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Sample records for sendzimir steel works

  1. Basic survey for joint implementation, etc. Basic feasibility study on energy conservation at Tadeusz Sendzimir Steelworks

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    For the purpose of reducing greenhouse effect gas emissions, a feasibility study was conducted on the energy conservation at Huta Sendzimir Steelworks in Poland. The study was made on quantity-energy consuming facilities such as blast furnace, sintering plant and steelmaking plant, power plant, by-producing gas, purchased power, etc. Moreover, as to the energy consuming system, surveys were made on the exhaust heat recovery equipment already introduced and energy saving equipment for pig iron/steel making. As a result, it was found out that Huta Sendzimir Steelworks has an ability and experiences for implementation of the energy conservation project with no problems. As methods to save energy in individual production process, the introduction of the following was proposed: pressure recovery turbine of blast furnace, equipment for high temperature stove exhaust heat recovery, sintering cooler exhaust heat recovery, oxygen combustion furnace exhaust gas recovery, etc. By the introduction of these equipment, the reduction amount of greenhouse effect gas emissions per year will be approximately 180,000 ton-CO2. (NEDO)

  2. Refractories for steel-works

    International Nuclear Information System (INIS)

    Villanova, R.A.; Galant, C.L.; Haas, C.; Rosenbaum, V.

    The routine procedures utilized for quality control of refractory materials used by PIRATINI's steel-works, are presented ' under an objetive and practical maner. The attention of the paper is concentrated upon the following' refractory types with higher consume: silicon-aluminous; aluminous; basic magnesia; basic chrom-magnesia. All steps of utilization are described, including specification, supplies programation, storage; sampling; physical tests, and also aplication procedures. Results from routine analysis during a six month period, by ' means of X-Ray Quantometry, using the fusion pearls procedure, are presented compared with Atomic Absorption [pt

  3. Hardening of Fe-Cr-Mn steels cold plastic working

    International Nuclear Information System (INIS)

    Malinov, L.S.; Konop-Lyashko, V.I.; Nikoporets, N.M.

    1983-01-01

    The dependence is established between the level of proper-- ties obtained after cold plastic working and development of martensite transformations when loading in Fe-Cr-Mn steels containing 0.1-0.5% C, 13% Cr, 8-12% Mn, as well as in a number of complex alloyed steels. It is shown that the highest level of mechanical properties can be obtained after cold plastic working only in steels with definite austenite stability. Cold plastic working can both activize and stabilize austenite relatively to martensite formation during loading. The first thing is found when under the effect of preliminary cold working dislocation splitting takes place, as well as the formation of a small amount of E-phase and martensite. The second thing manifests itself when under the effect of cold working performed above Md (Md<20 deg C) cell dislocation structure is formed and dislocation pinning takes place

  4. Interaction model of steel ladle of continuous caster in steel works

    Directory of Open Access Journals (Sweden)

    Huang Bang Fu

    2016-01-01

    Full Text Available For further research on the precondition and interoperability model of interaction ladles among continuous caster, this article takes steel ladle of Y steel works as the object of research. On the basis of turnover number calculation model of single cast steel ladle, the relationship between cast number and the turnover number and turnover times and last turnover number are further analyzed. The simulation of steel ladle turnover rules was taken on the 2 continuous casters with Gantt chart. After that, the relationships between turnover number and last turnover number and non-turnover number are researched deeply. Combining with the Gantt chart, the expressions of start casting time and empty ladle ending time and heavy ladle starting time were put forward. The precondition of steel ladle interaction is obtained, which means the exchange ladle should not undertaking transport task in first stop continuous caster, and the empty ladle end time of exchange ladle of first stop continuous caster should early than the heavy ladle start time of last stop continuous caster. After applying the model to practice, 3 steel ladles of No.2 continuous caster can be reduced. This research results is supplying theoretical basis for steel ladle controlling and production organization optimization, and enriches the theory and method of metallurgical process integration.

  5. Analysis of the work-hardening process in spheroidized steels

    International Nuclear Information System (INIS)

    Pacheco, J.L.

    1981-07-01

    An elementary model for the work-hardening process in duplex-structures steels (ferrite - spheroidite) is proposed and tested on low, medium and high carbon content, which seems to give good results concerning the influence of the volume fraction and particle size of the second phase on the work-hardening behaviour. (Author) [pt

  6. Work-hardening of dual-phase steel

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, Florian

    2016-07-01

    Exhibiting good mechanical properties for cold-sheet forming, low-alloyed dual-phase (DP) steels are nowadays widely used for automotive applications. The composite-like microstructure of DP steels is composed of a low-carbon ductile ferrite-matrix and 10 - 60 vol.% hard martensitic inclusions. A nonlinear mean-field model and full-field finite-element simulations are applied to investigate three major topics: the influence of grain-size distribution, grain-level plasticity and derivation of an original material-model. The plastic behavior of polycrystals is assumed to be grain-size dependent in this work. The distribution of grain-sizes is taken to be lognormal. It is found that grain-size dispersion leads to a decrease of the material strength, in particular for small mean diameters around one micron. The numerical results from the mean-field model are confirmed notably well by means of a simple analytical expression. The micromechanical behavior of DP steels is investigated by full-field RVE simulations with a crystal-plasticity based ferrite-matrix and von Mises-type martensite inclusions. To examine the martensite influence, full-field simulation results of DP steels have been compared to an RVE in which martensite is substituted by ferrite. After quenching, a higher grain-boundary area covered by martensite facilitates an increased average dislocation-density. For uniaxial deformations above ∝10%, however, the grain-size dependent relation reverses. With more surrounding martensite, the local crystal-plasticity material-model exhibits hardening at a slower rate. A nonlinear mean-field model of Hashin-Shtrikman type is employed as framework for the original material-model for DP steels. The model incorporates the interaction of ferrite and martensite via incompatibility-induced long-range stresses in an averaged sense. The proposed model combines works of Ashby (1970) and Brown and Stobbs (1971a) to simulate the ferrite behavior. Based on the composite model

  7. IGSCC in cold worked austenitic stainless steel in BWR environment

    International Nuclear Information System (INIS)

    Persson, B.; Lindblad, B.

    1989-09-01

    The survey shows that austenitic stainless steels in a cold worked condition can exhibit IGSCC in BWR environment. It is also found that IGSCC often is initiated as a transgranular crack. Local stresses and surface defects very often acts as starting points for IGSCC. IGSCC due to cold working requires a cold working magnitude of at leas 5%. During cold working a formation of mechanical martensite can take place. The transgranular corrosion occurs in the martensitic phase due to sensitation. The crack propagates integranularly due to anodic solvation of α'-martensite. Sensitation of the martensitic phase is fasten in BCC-structures than in a FCC-structures mainly due to faster diffusion of chromium and carbon which cause precipitation of chromium carbides. Experiments show that a carbon content as low as 0.008% is enough for the formation of 68% martensite and for sensitation. Hydrogen induced cracking is regarded as a mechanism which can accelerate IGSCC. Such cracking requires a hydrostatic stress near the crack tip. Since the oxide in the crack tip is relatively impermeable to hydrogen, cracks in the oxide layer are required for such embrittlement. Hydrogen induced embrittlement of the martensitic phase, at the crack tip, can cause crack propagation. Solution heat treated unstabilized stainless steels are regarded to have a good resistance to IGSCC if they have not undergone cold working. In general, though, Mo-alloyed steels have a better resistance to IGSCC in BWR environment. Regarding the causes for IGSCC, the present literature survey shows that many mechanisms are suggested. To provide a safer ground for the estimation of crack propagation rates, SA recommends SKI to finance a project with the aim to determine the crack propagation rate on proper material. (authors) (65 refs.)

  8. Microstructure Evolution During Creep of Cold Worked Austenitic Stainless Steel

    Science.gov (United States)

    Krishan Yadav, Hari; Ballal, A. R.; Thawre, M. M.; Vijayanand, V. D.

    2018-04-01

    The 14Cr–15Ni austenitic stainless steel (SS) with additions of Ti, Si, and P has been developed for their superior creep strength and better resistance to void swelling during service as nuclear fuel clad and wrapper material. Cold working induces defects such as dislocations that interact with point defects generated by neutron irradiation and facilitates recombination to make the material more resistant to void swelling. In present investigation, creep properties of the SS in mill annealed condition (CW0) and 40 % cold worked (CW4) condition were studied. D9I stainless steel was solution treated at 1333 K for 30 minutes followed by cold rolling. Uniaxial creep tests were performed at 973 K for various stress levels ranging from 175-225 MPa. CW4 samples exhibited better creep resistance as compared to CW0 samples. During creep exposure, cold worked material exhibited phenomena of recovery and recrystallization wherein new strain free grains were observed with lesser dislocation network. In contrast CW0 samples showed no signs of recovery and recrystallization after creep exposure. Partial recrystallization on creep exposure led to higher drop in hardness in cold worked sample as compared to that in mill annealed sample. Accelerated precipitation of carbides at the grain boundaries was observed during creep exposure and this phenomenon was more pronounced in cold worked sample.

  9. The influence of cold work on the oxidation behaviour of stainless steel

    International Nuclear Information System (INIS)

    Langevoort, J.C.

    1985-01-01

    In this thesis the study of the interaction of oxygen gas with stainless steel surfaces is described. Thermogravimetry, microscopy and ellipsometry have been used to follow the oxidation in situ, while EDX, AES and XPS have been used to determine the oxide compositions. The aim of this thesis is to reveal the influence on the oxidation behaviour of stainless steel of i) cold work (rolling, drawing, milling, polishing and Ar ion bombardment) ii) the initially formed oxide and iii) the experimental conditions. Two types of stainless steels have been used (AISI 304 (a 18/8 Cr/Ni steel) and Incoloy 800 H (a 20/30 Cr/Ni steel)). (Auth.)

  10. [Relationship between shift work and overweight/obesity in male steel workers].

    Science.gov (United States)

    Xiao, M Y; Wang, Z Y; Fan, H M; Che, C L; Lu, Y; Cong, L X; Gao, X J; Liu, Y J; Yuan, J X; Li, X M; Hu, B; Chen, Y P

    2016-11-10

    Objective: To investigate the relationship between shift work and overweight/obesity in male steel workers. Methods: A questionnaire survey was conducted among the male steel workers selected during health examination in Tangshan Steel Company from March 2015 to March 2016. The relationship between shift work and overweight/obesity in the male steel workers were analyzed by using logistic regression model and restricted cubic splinemodel. Results: A total of 7 262 male steel workers were surveyed, the overall prevalence of overweight/obesitywas 64.5% (4 686/7 262), the overweight rate was 34.3% and the obesity rate was 30.2%, respectively. After adjusting for age, educational level and average family income level per month by multivariable logistic regression analysis, shift work was associated with overweight/obesity and obesity in the male steel workers. The OR was 1.19(95% CI : 1.05-1.35) and 1.15(95% CI : 1.00-1.32). Restricted cubic spline model analysis showed that the relationship between shift work years and overweight/obesity in the male steel workers was a nonlinear dose response one (nonlinear test χ 2 =7.43, P shift work years and obesity in the male steel workers was a nonlinear dose response one (nonlinear test χ 2 =10.48, P Shift work was associated with overweight and obesity in the male steel workers, and shift work years and overweight/obesity had a nonlinear relationship.

  11. Evaluation of the mechanical properties of Niobium modified cast AISI H 13 hot work tool steel

    International Nuclear Information System (INIS)

    Noorian, A.; Kheirandish, Sh.; Saghafian, H.

    2010-01-01

    In this research, the effects of partially replacing of vanadium and molybdenum with niobium on the mechanical properties of AISIH 13 hot-work tool steel have been studied. Cast samples made of the modified new steel were homogenized and austenitized at different conditions, followed by tempering at the specified temperature ranges. Hardness, red hardness, three point bending test and Charpy impact test were carried out to evaluate the mechanical properties together with characterizing the microstructure of the modified steel using scanning electron microscope. The results show that niobium addition modifies the cast structure of Nb-alloyed steel, and increases its maximum hardness. It was found that bending strength; bending strain, impact strength, and red hardness of the modified cast steel are also higher than those of the cast H13 steel, and lower than those of the wrought H13 steel.

  12. A comprehensive review on cold work of AISI D2 tool steel

    Science.gov (United States)

    Abdul Rahim, Mohd Aidil Shah bin; Minhat, Mohamad bin; Hussein, Nur Izan Syahriah Binti; Salleh, Mohd Shukor bin

    2017-11-01

    As a common material in mould and die application, AISI D2 cold work tool steel has proven to be a promising chosen material in the industries. However, challenges remain in using AISI D2 through a modified version with a considerable progress having been made in recent years. This paper provides a critical review of the original as-cast AISI D2 cold work tool steel up to the modified version. The main purpose is to develop an understanding of current modified tool steel trend; the machinability of AISI D2 (drilling, milling, turning, grinding and EDM/WEDM; and the microstructure evolution and mechanical properties of these cold work tool steels due to the presence of alloy materials in the steel matrix. The doping of rare earth alloy element, new steel fabrication processes, significant process parameter in machinability and surface treatment shows that there have been few empirical investigations into these cold work tool steel alloys. This study has discovered that cold work tool steel will remain to be explored in order to survive in the steel industries.

  13. Proceedings of the IEA Working Group meeting on ferritic/martensitic steels

    International Nuclear Information System (INIS)

    Klueh, R.L.

