. The low field slopes of curves representing the fractional changes of natural velocity were proved to provide correct stress information in steels with different metallurgical properties. The slopes of curves under uniaxial compression, exceeding about one third of the yield stress, fell below zero in all the specimens when magnetized along the stress axis. The slopes under tension varied among different steels but remained positive in any circumstances. The stress effect was observed for both applied and residual stress. A physical interpretation of these results is given based on the stress-induced domain structure changes and the delta epsilon effect. Most importantly, it is found that the influence of detailed metallurgical properties cause only secondary effects on the obtained stress information.

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    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)

  20. 76 FR 45509 - Final Results of Antidumping Duty Changed Circumstances Review: Carbon and Certain Alloy Steel...

    Science.gov (United States)

    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...

  1. 78 FR 34340 - Welded Carbon Steel Standard Pipe and Tube Products From Turkey: Preliminary Results of...

    Science.gov (United States)

    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)...

  2. Accelerated development of advanced steels for nuclear applications

    International Nuclear Information System (INIS)

    Significant progress has been achieved in the operational performance and radiation resistance of ferritic-martensitic steels during the past few decades. Conventional high temperature steels, such as HT-9 and 2 1/4 Cr-1Mo have evolved into super Oxide Dispersion Strengthened (ODS) steels through successive optimization to meet strict performance and radiation-resistance constraints. Such evolution was possible through a combination of experimentation, modeling and empirical information. Further development and optimization of structural steels in nuclear applications will require full utilization of the available array of sophisticated experimental techniques and multiscale computational modeling, in addition to empirical data. We present here a systematic approach to the process of optimum steel development, by linking material fabrication to thermo-mechanical properties through a physical understanding of microstructure evolution. The optimization process is based on the application of design constraints (e.g. low activation, low DBTT, low swelling, creep resistance, and weldability) to describe the required microstructures, which in turn, can be controlled through material processing techniques. Prospects for future design of optimum structural steels in nuclear applications by utilization of the hierarchy of multiscale experimental and computational strategies will be described. (author)

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

    International Nuclear Information System (INIS)

    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.)

  4. Atmospheric corrosion of carbon steel in the prairie regions

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Investigation of boron segregation in low carbon steel

    Directory of Open Access Journals (Sweden)

    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.

  6. Oxidation of ultra low carbon and silicon bearing steels

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-06-15

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

  7. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    DEFF Research Database (Denmark)

    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...

  8. Friction and wear characteristics of carbon steels in vacuum

    Science.gov (United States)

    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.

  9. Carbon distribution in bainitic steel subjected to deformation

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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.

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

    DEFF Research Database (Denmark)

    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....

  12. Carbon distribution in bainitic steel subjected to deformation

    International Nuclear Information System (INIS)

    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

  13. Vanadium Effect on a Medium Carbon Forging Steel

    Directory of Open Access Journals (Sweden)

    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.

  14. Laser-ultrasonic absorption measurements in low carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    Science.gov (United States)

    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.

  16. 75 FR 64254 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products From Brazil; Final Results of...

    Science.gov (United States)

    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)...

  17. 75 FR 19369 - Certain Hot-Rolled Flat-Rolled Carbon Quality Steel Products from Brazil: Preliminary Results of...

    Science.gov (United States)

    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...

  18. 76 FR 66901 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Final...

    Science.gov (United States)

    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...

  19. 75 FR 4779 - Certain Cut-to-Length Carbon-Quality Steel Plate Products From Italy: Preliminary Results of...

    Science.gov (United States)

    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,...

  20. 77 FR 32513 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From the Russian Federation; Preliminary...

    Science.gov (United States)

    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,...

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

    International Nuclear Information System (INIS)

    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)

  2. Variability of mechanical properties of nuclear pressure vessel steels

    International Nuclear Information System (INIS)

    Causes of variability of mechanical properties nuclear pressure vessel steels are reviewed and discussed. The effects of product shape and size, processing history and heat treatment are investigated. Some quantitative informations are given on the scatter of mechanical properties of typical pressure vessel components. The necessity of using recommended or standardized properties for comparing mechanical properties before and after irradiation in pin pointed. (orig.)

  3. Elastic Sag Property of Low Carbon Martensite Spring Steel

    Institute of Scientific and Technical Information of China (English)

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

    2004-01-01

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

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

    Czech Academy of Sciences Publication Activity Database

    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/

  5. Intragranular ferrite in inoculated low-carbon steels

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  7. Weldability of Low Carbon Transformation Induced Plasticity Steel

    Institute of Scientific and Technical Information of China (English)

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

    2008-01-01

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

  8. Detection of wall thinning of carbon steel pipe covered with insulation using Pulsed Eddy Current technique

    International Nuclear Information System (INIS)

    The test sample is a ferromagnetic carbon steel pipe having different thickness, covered with a 10 cm plastic insulation laminated by 0.4 mm Al plate to simulate the pipelines in NPPs. The PEC Probe used for the wall thinning detection consists of an excitation coil and a Hall sensor. The excitation coils in the probe is driven by a rectangular bipolar current pulse and the Hall-sensor will detects the resultant field. The Hall sensor output is considered as PEC signal. Results shows that the PEC system can detect wall thinning in an insulated pipeline of the NPPs. Local wall thinning in pipelines affects the structural integrity of industries like nuclear power plants (NPPs). In the present study a pulsed eddy current (PEC) technology to detect the wall thing of carbon steel pipe covered with insulation is developed

  9. The compatibility of chromium-aluminium steels with high pressure carbon dioxid at intermediate- temperatures

    International Nuclear Information System (INIS)

    With a view to their use in the exchangers of nuclear reactors of the graphite-gas or heavy water-gas types, the behaviour of chromium-aluminium steels containing up to 7 per cent chromium and 1.5 per cent aluminium has been studied in the presence of high-pressure carbon dioxide at temperatures of between 400 and 700 deg. C. The two most interesting grades of steel (2 per cent Cr - 0.35 per cent Al - 0.35 per cent Mo and 7 per cent Cr - 1.5 per cent Al - 0.6 per cent Si) are still compatible with carbon dioxide up to 550 and 600 deg. C respectively. A hot dip aluminised coating considerably increases resistance to oxidation of the first grade and should make possible its use up to temperatures of at least 600 deg. C. (authors)

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

    Science.gov (United States)

    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.

  11. Anticorrosive Influence of Acetobacter aceti Biofilms on Carbon Steel

    Science.gov (United States)

    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.

  12. Friction stir welding of nuclear grade dissimilar steels

    International Nuclear Information System (INIS)

    SA508 Class 3 low alloy Mn-Mo-Ni steel is a reactor pressure vessel material, widely used in the world. In the reactors, fuel is arranged in a row of fuel pins and linked with portable control rods. The fuel is in a SA 508 steel container through which water is pumped at a high pressure into reactor vessel via cold lag pipeline. The water to act as both a coolant and a moderator. After absorbing the heat from the core of reactor, pressurised water is passed on a steam generator, via hot lag pipeline. Both hot lag and cold lag pipe lines are made of SS 304 LN steel. These both steels are generally welded by common arc welding process which may causes carbon migration, thermal stress, metallurgical deterioration, residual stress, etc. Friction stir welding (FSW) is a new solid state welding process develop by TWI in 1991 (UK) which generally removed all type of solidification problem. In this study Friction stir welding is performed for welding of SA 508 and SS 304 LN dissimilar steels. Defect free sound weld were produced having strength more than the SS 304 LN steel and toughness more than the SA 508. Microstructure and hardness represents the formation of martensite formation in weld nugget. (author)

  13. The effect of chloride ion on the iron elution from carbon steel in high temperature water

    International Nuclear Information System (INIS)

    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

  14. The use of nuclear heat in the steel industry

    International Nuclear Information System (INIS)

    It is possible, but not easy, to use nuclear energy for steelmaking: low temperature level, and difficulty to get a continuous energy supply, are the main limiting factors. Practically, the nuclear reactor and the steel making units will not be coupled. Among the various possible systems, the most practical one for the near future consists in using nuclear heat to produce hydrogen (using natural gas or oil products as a feedstock) and electric power. Hydrogen is used to reduce iron ore in units such as Midrex, Hyl, Armco or Purofer. Steel is produced from this reduced material in electric arc furnaces. Industrial development will be slow, since economical conditions are presently pretty far from making such a process economically competitive

  15. Effects of tempering on internal friction of carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Effects of tempering on internal friction of carbon steels

    International Nuclear Information System (INIS)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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].

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Pyrolytic carbon-caoted nuclear fuel

    International Nuclear Information System (INIS)

    An improved nuclear fuel kernel having at least one pyrolytic carbon coating and a silicon carbon layer is provided in which extensive interaction of fission product lanthanides with the silicon carbon layer is avoided by providing sufficient UO2 to maintain the lanthanides as oxides during in-reactor use of said fuel

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

    Science.gov (United States)

    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...

    Science.gov (United States)

    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...

    Science.gov (United States)

    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. Continuous Cooling Transformations in Nuclear Pressure Vessel Steels

    Science.gov (United States)

    Pous-Romero, Hector; Bhadeshia, Harry K. D. H.

    2014-10-01

    A class of low-alloy steels often referred to as SA508 represent key materials for the manufacture of nuclear reactor pressure vessels. The alloys have good properties, but the scatter in properties is of prime interest in safe design. Such scatter can arise from microstructural variations but most studies conclude that large components made from such steels are, following heat treatment, fully bainitic. In the present work, we demonstrate with the help of a variety of experimental techniques that the microstructures of three SA508 Gr.3 alloys are far from homogeneous when considered in the context of the cooling rates encountered in practice. In particular, allotriomorphic ferrite that is expected to lead to a deterioration in toughness, is found in the microstructure for realistic combinations of austenite grain size and the cooling rate combination. Parameters are established to identify the domains in which SA508 Gr.3 steels transform only into the fine bainitic microstructures.