    1996-01-01

    An IEA working group on ferritic/martensitic steels for fusion applications, consisting of researchers from Japan, European Union, USA, and Switzerland, met at the headquarters of the Joint European Torus, Culham, UK. At the meeting, preliminary data generated on the large heats of steels purchased for the IEA program and on other heats of steels were presented and discussed. Second purpose of the meeting was to continue planning and coordinating the collaborative test program in progress on reduced-activation ferritic/martensitic steels. The majority of this report consists of viewographs for the presentations

  14. A low temperature aluminizing treatment of hot work tool steel

    Energy Technology Data Exchange (ETDEWEB)

    Matijevic, B., E-mail: bozidar.matijevic@fsb.hr [University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture, Zagreb (Croatia)

    2010-07-01

    Conventional aluminizing processes by pack cementation are typically carried out at elevated temperatures. A low temperature powder aluminizing technology was applied to hot tool steel H13. The aluminizing treating temperature was from 550 to 620°C. Effects of temperature and time on the microstructure and phase evolution were investigated. Also, the intermetallic layer thickness was measured in the aluminized layer of a steel substrate. The cross-sectional microstructures, the aluminized layer thickness and the oxide layer were studied. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), glow discharge optical spectroscopy (GDOS) were applied to observe the cross-sections and the distribution of elements. (author)

  15. A LOW TEMPERATURE ALUMINIZING TREATMENT OF HOT WORK TOOL STEEL

    OpenAIRE

    Matijević, Božidar

    2013-01-01

    Conventional aluminizing processes by pack cementation are typically carried out at elevated temperatures. A low temperature powder aluminizing technology was applied to the X40CrMoV5-1 hot tool steel. The aluminizing temperature was from 550 °C to 620 °C. Effects of temperature and time on the microstructure and phase evolution were investigated. Also, the intermetallic layer thickness was measured in the aluminized layer of a steel substrate. The cross-sectional microstructures, the alumini...

  16. A low temperature aluminizing treatment of hot work tool steel

    International Nuclear Information System (INIS)

    Matijevic, B.

    2010-01-01

    Conventional aluminizing processes by pack cementation are typically carried out at elevated temperatures. A low temperature powder aluminizing technology was applied to hot tool steel H13. The aluminizing treating temperature was from 550 to 620°C. Effects of temperature and time on the microstructure and phase evolution were investigated. Also, the intermetallic layer thickness was measured in the aluminized layer of a steel substrate. The cross-sectional microstructures, the aluminized layer thickness and the oxide layer were studied. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), glow discharge optical spectroscopy (GDOS) were applied to observe the cross-sections and the distribution of elements. (author)

  17. The hot working characteristics of a boron bearing and a conventional low carbon steel

    International Nuclear Information System (INIS)

    Stumpf, Waldo; Banks, Kevin

    2006-01-01

    Constitutive hot working constants were determined for an 11 ppm boron low carbon strip steel and compared from 875 to 1140 deg. C and strain rates of 0.001-2.5 s -1 to a high nitrogen low carbon strip steel. The boron steel showed a different hot working behaviour than the conventional steel with the steady state flow stress about 50-60% higher, the peak strain more than 50% higher and the eventual ferrite grain size about 40% smaller, if compared at the same temperature compensated strain rates or Z values. This difference persisted where the soaking temperature before compression was varied between 1140 and 1250 deg. C, proving that undissolved AlN in the boron-bearing steel was not responsible. With systematically varied linear cooling rates after hot working, the final ferrite grain size in the boron steel is finer and is independent of the two Z values applied during hot working. Retarded softening by dynamic recrystallisation during hot working in the boron containing steel is probably caused by boron solute drag of moving grain boundaries

  18. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang [KAIST, Daejon (Korea, Republic of)

    2015-12-15

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys.

  19. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    International Nuclear Information System (INIS)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang

    2015-01-01

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys

  20. Laser grooving of surface cracks on hot work tool steel

    Directory of Open Access Journals (Sweden)

    D. Klobčar

    2011-10-01

    Full Text Available The paper presents the analysis of laser grooving of 1.2343 tool steel hardened to 46 HRC. The effect of laser power and grooving speed on groove shape (i.e. depth and width, the material removal rate and the purity of produced groove as a measure of groove quality was investigated and analyzed using response surface methodology. Optimal parameters of laser grooving were found, which enables pure grooves suitable for laser welding.

  1. Work Hardening Behavior of 1020 Steel During Cold-Beating Simulation

    Science.gov (United States)

    CUI, Fengkui; LING, Yuanfei; XUE, Jinxue; LIU, Jia; LIU, Yuhui; LI, Yan

    2017-03-01

    The present research of cold-beating formation mainly focused on roller design and manufacture, kinematics, constitutive relation, metal flow law, thermo-mechanical coupling, surface micro-topography and microstructure evolution. However, the research on surface quality and performance of workpieces in the process of cold-beating is rare. Cold-beating simulation experiment of 1020 steel is conducted at room temperature and strain rates ranging from 2000 to 4000 s-1 base on the law of plastic forming. According to the experimental data, the model of strain hardening of 1020 steel is established, Scanning Electron Microscopy(SEM) is conducted, the mechanism of the work hardening of 1020 steel is clarified by analyzing microstructure variation of 1020 steel. It is found that the strain rate hardening effect of 1020 steel is stronger than the softening effect induced by increasing temperatures, the process of simulation cold-beating cause the grain shape of 1020 steel significant change and microstructure elongate significantly to form a fibrous tissue parallel to the direction of deformation, the higher strain rate, the more obvious grain refinement and the more hardening effect. Additionally, the change law of the work hardening rate is investigated, the relationship between dislocation density and strain, the relationship between work hardening rate and dislocation density is obtained. Results show that the change trend of the work hardening rate of 1020 steel is divided into two stages, the work hardening rate decreases dramatically in the first stage and slowly decreases in the second stage, finally tending toward zero. Dislocation density increases with increasing strain and strain rate, work hardening rate decreases with increasing dislocation density. The research results provide the basis for solving the problem of improving the surface quality and performance of workpieces under cold-beating formation of 1020 steel.

  2. Steel

    International Nuclear Information System (INIS)

    Zorev, N.N.; Astafiev, A.A.; Loboda, A.S.; Savukov, V.P.; Runov, A.E.; Belov, V.A.; Sobolev, J.V.; Sobolev, V.V.; Pavlov, N.M.; Paton, B.E.

    1977-01-01

    Steels also containing Al, N and arsenic, are suitable for the construction of large components for high-power nuclear reactors due to their good mechanical properties such as good through-hardening, sufficiently low brittleness conversion temperature and slight displacement of the latter with neutron irradiation. Defined steels and their properties are described. (IHOE) [de

  3. Applicability of Voce equation for tensile flow and work hardening behaviour of P92 ferritic steel

    International Nuclear Information System (INIS)

    Sainath, G.; Choudhary, B.K.; Christopher, J.; Isaac Samuel, E.; Mathew, M.D.

    2015-01-01

    Detailed analysis of true stress (σ)-true plastic strain (ε) data indicated that tensile flow behaviour of P92 ferritic steel can be adequately described by Voce equation at strain rates ranging from 3.16 × 10 −5 to 1.26 × 10 −3  s −1 over a temperature range 300–923 K. The steel exhibited two-stage work hardening in the variations of instantaneous work hardening rate (θ = dσ/dε) with stress. At all the strain rates, the variations in σ-ε, θ-σ and work hardening parameters associated with Voce equation with temperature exhibited three distinct temperature regimes. At intermediate temperatures, the variations in σ-ε, θ-σ and work hardening parameters with temperature and strain rate exhibited anomalous behaviour due to the occurrence of dynamic strain ageing in the steel. The shift in θ-σ towards low stresses, and rapid decrease in flow stress and work hardening parameters with increasing temperature and decreasing strain rate suggested dominance of dynamic recovery at high temperatures. - Highlights: • Tensile flow and work hardening behaviour of P92 steel has been examined. • Applicability of Voce equation to P92 steel is demonstrated. • Three temperature regimes in flow and work hardening has been observed. • Good match between predicted and the experimental tensile properties has been shown

  4. Influence of cold worked layer on susceptibility to stress corrosion of duplex stainless steel

    International Nuclear Information System (INIS)

    Labanowski, J.; Ossowska, A.; Cwiek, J.

    2001-01-01

    Stress corrosion cracking resistance of cold worked layers on duplex stainless steel was investigated. The surface layers were performed through burnishing treatment. Corrosion tests were performed with the use of Slow Strain Rate Test technique in boiling 35% MgCl 2 solution. It has been shown that burnishing treatment increases corrosion resistance of steel. The factor that improves stress corrosion cracking resistance is crack incubation time. (author)

  5. Investigation of Microstructure and Mechanical Properties in Hot-work Tool Steels

    OpenAIRE

    Rey, Tomas

    2017-01-01

    Hot-work tool steels make up an important group of steels that are able to perform with good strength and toughness properties at elevated temperatures and stresses. They are able to gain this behavior through their alloy composition and heat treatment, which relies on the precipitation of alloy carbides to counter the loss in strength as the tempered material becomes more ductile. As demand grows for materials that are suitable for even harsher applications and that show improved mechanical ...

  6. Laser Cladding of CPM Tool Steels on Hardened H13 Hot-Work Steel for Low-Cost High-Performance Automotive Tooling

    Science.gov (United States)

    Chen, J.; Xue, L.

    2012-06-01

    This paper summarizes our research on laser cladding of high-vanadium CPM® tool steels (3V, 9V, and 15V) onto the surfaces of low-cost hardened H13 hot-work tool steel to substantially enhance resistance against abrasive wear. The results provide great potential for fabricating high-performance automotive tooling (including molds and dies) at affordable cost. The microstructure and hardness development of the laser-clad tool steels so obtained are presented as well.

  7. Evaluation of dynamic fracture toughness of cold worked 9Cr-1Mo steel

    International Nuclear Information System (INIS)

    Sathyanarayanan, S.; Sasikala, G.; Ray, S.K.

    2004-01-01

    Dynamic J-R curves for cold worked 9Cr-1Mo steel have been estimated from instrumented impact test data at ambient temperature on pre-cracked Charpy specimens using three methods of analysis, namely those by Ray et al., Schindler, and Sreenivasan and Mannan. It is concluded that of these three, Schindler's method is the best suited for the purpose since it gives consistent variations with cold work of dynamic J-R curves and dynamic fracture toughness. Cold work results in substantial degradation in dynamic fracture toughness of 9Cr-1Mo steel

  8. Summary of the IEA workshop/working group meeting on ferritic/martensitic steels for fusion

    Energy Technology Data Exchange (ETDEWEB)

    Klueh, R.L. [Oak Ridge National Lab., TN (United States)

    1997-04-01

    An International Energy Agency (IEA) Working Group on Ferritic/Martensitic Steels for Fusion Applications, consisting of researchers from Japan, the European Union, the United States, and Switzerland, met at the headquarters of the Joint European Torus (JET), Culham, United Kingdom, 24-25 October 1996. At the meeting preliminary data generated on the large heats of steel purchased for the IEA program and on other heats of steels were presented and discussed. The second purpose of the meeting was to continue planning and coordinating the collaborative test program in progress on reduced-activation ferritic/martensitic steels. The next meeting will be held in conjunction with the International Conference on Fusion Reactor Materials (ICFRM-8) in Sendai, Japan, 23-31 October 1997.

  9. Summary of the IEA workshop/working group meeting on ferritic/martensitic steels for fusion

    International Nuclear Information System (INIS)

    Klueh, R.L.

    1997-01-01

    An International Energy Agency (IEA) Working Group on Ferritic/Martensitic Steels for Fusion Applications, consisting of researchers from Japan, the European Union, the United States, and Switzerland, met at the headquarters of the Joint European Torus (JET), Culham, United Kingdom, 24-25 October 1996. At the meeting preliminary data generated on the large heats of steel purchased for the IEA program and on other heats of steels were presented and discussed. The second purpose of the meeting was to continue planning and coordinating the collaborative test program in progress on reduced-activation ferritic/martensitic steels. The next meeting will be held in conjunction with the International Conference on Fusion Reactor Materials (ICFRM-8) in Sendai, Japan, 23-31 October 1997

  10. Hot working effect on austenite transformations in structural steel in continuous cooling

    International Nuclear Information System (INIS)

    Zajmovskij, V.A.; Kisteh, N.V.; Samedov, O.V.

    1979-01-01

    Austenite transformations in 40, 40Kh, 40KhN and 40KhNMA steels under hot working at 900 deg C with 20% reduction degree and continuous cooling with 1,7-16 0 /s are investigated. Changing of cooling rate in various ways affects the temperature range of austenite transformation in pearlite and bainite regions. Regulating the cooling rate after hot working one can essentially change the impact strength and steel ductility as a result of high temperature thermomechanical treatment effect

  11. Rapid nickel diffusion in cold-worked type 316 austenitic steel at 360-500 C

    Energy Technology Data Exchange (ETDEWEB)

    Arioka, Koji [Institute of Nuclear Safety Systems, Inc., Mihama (Japan); Iijima, Yoshiaki [Tohoku Univ., Sendai (Japan). Dept. of Materials Science; Miyamoto, Tomoki [Kobe Material Testing Laboratory Co. Ltd., Harima (Japan)

    2017-10-15

    The diffusion coefficient of nickel in cold-worked Type 316 austenitic steel was determined by the diffusion couple method in the temperature range between 360 and 500 C. A diffusion couple was prepared by electroless nickel plating on the surface of a 20 % cold-worked Type 316 austenitic steel specimen. The growth in width of the interdiffusion zone was proportional to the square root of diffusion time until 14 055 h. The diffusion coefficient of nickel (D{sub Ni}) in cold-worked Type 316 austenitic steel was determined by extrapolating the concentration-dependent interdiffusion coefficient to 11 at.% of nickel. The value of D{sub Ni} at 360 C was about 5 000 times higher than the lattice diffusion coefficient of nickel in Type 316 austenitic steel. The determined activation energy 117 kJ mol{sup -1} was 46.6 % of the activation energy 251 kJ mol{sup -1} for the lattice diffusion of nickel in Type 316 austenitic steel.

  12. Characterizing of steel used in the construction of civil works in Almeria

    International Nuclear Information System (INIS)

    Senobua, A. J.; Garzon, E.; Ayuso, J.; Perez, F.; Caballero, A.

    2003-01-01

    Various tests have been conducted on the steel bars used in the construction of civil works in Almeria (Spain) during the period 18 January 2000-7May 2001, with the aim of mechanically characterizing the different types of steel (weldable; B400S, B500S and ductile weldable: B400SD) to determine whether there is a technical reason for the increase in the use of ductile weldable steel. For this, we have used a hydraulic machine to break by traction all the test samples that arrived to the laboratory, following the specifications of the UNE 7474-1:1992 and the UNE 7474-2:1992. The results indicate that only in 86% of the cases does the steel B400SD satisfy the limits specified by the UNE 36065:1999-EX, as opposed to 95 and 94% of the B400S and B500S steels. In addition the ductile weldable steel registered mean values lower than those of B400S. This findings disagrees with expectations set by the specifications. (Author) 6 refs

  13. SCC susceptibility of cold-worked stainless steel with minor element additions

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Junichi, E-mail: nakano.junnichi@jaea.go.jp [Japan Atomic Energy Agency, Shirakatashirane 2-4, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195 (Japan); Nemoto, Yoshiyuki, E-mail: yoshiyuki.nemoto@oecd.org [OECD Nuclear Energy Agency, Le Seine St-Germain, 12, boulevard des Iles, F-92130 Issy-les-Moulineaux (France); Tsukada, Takashi, E-mail: tsukada.takashi@jaea.go.jp [Japan Atomic Energy Agency, Shirakatashirane 2-4, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195 (Japan); Uchimoto, Tetsuya, E-mail: uchimoto@ifs.tohoku.ac.jp [Tohoku University, Aoba-ku, Sendai-shi, Miyagi-ken 980-8577 (Japan)

    2011-10-01

    To examine the effects of minor elements on stress corrosion cracking (SCC) susceptibility of low carbon stainless steels with a work hardened layer, a high purity type 304 stainless steel was fabricated and minor elements, Si, S, P, C or Ti, were added. A work hardened layer was introduced by shaving on the surface of stainless steels. The specimens were exposed to a boiling 42% MgCl{sub 2} solution for 20 h and the number and the length of initiated cracks were examined. SCC susceptibility of the specimen with P was the highest and that of the specimen with C was the lowest in all specimens. By magnetic force microscope examination, a magnetic phase expected to be a martensitic phase was detected near the surface. Since corrosion resistance of martensite is lower than that of austenite, the minor elements additions would affect SCC susceptibility through the amount of the transformed martensite.

  14. SCC susceptibility of cold-worked stainless steel with minor element additions

    International Nuclear Information System (INIS)

    Nakano, Junichi; Nemoto, Yoshiyuki; Tsukada, Takashi; Uchimoto, Tetsuya

    2011-01-01

    To examine the effects of minor elements on stress corrosion cracking (SCC) susceptibility of low carbon stainless steels with a work hardened layer, a high purity type 304 stainless steel was fabricated and minor elements, Si, S, P, C or Ti, were added. A work hardened layer was introduced by shaving on the surface of stainless steels. The specimens were exposed to a boiling 42% MgCl 2 solution for 20 h and the number and the length of initiated cracks were examined. SCC susceptibility of the specimen with P was the highest and that of the specimen with C was the lowest in all specimens. By magnetic force microscope examination, a magnetic phase expected to be a martensitic phase was detected near the surface. Since corrosion resistance of martensite is lower than that of austenite, the minor elements additions would affect SCC susceptibility through the amount of the transformed martensite.

  15. Prediction of ttt curves of cold working tool steels using support vector machine model

    Science.gov (United States)

    Pillai, Nandakumar; Karthikeyan, R., Dr.

    2018-04-01

    The cold working tool steels are of high carbon steels with metallic alloy additions which impart higher hardenability, abrasion resistance and less distortion in quenching. The microstructure changes occurring in tool steel during heat treatment is of very much importance as the final properties of the steel depends upon these changes occurred during the process. In order to obtain the desired performance the alloy constituents and its ratio plays a vital role as the steel transformation itself is complex in nature and depends very much upon the time and temperature. The proper treatment can deliver satisfactory results, at the same time process deviation can completely spoil the results. So knowing time temperature transformation (TTT) of phases is very critical which varies for each type depending upon its constituents and proportion range. To obtain adequate post heat treatment properties the percentage of retained austenite should be lower and metallic carbides obtained should be fine in nature. Support vector machine is a computational model which can learn from the observed data and use these to predict or solve using mathematical model. Back propagation feedback network will be created and trained for further solutions. The points on the TTT curve for the known transformations curves are used to plot the curves for different materials. These data will be trained to predict TTT curves for other steels having similar alloying constituents but with different proportion range. The proposed methodology can be used for prediction of TTT curves for cold working steels and can be used for prediction of phases for different heat treatment methods.

  16. A temperature dependent cyclic plasticity model for hot work tool steel including particle coarsening

    Science.gov (United States)

    Jilg, Andreas; Seifert, Thomas

    2018-05-01

    Hot work tools are subjected to complex thermal and mechanical loads during hot forming processes. Locally, the stresses can exceed the material's yield strength in highly loaded areas as e.g. in small radii in die cavities. To sustain the high loads, the hot forming tools are typically made of martensitic hot work steels. While temperatures for annealing of the tool steels usually lie in the range between 400 and 600 °C, the steels may experience even higher temperatures during hot forming, resulting in softening of the material due to coarsening of strengthening particles. In this paper, a temperature dependent cyclic plasticity model for the martensitic hot work tool steel 1.2367 (X38CrMoV5-3) is presented that includes softening due to particle coarsening and that can be applied in finite-element calculations to assess the effect of softening on the thermomechanical fatigue life of hot work tools. To this end, a kinetic model for the evolution of the mean size of secondary carbides based on Ostwald ripening is coupled with a cyclic plasticity model with kinematic hardening. Mechanism-based relations are developed to describe the dependency of the mechanical properties on carbide size and temperature. The material properties of the mechanical and kinetic model are determined on the basis of tempering hardness curves as well as monotonic and cyclic tests.

  17. Effect of cold work on tensile behavior of irradiated type 316 stainless steel

    International Nuclear Information System (INIS)

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

    1986-01-01

    Tensile specimens were irradiated in ORR at 250, 290, 450, and 500 0 C to produce a displacement damage of approx.5 dpa and 40 at. ppM He. Irradiation at 250 and 290 0 C caused an increase in yield stress and ultimate tensile strength and a decrease in ductility relative to unaged and thermally aged controls. The changes were greatest for the 20%-cold-worked steel and lowest for the 50%-cold-worked steel. Irradiation at 450 0 C caused a slight relative decrease in strength for all cold-worked conditions. A large decrease was observed at 500 0 C, with the largest decrease occurring for the 50%-cold-worked specimen. No bubble, void, or precipitate formation was observed for specimens examined by transmission electron microscopy (TEM). The irradiation hardening was correlated with Frank-loop and ''black-dot'' loop damage. A strength decrease at 500 0 C was correlated with dislocation network recovery. Comparison of tensile and TEM results from ORR-irradiated steel with those from steels irradiated in the High Flux Isotope Reactor and the Experimental Breeder Reactor indicated consistent strength and microstructure changes

  18. Effect of cold working on nitriding process of AISI 304 and 316 austenitic stainless steel

    International Nuclear Information System (INIS)

    Pereira, Silvio Andre de Lima

    2012-01-01

    The nitriding behavior of AISI 304 and 316 austenitic stainless steel was studied by different cold work degree before nitriding processes. The microstructure, thickness, microhardness and chemical micro-composition were evaluated through optical microscopy, microhardness, scanner electronic microscopy and x ray diffraction techniques. Through them, it was observed that previous plastic deformations do not have influence on layer thickness. However, a nitrided layer thicker can be noticed in the AISI 304 steel. In addition, two different layers can be identified as resulted of the nitriding, composed for austenitic matrix expanded by nitrogen atoms and another thinner immediately below expanded by Carbon atoms. (author)

  19. A Study on the Characteristics of Corrosion in Cold Worked Flexible STS 304 Stainless Steel Pipes

    International Nuclear Information System (INIS)

    Kim, In Soo; Kim, Sung Jin

    1993-01-01

    Effects of cold working on the corrosion resistance of austenitic STS 304 stainless steel pipes were investigated using anodic polarization method, EDX analysis and SEM technique. Corrosion products had a lots of S and Cl - ion. Generally, corrosion patterns as a result of STS 304 stainless steel to concrete environment were proceeded in the order of the pitting to intergranular corrosion. In the case of the flexible pipes were covered tightly with other polymer materials, crevice corrosion occurred to a much greater extent on austenitic than on martensitic region

  20. Research on working property and early age mechanical property of self-compacting concrete used in steel-concrete structure

    International Nuclear Information System (INIS)

    Zhao Yongguang

    2013-01-01

    Background: Self-compacting concrete that has good working property is the prerequisite of steel-concrete structure. The early age mechanical property of self-compacting concrete is the important parameter when design steel-concrete structure. Purpose: This paper attempts to research the working property and early age mechanical property of self-compacting concrete. Methods: Test is used to research the working property and early age mechanical property of self-compacting concrete. Results: Self-compacting concrete that could meet the requirement of steel-concrete structure has been mixed and parameters of early age mechanical property of self-compacting concrete which is necessary for design of steel-concrete structure have been presented. Conclusions: Base on the results, this paper can guide the construction of self-compacting concrete in steel-concrete structure and the design and construction of steel-concrete structure. (author)

  1. Surface enhancement of cold work tool steels by friction stir processing with a pinless tool

    Science.gov (United States)

    Costa, M. I.; Verdera, D.; Vieira, M. T.; Rodrigues, D. M.

    2014-03-01

    The microstructure and mechanical properties of enhanced tool steel (AISI D2) surfaces produced using a friction stir welding (FSW) related procedure, called friction stir processing (FSP), are analysed in this work. The surface of the tool steel samples was processed using a WC-Co pinless tool and varying processing conditions. Microstructural analysis revealed that meanwhile the original substrate structure consisted of a heterogeneous distribution of coarse carbides in a ferritic matrix, the transformed surfaces consisted of very small carbides, homogenously distributed in a ferrite- bainite- martensite matrix. The morphology of the surfaces, as well as its mechanical properties, evaluated by hardness and tensile testing, were found to vary with increasing tool rotation speed. Surface hardness was drastically increased, relative to the initial hardness of bulk steel. This was attributed to ferrite and carbide refinement, as well as to martensite formation during solid state processing. At the highest rotation rates, tool sliding during processing deeply compromised the characteristics of the processed surfaces.

  2. Microstructural evolution of a cold work tool steel after pulsed laser remelting

    Directory of Open Access Journals (Sweden)

    L. Kosec

    2012-01-01

    Full Text Available The aim of this study is the investigation of micro-structural behaviour of a Mat. No. 1.2379 (EN-X160CrMoV121; AISI D2 cold work tool steel after remelting with a precise pulsed Nd:YAG laser. The investigated steel is one of the most hard to weld tool steels, due to large amount of alloying elements. The analysis was done on single spots remelted with specific laser pulse shape and parameters, assuring crack-less solidification. Re-solidifi ed areas were investigated with microscopy, hardness measurements, X-ray spectroscopy and diffraction method. Laser treatment causes rapid solidifi cation leading into a formation of a fine dendritic microstructures containing high amount of retained austenite causing a significant decrease of hardness.

  3. Unit rupture work as a criterion for quantitative estimation of hardenability in steel

    International Nuclear Information System (INIS)

    Kramarov, M.A.; Orlov, E.D.; Rybakov, A.B.

    1980-01-01

    Shown is possible utilization of high sensitivity of resistance to fracture of structural steel to the hardenability degree in the course of hardening to find the quantitative estimation of the latter one. Proposed is a criterion kappa, the ratio of the unit rupture work in the case of incomplete hardenability (asub(Tsub(ih))) under investigation, and the analoguc value obtained in the case of complete hardenability Asub(Tsub(Ch)) at the testing temperature corresponding to the critical temperature Tsub(100(M). Confirmed is high criterion sensitivity of the hardened steel structure on the basis of experimental investigation of the 40Kh, 38KhNM and 38KhNMFA steels after isothermal hold-up at different temperatures, corresponding to production of various products of austenite decomposition

  4. EDF program on SCC initiation of cold-worked stainless steels in primary water

    Energy Technology Data Exchange (ETDEWEB)

    Huguenin, P.; Vaillant, F.; Couvant, T. [Electricite de France (EDF/RD), Site des Renardieres, 77 - Moret sur loing (France); Buisse, L. [EDF UTO, 93 - Noisy-Le-Grand (France); Huguenin, P.; Crepin, J.; Duhamel, C.; Proudhon, H. [MINES ParisTech, Centre des Materiaux, 91 - Evry (France); Ilevbare, G. [EPRI California (United States)

    2009-07-01

    A few cases of Intergranular Stress Corrosion Cracking (IGSCC) on cold-worked austenitic stainless steels in primary water have been detected in French Pressurized Water Reactors (PWRs). A previous program launched in the early 2000's identified the required conditions for SCC of cold-worked stainless steels. It was found that a high strain hardening coupled with cyclic loading favoured SCC, whereas cracking under static conditions appeared to be difficult. A propagation model was also proposed. The first available results of the present study demonstrate the strong influence of a trapezoidal cyclic loading on the creep of 304L austenitic stainless steel. While no creep was detected under a pure static loading, the creep rate was increased by a factor 102 under a trapezoidal cyclic loading. The first results of SCC initiation performed on notched specimens under a trapezoidal cyclic loading at low frequency are presented. The present study aims at developing an engineering model for IGSCC initiation of 304L, 316L and weld 308L stainless steels. The effect of the pre-straining on the SCC mechanisms is more specifically studied. Such a model will be based on (i) SCC initiation tests on notched and smooth specimens under 'trapezoidal' cyclic loading and, (ii) constant strain rate SCC initiation tests. The influence of stress level, cold-work level, strain path, surface roughness and temperature is particularly investigated. (authors)

  5. Evaluation of essential work of fracture in a dual phase high strength steel sheet

    International Nuclear Information System (INIS)

    Gutierrez, D.; Perez, L. I.; Lara, A.; Casellas, D.; Prado, J. M.