  5. The high efficiency steel filters for nuclear air cleaning

    International Nuclear Information System (INIS)

    We have, in cooperation with industry, developed high-efficiency filters made from sintered stainless-steel fibers for use in several air-cleaning applications in the nuclear industry. These filters were developed to overcome the failure modes in present high-efficiency particulate air (HEPA) filters. HEPA filters are made from glass paper and glue, and they may fail when they get hot or wet and when they are overpressured. In developing our steel filters, we first evaluated the commercially available stainless-steel filter media made from sintered powder and sintered fiber. The sintered-fiber media performed much better than sintered-powder media, and the best media had the smallest fiber diameter. Using the best media, we then built prototype filters for venting compressed gases and evaluated them in our automated filter tester. 12 refs., 20 figs

  6. High efficiency steel filters for nuclear air cleaning

    International Nuclear Information System (INIS)

    The authors have, in cooperation with industry, developed high-efficiency filters made from sintered stainless-steel fibers for use in several air-cleaning applications in the nuclear industry. These filters were developed to overcome the failure modes in present high-efficiently particulate air (HEPA) filters. HEPA filters are made from glass paper and glue, and they may fail when they get hot or wet and when they are overpressured. In developing steel filters, they first evaluated the commercially available stainless-steel filter media made from sintered powder and sintered fiber. The sintered-fiber media performed much better than sintered-powder media, and the best media had the smallest fiber diameter. Using the best media, prototype filters were then built for venting compressed gases and evaluated in their automated filter tester

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Science.gov (United States)

    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

  9. Corrosion Behavior of Medium Carbon Steel in Simulated Concentrated Yucca Mountain Waters

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, A; Chandra, D; Rebak, R B

    2004-04-09

    Medium carbon steel (MCS) is the candidate material for rock bolts to reinforce the borehole liners and emplacement drifts of the proposed Yucca Mountain (YM) high-level nuclear waste repository. Corrosion performance of this structural steel -AISI 1040- was investigated by techniques such as linear polarization, electrochemical impedance spectroscopy (EIS), and laboratory immersion tests in lab simulated concentrated YM ground waters. Corrosion rates of the steel were determined for the temperatures in the range from 25 C to 85 C, for the ionic concentrations of 1 time (1x), 10 times (10x), and hundred times (100x) ground waters. The MCS corroded uniformly at the penetration rates of 35-200 {micro}m/year in the de-aerated YM waters, and 200-1000 {micro}m/year in the aerated waters. Increasing temperatures in the de-aerated waters increased the corrosion rates of the steel. However, increasing ionic concentrations influenced the corrosion rates only slightly. In the aerated 1x and 10x waters, increasing temperatures increased the rates of MCS significantly. Inhibitive precipitates, which formed in the aerated 100x waters at higher temperatures (65 C and up) decreased the corrosion rates to the values that obtained for the de-aerated YM aqueous environments. The steel suffered pitting corrosion in the both de-aerated and aerated hot YM environments after anodic polarization.

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

    Directory of Open Access Journals (Sweden)

    Lou Yanchun

    2010-11-01

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

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

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

    OpenAIRE

    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...

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

    OpenAIRE

    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...

  15. Fretting damage of high carbon chromium bearing steel

    OpenAIRE

    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 ...

  16. Ignition properties of nuclear grade activated carbons

    International Nuclear Information System (INIS)

    The ignition property of new activated carbons used in air cleaning systems of nuclear facilities has been evaluated in the past, however very little information has been generated on the behavior of aged, weathered carbons which have been exposed to normal nuclear facility environment. Additionally the standard procedure for evaluation of ignition temperature of carbon is performed under very different conditions than those used in the design of nuclear air cleaning systems. Data were generated evaluating the ageing of activated carbons and comparing their CH3131I removal histories to their ignition temperatures. A series of tests were performed on samples from one nuclear power reactor versus use time, a second series evaluated samples from several plants showing the variability of atmospheric effects. The ignition temperatures were evaluated simulating the conditions existing in nuclear air cleaning systems, such as velocity, bed depth, etc., to eliminate potential confusion resulting from artifically set current standard conditions

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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

  20. 78 FR 64473 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Final No...

    Science.gov (United States)

    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)...

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

    International Nuclear Information System (INIS)

    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

  2. Biaxial dynamic testing of nuclear containment steel

    International Nuclear Information System (INIS)

    A test program has been initiated at the laboratories of the European Union Joint Research Centre of Ispra to investigate combined effects of high strain rates and biaxial stresses. The purpose is to assess the material behavior up to rupture in the special conditions which are produced during an explosion inside a nuclear metal containment. In the paper the main features of the campaign are discussed. (author). 19 refs., 4 figs

  3. Low cycle fatigue behaviour of ODS steels for nuclear application

    Czech Academy of Sciences Publication Activity Database

    Kuběna, Ivo; Kruml, Tomáš; Fournier, B.; Polák, Jaroslav

    2011-01-01

    Roč. 465, - (2011), s. 556-559. ISSN 1013-9826 R&D Projects: GA ČR GA106/09/1954; GA ČR GA101/09/0867 Institutional research plan: CEZ:AV0Z20410507 Keywords : Generation IV nuclear reactors * fusion energy * ODS steels * low cycle fatigue * cyclic softening Subject RIV: JL - Materials Fatigue, Friction Mechanics

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

    OpenAIRE

    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...

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

    International Nuclear Information System (INIS)

    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.

  6. Nuclear energy significantly reduces carbon dioxide emissions

    International Nuclear Information System (INIS)

    This article is devoted to nuclear energy, to its acceptability, compatibility and sustainability. Nuclear energy is non-dispensable part of energy sources with vast innovation potential. The safety of nuclear energy, radioactive waste deposition, and prevention of risk from misuse of nuclear material have to be very seriously adjudged and solved. Nuclear energy is one of the ways how to decrease the contamination of atmosphere with carbon dioxide and it solves partially also the problem of global increase of temperature and climate changes. Given are the main factors responsible for the renaissance of nuclear energy. (author)

  7. 75 FR 64700 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Preliminary Results of...

    Science.gov (United States)

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  9. 76 FR 16607 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Partial Rescission of Antidumping...

    Science.gov (United States)

    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...

  10. 75 FR 8650 - Carbon and Certain Alloy Steel Wire Rod from Trinidad and Tobago; Final Results of Antidumping...

    Science.gov (United States)

    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...

  11. 77 FR 13545 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Final Results of Antidumping Duty...

    Science.gov (United States)

    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...

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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.)

  14. The electrochemistry of carbon steel in simulated concrete pore water in boom clay repository environments

    Directory of Open Access Journals (Sweden)

    Rosas-Camacho O.

    2011-04-01

    Full Text Available The prediction of corrosion damage of canisters to experimentally inaccessible times is vitally important in assessing various concepts for the disposal of High Level Nuclear Waste. Such prediction can only be made using deterministic models, whose predictions are constrained by the time-invariant natural laws. In this paper, we describe the measurement of experimental electrochemical data that will allow the prediction of damage to the carbon steel overpack of the super container in Belgium’s proposed Boom Clay repository by using the Point Defect Model (PDM. PDM parameter values are obtained by optimizing the model on experimental, wide-band electrochemical impedance spectroscopy data.

  15. The electrochemistry of carbon steel in simulated concrete pore water in boom clay repository environments

    Science.gov (United States)

    MacDonald, D. D.; Saleh, A.; Lee, S. K.; Azizi, O.; Rosas-Camacho, O.; Al-Marzooqi, A.; Taylor, M.

    2011-04-01

    The prediction of corrosion damage of canisters to experimentally inaccessible times is vitally important in assessing various concepts for the disposal of High Level Nuclear Waste. Such prediction can only be made using deterministic models, whose predictions are constrained by the time-invariant natural laws. In this paper, we describe the measurement of experimental electrochemical data that will allow the prediction of damage to the carbon steel overpack of the super container in Belgium's proposed Boom Clay repository by using the Point Defect Model (PDM). PDM parameter values are obtained by optimizing the model on experimental, wide-band electrochemical impedance spectroscopy data.

  16. Evaluation of the Microbiologically Influenced Corrosion in a carbon steel making use of electrochemical techniques

    International Nuclear Information System (INIS)

    The Microbiologically Influenced Corrosion (MIC) has been identified as a problem of the nuclear plants systems in the last years. The electrochemical behavior of metal coupons of carbon steel submitted to the action of sulfate reducing bacteria (SRB) was evaluated, making use of the electrochemical techniques of direct current as well as electrochemical noise. The generated results show a little variation in the corrosion velocities which obtained by Tafel extrapolation and resistance to the linear polarization, whereas the electrochemical noise technique presented important differences as regards the registered behavior in environment with and without microorganisms. (Author)

  17. Steel for primary circuit components of nuclear energy generation plants

    International Nuclear Information System (INIS)

    Alloyed ferritic, convertable steels as well as austenite steels are dealt with in this leaflet, which come into consideration for components in the primary circuit of nuclear energy production plants, particularly for reactor pressure vessels. General data on technical details and requirements, tests, heat deformation, heat treatment and measures to be considered, are followed by data in tabular form on chemical composition, proven mechanical properties at room temperature, proven minimum value of the yield points at higher temperatures, reference data for the E modulus, physical properties, hot working and thermal treatment for the steels: 20 MnMoNi 5 5 (1.6310), 22 NiMoCr 3 7(1.6751), 12 MnNiMo 5 5 (1.6343), 12 MnNiMoV 5 4 (1.6342), 8 CrMoNiNb 9 10(1.6770), 20 NiMoV 14 5 (1.6348) 20 NiCrMo 14 6 (1.6742), 20 NiCrMoV 14 6 (1.6950), X 6 CrNiMo 17 13 (1.4919), X 6 CrNi 18 11 (1.4948). A table of the long-term behaviour of the steels 1.4919, 1.4948 and 1.6770 can be found in the appendix, as well as a review of the steels used in reactor building and non-ferritic metal materials, and a compilation of literature on the behaviour of steels after this materials leaflet under neutron irradiation. (orig./IHOE)

  18. Study of carbon steel corrosion layer by X-ray diffraction and absorption methods

    Energy Technology Data Exchange (ETDEWEB)

    Malinovschi, V. [University of Pitesti, Research Center for Advanced Materials, Targul din Vale Street, No.1, 110040 Pitesti, Arges (Romania)]. E-mail: malinov@electra.upit.ro; Ducu, C. [University of Pitesti, Research Center for Advanced Materials, Targul din Vale Street, No.1, 110040 Pitesti, Arges (Romania); Aldea, N. [National Institutes for Research and Development for Isotopic and Molecular Technologies, P.O. Box 700, 3400 Cluj-Napoca (Romania); Fulger, M. [Institutes for Nuclear Research, P.O. Box 0402, 0300 Pitesti (Romania)

    2006-06-30

    To predict the behavior of structural metallic materials into the CANDU nuclear reactor, the oxide films on the surface were growth in a controlled manner using an autoclave simulating the environment specific to the nuclear reactor. In order to establish the structural changes of the oxide films, the X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and extended X-ray absorption fine structure spectroscopy (EXAFS) analysis were used. Analysis performed showed differences in morphology of the oxide films from carbon steel samples exposed under different conditions corresponding to primary and secondary circuits in CANDU nuclear reactor. The oxide phases were identified and the thicknesses of the films were calculated. The agreement between results obtained by these methods was discussed according to the microstructure of the samples.

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

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    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.

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

    International Nuclear Information System (INIS)

    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

  3. Characterization of Bainitic Microstrucutres in Low Carbon Hsla Steels

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

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

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

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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

  9. INFLUENCE OF ELECTRIC SPARK ON HARDNESS OF CARBON STEEL

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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...