    2013-01-01

    Fracture toughness of advanced high strength steels (AHSS), can be used to optimize crash behavior of structural components. However it cannot be readily measured in metal sheet because of the sheet thickness. In this work, the Essential Work of Fracture (EWF) methodology is proposed to evaluate the fracture toughness of metal sheets. It has been successfully applied in polymers films and some metal sheets. However, their information about the applicability of this methodology to AHSS is relatively scarce. In the present work the fracture toughness of a Dual Phase (strength of 800 MPa) and drawing steel sheets has been measured by means of the EWF. The results show that the test requirements are met and also show the clear influence of notch radii on the measured values, specially for the AHSS grade. Thus, the EWF is postulated as a methodology to evaluate the fracture toughness in AHSS sheets. (Author) 18 refs.

  6. Effect of cold working and annealing on stress corrosion cracking of AISI 304 stainless steel

    International Nuclear Information System (INIS)

    Yeon, Y.M.; Kwun, S.I.

    1983-01-01

    A study was made of the effects of cold working and annealing on the stress corrosion cracking of AISI 304 stainless steel in boiling 42% MgCl 2 solution. When the 60% or 76% of yield stress was applied, the resistance to SCC showed maximum at 30% of cold work. However, when the same load was applied to the annealed specimens after cold working, the resistance to SCC decreased abruptly at 675degC annealing. The fracture mode changed mode change mixed → intergranular → transgranular as the amount of cold work increased. (Author)

  7. Microscopic work function anisotropy and surface chemistry of 316L stainless steel using photoelectron emission microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, N., E-mail: nick.barrett@cea.fr [CEA, IRAMIS, SPEC, LENSIS, F-91191 Gif-sur-Yvette (France); Renault, O. [CEA, LETI, Minatec Campus, F-38054 Grenoble Cedex 09 (France); Lemaître, H. [Université de Cergy-Pontoise, Rue d’Eragny, Neuville sur Oise, 95 031 Cergy-Pontoise (France); Surface Dynamics Laboratory, Institut for Fysik og Astronomi Aarhus Universitet, Ny Munkegade 120, 8000 Aarhus C (Denmark); Bonnaillie, P. [CEA, DEN, DANS, DMN, SRMP, F-91191 Gif-sur-Yvette (France); Barcelo, F. [CEA, DEN, DANS, DMN, SRMA, LA2M, F-91191 Gif-sur-Yvette (France); Miserque, F. [CEA, DEN, DANS, DPC, SCCME, LECA, F-91191 Gif-sur-Yvette (France); Wang, M.; Corbel, C. [Laboratoire des Solides Irradis, Ecole Polytechnique, route de Saclay, F-91128 Palaiseau (France)

    2014-08-15

    Highlights: • PEEM and EBSD study of spatial variations in local work function of 316L steel. • Correlation between work function and crystal grain orientation at the surface of 316L steel. • Spatially resolved chemistry of residual oxide layer. - Abstract: We have studied the variation in the work function of the surface of sputtered cleaned 316L stainless steel with only a very thin residual oxide surface layer as a function of grain orientation using X-ray photoelectron emission microscopy (XPEEM) and Electron Backscattering Diffraction. The grains are mainly oriented [1 1 1] and [1 0 1]. Four distinct work function values spanning a 150 meV energy window are measured. Grains oriented [1 1 1] have a higher work function than those oriented [1 0 1]. From core level XPEEM we deduce that all grain surfaces are Cr enriched and Ni depleted whereas the Cr/Fe ratio is similar for all grains. The [1 1 1] oriented grains show evidence for a Cr{sub 2}O{sub 3} surface oxide and a higher concentration of defective oxygen sites.

  8. In-situ neutron diffraction study on work-hardening behavior in a ferrite-martensite dual phase steel

    OpenAIRE

    Morooka, Satoshi; Sato, Naoko; Ojima, Mayumi; Harjo, Stefanus; Adachi, Yoshitaka; Tomota, Yo; Umezawa, Osamu

    2011-01-01

    Strength and work-hardening in steels have been discussed from the viewpoint of heterogeneous deformation. In-situ neutron diffraction techniques made clear that the misfit strains between grains accompanied with the grain-scaled internal stress (intergranular stress). In the dual phase steel, the intergranular stress was superposed on phase stress. Both long-range internal stress and short-range one like forest dislocation hardening may cause the resistance for dislocation motion in the steels.

  9. Heat Treatment Optimization and Properties Correlation for H11-Type Hot-Work Tool Steel

    Science.gov (United States)

    Podgornik, B.; Puš, G.; Žužek, B.; Leskovšek, V.; Godec, M.

    2018-02-01

    The aim of this research was to determine the effect of vacuum-heat-treatment process parameters on the material properties and their correlations for low-Si-content AISI H11-type hot-work tool steel using a single Circumferentially Notched and fatigue Pre-cracked Tensile Bar (CNPTB) test specimen. The work was also focused on the potential of the proposed approach for designing advanced tempering diagrams and optimizing the vacuum heat treatment and design of forming tools. The results show that the CNPTB specimen allows a simultaneous determination and correlation of multiple properties for hot-work tool steels, with the compression and bending strength both increasing with hardness, and the strain-hardening exponent and bending strain increasing with the fracture toughness. On the other hand, the best machinability and surface quality of the hardened hot-work tool steel are obtained for hardness values between 46 and 50 HRC and a fracture toughness below 60 MPa√m.

  10. SCC growth behavior of cast stainless steels in high-temperature water. Influences of corrosion potential, steel type, thermal aging and cold-work

    International Nuclear Information System (INIS)

    Yamada, Takuyo; Terachi, Takumi; Miyamoto, Tomoki; Arioka, Koji

    2011-01-01

    Recent studies on crack growth rate (CGR) measurement in oxygenated high-temperature pure water conditions, such as normal water chemistry (NWC) in BWRs, using compact tension (CT) type specimens have shown that stainless steel weld metal are susceptible to stress corrosion cracking (SCC). On the other hand, the authors reported that no significant SCC growth was observed on stainless steel weld metals in PWR primary water at temperatures from 250degC to 340degC. Cast austenitic stainless steels are widely used in light water reactors, and there is a similarity between welded and cast stainless steels in terms of the microstructure of the ferrite/austenite duplex structure. However, there are a few reports giving CGR data on cast stainless steels in the BWRs and PWRs. The principal purpose of this study was to examine the SCC growth behavior of cast stainless steels in simulated PWR primary water. A second objective was to examine the effects on SCC growth in hydrogenated and oxygenated water environments at 320degC of: (1) corrosion potential; (2) steels type (Mo in alloy); (3) thermal-aging (up to 400degC x 40 kh); and (4) cold-working (10%). The results were as follows: (1) No significant SCC growth was observed on all types of cast stainless steels: aged (400degC x 40 kh) of SCS14A and SCS13A and 10% cold-working, in hydrogenated (low-potential) water at 320degC. (2) Aging at 400degC x 40 kh SCS14A (10%CW) markedly accelerated the SCC growth of cast material in high-potential water at 320degC, but no significant SCC growth was observed in the hydrogenated water, even after long-term thermal aging (400degC x 40 kh). (3) Thus, cast stainless steels have excellent SCC resistance in PWR primary water. (4) On the other hand, significant SCC growth was observed on all types of cast stainless steels: 10%CW SCS14A and SCS13A, in 8 ppm-oxygenated (high-potential) water at 320degC. (5) No large difference in SCC growth was observed between SCS14A (Mo) and SCS13A. (6) No

  11. Thermal creep and stress-affected precipitation of 20% cold-worked 316 stainless steel

    International Nuclear Information System (INIS)

    Puigh, R.J.; Lovell, A.J.; Garner, F.A.

    1984-01-01

    Measurements of the thermal creep of 20% cold-worked 316 stainless steel have been performed for temperatures from 593 to 760 0 C, stress levels as high as 138 MPa and exposure times as long as 15,000 hours. The creep strains exhibit a complex behavior arising from the combined action of true creep and stress-affected precipitation of intermetallic phases. The latter process is suspected to be altered by neutron irradiation. (orig.)

  12. Metal Dust Exposure and Respiratory Health of Male Steel Work¬ers in Terengganu, Malaysia

    OpenAIRE

    Nurul Ainun HAMZAH; Shamsul Bahri MOHD TAMRIN; Noor Hassim ISMAIL

    2015-01-01

    Background: This cross sectional study was carried out to determine the relationship between metal dust exposure and respiratory health in male steel workers in Terengganu, Malaysia.Methods: Subjects were interviewed using a structured questionnaire from British Medical Research Council (BMRC) Questionnaire regarding respiratory symptoms and were examined their lung function using spirometer.Results: The mean trace metal dusts concentration TWA8 for cobalt and chromium in most of work unit ex...

  13. Welding of cold worked austenitic steels - comparison of TIG, EB and laser processes

    International Nuclear Information System (INIS)

    Richard, A.; Prunele, D. de; Castilan, F.

    1993-01-01

    Effect of welding on cold worked components is a local falling of their properties. Modifications induced by such an operation depend on the thermal cycle and consequently on the welding process. An experimental study aim of which is to compare respective effects of different welding processes (TIG, EB, laser) has been realized. This publication presents results related to 316L and 316Ti steels. (author). 2 refs., 7 figs., 1 tab

  14. Rapid nickel diffusion in cold-worked carbon steel at 320-450 °C

    Science.gov (United States)

    Arioka, Koji; Iijima, Yoshiaki; Miyamoto, Tomoki

    2015-11-01

    The diffusion coefficient of nickel in cold-worked carbon steel was determined with the diffusion couple method in the temperature range between 320 and 450 °C. Diffusion couple was prepared by electro-less nickel plating on the surface of a 20% cold-worked carbon steel. The growth in width of the interdiffusion zone was proportional to the square root of diffusion time to 12,000 h. The diffusion coefficient (DNi) of nickel in cold-worked carbon steel was determined by extrapolating the concentration-dependent interdiffusion coefficient to 0% of nickel. The temperature dependence of DNi is expressed by DNi = (4.5 + 5.7/-2.5) × 10-11 exp (-146 ± 4 kJ mol-1/RT) m2s-1. The value of DNi at 320 °C is four orders of magnitude higher than the lattice diffusion coefficient of nickel in iron. The activation energy 146 kJ mol-1 is 54% of the activation energy 270.4 kJ mol-1 for lattice diffusion of nickel in the ferromagnetic state iron.

  15. Microstructural study and densification analysis of hot work tool steel matrix composites reinforced with TiB{sub 2} particles

    Energy Technology Data Exchange (ETDEWEB)

    Fedrizzi, A., E-mail: anna.fedrizzi@ing.unitn.it [Department of Industrial Engineering, University of Trento, Via Mesiano 77, 38123 Trento (Italy); Pellizzari, M. [Department of Industrial Engineering, University of Trento, Via Mesiano 77, 38123 Trento (Italy); Zadra, M. [K4Sint, Start-up of the University of Trento, Viale Dante 300, 38057 Pergine Valsugana (Italy); Marin, E. [Department of Chemistry, Physics and Environment, University of Udine, Via Cotonificio 108, 33100 Udine (Italy)

    2013-12-15

    Hot work tool steels are characterized by good toughness and high hot hardness but are less wear resistant than other tooling materials, such as high speed steel. Metal matrix composites show improved tribological behavior, but not much work has been done in the field of hot work tool steels. In this paper TiB{sub 2}-reinforced hot work tool steel matrix composites were produced by spark plasma sintering (SPS). Mechanical alloying (MA) was proposed as a suited process to improve the composite microstructure. Density measurements and microstructure confirmed that MA promotes sintering and produces a fine and homogeneous dispersion of reinforcing particles. X-ray diffraction patterns of the sintered composites highlighted the formation of equilibrium Fe{sub 2}B and TiC, as predicted by thermodynamic calculations using Thermo-Calc® software. Scanning electron microscopy as well as scanning Kelvin probe force microscopy highlighted the reaction of the steel matrix with TiB{sub 2} particles, showing the formation of a reaction layer at the TiB{sub 2}-steel interface. Phase investigations pointed out that TiB{sub 2} is not chemically stable in steel matrix because of the presence of carbon even during short time SPS. - Highlights: • TiB{sub 2} reinforced steel matrix composites were produced by spark plasma sintering. • TiB{sub 2} was successfully dispersed in the steel matrix by mechanical alloying. • Steel and TiB{sub 2} react during sintering forming equilibrium Fe{sub 2}B and TiC. • The new phases were investigated by means of AFM, Volta potential and XRD analyses.

  16. Effects of thermomechanical processing on microstructure and properties of bainitic work hardening steel

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Jie, E-mail: caojie910@ahut.edu.cn [School of Metallurgical Engineering, Anhui University of Technology, Ma’anshan 243002 (China); Yan, Jun; Zhang, Jing [School of Metallurgical Engineering, Anhui University of Technology, Ma’anshan 243002 (China); Yu, Tongren [Technology Center, Maanshan Iron & Steel Company Limited, Ma’anshan 243000 (China)

    2015-07-15

    The thermomechanical processing (TMP) of a bainitic work hardening steel was carried out on a Gleeble3500 simulator. The microstructure of processed specimens was investigated by means of optical and electron microscopy, and tensile tests were performed in a ZwickRoell tensile tester. The deformation temperatures of austenite varied from 800 °C to 900 °C. The cooling methods include single rate cooling method and two-stage cooling method. The two-stage cooling method includes fast cooling rates ranging from 4 °C/s to 12 °C/s and slow cooling rates ranging from 1 °C/s to 2 °C/s. It is shown that, within the range of parameters tested, the obtained microstructures are granular bainite, the tensile strength of the steel can be adjusted from 897.8 MPa to 1083.2 MPa, and good plasticity can be obtained at different strength levels.