  12. Evaluation of Flow Accelerated Corrosion of Carbon Steel with Rotating Cylinder

    International Nuclear Information System (INIS)

    Flow accelerated corrosion (FAC) of the carbon steel piping in nuclear power plants (NPPs) has been major issue in nuclear industry. Rotating cylinder FAC test facility was designed and fabricated and then performance of the facility was evaluated. The facility is very simple in design and economic in fabrication and can be used in material and chemistry screening test. The facility is equipped with on line monitoring of pH, conductivity, dissolved oxygen(DO), and temperature. Fluid velocity is controlled with rotating speed of the cylinder with a test specimen. FAC test of SA106 Gr. B carbon steel under 4 m/s flow velocity was performed with the rotating cylinder at DO concentration of less than 1 ppb and of 1.3 ppm. Also a corrosion test of the carbon steel at static condition, that is at zero fluid velocity, of test specimen and solution was performed at pH from 8 to 10 for comparison with the FAC data. For corrosion test in static condition, the amount of non adherent corrosion product was almost constant at pH ranging from 8 to 10. But adherent corrosion product decreased with increasing pH. This trend is consistent with decrease of Fe solubility with an increase in pH. For FAC test with rotating cylinder FAC test facility, the amount of non adherent corrosion product was also almost same for both DO concentrations. The rotating cylinder FAC test facility will be further improved by redesigning rotating cylinder and FAC specimen geometry for future work

  13. Friction stir processing on high carbon steel U12

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Friction stir processing on high carbon steel U12

    International Nuclear Information System (INIS)

    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

  17. Hybrid Friction Stir Welding of High-carbon Steel

    Institute of Scientific and Technical Information of China (English)

    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.

  18. Electrochemical emission and impedance spectroscopies of passive iron and carbon steel

    Science.gov (United States)

    Liu, Jun

    A high fidelity in situ technique for measuring electrochemical noise data on carbon steel in alkaline solutions, referred to as Electrochemical Emission Spectroscopy (EES), or Electrochemical Noise Measurement (ENM), has been developed in this thesis as a means of monitoring general corrosion and pitting corrosion on carbon steel in simulated DOE nuclear waste storage systems and to develop a better understanding of the corrosion processes of carbon steel in these environments. The data acquisition system is essential to the accuracy of voltage and current measurements and the validity of experimental data for further analysis. Time and frequency domain analyses display different characteristics for general corrosion and pitting corrosion. DOE raw noise data analysis shows that the penetration corrosion rate in liquid/sludge phases is in the order of 10-2--10-3 mm/year for the carbon steel-lined tanks in the DOE waste environments. In addition, good correlation has been observed between EES and traditional Linear Polarization Resistance (LPR) method in detecting the corrosion rates of carbon steel. The passive state on iron in EDTA (ethylene diammine tetra acetic acid, disodium salt, C10H14N2Na2O 8)-containing borate buffer solutions of pH ranging from 8.15 to 12.87 at ambient temperature has been explored using Electrochemical Impedance Spectroscopy (EIS), another powerful in situ electrochemical method for investigating steady-state electrochemical and corrosion systems. It has been found that frequency sweep range, perturbation voltage amplitude, solution pH, and film formation voltage are important factors to influence the impedance of passive iron. The steady-state passive films formed on iron have been shown to satisfy the conditions of linearity, causality, stability and finiteness, on the basis of the good agreement observed between the experimental impedance data and the Kramers-Kronig transforms calculated data over most of the frequency range employed

  19. Austenite decomposition in carbon steel under dynamic deformation conditions

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  1. Corrosion Behavior of Carbon Steels in CCTS Environment

    Directory of Open Access Journals (Sweden)

    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.

  2. Carbon distribution in the martensite structure of structural steel

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Corrosion of steel tanks in liquid nuclear wastes

    International Nuclear Information System (INIS)

    The objective of this work is to understand how solution chemistry would impact on the corrosion of waste storage steel tanks at the Hanford Site. Future tank waste operations are expected to process wastes that are more dilute with respect to some current corrosion inhibiting waste constituents. Assessment of corrosion damage and of the influence of exposure time and electrolyte composition, using simulated (non-radioactive) wastes, of the double-shell tank wall carbon steel alloys is being conducted in a statistically designed long-term immersion experiment. Corrosion rates at different times of immersion were determined using both weight-loss determinations and electrochemical impedance spectroscopy measurements. Localized corrosion susceptibility was assessed using short-term cyclic potentiodynamic polarization curves. The results presented in this paper correspond to electrochemical and weight-loss measurements of the immersed coupons during the first year of immersion from a two year immersion plan. A good correlation was obtained between electrochemical measurements, weight-loss determinations and visual observations. Very low general corrosion rates (-1) were estimated using EIS measurements, indicating that general corrosion rate of the steel in contact with liquid wastes would no be a cause of tank failure even for these out-of-chemistry limit wastes. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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.

  11. Distribution of radionuclides during melting of carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. General corrosion of carbon steels in high temperature water

    International Nuclear Information System (INIS)

    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

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

    OpenAIRE

    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 ...

  14. Boric acid corrosion of carbon and low alloy steels

    International Nuclear Information System (INIS)

    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

  15. 75 FR 1495 - Certain Hot-Rolled Carbon Steel Flat Products From India: Preliminary Results of Countervailing...

    Science.gov (United States)

    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...

  16. 77 FR 45576 - Certain Hot-Rolled Carbon Steel Flat Products From the People's Republic of China: Preliminary...

    Science.gov (United States)

    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...

  17. 75 FR 1031 - Certain Hot-Rolled Carbon Steel Flat Products from India: Notice of Preliminary Results of...

    Science.gov (United States)

    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...

  18. Development of highly corrosion resistant 18-8 stainless steel for nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    Corrosion behavior of ultra low carbon 18-8 stainless steel was evaluated in boiling nitric acid environment. Although ultra low carbon stainless steel shows excellent corrosion resistance, it is, due to low carbon content, easily induced martensite by cold work. Increasing the strain induced martensite by cold work, the corrosion rate of 18-8 stainless steel increased. Corrosion rate is summarized as a function of stability factor with represents a resistance to martensite transformation induced by cold work and highly austenitic stabilized steel showed better corrosion resistance. Ultra low carbon 18-8 stainless steel which is highly stabilized austenite was designed and manufactured with commercial mill. The development steel showed an excellent corrosion resistance in boiling nitric acid even after cold work. The corrosion rate of the welded joint was also excellent as well as matrix

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

    International Nuclear Information System (INIS)

    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

  20. 48 CFR 225.7011 - Restriction on carbon, alloy, and armor steel plate.

    Science.gov (United States)

    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....

  1. 77 FR 65712 - Circular Welded Carbon-Quality Steel Pipe From Vietnam; Termination of Investigation

    Science.gov (United States)

    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....

  2. 75 FR 21658 - Carbon and Certain Alloy Steel Wire Rod From Trinidad and Tobago

    Science.gov (United States)

    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...

  3. 75 FR 44766 - Certain Welded Carbon Steel Standard Pipe from Turkey: Final Results of Countervailing Duty...

    Science.gov (United States)

    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...

  4. 77 FR 19623 - Certain Welded Carbon Steel Standard Pipe from Turkey: Preliminary Results of Countervailing Duty...

    Science.gov (United States)

    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...

  5. 78 FR 49255 - Certain Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Partial Rescission of...

    Science.gov (United States)

    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...

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

    International Nuclear Information System (INIS)

    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

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

    OpenAIRE

    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...

  8. Physicochemical and tribological characterization of titanium or titanium plus carbon implanted AISI M2 steel

    International Nuclear Information System (INIS)

    AISI M2 steel samples were implanted with 110 keV titanium ions at fluences ranging from 5x1016 to 4x1017Ti cm-2. Titanium plus carbon dual implantation was also studied. Titanium distribution profiles were determined using the 48Ti(p,γ)49V resonant nuclear reaction. The incorporation of carbon and oxygen from residual gases was studied as a function of titanium fluence and residual pressure using nuclear backscattering spectrometry at 5.7 and 7.5 MeV He+ ion energies respectively. A competition phenomenon between carbon and oxygen incorporation is pointed out. Analysis of the phases formed was performed using conversion electron Moessbauer spectroscopy. Fe(Ti) solid solution, a-FexTi100-x and superficial a-Fe-Ti-C amorphous phases were identified. Tribological tests involving a ball (Al2O3 or 52100) and disc contact were performed to characterize the friction behaviour of the implanted surface. It is shown that titanium plus carbon implantation leads to a reduction in the friction coefficient. The wear tracks and debris were examined using scanning electron microscopy and electron microprobe cartography. For the two types of balls a reduction in the wear track width was observed together with oxidation of the wear debris. The tribological improvement observed depends not only on the presence of the superficial a-Fe-Ti-C amorphous layer but also on the surface chemical reaction during the wear process. (orig.)

  9. Factors controlling hydrogen cracking during cladding of nuclear vessel steels

    International Nuclear Information System (INIS)

    During cladding of low alloy steels in nuclear pressure vessels for corrosion resistance, a potential problem exists of underclad hydrogen cracking. Research was undertaken to gain a better insight into the factors controlling underclad hydrogen cracking during cladding A508 Cl 3 nuclear vessel steels and to ensure the continued development of safe welding procedures in this critical application. The project was divided into three experimental phases. Phase I studied the potential and deposit hydrogen levels in Type 309 austenitic stainless steel and Ni alloy consumables and weld metals. Phase II incorporated implant testing of the A508 Cl 3 base material. A large test panel was fabricated in Phase III to approach the conditions of restraint and heat sink that are present in the pressure vessel cladding operation, but not necessarily those of the most critical components, such as nozzles where the cylindrical geometry may increase the overall restraint. The A508 Cl 3 test material was electron beam welded into the center of the test block which was then submerged arc-strip clad using very severe welding conditions in an attempt to generate underclad hydrogen cracks. It was found that for the shielded metal-arc welding (SMAW) and submerged arc welding (SAW) processes, deposit hydrogen levels were primarily controlled by flux moisture content. With single layer deposition, the implant test did not show evidence of the influence of segregation on cold cracking. All SMAW implant tests, without preheat and regardless of consumable, gave lower critical stress thresholds below about 51 ksi. A preheat of 150 deg.C increased this threshold to 80 ksi with Type 306 consumables. Even under welding conditions favorable for cracking, underclad hydrogen cracks could not be developed in a large-scale simulation of a cladding operation, indicating that very high total system restraint is needed to induce cracking

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

    Institute of Scientific and Technical Information of China (English)

    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.

  11. 75 FR 60814 - Carbon Steel Butt-Weld Pipe Fittings From Brazil, China, Japan, Taiwan, and Thailand

    Science.gov (United States)

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  13. 75 FR 22372 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's...

    Science.gov (United States)

    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...

  14. 75 FR 69050 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's...

    Science.gov (United States)

    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...

  15. 77 FR 64471 - Circular Welded Carbon-Quality Steel Pipe From the Socialist Republic of Vietnam: Final Negative...

    Science.gov (United States)

    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...

  16. 78 FR 33108 - Circular Welded Carbon-Quality Steel Pipe From China; Institution of Five-Year Reviews

    Science.gov (United States)

    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...

  17. 76 FR 24462 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Rescission of...

    Science.gov (United States)

    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...

  18. 77 FR 73674 - Circular Welded Carbon-Quality Steel Pipe From India, Oman, The United Arab Emirates, and Vietnam

    Science.gov (United States)

    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,...