  17. Determining Ms temperature on a AISI D2 cold work tool steel using magnetic Barkhausen noise

    Energy Technology Data Exchange (ETDEWEB)

    Huallpa, Edgar Apaza, E-mail: gared1@gmail.com [Escola Politécnica da Universidade de São Paulo, Av. Prof. Mello Moraes 2463, 05508-030 SP (Brazil); Sánchez, J. Capó, E-mail: jcapo@usp.br [Departamento de Física, Facultad de Ciencias Naturales, Universidad de Oriente, Av. Patricio Lumumba s/n 90500, Santiago de Cuba (Cuba); Padovese, L.R., E-mail: lrpadove@usp.br [Escola Politécnica da Universidade de São Paulo, Av. Prof. Mello Moraes 2463, 05508-030 SP (Brazil); Goldenstein, Hélio, E-mail: hgoldens@usp.br [Escola Politécnica da Universidade de São Paulo, Av. Prof. Mello Moraes 2463, 05508-030 SP (Brazil)

    2013-11-15

    Highlights: ► MBN was used to follow the martensite transformation in a tool steel. ► The results were compared with resistivity experiments. ► The Ms was estimated with Andrews equation coupled to ThermoCalc calculations. The experimental results showed good agreement. -- Abstract: The use of Magnetic Barkhausen Noise (MBN) as a experimental method for measuring the martensite start (Ms) temperature was explored, using as model system a cold-work tool steel (AISI D2) austenitized at a very high temperature (1473 K), so as to transform in sub-zero temperatures. The progress of the transformation was also followed with electrical resistance measurements, optical microscopy and scanning electron microscopy. Both MBN and resistivity measurements showed a change near 230 K during cooling, corresponding to the Ms temperature, as compared with 245 K, estimated with Andrews empirical equation applied to the austenite composition calculated using ThermoCalc.

  18. The effect of boriding on wear resistance of cold work tool steel

    International Nuclear Information System (INIS)

    Anzawa, Y; Koyama, S; Shohji, I

    2017-01-01

    Recently, boriding has attracted extensive attention as surface stiffening processing of plain steel. In this research, the influence of processing time on the formation layer of cold work tool steel (KD11MAX) by Al added fused salt bath was examined. In addition, in order to improve the abrasion resistance of KD11MAX, the effect of the treatment of boronization on the formation layer has been investigated. Boriding were performed in molten borax which contained about 10 mass% Al at processing time of 1.8 ∼ 7.2 ks (processing temperature of 1303 K). As a result of the examination, the hardness of the boriding layer becomes about 1900 HV when the processing time of 3.6 ks. Also the abrasion resistance has improved remarkably. Furthermore, it was revealed that the formation layer was boronized iron from the Vickers hardness and analysis of the X-ray diffraction measurement. (paper)

  19. DIFFICULTIES IN WORK SAFETY MANAGEMENT IN A COMPANY PRODUCING STEEL FLAT BARS

    Directory of Open Access Journals (Sweden)

    Marta Niciejewska

    2018-01-01

    Full Text Available According to research, metal processing industry has the highest risk of accidents at work, due to the necessity for personal protective equipment use and strict execution of safety rules and procedures. The paper presents the individual characteristics of health and safety management in the company producing steel flat bars. Special attention has been paid to the safety aspect of the use of automated logistical equipment (gantries, automatics that increase the risk of work-related accidents. The results of research on the difficulties resulting from the specifics of production (metallurgical industry has been presented.

  20. Creep rupture properties of solution annealed and cold worked type 316 stainless steel cladding tubes

    International Nuclear Information System (INIS)

    Mathew, M.D.; Latha, S.; Mannan, S.L.; Rodriguez, P.

    1990-01-01

    Austenitic stainless steels (mainly type 316 and its modifications) are used as fuel cladding materials in all current generation fast breeder reactors. For the Fast Breeder Test Reactor (FBTR) at Kalpakkam, modified type 316 stainless steel (SS) was chosen as the material for fuel cladding tubes. In order to evaluate the influence of cold work on the performance of the fuel element, the investigation was carried out on cladding tubes in three metallurgical conditions (solution annealed, ten percent cold worked and twenty percent cold worked). The results indicate that: (i) The creep strength of type 316 SS cladding tube increases with increasing cold work. (ii) The benificial effects of cold work are retained at almost all the test conditions investigated. (iii) The Larson Miller parameter analysis shows a two slope behaviour for 20PCW material suggesting that caution should be exercised in extrapolating the creep rupture life to stresses below 125 MPa. At very low stress levels, the LMP values fall below the values of the 10 PCW material. (author). 6 refs., 19 figs. , 10 tabs

  1. EBSD study of purity effects during hot working in austenitic stainless steels

    International Nuclear Information System (INIS)

    El Wahabi, M.; Gavard, L.; Cabrera, J.M.; Prado, J.M.; Montheillet, F.

    2005-01-01

    The technique of electron back scattering diffraction (EBSD) is considered as a powerful instrument for the study of the microstructural changes during hot forming processes and gives the possibility to present the information in different ways (OIM, misorientation diagram and pole figures). The present work is focused on the observation by EBSD of the microstructure evolution during deformation at high temperature of three austenitic stainless steels: AISI-304H, AISI-304L and a high purity steel HP. The difference between the three steels is the content carbon and the presence of residual elements. To this aim compression tests were carried out at a constant strain rate of 0.001 s -1 and different temperatures. The study showed an increase of twin boundary fractions and a diminution of substructure (low angle densities boundaries) at increasing temperatures. On the other hand, increasing carbon content promotes lower twin boundary fractions and larger amounts of low angle boundaries. This effect can be explained by the reduction of grain boundary mobility caused by increasing carbon contents, which in turn reduces the migration rate and consequently the probability of twin boundary generation. Moreover, the increment of low angle boundaries with carbon content accelerates the twin character loss. It was also found that the dynamically recrystallized grain size decreased at increasing carbon content due to a typical drag effect. No important features on textures were found during DDRX

  2. The mechanical properties of austenite stainless steel 304 after structural deformation through cold work

    Energy Technology Data Exchange (ETDEWEB)

    Mubarok, Naila; Manaf, Azwar, E-mail: azwar@ui.ac.id [PPS Materials Science, FMIPA-Universitas Indonesia, Depok 16424 (Indonesia); Notonegoro, Hamdan Akbar [Mechanical Engineering Dept., FT-Universitas Sultan Ageng Tirtayasa,Cilegon 42435 (Indonesia); Thosin, Kemas Ahmad Zaini [Pusat Penelitian Fisika,LIPI, Serpong (Indonesia)

    2016-06-17

    The 304 stainless steel (SS) type is widely used in oil and gas operations due to its excellent corrosion resistance. However, the presence of the fine sand particles and H{sub 2}S gas contained in crude oil could lead the erosion and abrasion in steel. In this study, cold rolled treatments were conducted to the 304 SS in order to increase the wear resistance of the steel. The cold work has resulted in thickness reduction to 20%, 40% and 60% of the original. Various microstructural characterizations were used to analyze the effect of deformation. The hardness characterization showed that the initial hardness value increased from 145 HVC to 395 HVC as the level of deformation increase. Further, the wear resistance increased with the deformation rate from 0% to 40% and subsequently decreased from 40% to 60% deformation rate. Microstructural characterization shows that the boundary change to coincide by 56 µm, 49 µm, 45 µm, and 43 µm width and the grain go to flatten and being folded like needles. The effect of deformation on the grain morphology and structure was also studied by optical metallography and X-Ray Diffraction. It is shown that the deformation by means of a cold rolled process has transformed the austenite structure into martensitic structure.

  3. Effect of prior cold work on creep properties of a titanium modified austenitic stainless steel

    International Nuclear Information System (INIS)

    Vijayanand, V.D.; Parameswaran, P.; Nandagopal, M.; Panneer Selvi, S.; Laha, K.; Mathew, M.D.

    2013-01-01

    Prior cold worked (PCW) titanium-modified 14Cr–15Ni austenitic stainless steel (SS) is used as a core-structural material in fast breeder reactor because of its superior creep strength and resistance to void swelling. In this study, the influence of PCW in the range of 16–24% on creep properties of IFAC-1 SS, a titanium modified 14Cr–15Ni austenitic SS, at 923 K and 973 K has been investigated. It was found that PCW has no appreciable effect on the creep deformation rate of the steel at both the test temperatures; creep rupture life increased with PCW at 923 K and remained rather unaffected at 973 K. The dislocation structure along with precipitation in the PCW steel was found to change appreciably depending on creep testing conditions. A well-defined dislocation substructure was observed on creep testing at 923 K; a well-annealed microstructure with evidences of recrystallization was observed on creep testing at 973 K

  4. SCC crack growth rate of cold worked 316L stainless steel in PWR environment

    Science.gov (United States)

    Du, Donghai; Chen, Kai; Yu, Lun; lu, Hui; Zhang, Lefu; Shi, Xiuqiang; Xu, Xuelian

    2015-01-01

    Many component failures in nuclear power plants were found to be caused by stress corrosion cracking (SCC) of cold worked austenitic steels. Some of the pressure boundary component materials are even cold worked up to 35% plastic deformation, leaving high residual stress and inducing high growth rate of corrosion crack. Controlling water chemistry is one of the best counter measure to mitigate this problem. In this work, the effects of temperature (200 up to 325 °C) and dissolved oxygen (0 up to 2000 μg/L) on SCC crack growth rates of cold worked austenitic stainless steel type 316L have been tested by using direct current potential drop (DCPD) method. The results showed that temperature affected SCC crack growth rates more significantly in oxygenated water than in deaerated water. In argon deaerated water, the crack growth rate exhibited a peak at about 250 °C, which needs further verification. At 325 °C, the SCC crack growth rate increased rapidly with the increase of dissolved oxygen concentration within the range from 0 up to 200 μg/L, while when dissolved oxygen was above 200 μg/L, the crack growth rate followed a shallower dependence on dissolved oxygen concentration.

  5. Estimation of work capacity of welded mounting joints of pipelines of heat resisting steel

    International Nuclear Information System (INIS)

    Gorynin, I.V.; Ignatov, V.A.; Timofeev, B.T.; Blyumin, A.A.

    1982-01-01

    The analysis of a work capacity of circular welds made for the Dsub(y)850 pipeline connection with high pressure vessels of heat resisting steel of the 15Kh1NMFA type has been carried out on the base of test results with small samples and real units. Welds were performed using the manual electric arc welding without the following heat treatment. It has been shown that residual stresses in such welds do not produce an essential effect on the resistance of weld metal and heat affected zone on the formation and developments of cracks

  6. In-reactor creep rupture of 20% cold-worked AISI 316 stainless steel

    International Nuclear Information System (INIS)

    Lovell, A.J.; Chin, B.A.; Gilbert, E.R.

    1981-01-01

    Results of an experiment designed to measure in-reactor stress-to-rupture properties of 20% cold-worked AISI 316 stainless steel are reported. The in-reactor rupture data are compared with postirradiation and unirradiated test results. In-reactor rupture lives were found to exceed rupture predictions of postirradiation tests. This longer in-reactor rupture life is attributed to dynamic point defect generation which is absent during postirradiation testing. The in-reactor stress-to-rupture properties are shown to be equal to or greater than the unirradiated material stress-to-rupture properties for times up to 7000 h. (author)

  7. Fatigue life prediction for a cold worked T316 stainless steel

    International Nuclear Information System (INIS)

    Manjoine, M.J.

    1983-01-01

    Permanent damage curves of initiation-life and propagation-life which predict the fatigue life of specimens of a cold-worked type 316 stainless steel under complex strain-range histories were generated by a limited test program. Analysis of the test data showed that fatigue damage is not linear throughout life and that propagation life is longer than initiation-life at high strain ranges but is shorter at low strain ranges. If permanent damage has been initiated by prior history and/or fabrication, propagation to a given life can occur at a lower strain range than that estimated from the fatigue curves for constant CSR. (author) [pt

  8. Effect of cold work on low-temperature sensitization behaviour of austenitic stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Kain, V. E-mail: vivkain@apsara.barc.ernet.in; Chandra, K.; Adhe, K.N.; De, P.K

    2004-09-01

    The effects of cold work and low-temperature sensitization heat treatment of non-sensitized austenitic stainless steels have been investigated and related to the cracking in nuclear power reactors. Types 304, 304L and 304LN developed martensite after 15% cold working. Heat treatment of these cold worked steels at 500 deg. C led to sensitization of grain boundaries and the matrix and a desensitization effect was seen in 11 days due to fast diffusion rate of chromium in martensite. Types 316L and 316LN did not develop martensite upon cold rolling due to its chemical composition suppressing the martensite transformation (due to deformation) temperature, hence these were not sensitized at 500 deg. C. The sensitization of the martensite phase was always accompanied by a hump in the reactivation current peak in the double loop electrochemical potentiokinetic reactivation test, thus providing a test to detect such sensitization. It was shown that bending does not produce martensite and therefore, is a better method to simulate weld heat affected zone. Bending and heating at 500 deg. C for 11 days led to fresh precipitation due to increased retained strain and desensitization of 304LN due to faster diffusion rate of chromium along dislocations. The as received or solution annealed 304 and 304LN with 0.15% nitrogen showed increased sensitization after heat treatment at 500 deg. C, indicating the presence of carbides/nitrides.

  9. The precipitation response of 20%-cold-worked type 316 stainless steel to simulated fusion irradiation

    International Nuclear Information System (INIS)

    Maziasz, P.J.

    1979-01-01

    The precipitation response of 20%-cold-worked type 316 stainless steel has been examined after irradiation in HFIR at 380-600 0 C, after irradiation in EBR-II at 500 0 C, and after thermal aging at 600 to 750 0 C. Eta phase forms during exposure to all environments. It constitutes a major portion of the precipitation response, and is rich in Ni, Si and Mo relative to M 23 C 6 after thermal aging. It is not normally reported in 20%-cold-worked type 316 stainless steel. The eta, M 23 C 6 , Laves, sigma, and chi precipitate phases appear at similar temperatures after HFIR, EBR-II, or thermal exposure. There are, however, some differences in relative amounts, size, and distribution of phases among the various environments. Eta phase is the only carbide-type phase observed after irradiation in HFIR from 380-550 0 C. The large cavities associated with it at 380 0 C contribute significantly to swelling. Re-solution of fine M 23 C 6 , eta, and Laves particles and re-precipitation of massive particles of sigma, M 23 C 6 and chi are observed after recrystallization in HFIR. (orig.)

  10. Recovery in cold-worked alloy under pressure: example of AISI 316 stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Yousuf, M; Sahu, P C; Raghunathan, V S; Govinda Rajan, K

    1986-06-01

    In this paper we report the behaviour of defects under high pressure in severely cold-deformed 316 stainless steel. In situ electrical resistivity measurements indicate a minimum in the reduced resistivity ratio at 2 GPa associated with a characteristic relaxation time of 500 + - 5 sec. Microhardness data on pressure-treated and recovered samples are consistent with the electrical resistivity behaviour. X-ray powder diffraction rings indicate sharpening beyond 2 GPa. The decrease in the full width at half maximum (FWHM) of the strongest ring is about 2% at pressures beyond 2 GPa. Transmission electron microscopy reveals that samples pressure treated beyond 2 GPa have a polygonized dislocation structure. This is in sharp contrast to the tangled dislocation structure observed in the cold-worked samples. The experimental results suggest a recovery stage in cold-worked stainless steel at 2 GPa. We propose that the recovery process is activated through an enhanced vacancy concentration caused by deformation, a pressure-induced vacancy-dislocation interaction and consequently a pressure-assisted dislocation mobility leading to polygonization.

  11. Study of the microstructure evolution of ferritic stainless ODS steels during hot working

    International Nuclear Information System (INIS)

    Karch, Abdellatif

    2014-01-01

    The production of ODS steels involves a powder consolidation step usually using the hot extrusion (HE) process. The anisotropic properties of extruded materials, especially in the ODS ferritic grades (≥wt%12Cr), need a better understanding of the metallurgical phenomena which may occur during HE and lead to the observed microstructure. The hot working behavior of these materials is of particular interest. The methodology of this work includes the microstructure analysis after interrupted hot extrusion, hot torsion and hot compression (1000-1200 C) tests of ferritic steels with 14%Cr and different amounts in Ti and Y 2 O 3 . The microstructure evolution during hot extrusion process is associated with continuous dynamic recrystallization (CDRX). It leads to the creation of new grains by the formation of low angle boundaries, and then the increase of their misorientation under plastic deformation. The investigations highlight also the role of precipitation on the kinetics of this mechanism; it remains incomplete in the presence of fine and dense nano-precipitates. After hot deformation in torsion and compression, it is noticed that both precipitates and temperature deformation have a significant impact on the deformation mechanisms and microstructure evolution. Indeed, the CDRX is dominant when temperature and amount of reinforcement are limited. However, when they are increased, limited microstructure evolution is observed. In this case, the results are interpreted through a mechanism of strain accommodation at grain boundaries, with low dislocation activity in the bulk of the grains. (author) [fr

  12. Optimized chemical composition, working and heat treatment condition for resistance to irradiation assisted stress corrosion cracking of cold worked 316 and high-chromium austenitic stainless steel

    International Nuclear Information System (INIS)

    Yonezawa, Toshio; Iwamura, Toshihiko; Fujimoto, Koji; Ajiki, Kazuhide

    2000-01-01

    The authors have reported that the primary water stress corrosion cracking (PWSCC) in baffle former bolts made of austenitic stainless steels for PWR after long-term operation is caused by irradiation-induced grain boundary segregation. The resistance to PWSCC of simulated austenitic stainless steels whose chemical compositions are simulated to the grain boundary chemical composition of 316 stainless steel after irradiation increased with decrease of the silicon content, increases of the chromium content, and precipitation of M 23 C 6 carbides at the grain boundaries. In order to develop resistance to irradiation assisted stress corrosion cracking in austenitic stainless steels, optimized chemical compositions and heat treatment conditions for 316CW and high-chromium austenitic stainless steels for PWR baffle former bolts were investigated. For 316CW stainless steel, ultra-low-impurities and high-chromium content are beneficial. About 20% cold working before aging and after solution treatment has also been recommended to recover sensitization and make M 23 C 6 carbides coherent with the matrix at the grain boundaries. Heating at 700 to 725degC for 20 to 50 h was selected as a suitable aging procedure. Cold working of 5 to 10% after aging produced the required mechanical properties. The optimized composition of the high-chromium austenitic stainless steel contents 30% chromium, 30% nickel, and ultra-low impurity levels. This composition also reduces the difference between its thermal expansion coefficient and that of 304 stainless steel for baffle plates. Aging at 700 to 725degC for longer than 40 h and cold working of 10 to 15% after aging were selected to meet mechanical property specifications. (author)

  13. The role of cold work and applied stress on surface oxidation of 304 stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Lozano-Perez, Sergio, E-mail: sergio.lozano-perez@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Rd., Oxford OX1 3PH (United Kingdom); Kruska, Karen [Department of Materials, University of Oxford, Parks Rd., Oxford OX1 3PH (United Kingdom); Iyengar, Ilya [Winchester College, College Street, Winchester SO23 9LX (United Kingdom); Terachi, Takumi; Yamada, Takuyo [Institute of Nuclear Safety System (INSS), 64 Sata, Mihama-cho, Mikata-gun, Fukui 919-1205 (Japan)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer FIB 3D sequential sectioning is an ideal technique to characterize surface oxidation. Black-Right-Pointing-Pointer 3D models of the oxide can be produced with nanometre resolution. Black-Right-Pointing-Pointer The effects of stress and cold work in grain boundary oxidation have been analysed. Black-Right-Pointing-Pointer At least three different oxidation modes are observed when stress is applied. - Abstract: FIB 3-dimensional (3D) sequential sectioning has been used to characterize environmental degradation of 304 stainless steels in pressurized water reactor (PWR) simulated primary water. In particular, the effects of cold work and applied stress on oxidation have been studied in detail. It was found that a description of the oxidation behaviour of this alloy is only complete if it is treated statistically, since it can suffer from high variability depending on the feature described.

  14. Effect of cold works on creep-rupture life of type 316LN stainless steel

    International Nuclear Information System (INIS)

    Kim, W. G.; Han, C. H.; Ryu, W. S.

    2003-01-01

    Effect of cold works on creep-rupture life of the cold-worked type 316LN stainless steels, which are fabricated with the various reductions ; 0%(solution annealing), 20%, 30%, 40%, and 50%, was investigated. The creep-rupture time increased gradually up to 30% reduction, but it decreased inversely over 30% reduction. The longest rupture time exhibited at cold-worked reduction of 30%. The reason for this is that fine carbide precipitates are uniformly generated in grain boundary and the dislocations are pinned in the precipitates and the dislocations are sustained for a long time at high temperature. However, it is assumed that the higher cold-work reductions over 30% lead to excessive generation of deformation faults. The SEM fractrographs of the cold-worked specimens showed dense fracture micrographs, and they did not show intergranular structures in creep fracture mode. From this result, it is believed that the cold-worked specimens were superior in creep-rupture time to solution annealed ones

  15. Microstructure and mechanical behavior of pulsed laser surface melted AISI D2 cold work tool steel

    Science.gov (United States)

    Yasavol, N.; Abdollah-zadeh, A.; Ganjali, M.; Alidokht, S. A.

    2013-01-01

    D2 cold work tool steel (CWTS) was subjected to pulse laser surface melting (PLSM) at constant frequency of 20 Hz Nd: YAG laser with different energies, scanning rate and pulse durations radiated to the surface. Characterizing the PLSM, with optical and field emission scanning electron microscopy, electron backscattered diffraction and surface hardness mapping technique was used to evaluate the microhardness and mechanical behavior of different regions of melting pool. Increasing laser energy and reducing the laser scanning rate results in deeper melt pool formation. Moreover, PLSM has led to entirely dissolution of the carbides and re-solidification of cellular/dendritic structure of a fine scale surrounded by a continuous interdendritic network. This caused an increase in surface microhardness, 2-4 times over that of the base metal.

  16. The Effects of The Industrial Cryogenic Process on The Wear Behaviours of AISI D2 Cold Work Tool Steels

    OpenAIRE

    Ersöz, Enes; Ovalı, İsmail

    2018-01-01

    In this study, industrial cryogenic process afterconventional heat treatment process for various holding time was applied toAISI D2 (DIN 1.2379) cold work tool steel. The effects of the industrialcryogenic process on the wear behavior was investigated. In the wear test 5,10and 15 N forces were carried out to all group specimens at a constant shearrate (3,16 m/s) and three different wear distances. Experimental results showthat cryogenic processing of AISI D2 cold work tool steels have a signi...

  17. Stress corrosion cracking behavior of annealed and cold worked 316L stainless steel in supercritical water

    Energy Technology Data Exchange (ETDEWEB)

    Sáez-Maderuelo, A., E-mail: alberto.saez@ciemat.es; Gómez-Briceño, D.

    2016-10-15

    Highlights: • The alloy 316L is susceptible to stress corrosion cracking in supercritical water. • The susceptibility of alloy 316L increases with temperature and plastic deformation. • Dynamic strain ageing processes may be active in the material. - Abstract: The supercritical water reactor (SCWR) is one of the more promising designs considered by the Generation IV International Forum due to its high thermal efficiency and improving security. To build this reactor, standardized structural materials used in light water reactors (LWR), like austenitic stainless steels, have been proposed. These kind of materials have shown an optimum behavior to stress corrosion cracking (SCC) under LWR conditions except when they are cold worked. It is known that physicochemical properties of water change sharply with pressure and temperature inside of the supercritical region. Owing to this situation, there are several doubts about the behavior of candidate materials like austenitic stainless steel 316L to SCC in the SCWR conditions. In this work, alloy 316L was studied in deaerated SCW at two different temperatures (400 °C and 500 °C) and at 25 MPa in order to determine how changes in this variable influence the resistance of this material to SCC. The influence of plastic deformation in the behavior of alloy 316L to SCC in SCW was also studied at both temperatures. Results obtained from these tests have shown that alloy 316L is susceptible to SCC in supercritical water reactor conditions where the susceptibility of this alloy increases with temperature. Moreover, prior plastic deformation of 316L SS increased its susceptibility to environmental cracking in SCW.

  18. Hardness survey of cold-worked and heat-treated JBK-75 stainless steel alloy

    International Nuclear Information System (INIS)

    Jackson, R.J.; Lucas, R.L.

    1977-01-01

    The alloy JBK-75, an age-hardenable austenitic stainless steel, is similar to commercial A-286, but has certain chemistry modifications to improve weldability and hydrogen compatibility. The principal changes are an increase in nickel and a decrease in manganese with lower limits on carbon, phosphorus, sulfur, silicon, and boron. In this study, the effects of solutionizing time and temperature, quench rate, cold working, and the effects of cold working on precipitation kinetics were examined. Findings show that the solutionizing temperature has a moderate effect on the as-quenched hardness, while times greater than that required for solutionizing do not significantly affect hardness. Quench rate was found to have a small effect on as-quenched hardness, however, hardness gradients did not develop in small bars. It was found that JBK-75 can be significantly strengthened by cold working. Cold working alone produced hardness increases from Rockwell-A 49 to R/sub A/ 68. A recovery-related hardness change was noted on heat treating at 300 and 400 0 C for both as-quenched and as-worked JBK-75. Significant age-hardening was observed at temperatures as low as 500 0 C for as-worked metal. Aging at 600 0 C resulted in maximum hardness in the 75 percent worked sample at about 6 hours (R/sub A/ 73.5) while the 50 percent worked sample was near maximum hardness (R/sub A 72.5) after seven days. THE 25 and 0 percent worked samples were considerably underaged after seven days. Similar type kinetic data were obtained for worked and nonworked metal at 650, 700, 800, 850, 900, 1000, and 1100 0 C for times from 10 minutes to 10,000 minutes (6.7 days). The overall purpose of the hardness survey was to better define the effects of cold work on the stress-relieving range, coherent precipitation range, incoherent precipitation range, recrystallization range, solutionizing range, and grain-growth range

  19. Steel making

    CERN Document Server

    Chakrabarti, A K

    2014-01-01

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

  20. Effect of cold work on decarburization of 2.25Cr-1Mo steel in high temperature sodium

    International Nuclear Information System (INIS)

    Aoki, Norichika; Yoshida, Eiichi; Wada, Yusaku.

    1994-01-01

    It is known that the mechanical properties of a 2.25Cr-1Mo steel deteriorated due to the decarburization during immersion in the melt sodium at high temperatures. In low-alloy steel as well as a 2.25Cr-1Mo steel, precipitation reactions of carbides are known to be accelerated by cold working and aging. Thus, it may be expected that cold working and aging effectively suppress the decarburization of the mechanical properties of a 2.25Cr-1Mo steel because the decarburization will be restrained owing to fixation of carbon as precipitates of the carbides. In the present article, effects of cold-working and heat treatments on the kinetics of the decarburization of a 2.25Cr-1Mo steel has been studied experimentally. The annealed, cold-rolled, and normalized and tempered specimens were immersed in the melt of sodium at 500, 600 and 700degC for 425, 437 and 432h, respectively. On the basis of the observations obtained from these specimens, the experiment was also carried out at 450, 500 and 550degC for 2270 and 5465h. The microstructures before and after the immersion were observed with optical and scanning electron microscopes. An average concentration of carbon in each specimen was analyzed by an inert gas fusion method. The carbides extracted from the specimens were identified by X-ray diffraction. At immersion temperatures of 450 and 500degC, a 10% reduction of the decarburization in thickness by cold-working is sufficiently effective for retardation of the decarburization at both 2270 and 5465h. Whereas, at 550degC, more than 30% reduction in thickness by cold-working is needed for it at 2270h but even 80% reduction in thickness by cold-working causes merely slight retardation of the decarburization at 5465h. (author)

  1. Non-Metallic Inclusions and Hot-Working Behaviour of Advanced High-Strength Medium-Mn Steels

    Directory of Open Access Journals (Sweden)

    Grajcar A.