  19. 78 FR 72863 - Circular Welded Carbon-Quality Steel Pipe From the People's Republic of China: Continuation of...

    Science.gov (United States)

    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...

  20. 75 FR 29519 - Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China: Rescission of...

    Science.gov (United States)

    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...

  1. 75 FR 67108 - Cut-To-Length Carbon Steel Plate From India, Indonesia, Italy, Japan, and Korea

    Science.gov (United States)

    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...

  2. 75 FR 21241 - Certain Cut-to-Length Carbon Steel Plate from the People's Republic of China: Initiation of...

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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...

  4. 77 FR 64478 - Circular Welded Carbon-Quality Steel Pipe From India: Final Determination of Sales at Less Than...

    Science.gov (United States)

    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...

  5. 78 FR 46570 - Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From Ukraine; Administrative Review

    Science.gov (United States)

    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...

  6. 77 FR 13093 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Final Results of...

    Science.gov (United States)

    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...

  7. 76 FR 34101 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    Science.gov (United States)

    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...

  8. 76 FR 8772 - Cut-to-Length Carbon Steel Plate From India, Indonesia, Italy, Japan and Korea

    Science.gov (United States)

    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...

  9. 77 FR 72827 - Corrosion-Resistant Carbon Steel Flat Products From Germany and the Republic of Korea: Final...

    Science.gov (United States)

    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...

  10. 77 FR 31877 - Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea; Scheduling of Full Five...

    Science.gov (United States)

    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...

  11. 76 FR 80963 - Cut-To-Length Carbon-Quality Steel Plate From India, Indonesia, Italy, Japan, and Korea

    Science.gov (United States)

    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...

  12. 78 FR 19210 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Final Results of...

    Science.gov (United States)

    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...

  13. 78 FR 72114 - Circular Welded Carbon Quality Steel Line Pipe From China; Institution of Five-Year Reviews

    Science.gov (United States)

    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...

  14. 77 FR 24221 - Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea; Notice of Commission...

    Science.gov (United States)

    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...

  15. 78 FR 67334 - Suspension Agreement on Certain Cut-to-Length Carbon Steel Plate From Ukraine; Final Results of...

    Science.gov (United States)

    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...

  16. 76 FR 66893 - Certain Circular Welded Carbon Steel Pipes and Tubes From India, Thailand, and Turkey; Final...

    Science.gov (United States)

    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...

  17. 76 FR 64900 - Welded Carbon Steel Pipe and Tube From Turkey: Final Results of Expedited Sunset Review of...

    Science.gov (United States)

    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...

  18. 76 FR 33204 - Certain Welded Carbon Steel Pipe and Tube From Turkey; Notice of Preliminary Results of...

    Science.gov (United States)

    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...

  19. 76 FR 76939 - Certain Welded Carbon Steel Pipe and Tube From Turkey: Notice of Final Results of Antidumping...

    Science.gov (United States)

    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...

  20. 78 FR 79665 - Welded Carbon Steel Standard Pipe and Tube Products From Turkey: Final Results of Antidumping...

    Science.gov (United States)

    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...

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

    Institute of Scientific and Technical Information of China (English)

    Huajie Wu; Yangchun Liu; Jie Fu

    2007-01-01

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

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

    OpenAIRE

    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...

  3. Effects of LWR coolant environments on fatigue design curves of carbon and low-alloy steels

    International Nuclear Information System (INIS)

    The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. Figures I-9.1 through I-9.6 of Appendix I to Section III of the code specify fatigue design curves for structural materials. While effects of reactor coolant environments are not explicitly addressed by the design curves, test data indicate that the Code fatigue curves may not always be adequate in coolant environments. This report summarizes work performed by Argonne National Laboratory on fatigue of carbon and low-alloy steels in light water reactor (LWR) environments. The existing fatigue S-N data have been evaluated to establish the effects of various material and loading variables such as steel type, dissolved oxygen level, strain range, strain rate, temperature, orientation, and sulfur content on the fatigue life of these steels. Statistical models have been developed for estimating the fatigue S-N curves as a function of material, loading, and environmental variables. The results have been used to estimate the probability of fatigue cracking of reactor components. The different methods for incorporating the effects of LWR coolant environments on the ASME Code fatigue design curves are presented

  4. Effects of LWR coolant environments on fatigue design curves of carbon and low-alloy steels

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, O.K.; Shack, W.J. [Argonne National Lab., IL (United States)

    1998-03-01

    The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. Figures I-9.1 through I-9.6 of Appendix I to Section III of the code specify fatigue design curves for structural materials. While effects of reactor coolant environments are not explicitly addressed by the design curves, test data indicate that the Code fatigue curves may not always be adequate in coolant environments. This report summarizes work performed by Argonne National Laboratory on fatigue of carbon and low-alloy steels in light water reactor (LWR) environments. The existing fatigue S-N data have been evaluated to establish the effects of various material and loading variables such as steel type, dissolved oxygen level, strain range, strain rate, temperature, orientation, and sulfur content on the fatigue life of these steels. Statistical models have been developed for estimating the fatigue S-N curves as a function of material, loading, and environmental variables. The results have been used to estimate the probability of fatigue cracking of reactor components. The different methods for incorporating the effects of LWR coolant environments on the ASME Code fatigue design curves are presented.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  6. Solidification of stainless steel slag by accelerated carbonation.

    Science.gov (United States)

    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

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

    OpenAIRE

    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. ...

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  10. Stress corrosion cracking of A515 grade 60 carbon steel

    International Nuclear Information System (INIS)

    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.)

  11. Corrosion inhibition of carbon steel by sodium metavanadate

    Directory of Open Access Journals (Sweden)

    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.

  12. Corrosion fatigue behavior of carbon steel in drilling fluids

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

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

    Institute of Scientific and Technical Information of China (English)

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

    2011-01-01

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

  17. Corrosion of carbon steel and Monel-400 in EDTA based steam generator cleaning formulations

    Energy Technology Data Exchange (ETDEWEB)

    Narasimhan, S.V.; Padma, S.; Veena, S.N.; Rufus, A.L.; Sathyaseelan, V.S.; Velmurugan, S. [Water and Steam Chemistry Lab., BARC Facilities Kalpakkam, Tamilnadu (India)

    2001-10-01

    Corrosion products and the scale forming impurities foul the steam generators of pressurized water reactors (PWR) and pressurized heavy water reactors (PHWR). The impurities from the make-up water, the condenser leaks and the corrosion product oxides leached from the feed train structural materials are carried along with the feed water and concentrate in the steam generators. These impurities deposit/precipitate over the steam generator surfaces and cause several problems such as reduction in heat transfer efficiency, under deposit attack, tube failures and production loss. In order to solve this problem, the power utilities are resorting increasingly to chemical cleaning of the steam generators. The chemical formulation selected for cleaning should be able to dissolve the accumulated corrosion products/sludge and at the same time should be compatible with the steam generator structural materials. Of the various chemical-cleaning formulations, the EDTA based formulations are more popular and have been used in the chemical cleaning of many nuclear steam generators. Its corrosion compatibility with the structural-materials of the steam generators needs a thorough evaluation. In this work, the effect of various additives added to the EDTA such as pH additive, reducing agent, oxidizing agent and corrosion inhibitors have been investigated. Increase in the concentration of hydrazine has been found to increase the corrosion rate of carbon steel. The variation in corrosion release from carbon steel with time was found to fit a second order equation. The variation in corrosion rate with time was attributed entirely to the increase in surface area caused by roughening of the surface. Presence of dissolved oxygen in EDTA based iron formulation enhanced the corrosion rate of carbon steel and pitted the Monel-400. The study indicated the need for strict oxygen control and the necessity of using a suitable corrosion inhibitor during the iron removal step. The role of copper in

  18. Thermal deformation behavior and microstructure of nuclear austenitic stainless steel

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Gleeble-1500D thermal simulation tester was employed in the hot-compression investigation of as-cast nuclear 304 austenitic stainless steel under conditions: deformation temperature 950―1200℃; deformations 30% and 50%; deformation rates 0.01 and 0.1 s?1. The results show that the flow stress decreases with temperature rise under the same strain rate and deformation, that the flow stress increases with deformation under the same temperature and strain rate, and that the flow stress increases with strain rate under the same temperature condition, i.e., work hardening becomes distinct. Materials exhibit better strength-toughness when the strain rate is 0.01 s-1, the deformation is 50%, and the temperature is 1050℃.

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

    Directory of Open Access Journals (Sweden)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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

  2. Carbon pricing, nuclear power and electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, R.; Keppler, J. H. [OECD Nuclear Energy Agency, 12, boulevard des Iles, 92130 Issy-les-Moulineaux (France)

    2012-07-01

    In 2010, the NEA in conjunction with the International Energy Agency produced an analysis of the Projected Costs of Electricity for almost 200 power plants, covering nuclear, fossil fuel and renewable electricity generation. That analysis used lifetime costs to consider the merits of each technology. However, the lifetime cost analysis is less applicable in liberalised markets and does not look specifically at the viewpoint of the private investor. A follow-up NEA assessment of the competitiveness of nuclear energy against coal- and gas-fired generation under carbon pricing has considered just this question. The economic competition in electricity markets is today between nuclear energy and gas-fired power generation, with coal-fired power generation not being competitive as soon as even modest carbon pricing is introduced. Whether nuclear energy or natural gas comes out ahead in their competition depends on a number of assumptions, which, while all entirely reasonable, yield very different outcomes. The analysis in this study has been developed on the basis of daily data from European power markets over the last five-year period. Three different methodologies, a Profit Analysis looking at historic returns over the past five years, an Investment Analysis projecting the conditions of the past five years over the lifetime of plants and a Carbon Tax Analysis (differentiating the Investment Analysis for different carbon prices) look at the issue of competitiveness from different angles. They show that the competitiveness of nuclear energy depends on a number of variables which in different configurations determine whether electricity produced from nuclear power or from CCGTs generates higher profits for its investors. These are overnight costs, financing costs, gas prices, carbon prices, profit margins (or mark-ups), the amount of coal with carbon capture and electricity prices. This paper will present the outcomes of the analysis in the context of a liberalised

  3. Carbon pricing, nuclear power and electricity markets

    International Nuclear Information System (INIS)

    In 2010, the NEA in conjunction with the International Energy Agency produced an analysis of the Projected Costs of Electricity for almost 200 power plants, covering nuclear, fossil fuel and renewable electricity generation. That analysis used lifetime costs to consider the merits of each technology. However, the lifetime cost analysis is less applicable in liberalised markets and does not look specifically at the viewpoint of the private investor. A follow-up NEA assessment of the competitiveness of nuclear energy against coal- and gas-fired generation under carbon pricing has considered just this question. The economic competition in electricity markets is today between nuclear energy and gas-fired power generation, with coal-fired power generation not being competitive as soon as even modest carbon pricing is introduced. Whether nuclear energy or natural gas comes out ahead in their competition depends on a number of assumptions, which, while all entirely reasonable, yield very different outcomes. The analysis in this study has been developed on the basis of daily data from European power markets over the last five-year period. Three different methodologies, a Profit Analysis looking at historic returns over the past five years, an Investment Analysis projecting the conditions of the past five years over the lifetime of plants and a Carbon Tax Analysis (differentiating the Investment Analysis for different carbon prices) look at the issue of competitiveness from different angles. They show that the competitiveness of nuclear energy depends on a number of variables which in different configurations determine whether electricity produced from nuclear power or from CCGTs generates higher profits for its investors. These are overnight costs, financing costs, gas prices, carbon prices, profit margins (or mark-ups), the amount of coal with carbon capture and electricity prices. This paper will present the outcomes of the analysis in the context of a liberalised

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

    Institute of Scientific and Technical Information of China (English)

    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

    Directory of Open Access Journals (Sweden)

    Zrník J.

    2006-01-01

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

  6. Long-term prediction of reinforced concrete structures - Use of thermodynamic data to assess steel corrosion in carbonated concrete

    International Nuclear Information System (INIS)

    In the context of the prediction of the long-term behaviour of reinforced concrete structures involved in the nuclear waste storage, the corrosion mechanisms of the steels have to be assessed and modelled. When nuclear wastes are embedded in reinforced concrete containers, the chemical environment of the reinforcement is progressively modified, due to the diffusion of the carbonation front inside the concrete matrix. This modification leads to the variation of the properties of the iron oxides formed at the steel/concrete interface, and the active corrosion can be initiated. In order to understand and modelled the mechanisms of steel corrosion in concrete, the equilibrium of two main systems must be separately described with the help of thermodynamic data issued from the literature: - The mineral phases, lime and calcium silicate hydrate (C-S-H), in equilibrium with the pore solution during the propagation of the carbonation front; - The iron oxides in equilibrium with the aqueous solution. For this purpose, the nature of aqueous species present in the pore solution was calculated in the whole range of pH encountered during the cement paste degradation by carbonation. As a matter of fact, as the pH decreases, calcium concentration decreases and silicates concentration increases due to the calcium carbonate formation and C-S-H dissolution. The pH of a carbonated concrete ranges between 8.3 and 10, depending on the partial pressure of carbon dioxide in the porosity and the conversion degree of carbonation. In this pH range, the iron oxides equilibria were analysed as a function of the redox potential and aqueous species (carbonates and sulphates present in the solution) present inside the solution. In a reductive solution and in presence of carbonates, the high solubility of iron oxides may prevent passivation or generate the dissolution of the passive film. Moreover, the relevance of thermodynamics calculations has been confirmed by corrosion tests of mild steel

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Science.gov (United States)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  10. Comparative study in the induced corrosion by sulfate reducing microorganisms, in a stainless steel 304L sensitized and a carbon steel API X65

    International Nuclear Information System (INIS)

    In spite of the operational experience related with the presence of the phenomenon of microbiological corrosion (MIC) in industrial components, it was not but until the decade of the 80 s when the nuclear industry recognized its influence in some systems of Nuclear Generating Power plants. At the moment, diverse studies that have tried to explain the generation mechanism of this phenomenon exist; however, they are even important queries that to solve, especially those related with the particularities of the affected metallic substrates. Presently work, the electrochemical behavior of samples of stainless steel AISI 304L sensitized is evaluated and the carbon steel APIX65, before the action of sulfate reducing microorganisms low the same experimental conditions; found that for the APIX65 the presence of this type of bacteria promoted the formation of a stable biofilm that allowed the maintenance of the microorganisms that damaged the material in isolated places where stings were generated; while in the AISI 304L, it was not detected damage associated to the inoculated media. The techniques of Resistance to the Polarization and Tafel Extrapolation, allowed the calculation of the speed of uniform corrosion, parameter that doesn't seem to be influenced by the presence of the microorganisms; while that noise electrochemical it distinguished in real time, the effect of the sulfate reducing in the steel APIX65. (Author)

  11. The role of nuclear power under carbon emission regulation

    International Nuclear Information System (INIS)

    The role of nuclear power under the carbon emission regulation was analyzed in a national economy. In order to see how much influences does the carbon emission regulation has on the national economy, scenarios on the carbon emission regulations were established. Additional scenarios on the nuclear power option (with or without) was also established to capture the role of nuclear power generation under the carbon emission regulations. The study shows that the most favorable case is, as expected, weak regulation with nuclear option, the next is strong regulation with nuclear option, followed by weak regulation without nuclear option, and the most serious case is strong regulation without nuclear option. The results from this study implies that the national economy impacts depends more on nuclear scenarios than on carbon emission regulation scenarios. The results place special emphasis on the importance of the role of nuclear power under the carbon emission regulation

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Fuel choice, nuclear energy, climate and carbon

    International Nuclear Information System (INIS)

    For the second time since the start of commercial nuclear electricity generation, an accident has the world wondering if uranium will be among the future fuel choices in electricity production. Unfortunate when one considers the low-carbon footprint of this energy option. An accident involving a nuclear power plant, or more appropriately the perceived risks associated with an accident at a nuclear power plant, is but one of the issues that makes the impact assessment process related to nuclear energy projects challenging. Other aspects, including the time scales associated with their siting, licensing, operation and decommissioning, also contribute to the challenge. Strategic environmental assessments for future fuel choices in electricity generation, particularly ones that consider the use of life cycle assessment information, would allow for the effective evaluation of the issues identified above. But more importantly from an impact assessment perspective, provide for a comparative assertion for public disclosure on the environmental impacts of fuel choice. This would provide the public and government decision makers with a more complete view of the role nuclear energy may be able to play in mitigating the climate and carbon impacts of increased electricity production, and place issues of cost, complexity and scale in a more understandable context.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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.

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

    OpenAIRE

    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.

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

    Science.gov (United States)

    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.

  18. Statistical analysis of fatigue strain-life data for carbon and low-alloy steels

    International Nuclear Information System (INIS)

    The existing fatigue strain vs life (S-N) data, foreign and domestic, for carbon and low-alloy steels used in the construction of nuclear power plant components have been compiled and categorized according to material, loading, and environmental conditions. A statistical model has been developed for estimating the effects of the various test conditions on fatigue life. The results of a rigorous statistical analysis have been used to estimate the probability of initiating a fatigue crack. Data in the literature were reviewed to evaluate the effects of size, geometry, and surface finish of a component on its fatigue life. The fatigue S-N curves for components have been determined by applying design margins for size, geometry, and surface finish to crack initiation curves estimated from the model

  19. 76 FR 67407 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Notice of Preliminary Results of Antidumping...

    Science.gov (United States)

    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,...

  20. 76 FR 62039 - Certain Hot-Rolled Carbon Steel Flat Products From India: Final Results of 2009-2010 Antidumping...

    Science.gov (United States)

    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...

  1. 76 FR 42679 - Certain Hot-Rolled Carbon Steel Flat Products From India: Final Results of Antidumping Duty...

    Science.gov (United States)

    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)...

  2. 75 FR 27297 - Certain Hot-Rolled Carbon Steel Flat Products from India: Notice of Final Results of Antidumping...

    Science.gov (United States)

    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...

  3. 76 FR 31938 - Certain Hot-Rolled Carbon Steel Flat Products From India: Notice of Preliminary Results of 2009...

    Science.gov (United States)

    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,...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  8. 75 FR 69125 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From China

    Science.gov (United States)

    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...

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

    International Nuclear Information System (INIS)

    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.

  10. 77 FR 54926 - Certain Seamless Carbon and Alloy Steel; Standard, Line, and Pressure Pipe From Germany

    Science.gov (United States)

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  12. 78 FR 34335 - Certain Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Preliminary Results of...

    Science.gov (United States)

    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:...

  13. 75 FR 36635 - Circular Welded Carbon Steel Pipes and Tubes From Thailand: Rescission of Antidumping Duty...

    Science.gov (United States)

    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...

  14. 77 FR 44213 - Corrosion-Resistant Carbon Steel Flat Products From Germany and the Republic of Korea...

    Science.gov (United States)

    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...

  15. 75 FR 62566 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil, Japan, and Russia

    Science.gov (United States)

    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,...

  16. 78 FR 40429 - Certain Hot-Rolled Carbon Steel Flat Products From India: Rescission of Countervailing Duty...

    Science.gov (United States)

    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...

  17. 76 FR 26694 - Certain Hot-Rolled Carbon Steel Flat Products From India: Final Rescission of Countervailing Duty...

    Science.gov (United States)

    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...

  18. 78 FR 40428 - Certain Hot-Rolled Carbon Steel Flat Products from India: Rescission of Antidumping Duty...

    Science.gov (United States)

    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...

  19. 78 FR 55241 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Preliminary Results of...

    Science.gov (United States)

    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...

  20. 78 FR 16832 - Corrosion-Resistant Carbon Steel Flat Products From Germany and the Republic of Korea: Revocation...

    Science.gov (United States)

    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...

  1. 77 FR 47593 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Preliminary Results...

    Science.gov (United States)

    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...

  2. 78 FR 76279 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Final Results and...

    Science.gov (United States)

    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...

  3. 75 FR 8301 - Certain Cut-to-Length Carbon Steel Plate From the People's Republic of China: Final Results of...

    Science.gov (United States)

    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...

  4. 75 FR 2487 - Circular Welded Carbon Steel Pipes and Tubes from Thailand: Court Decision Not in Harmony with...

    Science.gov (United States)

    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...

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

    International Nuclear Information System (INIS)

    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

  6. Evaluation of effects of LWR coolant environments on fatigue life of carbon and low-alloy steels

    International Nuclear Information System (INIS)

    The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. Figure I-90 of Appendix I to Section III of the Code specifies fatigue design curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the Code design curves. Recent test data indicate a significant decrease in fatigue life of carbon and low-alloy steels in LWR environments when five conditions are satisfied simultaneously, viz., applied strain range, temperature, dissolved oxygen in the water, and sulfur content of the steel are above a minimum threshold level, and the loading strain rate is below a threshold value. Only a moderate decrease in fatigue life is observed when any one of these conditions is not satisfied. This paper summarizes available data on the effects of various material and loading variables such as steel type, dissolved oxygen level, strain range, strain rate, and sulfur content on the fatigue life of carbon and low-alloy steels. The data have been analyzed to define the threshold values of the five critical parameters. Methods for estimating fatigue lives under actual loading histories are discussed

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

    OpenAIRE

    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.