    2016-06-01

    Full Text Available The work addresses the production of medium-Mn steels with an increased Al content. The special attention is focused on the identification of non-metallic inclusions and their modification using rare earth elements. The conditions of the thermomechanical treatment using the metallurgical Gleeble simulator and the semi-industrial hot rolling line were designed for steels containing 3 and 5% Mn. Hot-working conditions and controlled cooling strategies with the isothermal holding of steel at 400°C were selected. The effect of Mn content on the hot-working behaviour and microstructure of steel was addressed. The force-energetic parameters of hot rolling were determined. The identification of structural constituents was performed using light microscopy and scanning electron microscopy methods. The addition of rare earth elements led to the total modification of non-metallic inclusions, i.e., they replaced Mn and Al forming complex oxysulphides. The Mn content in a range between 3 and 5% does not affect the inclusion type and the hot-working behaviour. In contrast, it was found that Mn has a significant effect on a microstructure.

  2. Starting of H9ANFNb(P91) steel tubing production for energetics in domestic steel-works; Uruchomienie w krajowych hutach produkcji rur ze stali H9AMFNb(P91) przeznaczonych dla energetyki

    Energy Technology Data Exchange (ETDEWEB)

    Wiedermann, J. [Instytut Metalurgii Zelaza, Gliwice (Poland); Bieniek, K. [Huta Jednosc, Siemianowice Slaskie (Poland); Pogoda, K. [Huta Batory, Chorzow (Poland)

    1996-12-31

    The results of primary investigations and attempt of ferritic steel H9AMFNb production in domestic steel-works have been reported. The prototype series of tubes for energetic boilers have been tested and their mechanical properties determined. It has been found the applicability of the material for use in energetics. 9 refs, 4 figs, 3 tabs.

  3. Study of 16KhSN high strength steel in different structural states and under working conditions

    International Nuclear Information System (INIS)

    Skudnov, V.A.; Vorob'ev, I.A.; Kutyajkin, V.G.; Bugrov, Yu.V.

    1985-01-01

    A study was made on the effect of deformation degree (up to 60%) during reducing, drawing and heat treatment (annealing at 750 deg C), quenching from 930 deg C and tempering at 350 deg C) on strength, plasticity, hardening degree, notch sensitivity, density and elasticity characteristics of the steel. The effect of test temperature (from-196 up to 1000 deg C) on tensile strength and plasticity was studied as well. It was established that drawing and reducing of 16KhSN steel in annealed state with strain degrees of up to 60% results to increase of strength characteristics 1.7...2.3 times and decrease of plasticity characteristics by 15...23%, strain hardening coefficient - 2.2 times and the maximum strain energy - by 80 MJ/m 3 . Hardening heat treatment (quenching from 930 deg C+temperating at 350 deg C) affects on mechanical properties of 16KhSN steel in much the same way as cold working, but strength characteristics of heat-treated steel increase 2.6...3.6 times and the maximum strain energy grows by 640 MJ/m 3 . Systematic data on the effect of temperature (-196...1000 deg C) and tensile rate (4 mm/min...5m/s) on strength and plasticity of 16KhSN steel in annealed state were obtained

  4. Integrated modeling of second phase precipitation in cold-worked 316 stainless steels under irradiation

    International Nuclear Information System (INIS)

    Mamivand, Mahmood; Yang, Ying; Busby, Jeremy T.; Morgan, Dane

    2017-01-01

    The current work combines the Cluster Dynamics (CD) technique and CALPHAD-based precipitation modeling to address the second phase precipitation in cold-worked (CW) 316 stainless steels (SS) under irradiation at 300–400 °C. CD provides the radiation enhanced diffusion and dislocation evolution as inputs for the precipitation model. The CALPHAD-based precipitation model treats the nucleation, growth and coarsening of precipitation processes based on classical nucleation theory and evolution equations, and simulates the composition, size and size distribution of precipitate phases. We benchmark the model against available experimental data at fast reactor conditions (9.4 × 10"–"7 dpa/s and 390 °C) and then use the model to predict the phase instability of CW 316 SS under light water reactor (LWR) extended life conditions (7 × 10"–"8 dpa/s and 275 °C). The model accurately predicts the γ' (Ni_3Si) precipitation evolution under fast reactor conditions and that the formation of this phase is dominated by radiation enhanced segregation. The model also predicts a carbide volume fraction that agrees well with available experimental data from a PWR reactor but is much higher than the volume fraction observed in fast reactors. We propose that radiation enhanced dissolution and/or carbon depletion at sinks that occurs at high flux could be the main sources of this inconsistency. The integrated model predicts ~1.2% volume fraction for carbide and ~3.0% volume fraction for γ' for typical CW 316 SS (with 0.054 wt% carbon) under LWR extended life conditions. Finally, this work provides valuable insights into the magnitudes and mechanisms of precipitation in irradiated CW 316 SS for nuclear applications.

  5. Precipitation Behavior of Carbides in H13 Hot Work Die Steel and Its Strengthening during Tempering

    Directory of Open Access Journals (Sweden)

    Angang Ning

    2017-02-01

    Full Text Available The properties of carbides, such as morphology, size, and type, in H13 hot work die steel were studied with optical microscopy, transmission electron microscopy, electron diffraction, and energy dispersive X-ray analysis; their size distribution and quantity after tempering, at different positions within the ingot, were analyzed using Image-Pro Plus software. Thermodynamic calculations were also performed for these carbides. The microstructures near the ingot surface were homogeneous and had slender martensite laths. Two kinds of carbide precipitates have been detected in H13: (1 MC and M6C, generally smaller than 200 nm; and (2 M23C6, usually larger than 200 nm. MC and M6C play the key role in precipitation hardening. These are the most frequent carbides precipitating at the halfway point from the center of the ingot, and the least frequent at the surface. From the center of the ingot to its surface, the size and volume fraction of the carbides decrease, and the toughness improves, while the contribution of the carbides to the yield strength increases.

  6. Microstructure and mechanical behavior of pulsed laser surface melted AISI D2 cold work tool steel

    International Nuclear Information System (INIS)

    Yasavol, N.; Abdollah-zadeh, A.; Ganjali, M.; Alidokht, S.A.

    2013-01-01

    Highlights: ► Melted zone contained fine dendrites in the bottom and equiaxed grains on the top. ► Microstructural refinements of PLSM led to microhardness enhancement. ► Higher scanning rate and lower laser energy were more effective to refine the microstructure. - Abstract: D2 cold work tool steel (CWTS) was subjected to pulse laser surface melting (PLSM) at constant frequency of 20 Hz Nd: YAG laser with different energies, scanning rate and pulse durations radiated to the surface. Characterizing the PLSM, with optical and field emission scanning electron microscopy, electron backscattered diffraction and surface hardness mapping technique was used to evaluate the microhardness and mechanical behavior of different regions of melting pool. Increasing laser energy and reducing the laser scanning rate results in deeper melt pool formation. Moreover, PLSM has led to entirely dissolution of the carbides and re-solidification of cellular/dendritic structure of a fine scale surrounded by a continuous interdendritic network. This caused an increase in surface microhardness, 2–4 times over that of the base metal.

  7. Microstructure and mechanical behavior of pulsed laser surface melted AISI D2 cold work tool steel

    Energy Technology Data Exchange (ETDEWEB)

    Yasavol, N. [Department of Materials Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of); Abdollah-zadeh, A., E-mail: zadeh@modares.ac.ir [Department of Materials Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of); Ganjali, M. [Materials and Energy Research Center, P.O. Box 14155-4777, Karaj (Iran, Islamic Republic of); Alidokht, S.A. [Department of Materials Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Melted zone contained fine dendrites in the bottom and equiaxed grains on the top. Black-Right-Pointing-Pointer Microstructural refinements of PLSM led to microhardness enhancement. Black-Right-Pointing-Pointer Higher scanning rate and lower laser energy were more effective to refine the microstructure. - Abstract: D2 cold work tool steel (CWTS) was subjected to pulse laser surface melting (PLSM) at constant frequency of 20 Hz Nd: YAG laser with different energies, scanning rate and pulse durations radiated to the surface. Characterizing the PLSM, with optical and field emission scanning electron microscopy, electron backscattered diffraction and surface hardness mapping technique was used to evaluate the microhardness and mechanical behavior of different regions of melting pool. Increasing laser energy and reducing the laser scanning rate results in deeper melt pool formation. Moreover, PLSM has led to entirely dissolution of the carbides and re-solidification of cellular/dendritic structure of a fine scale surrounded by a continuous interdendritic network. This caused an increase in surface microhardness, 2-4 times over that of the base metal.

  8. Reparatory and Manufacturing Hard-Facing of Working Parts Made of Stainless Steels in Confectionary Industry

    Directory of Open Access Journals (Sweden)

    S. Rakic

    2012-09-01

    Full Text Available In this paper, for the sake of improving the reparatory hard-facing technology is especially analyzed reparatory hard-facing of tools for manufacturing compressed products in confectionary industry. Those products are being made of a mixture consisting of several powdery components, which is compressed under high pressure. In that way the connection between particles is realized, thus achieving certain hardness and strength of the confectionary product. The considered tool is made of high-alloyed stainless steel. The tool contains 30 identical working places. Besides the production process wear, on those tools, from time to time, appear mechanical damage on some of the products' shape punches, as cracks at the edges, where the products' final shapes are formed. Those damages are small, size wise, but they cause strong effect on the products' final shape. The aggravating circumstance is that the shape punch is extremely loaded in pressure, thus after the reparatory hard-facing, the additional heat treatment is necessary. Mechanical properties in the heat affected zone (HAZ are being leveled by annealing and what also partially reduces the residual internal stresses.

  9. CHARACTERIZATION AND PERFORMANCE OF DUPLEX-COATINGS ON Cr-V COLD WORK TOOL STEEL

    Directory of Open Access Journals (Sweden)

    Peter Jurči

    2015-09-01

    Full Text Available Specimens made of Vanadis 6 steel were heat treated, plasma nitrided and coated with Cr2N. The microstructure, phase constitution and mechanical properties of plasma nitrided areas and duplex-coatings have been investigated using the light microscopy, scanning electron microscopy, X-ray diffraction and microhardness measurements. The adhesion of the coatings and the wear performance were studied using the scratch test and ring-on-plate tribological testing. Worn surfaces were examined by scanning electron microscopy. Nitrided areas formed at lower temperature were free of compound “white” layer while hose developed at higher temperatures contained as the white layer so the nitrided network. Significant increase in substrate hardness was detected due to the nitriding. Beneficial effect of the nitriding on the adhesion of Cr2N coatings was clearly determined whereas the extent in improvement of the adhesion depends on the presence/no presence of “white” layer on the surface. The extent of beneficial effect of plasma nitriding on the wear performance follows the impact of the constitution of nitrided areas on the adhesion. The amelioration of wear performance of Cr2N coatings can be attributed to the supporting effect of hard nitrided intermediate region, which provides excellent resistance of the substrate against plastic deformation, under heavy loading in particular. Practical testing demonstrated many times prolonged service-time of duplex-treated tools for sheet metal working.

  10. Tensile flow and work-hardening behavior of a Ti-modified austenitic stainless steel

    International Nuclear Information System (INIS)

    Sivaprasad, P.V.; Venugopal, S.; Venkadesan, S.

    1997-01-01

    The flow-stress data of a 15Cr-15Ni-2.2Mo-Ti modified austenitic stainless steel in the temperature range 300 to 1,023 K was analyzed in terms of Ludwigson and Voce equations. The parameters of these equations were critically examined with respect to the effect of Ti/C ratio and test temperature. It was found that the Ludwigson equation described the flow behavior adequately up to the test temperature of 923 K, whereas the Voce equation could be employed in the full temperature range. The peaks/plateaus observed in the variation of these parameters as a function of temperature in the intermediate temperature range have been identified as one of the manifestations of dynamic strain aging (DSA). Also, the variation of these parameters with temperature clearly could bring out the different domains of DSA observed in this alloy. The work-hardening analysis of the flow-stress data revealed that in the DSA regime, the onset of stage III hardening is athermal

  11. Analysis of creep data from MOTA irradiation of 20% cold worked 316 stainless steel

    International Nuclear Information System (INIS)

    Garner, F.A.; Toloczko, M.B.; Puigh, R.J.

    1992-01-01

    The objective of this study is to provide insight into the relationship between void swelling, irradiation creep and applied stress. This insight will be used to develop irradiation creep correlations for fusion applications. Analysis of creep data for 20% cold worked 316 stainless steel irradiated in FFTF/MOTA demonstrates that creep-swelling coupling coefficient is not a strong function of temperature and can be assumed to be -0.6 x 10 -2 MPa -1 in the range 400-600 C. It appears, however, that the creep compliance B o is a moderately strong function of temperature and alloy composition. The latter dependency arises primarily because derived values of B o unavoidably incorporate precipitation-related strains that cannot be easily separated from contributions arising from true creep. It has also been found that at ∼550-600 C there is an upper limit on the total diametral strain rate at 0.33%/dpa. In contrast to the conclusion of an earlier experiment, this limitation does not arise initially from the total disappearance of creep, however. The creep rate first increases with the onset of swelling and then diminishes as the swelling rate increases, disappearing only when the swelling rate reaches its steady state value

  12. Swelling in cold-worked 316 stainless steels irradiated in a PWR

    Energy Technology Data Exchange (ETDEWEB)

    Fukuya, Koji; Fujii, Katsuhiko [Institute of Nuclear Safety System Inc., Mihama, Fukui (Japan)

    2001-09-01

    Swelling behavior in a cold-worked 316 stainless steel irradiated up to 53 dpa in a PWR at 290-320degC was examined using high resolution transmission electron microscopy. Small cavities with the average diameter of 1 nm were observed in the samples irradiated to doses above 3 dpa. The average diameter did not increase with increasing in dose. The maximum swelling was as low as 0.042%. The measured helium content and the cavity morphology led to the conclusion that the cavities were helium bubbles. A comparison of the observed cavity microstructure with data from FBR, HFIR and ATR irradiation showed that the cavity structure in PWR at 320degC or less was similar to those in HFIR and ATR irradiation but quite different from those in FBR condition. From a calculation based on the cavity data and kinetic models the incubation dose of swelling was estimated to be higher than 80dpa in the present irradiation condition. (author)

  13. Characterization of the work hardening structure of austenitic steels by X-ray diffraction. Application to the determination of work hardening gradients and the study of recovery

    International Nuclear Information System (INIS)

    Cadalbert, Robert; Baron, J.L.