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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)

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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)

  12. Welding of stainless steel clad fuel rods for nuclear reactors

    International Nuclear Information System (INIS)

    This work describes the obtainment of austenitic stainless steel clad fuel rods for nuclear reactors. Two aspects have been emphasized: (a) obtainment and qualification of AISI 304 and 304 L stainless steel tubes; b) the circumferential welding of pipe ends to end plugs of the same alloy followed by qualification of the welds. Tubes with special and characteristic dimensions were obtained by set mandrel drawing. Both, seamed and seamless tubes of 304 and 304 L were obtained.The dimensional accuracy, surface roughness, mechanical properties and microstructural characteristics of the tubes were found to be adequate. The differences in the properties of the tubes with and without seams were found to be insignificant. The TIG process of welding was used. The influence of various welding parameters were studied: shielding gas (argon and helium), welding current, tube rotation speed, arc length, electrode position and gas flow. An inert gas welding chamber was developed and constructed with the aim of reducing surface oxidation and the heat affected zone. The welds were evaluated with the aid of destructive tests (burst-test, microhardness profile determination and metallographic analysis) and non destructive tests (visual inspection, dimensional examination, radiography and helium leak detection). As a function of the results obtained, two different welding cycles have been suggested; one for argon and another for helium. The changes in the microstructure caused by welding have been studied in greater detail. The utilization of work hardened tubes, permitted the identification by optical microscopy and microhardness measurements, of the different zones: weld zone; heat affected zone (region of grain growth, region of total and partial recrystallization) and finally, the zone not affected by heat. Some correlations between the welding parameters and metallurgical phenomena such as: solidification, recovery, recrystallization, grain growth and precipitation that occurred

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

    OpenAIRE

    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...

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

    International Nuclear Information System (INIS)

    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

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

    OpenAIRE

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Welding of stainless steel pool of pressurized water reactor nuclear power station

    International Nuclear Information System (INIS)

    The construction of stainless steel lining of million kilowatt grade pressurized water reactor nuclear power station is a new technology. The author introduces its welding method, parameter verification measure and key factors of construction quality control and so on

  18. Nuclear power and the carbon dioxide problem

    International Nuclear Information System (INIS)

    This study deals with the question, which contribution can be delivered by nuclear power to the redution of the emission of carbon dioxide (CO2) from the power supply. The emphasis lays upon the following aspects: the emissions of CO2 which occur in the nuclear-power cycle (the so-called indirect emission of CO2 power plants); the amount of uranium stocks; the change of CO2 emission caused by replacement of fossil fuels, in particular coal, by nuclear power. First an energy-analysis of the nuclear power cycle is presented. On the base of this analysis the CO2 uranium can be calculated. The role of nuclear power in the reduction of CO2 emission depends on the development of the final power demand. Therefore in this study two scenarios derived from the 'IIASA-low' scenario; 'low-energy'-scenario in which the world-energy consumption remains at about the same level. In the calculations the indirect emissions of CO2, also dependent on the ore richness and the technology used, have always been taken into account. In the calculations two uranium-reserve variants of resp. 5.7 and 30 mln. tons have been assumed. From the results of the calculations it can be concluded that whether or not taking account of the indirect emissions of CO2 in the nuclear power cycle, has only limited effect on the calculated contribution of nuclear power to the solution of the greenhouse effect. The uranium reserves turn out to be determining for the potential contribution of nuclear power. By putting on the surely available reserve of 5.7 mln. tons, or the speculative reserve of 30 mln. tons, with the actual technology, an emission of resp. 130-140 billion and 880 billion tons CO2 can be avoided in replacing coal. With maximal employment of improved conversion techniques these contributions may be doubled. (H.W.). 40 refs.; 13 figs.; 10 tabs

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Decontamination and decarburization of stainless and carbon steel by melt refining

    International Nuclear Information System (INIS)

    With many nuclear reactors and facilities being decommissioned in the next ten to twenty years the concern for handling and storing Radioactive Scrap Metal (RSM) is growing. Upon direction of the DOE Office of Environmental Restoration and Waste Management, Lockheed Idaho Technology Company (LITCO) is developing technologies for the conditioning of spent fuels and high-level wastes for interim storage and repository acceptance, including the recycling of Radioactive Scrap Metals (RSM) for beneficial reuse with the DOE complex. In February 1993, Montana Tech of the University of Montana was contracted to develop and demonstrate technologies for the decontamination of stainless steel RSM. The general objectives of the Montana Tech research program included conducting a literature survey, performing laboratory scale melt refining experiments to optimize decontaminating slag compositions, performing an analysis of preferred melting techniques, coordinating pilot scale and commercial scale demonstrations, and producing sufficient quantities of surrogate-containing material for all of the laboratory, pilot and commercial scale test programs. Later on, the program was expanded to include decontamination of carbon steel RSM. Each research program has been completed, and results are presented in this report

  1. Using artificial neural networks to predict the fatigue life of carbon and low-alloy steels

    International Nuclear Information System (INIS)

    The ASME boiler and pressure vessel code contains rules for the construction of nuclear power plant components. Figures I-9.1 through I-9.6 of Appendix I to Section III of the Code specify fatigue design curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the code design curves. Recent test data indicate significant decreases in the fatigue lives of carbon and low-alloy steels in LWR environments when five conditions are satisfied simultaneously. When applied strain range, temperature, dissolved oxygen in the water, and sulfur content of the steel are above a minimum threshold level, and the loading strain rate is below a threshold value, environmentally assisted fatigue occurs. For this study, a data base of 1036 fatigue tests was used to train an artificial neural network (ANN). Once the optimal ANN was designed, ANN were trained and used to predict fatigue life for specified sets of loading and environmental conditions. By finding patterns and trends in the data, the ANN can find the fatigue life for any set of conditions. Artificial neural networks show great potential for predicting environmentally assisted corrosion. Their main benefits are that the fit of the data is based purely on data and not on preconceptions and that the network can interpolate effects by learning trends and patterns when data are not available. (orig.)

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

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

    Institute of Scientific and Technical Information of China (English)

    Maoyu ZHAO; Qianwang CHEN

    2013-01-01

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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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)

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

    OpenAIRE

    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...

  9. Effects of materials and water chemistry factors on FAC rate of carbon steels

    International Nuclear Information System (INIS)

    Pipe wall thinning due to flow accelerated corrosion (FAC) is one of the most important degradation modes which can take place in nuclear power plants. Potential area of FAC is widespread in piping systems and probability of pipe failure due to FAC is relatively high compared to other causes. FAC is a complex phenomenon, where mass transfer under turbulent flow, chemical reactions at interfaces, and mass diffusion in oxide scales cooperatively or competitively interact. Among a number of influencing parameters for FAC rate, this paper focuses on Cr in carbon steels and pH of water. pH is the primary water chemistry parameter to manage FAC susceptibility of the whole piping systems. Small amount of Cr has a significant effect for improving resistance of the carbon steels to FAC. This fact offers an effective countermeasure for FAC mitigation by using Cr modified steels, but, at the same time, the Cr dependence could give difficult problems, when we manage pipe wall thinning with thickness inspections. In a procedure to sample piping lines and locations of thickness measurement, we may need to take into account Cr content of the pipes picked up for the inspection. We also need to pay attention on difference in Cr content between pipes and weld filler metal, even though the absolute Cr levels of the both steels are minor. In the cases that Cr content of weld metal is lower than that of pipe materials, circumferential grooving may form along the weld. Basically, effects of those material and water chemistry factors can be attributed to oxide scale properties, such as solubility to water, porosity, semiconductor property, etc. This paper briefly reviews experimental data of Cr, Ni, Cu effects and of pH effects, including both widely recognized 'historical' data and recent data on combined effects of Cr content and pH obtained by the authors. Characteristics of oxide scales formed in the FAC experiments, such as defect characteristics and Cr enrichment distribution, and

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Nuclear power and carbon dioxide free automobiles

    International Nuclear Information System (INIS)

    Nuclear energy has been developed as a major source of electric power in Canada. Electricity from nuclear energy already avoids the emission of about 100 million tonnes of carbon dioxide to the atmosphere in Canada. This is a significant fraction of the 619 million tonnes of Canadian greenhouse gas emissions in 1995. However, the current scope of application of electricity to end use energy needs in Canada limits the contribution nuclear energy can make to carbon dioxide emission reduction. Nuclear energy can also contribute to carbon dioxide emissions reduction through expansion of the use of electricity to less traditional applications. Transportation, in particular contributed 165 million tonnes of carbon dioxide to the Canadian atmosphere in 1995. Canada's fleet of personal vehicles consisted of 16.9 million cars and light trucks. These vehicles were driven on average 21,000 km/year and generated 91 million tonnes of greenhouse gases expressed as a C02 equivalent. Technology to improve the efficiency of cars is under development which is expected to increase the energy efficiency from the 1995 level of about 10 litres/100 km of gasoline to under 3 litres/100km expressed as an equivalent referenced to the energy content of gasoline. The development of this technology, which may ultimately lead to the practical implementation of hydrogen as a portable source of energy for transportation is reviewed. Fuel supply life cycle greenhouse gas releases for several personal vehicle energy supply systems are then estimated. Very substantial reductions of greenhouse gas emissions are possible due to efficiency improvements and changing to less carbon intensive fuels such as natural gas. C02 emissions from on board natural gas fueled versions of hybrid electric cars would be decreased to approximately 25 million t/year from the current 91 million tonnes/year. The ultimate reduction identified is through the use of hydrogen fuel produced via electricity from CANDU power

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

    International Nuclear Information System (INIS)

    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)

  13. Application of carbon fiber reinforced carbon composite to nuclear engineering

    International Nuclear Information System (INIS)

    Carbon fiber reinforced carbon matrix composite (C/C composite) is thought to be one of promising structural materials with high temperature resistivity in the nuclear engineering field. In the high temperature gas-cooled reactors with gas outlet temperature maximum around 1000degC, high performance core internal structures, such as control rod sheath, core restraint mechanism, will be expected to achieve by the C/C composite application. Moreover, in the fusion reactors, plasma facing structures having high temperature with high neutron irradiation and particle collision will be expected to achieve by the C/C composite application. In this paper, current research and development studies of the C/C composite application on both reactors are reviewed and vista of the future on the C/C composite application is mentioned. (author)

  14. Critical cleavage fracture stress characterization of A508 nuclear pressure vessel steels

    International Nuclear Information System (INIS)

    The critical cleavage fracture stress of SA508 Gr.4N and SA508 Gr.3 low alloy reactor pressure vessel (RPV) steels was studied through the combination of experiments and finite element method (FEM) analysis. The results showed that the value of the local cleavage fracture stress, σF, of SA508 Gr.4N steel was significantly higher than that of SA508 Gr.3 steel. Detailed microstructural analysis was carried out using FEGSEM which revealed much smaller grains, finer and more homogenous carbide particles formed in SA508 Gr.4N steel. Compared with the SA508 Gr.3 steel currently used in the nuclear industry, the SA508 Gr.4N steel possesses higher strength and notch toughness as well as improved cleavage fracture behavior, and is considered a better candidate RPV steel for the next generation nuclear reactors. - Highlights: • Critical cleavage fracture stress was calculated through experiments and FEM. • Effects of both grain and carbide particle sizes on σF were discussed. • The SA508 Gr.4N steel is a better candidate for the next generation nuclear reactors

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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.

  18. 76 FR 7546 - Certain Hot-Rolled Carbon Steel Flat Products From Brazil: Rescission of Countervailing Duty...

    Science.gov (United States)

    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...

  19. Predictive models for determination of pitting corrosion versus inhibitor concentrations and temperature for radioactive sludge in carbon steel waste tanks

    International Nuclear Information System (INIS)

    Statistical models were developed to predict the occurrence of pitting corrosion in carbon steel (CS) waste storage tanks exposed to radioactive nuclear waste. Levels of nitrite (NO2-) concentrations necessary to inhibit pitting at various temperatures and nitrate (NO3-) concentrations were determined experimentally via electrochemical polarization and coupon immersion corrosion tests. Models for the pitting behavior were developed based upon various statistical analyses of the experimental data. Freed-forward, artificial neural network (ANN) models, trained using the back-propagation of error algorithm, more accurately predicted conditions at which pitting occurred than the logistic regression models development using the same data

  20. Progress and teachings of stress corrosion cracking of low-carbon stainless steels used in BWR NPP (4)

    International Nuclear Information System (INIS)

    In the structural integrity evaluations of low-carbon stainless- or austenitic steel- made shrouds and primary loop recirculation (PLR) pipes used in Boiling Water Reactor Nuclear Power Plants, the stress corrosion crack propagation rates (crack depth) near shroud and near PLR pipe weld joints are assessed from the welding residual stress distribution obtained by the finite element method and by mockup testing, respectively. The structural integrity is evaluated by the plastic and the elastic-plastic fracture mechanics evaluation methods, respectively. (K. Kato)

  1. Material properties of a dissimilar metal weld Inconel 600/ Inconel 82 weld filler/ Carbon Steel (Gr.106 B)

    International Nuclear Information System (INIS)

    Inconel 600 pipes welded to Carbon-Steel are used in CANDU nuclear reactors. Fracture of these welded pipes has important consequences in term of safety, and therefore their mechanical properties need to be better understood. In this study, the weld region was analyzed at various length-scales using optical microscopy, micro hardness testing, small and large scale tensile testing, and Digital Image Correlation (DIC). Micro-hardness profiles showed variations across the weld and through thickness and were justified in terms of residual stresses. Local stress-strain curves were built using DIC and showed good agreement with stress-strain curves obtained from miniature tensile samples. (author)

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Nanoscopic strength analysis of work-hardened low carbon austenitic stainless steel, 316SS

    International Nuclear Information System (INIS)

    Stress corrosion cracking (SCC) occurs in shrouds and piping of low carbon austenitic stainless steels at nuclear power plants. A work-hardened layer, where the transgranular SCC initiates, is considered to be one of the probable cause for this occurrence. In order to clarify the microstructural characteristics of work-hardened layer at the surface of shrouds or piping, the strengthen analysis of low carbon austenitic stainless steel, 316SS, rolled at the reduction in area, RA, of 10, 20, 30, 40 and 50% at room temperature were conducted on a nanoscopic scale, using an ultra-microhardness tester, TEM and SEM. TEM and SEM observation showed that the microstructural parameters are the dislocation cell size, dcel, coarse slip spacing, lcsl, and austenitic grain size, dγ. Referring 10dcel and 10lcsl, Vickers hardness, HV, corresponding to macro strength was expressed as Hυ=Hυ*bas + Hυ*sol + Hυ*dis + Hυ*cel + Hυ*csl. Hυ*bas (=100) is the base hardness, Hυ*sol is the solid solution strengthening hardness, Hυ*dis is the dislocation strengthening hardness in the dislocation cell, and Hυ*cel and Hυ*csl are the fine grain strengthening hardness due to the dislocation cell and coarse slip. Hυ*sol was about 50, independently of RA. Hυ*dis was zero at RA 30%. Hυ*cel and Hυ*csl increased with increasing in RA and were kept constant at about 50 and 120 at RA=20 and 30%, respectively. It was suggested from these results that all dislocations introduced by rolling might be dissipated for the creation of dislocation cells and coarse slips at RA 30%. (author)

  4. Nuclear pumping of a neutral carbon laser

    International Nuclear Information System (INIS)

    Nuclear pumped lasing on the neutral carbon line at 1.45 μ has been achieved in mixtures of He-CO, He-CO2, Ne-CO and Ne-CO2. A low thermal neutron flux of 2 x 1014 n/cm2-sec was required and delays of up to 5.5 ms were observed. Helium pressures ranged from 20-800 T, Ne from 100-200 T, CO from 0.25 to 20 mT and CO2 from 0.1 to 25 mT

  5. 75 FR 18788 - Circular Welded Carbon Steel Pipes and Tubes from Thailand: Preliminary Results and Rescission...

    Science.gov (United States)

    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...

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  12. Ductile fracture behavior of 6-inch diameter type 304 stainless steel and STS 42 carbon steel piping containing a through-wall or part-through crack

    International Nuclear Information System (INIS)

    The double ended guillotine break philosophy in the design base accident of the nuclear power plant is considered to be overly conservative from the view point of piping design. Through the past experiences and developments of the fabrication, inspection, and operation of nuclear power plants, it has been recognized that the Leak-Before-Break (LBB) concept can be justified in the LWR pressure boundary pipings. In order to verify the LBB concept, extensive experimental and theoretical works are being conducted in many countries. Furthermore, a revised piping design standard, in which LBB concept is introduced, is under preparation in Japan, U.S.A., and European countries. At JAERI, a research program to investigate the unstable ductile fracture behavior of LWR piping under bending load has been carried out as a part of the LBB verification researches since 1983. This report summarizes the result of the ductile fracture tests conducted at room temperature in 1983 and 84. The 6-inch diameter pipes of type 304 stainless steel and STS 42 carbon steel pipe with a through-wall or part-through crack were tested under bending load with low or high compliance condition at room temperature. Pipe fracture data were obtained from the test as regards to load- displacement curve, crack extension, net section stress, J-resistance curve, and so on. Besides, the influence of the compliance on the fracture behavior was examined. Discussions are performed on the ductile pipe fracture criterion, flaw evaluation criterion, and LBB evaluation method. (author)

  13. Effects of nonstandard heat treatment temperatures on tensile and Charpy impact properties of carbon-steel casting repair welds

    International Nuclear Information System (INIS)

    This report discusses carbon steel castings which are used for a number of different components in nuclear power plants, including valve bodies and bonnets. Components are often repaired by welding processes, and both welded components and the repair welds are subjected to a variety of postweld heat treatments (PWHT) with temperatures as high as 899 degrees C (1650 degrees F), well above the normal 593 to 677 degrees C (1100 to 1250 degrees F) temperature range. The temperatures noted are above the A1 transformation temperature for the materials used for these components. A test program was conducted to investigate the potential effects of such ''nonstandard'' PWHTs on mechanical properties of carbon steel casting welds. Four weldments were fabricated, two each with the shielded-metal-arc (SMA) and flux-cored-arc (FCA) processes,with a high-carbon and low-carbon filler metal in each case. All four welds were sectioned and given simulated PWHTs at temperatures from 621 to 899 degrees C (1150 to 1650 degrees F) in increments of 56 degrees C (100 degrees F) and for times of 5, 10, 20, and 40 h at each temperature. Hardness, tensile, and Charpy V-notch (CVN) impact tests were conducted for the as-welded and heat-treated conditions

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

    International Nuclear Information System (INIS)

    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

  15. Experimental fracture studies on carbon steel elbows with and without internal pressure

    International Nuclear Information System (INIS)

    Pipe bends or elbows are commonly used components for nuclear power plant piping system. In service, these piping components are subjected to internal pressure in addition to bending loads and the internal pressure is known to have a significant effect on the load carrying capacity of these components. Hence, a systematic study was carried out to investigate and quantify the effect of internal pressure on the fracture behaviour of elbows used in nuclear power plant piping system. Fracture studies were conducted on five 219 mm diameter carbon steel elbows with and without internal pressure under in-plane opening moment. The investigations have shown that the presence of a circumferential notch at the intrados has a more detrimental effect on the fracture behaviour of the elbow, when compared with the presence of an axial notch at the intrados. It is also found that internal pressure plays a significant role in reducing the ovalization. -- Highlights: • Fracture studies were conducted on elbows with and without internal pressure. • Effect of internal pressure on load carrying capacity of the elbows was studied. • Various data acquired during the study include load, LLD, CMOD, ovality of the elbow. • Circumferential notch at intrados significantly affects elbow load carrying capacity

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

    International Nuclear Information System (INIS)

    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

    Energy Technology Data Exchange (ETDEWEB)

    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

    International Nuclear Information System (INIS)

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    International Nuclear Information System (INIS)

    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)

  1. Microbiologically influenced corrosion of stainless steel tubing and piping in the service water system at North Anna Nuclear Power Station

    International Nuclear Information System (INIS)

    Since original plant construction in the 1970's, the carbon steel piping of the service water system (SWS) of Virginia Power's North Anna Nuclear Power Station has experienced general corrosion and pitting due to microbiologically influenced corrosion (MIC). Corrosion of the carbon steel piping was combatted by the implementation of chemical treatment of the SWS and by repair/replacement of portions of the piping utilizing type 316L stainless steel (SS) on 10 in. and smaller piping and 100% solids epoxy coating on the rest of the piping. Only recently, in early 1994, MIC was discovered on the 18 gage 304 S welded tubes in the Component Cooling Heat Exchangers (CCHXs). Earlier, MIC was discovered on 316L SS pipe base metal adjacent to several socket weld locations on small diameter piping. This paper will concentrate on the Virginia Power action plan to combat further degradation due to MIC and to maintain operable SS piping and equipment with SS tubing which is exposed to service water

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

    International Nuclear Information System (INIS)

    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)

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  6. New structural high strength rationally alloyed steels

    International Nuclear Information System (INIS)

    New developments in high strength structural steels are reported. Properties and perspective fields of application are described for the following materials: austenitic chromium steels with ultra equilibrium nitrogen content, steels with nitrogen martensite structure, microalloyed ferritic-pearlitic steels with decreased concentrations of Mn and Ni, high ductility heat resisting steels, nonmagnetic chromium free Mn-Ni-Cu-V-C steels and iron powder alloys with superhard carbon phases. Steel 02Kh12G14N4YuM is recommended to be used for parts and assemblies of nuclear power plants

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

    Science.gov (United States)

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

    2003-10-01

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

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

    International Nuclear Information System (INIS)

    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...

    Science.gov (United States)

    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

    OpenAIRE

    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

    Institute of Scientific and Technical Information of China (English)

    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

    OpenAIRE

    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

    OpenAIRE

    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

    Institute of Scientific and Technical Information of China (English)

    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

    OpenAIRE

    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

    Science.gov (United States)

    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

    Institute of Scientific and Technical Information of China (English)

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

    Science.gov (United States)

    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

  19. Deformation resistance of steels for pressure vessels for nuclear power stations

    International Nuclear Information System (INIS)

    The development of nuclear power engineering in Czechoslovakia results in the increase in the number of produced components for nuclear power stations, such as rings, pipe bends, and dished ends produced from low- and high-alloy steels, etc. The systems produced for the VVER 1000 type nuclear power stations are considerably larger than those for VVER 440. The results show that many of these systems must be produced by hot pressing and, because of the dimensions, the initial material must have the form of thick plates or forgings. Pressing is carried out in high-power forging presses, often at the upper limit of the technological possibilities of the existing systems. It is therefore essential to have sufficient data on the strain capacity of the steels used for the production of components for nuclear power stations which can then be used to determine the optimum forming conditions. The components for the nuclear power stations are usually produced from 10GN2MFA low-alloy steel and 08Kh18N10T high-alloy steel. The aim of this work was to determine the mathematical dependences of the deformation resistance of these steels in the thermomechanical conditions in hot deformation. The results of torsion tests were used for this purpose. (author)

  20. Estimates of margins in ASME Code strength values for stainless steel nuclear piping

    International Nuclear Information System (INIS)

    The margins in the ASME Code stainless steel allowable stress values that can be attributed to the variations in material strength are evaluated for nuclear piping steels. Best-fit curves were calculated for the material test data that were used to determine allowable stress values for stainless steels in the ASME Code, supplemented by more recent data, to estimate the mean stresses. The mean yield stresses from the test data are about 15 to 20% greater than the ASME Code yield stress values (the stainless steel Sm values are based on the yield stress). The ASME Code yield stress values are estimated to approximately coincide with the 97% confidence limit from the test data. The mean and 97% confidence limit values can be used in probabilistic risk assessments of nuclear piping

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    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.

  3. Ladle refining of steels for nuclear power engineering

    International Nuclear Information System (INIS)

    A method of efficient desulphurising of steel is described. This uses ladle refining and enables a final sulphur content in the melt of less than 0.005% to be achieved. Using a conventional fireclay melt the content may be up to 0.008%. This method of ladle refining has been used to produce steels of low sulphur content for the VVER type 1000 reactors. The desulphurisation programme is explained. (author)

  4. Corrosion-resistant Foamed Cements for Carbon Steels

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    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)

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

    Institute of Scientific and Technical Information of China (English)

    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.

  9. Smelting of contaminated steel scrap arising in the dismantling of nuclear power plant

    International Nuclear Information System (INIS)

    In this work scrap steel components from nuclear power plants, about 2 t in all, have been studied during 16 melts and the melt products in these or in subsequent production melts brought below a de minimis (reclaim) radioactivity concentration of 10 pCi g-1. Radioactivity inventories for furnace systems have been made by means of further melts with known amounts of radioactivities applied to steel surfaces as simulated contamination. In addition there have been melts with known amounts of radioactivities diluted uniformly into steel to provide sample calibration standards but also to directly measure dosage for various configurations and thicknesses of plate rolled from the steel. The work shows: that Co-60 has in all cases finished entirely in steel and in uniform dilution in both electric arc and induction furnace melting. That Cs radioactivities do not enter steel at all and can readily be made to stay substantially in slag in the induction furnace. Under certain circumstances which may not be fully practical in production furnaces, caesium can be retained in slag in the electric arc furnace. These results together permit combined dilution/decontamination reclaim of selected nuclear steel scrap. (author)

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

    International Nuclear Information System (INIS)

    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.

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

    International Nuclear Information System (INIS)

    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.)

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

    International Nuclear Information System (INIS)

    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

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

    Directory of Open Access Journals (Sweden)

    J. Zrnik

    2009-07-01

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

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

  16. 75 FR 75455 - Certain Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil: Final Results of Full...

    Science.gov (United States)

    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...

  17. 76 FR 36081 - Hot-Rolled Flat-Rolled Carbon-Quality Steel Products From Brazil and Japan: Revocation of the...

    Science.gov (United States)

    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...

  18. Application of a new processing procedure for the further improvement of nuclear grade structural VCD steels

    International Nuclear Information System (INIS)

    The enhancement of the quality of NiCrMoV-steels for turbine rotors and generator shafts by use of the vacuum carbon deoxidation (VCD) method is well known and established. So far the application of the VCD method has been limited to those steels which were not required to be made as fine grained steels and which consequently could by produced without addition of Aluminium. Kloeckner Works have developed a method which allows the use of VCD - i.e. deoxidation of the steel by gaseous CO-reaction - with subsequent addition of Al for grain refinement. This new steel making process combines the advantages of a VCD steel with those of a fine grained steel. Seven production ingots of the steel 20 MnMoNi 5 5 have been produced by this process. The properties of the forgings made of these ingots are compared with forgings of Si/Al-deoxidized ingots. The VCD method has a beneficial influence on A-segregations. Sulphur prints show practically no segregation streaks. An improvement of impact properties and a greater isotropy of properties is gained by the VCD method. (orig.)

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

    International Nuclear Information System (INIS)

    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)

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    International Nuclear Information System (INIS)

    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)

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

    OpenAIRE

    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 ...

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

    OpenAIRE

    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...

  4. Features and mechanism of unusual wall thinning. (Erosion-corrosion) of the carbon steel pipe carrying hot pure water

    International Nuclear Information System (INIS)

    The features of unusual wall thinning of carbon steel piping used in the transport of pure water at elevated temperatures are described. The case of Mihama nuclear power plant is used as a typical example, since the results of investigations conducted by the investigation committee of the Nuclear and Industrial Safety Agency are already available at their web site, and detailed information, such as data on residual wall thickness distribution and clear photographs of the thinned pipe wall surface etc. are readily available. Two models for illustrating the generation mechanism were examined: the FAC (flow accelerated corrosion) model and the macro-cell corrosion model. The latter explained the mechanism reasonably well, and methods for preventing wall thinning, based on this model, are given. Procedures for detecting the progress of wall thinning were also described. (author)

  5. 77 FR 21968 - Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe From the People's Republic of...

    Science.gov (United States)

    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...

  6. 75 FR 29972 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe from the People's...

    Science.gov (United States)

    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...

  7. 75 FR 6183 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe from the People's...

    Science.gov (United States)

    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,...

  8. 75 FR 57449 - Certain Seamless Carbon and Alloy Steel Standard, Line, and Pressure Pipe from the People's...

    Science.gov (United States)

    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)...

  9. 76 FR 7151 - Certain Carbon Steel Butt-Weld Pipe Fittings From Brazil, Japan, Taiwan, Thailand, and the People...

    Science.gov (United States)

    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...

  10. 75 FR 80455 - Certain Hot-Rolled Carbon Steel Flat Products From India: Amended Final Results of Countervailing...

    Science.gov (United States)

    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...

  11. 75 FR 59689 - Certain Hot-Rolled Carbon Steel Flat Products From India: Notice of Court Decision Not in Harmony...

    Science.gov (United States)

    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...

  12. 78 FR 15703 - Certain Hot-Rolled Carbon Steel Flat Products From India, Indonesia, the People's Republic of...

    Science.gov (United States)

    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...

  13. 75 FR 55742 - Certain Hot-Rolled Carbon Steel Flat Products from India: Extension of Time Limit for Preliminary...

    Science.gov (United States)

    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...

  14. 77 FR 14341 - Certain Hot-Rolled Carbon Steel Flat Products From Taiwan: Notice of Rescission of Antidumping...

    Science.gov (United States)

    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...

  15. 75 FR 81968 - Circular Welded Carbon Quality Steel Pipe From the People's Republic of China: Rescission of...

    Science.gov (United States)

    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...

  16. 78 FR 55057 - Corrosion-Resistant Carbon Steel Flat Products from the Republic of Korea: Preliminary Results of...

    Science.gov (United States)

    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...

  17. 75 FR 22555 - Certain Cut-to-Length Carbon-Quality Steel Plate from the Republic of Korea: Rescission of...

    Science.gov (United States)

    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...

  18. 77 FR 25404 - Certain Hot-Rolled Carbon Steel Flat Products From India: Rescission of Antidumping Duty...

    Science.gov (United States)

    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...

  19. 77 FR 36256 - Circular Welded Carbon-Quality Steel Pipe From India: Postponement of Final Determination of...

    Science.gov (United States)

    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...

  20. 76 FR 4291 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Partial Rescission of...

    Science.gov (United States)

    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...

  1. 77 FR 301 - Corrosion-Resistant Carbon Steel Flat Products From Germany and Korea: Institution of Five-Year...

    Science.gov (United States)

    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...

  2. 76 FR 77775 - Corrosion-Resistant Carbon Steel Flat Products from the Republic of Korea: Extension of Time...

    Science.gov (United States)

    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...

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

    International Nuclear Information System (INIS)

    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)

  4. 76 FR 19788 - Carbon Steel Butt-Weld Pipe Fittings From Brazil, China, Japan, Taiwan, and Thailand

    Science.gov (United States)

    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...

  5. 76 FR 57020 - Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Notice of Partial Rescission of...

    Science.gov (United States)

    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...

  6. 75 FR 3896 - Certain Welded Carbon Steel Pipe and Tube from Turkey: Extension of Time Limit for Preliminary...

    Science.gov (United States)

    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...

  7. 76 FR 71938 - Circular Welded Carbon Steel Pipes and Tubes From Thailand: Extension of Time Limit for...

    Science.gov (United States)

    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...

  8. 77 FR 41967 - Certain Circular Welded Carbon Steel Pipes and Tubes From India, Thailand, and Turkey; Certain...

    Science.gov (United States)

    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...

  9. 77 FR 32562 - Circular Welded Carbon-Quality Steel Pipe From India: Preliminary Determination of Sales at Less...

    Science.gov (United States)

    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,...

  10. 77 FR 2511 - Certain Welded Carbon Steel Pipe and Tube From Turkey: Extension of Time Limit for Preliminary...

    Science.gov (United States)

    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)....

  11. 76 FR 3083 - Certain Welded Carbon Steel Pipe and Tube From Turkey: Extension of Time Limit for Preliminary...

    Science.gov (United States)

    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)....

  12. 75 FR 63439 - Certain Welded Carbon Steel Standard Pipes and Tubes From India: Extension of the Final Results...

    Science.gov (United States)

    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...

  13. 77 FR 32508 - Circular Welded Carbon Steel Pipes and Tubes From Turkey: Notice of Preliminary Results of...

    Science.gov (United States)

    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...

  14. 76 FR 78313 - Circular Welded Carbon-Quality Steel Pipe From India, Oman, the United Arab Emirates, and Vietnam

    Science.gov (United States)

    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,...

  15. 76 FR 63902 - Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Final Results of Antidumping Duty...

    Science.gov (United States)

    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...

  16. 77 FR 6542 - Certain Welded Carbon Steel Standard Pipe and Tube From Turkey: Notice of Final Rescission of...

    Science.gov (United States)

    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...

  17. 77 FR 55807 - Circular Welded Carbon Steel Pipes and Tubes From Taiwan: Notice of Partial Rescission of...

    Science.gov (United States)

    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...

  18. 76 FR 78886 - Certain Welded Carbon Steel Standard Pipe and Tube From Turkey: Intent To Rescind Countervailing...

    Science.gov (United States)

    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...

  19. 75 FR 68327 - Certain Welded Carbon Steel Standard Pipes and Tubes From India: Rescission of Antidumping Duty...

    Science.gov (United States)

    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,...

  20. 75 FR 33262 - Certain Welded Carbon Steel Pipe and Tube from Turkey: Notice of Preliminary Results of...

    Science.gov (United States)

    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...