    1977-01-01

    A method has been developed to determine quantitatively the work hardening of austenitic steels by measurement of the broadening of X-ray diffraction lines. This simple, rapid, accurate and sensible method enables to determine work hardening variations in the thickness of a material. The complete automation of the measurement cycle using a small computer enables to carry out numerous determinations and to process data with accuracy. The unit developed is well adapted to the testing of metallic materials. It is also possible with this method to study the evolution of work hardening in a metal as a function of heat treatments. For instance, the determination of the recovery curves of the crystal lattice in austenitic steels allows to investigate the influence of additions (Mo, Ti) on the recovery kinetics [fr

  14. Deformation path effects on the internal stress development in cold worked austenitic steel deformed in tension

    International Nuclear Information System (INIS)

    Ahmed, I.I.; Grant, B.; Sherry, A.H.; Quinta da Fonseca, J.

    2014-01-01

    The effects of cold work level and strain paths on the flow stress of austenitic stainless steels, including Bauschinger effect and associated internal stresses were investigated with both mechanical testing and neutron diffraction techniques. The main objective was to assess the effects of cold rolling: to 5%, 10%, 20% and 40% reduction and uniaxial straining on the evolution of the internal strains during the re-straining to 5% tensile strain in-situ, which is relevant for stress corrosion cracking (SCC) studies. The results of mechanical testing showed that the yield strength of material increased when it was reloaded in the forward direction and decreased well below the flow stress when the loading direction was reversed, showing a strong Bauschinger effect. The magnitude of Bauschinger effect is independent on whether tensile or compressive prestraining comes first but rather on the amount of prestrain. The assessment of the effect of prestraining methods showed that the magnitude of yield asymmetry was higher in the material prestrained by uniaxial deformation than those prestrained by cold rolling. Neutron diffraction test results showed that the elastic lattice strain difference between the maximum and minimum strain values increased consistently with the applied stress during the re-straining to 5% tensile strain in-situ along the 3 orthogonal directions of the rolled plate. It also emerged that, following the in-situ loading of cold rolled materials to 5% tensile strain, the largest strain difference occurred in the material prestrained to 20% reduction. In cold rolled samples, the peak width increased with cold work levels and during re-straining to 5% along rolling, transverse to rolling and normal directions which simulated reversed condition. In contrast to the cold rolled samples, there was neither increase nor decrease in the peak width of samples prestrained by uniaxial deformation on re-straining in reverse direction. This was rationalised in

  15. The Effect of Hot Working on Structure and Strength of a Precipitation Strengthened Austenitic Stainless Steel

    Science.gov (United States)

    Mataya, M. C.; Carr, M. J.; Krauss, G.

    1984-02-01

    The development of microstructure and strength during forging in a γ' strengthened austenitic stainless steel, JBK-75, was investigated by means of forward extrusion of cylindrical specimens. The specimens were deformed in a strain range of 0.16 to 1.0, from 800°C to 1080°C, and at approximate strain rates of 2 (press forging) and 2 × 103 s-1 (high energy rate forging), and structures examined by light and transmission microscopy. Mechanical properties were determined by tensile testing as-forged and forged and aged specimens. The alloy exhibited an extremely wide variety of structures and properties within the range of forging pzrameters studied. Deformation at the higher strain rate via high energy rate forging resulted in unrecovered substructures and high strengths at low forging temperatures, and static recrystallization and low strengths at high temperatures. In contrast, however, deformation at the lower strain rate via press forging resulted in retention of the well developed subgrain structure and associated high strength produced at high forging temperatures and strains. At lower temperatures and strains during press forging a subgrain structure formed preferentially at high angle grain boundaries, apparently by a creep-type deformation mechanism. Dynamic recrystallization was not an important restoration mechanism for any of the forging conditions. The results are interpreted on the basis of stacking fault energy and the accumulation of strain energy during hot working. The significance of observed microstructural differences for equivalent deformation conditions (iso-Z, where Z is the Zener-Holloman parameter) is discussed in relation to the utilization of Z for predicting hot work structures and strengths. Aging showed that the γ' precipitation process is not affected by substructure and that the strengthening contributions, from substructure and precipitation, were independent and additive. Applications for these findings are discussed in terms

  16. The effect of hot working on structure and strength of a precipitation strengthened austenitic stainless steel

    International Nuclear Information System (INIS)

    Mataya, M.C.; Carr, M.J.; Krauss, G.

    1984-01-01

    The development of microstructure and strength during forging a γ' strengthened austenitic stainless steel, JBK-75, was investigated. The specimens were deformed in a strain range of 0.16 to 1.0, from 800 0 C to 1080 0 C at approximate strain rates of 2 (press forging) and 2 X 10 3 S -1 (high energy rate forging). Mechanical properties were determined by tensile testing as-forged and forged and aged specimens. The alloy exhibited a wide variety of structures and properties within the range of forging parameters studied. Deformation at the higher strain rate via high energy rate forging resulted in unrecovered substructures and high strengths at low forging temperatures, and static recrystallization and low strengths at high temperatures. In contrast, however, deformation at the lower strain rate via press forging resulted in retention of the well developed subgrain structure and associated high strength produced at high forging temperatures and strains. At lower temperatures and strains during press forging a subgrain structure formed preferentially at high angle grain boundaries, apparently by a creep-type deformation mechanism. Dynamic recrystallization was not an important restoration mechanism for any of the forging conditions. The results are interpreted on the basis of stacking fault energy and the accumulation of strain energy during hot working. The significance of microstructural differences for equivalent deformation conditions (iso-Z, where Z is the Zener-Holloman parameter) is discussed in relation to the utilization of Z for predicting hot work structures and strengths. Aging showed that γ' precipitation is not affected by substructure and that the strengthening contributions were independent and additive. Applications for these findings are discussed in terms of process design criteria

  17. Hot deformation and processing maps of K310 cold work tool steel

    International Nuclear Information System (INIS)

    Ezatpour, H.R.; Sajjadi, S.A.; Haddad-Sabzevar, M.; Ebrahimi, G.R.

    2012-01-01

    Highlights: ► The steady state stresses are related to strain rate and temperature. ► The study led to n DRX = 3.95 and Q DRX = 219.65 kJ/(mol K) and α = 1.2 × 10 −2 MPa −1 . ► The safe domain occurs in the region of 1000–1100 °C for a strain rate of 0.1 s −1 . - Abstract: Hot working response of cold work tool steel K310 was investigated by means of compression test at temperature range of 900–1100 °C. The equivalent strain rates used in these tests were 0.01, 0.1 and 1 s −1 , respectively in order to obtain the processing and stability maps of the studied material following the Dynamic Material Model. All the zones of flow instability were studied through scanning electron microscopy (SEM). The microstructure of the samples after deformation was then analyzed by light microscopy and the differences were compared together. The steady state stress obtained from the flow curves was related to strain rate (ε . ) and temperature (T) by means of the well known Zener–Holloman equation. A least square analysis of the data led to n = 3.95 and Q DRX = 219.65 kJ/mol and α = 1.2 × 10 −2 MPa −1 . Also, hardness results showed that by increasing strain from peak to steady state strain, hardness was decreased.

  18. Effect of cold working and aging on high temperature deformation of high Mn stainless steel

    International Nuclear Information System (INIS)

    Yoshikawa, M.; Habara, Y.; Matsuki, R.; Aoyama, H.

    1999-01-01

    By the addition of N, the strength of high Mn stainless steel can be increased. Cold rolling and aging are effective to increase its strength further, and with those treatments this grade is often used for high temperature applications. In this study, creep deformation behavior and high temperature strength of the high Mn stainless steel in cold rolled and aged conditions are discussed as compared to Type 304 stainless steel. It has been revealed that as-rolled specimens show instant elongation at the beginning of creep tests and its amount is larger in the high Mn grade than in Type 304. Also, the creep rate of the high Mn stainless steel is smaller than that of Type 304. These facts may be related to the change in microstructure. (orig.)

  19. Investigations of Surface Topography of Hot Working Tool Steel Manufactured with the Use of 3D Print

    Directory of Open Access Journals (Sweden)

    Grobelny Pawel

    2017-01-01

    Full Text Available The paper presents the possibilities of 3D printing of chosen hot working tool steel for manufacturing ready made parts. Results of examination of the surface topography of material manufactured by the technology Laser CUSING®B (Laser melting with metals on the machine, Concept Laser M1 3D printing of metal parts has the potential to revolutionize the market of manufacturing and supplying parts. It makes it possible to dissipate manufacturing and to produce parts on request at lower cost and less energy consumption. The parameters of the surface topography of the hot working tool steel directly after printing can differ depending on the distance from the base plate. The differences of surface roughness values can amount from 32% to 85% for Ra and from 59% to 85% for Rz in comparison of the sample bottom to its top.

  20. Effect of biomimetic non-smooth unit morphology on thermal fatigue behavior of H13 hot-work tool steel

    Science.gov (United States)

    Meng, Chao; Zhou, Hong; Cong, Dalong; Wang, Chuanwei; Zhang, Peng; Zhang, Zhihui; Ren, Luquan

    2012-06-01

    The thermal fatigue behavior of hot-work tool steel processed by a biomimetic coupled laser remelting process gets a remarkable improvement compared to untreated sample. The 'dowel pin effect', the 'dam effect' and the 'fence effect' of non-smooth units are the main reason of the conspicuous improvement of the thermal fatigue behavior. In order to get a further enhancement of the 'dowel pin effect', the 'dam effect' and the 'fence effect', this study investigated the effect of different unit morphologies (including 'prolate', 'U' and 'V' morphology) and the same unit morphology in different sizes on the thermal fatigue behavior of H13 hot-work tool steel. The results showed that the 'U' morphology unit had the optimum thermal fatigue behavior, then the 'V' morphology which was better than the 'prolate' morphology unit; when the unit morphology was identical, the thermal fatigue behavior of the sample with large unit sizes was better than that of the small sizes.

  1. WORK RELATED MUSCULOSKELETAL DISORDERS OF THE UPPER LIMBS AMONG STEEL INDUSTRY POPULATIONS

    Directory of Open Access Journals (Sweden)

    S. A. Moussavi-Najarkola A. Khavanin

    2007-08-01

    Full Text Available For high occurrences of upper extremity disorders in working populations and in order to compare the occurrence of musculoskeletal alterations due to ergonomic risk factors such as highly force exertion, repetition, awkward posture between exposed and non-exposed groups, the research was carried out in Tabarestan steel industry. All 526 male workers (316 as exposed group : 132 aged 20-35 years, 184 aged >35 years; 210 as Non-exposed group: 89 aged 20-35 years, 121 aged > 35 years performing tasks exposed / not exposed to risk factors for WMSDS of the upper limbs underwent a clinical examinations as well as completing standardized Nordic Musculoskeletal Questionnaires. The anamnestic cases were defined on the basis of pain, paraesthesia, hyposthenia, and vegetative disorders during previous months. Mean age of exposed and non- exposed groups were obtained 36.3 years (SD= 5.9 and 37.9 years (SD = 7.3 respectively. There were distinguished differences in occurrences of WMSDS of upper limbs between two mentioned groups. The major occurrence was found for the right and left hands. Nocturnal and diurnal paraesthesia obtained an occurrence of about 54% and 53% respectively. Data bears witness to the greater occurrence of affected individuals in exposed group, with a non- exposed / exposed ratio of 1:7.2. The greater occurrences of affected individuals in exposed group (P = 0.006 and in subjects>35 years (P = 0.002 were significant. Structural, organizational and educational measures can be applied to prevent WMSDS or diminish the relative effects to acceptable limit.

  2. Dependence of irradiation creep on temperature and atom displacements in 20% cold worked type 316 stainless steel

    International Nuclear Information System (INIS)

    Gilbert, E.R.

    1976-04-01

    Irradiation creep studies with pressurized tubes of 20 percent cold worked Type 316 stainless steel were conducted in EBR-2. Results showed that as atom displacements are extended above 5 dpa and temperatures are increased above 375 0 C, the irradiation induced creep rate increases with both increasing atom displacements and increasing temperature. The stress exponent for irradiation induced creep remained near unity. Irradiation-induced effective creep strains up to 1.8 percent were observed without specimen failure. 13 figures

  3. Influence of cold work on the diffusion of ion-implanted nitrogen in D9 steel using nuclear reaction analysis

    International Nuclear Information System (INIS)

    Arunkumar, J.; David, C.; Panigrahi, B.K.; Nair, K.G.M.

    2014-01-01

    D9 steels and their modified versions are envisaged for use as fuel cladding and wrapper materials in the Indian fast breeder reactor (FBR) programme. The role played by interstitially dissolved nitrogen in steel matrices for the stabilization of austenitic phase, increase of strength and corrosion resistance is well known. Various factors: the role of grain boundaries and the their orientation, stress mediation, grain fragmentation and production of short circuit paths as a result of compressive stress are known to affect the diffusion of nitrogen. Basically, cold working produces plethora of defects throughout the sample as compared to its solution annealed state. Our earlier studies on 1 x10"1"5 and 5x10"1"5 N"1"5 implanted Solution Annealed D9 (SAD9) showed significant vacancy-nitrogen complexes for higher fluence. Hence, thermal diffusion behaviour of nitrogen was studied in 5 x10"1"5 -N"1"5 implanted samples in solution annealed state. In the present study, to understand the influence of cold work, similar thermal diffusion behaviour of nitrogen has been studied in Cold Worked D9 steel (CWD9) using nuclear reaction analysis

  4. Strong tough low-carbon bainite structural steels exposed to heat treatment and mechanical working

    International Nuclear Information System (INIS)

    Lauprecht, W.; Imgrund, H.; Coldren, P.

    1975-01-01

    A review of results of studying the mechanical properties and structure of extremely strong construction low-pearlite and pearlite-free steels subjected to thermomechanical processing (TMP) is presented. The development of TMP of low-pearlite and pearlite-free steels has led to creation of steel of the following composition: 0.06% of C; 1.8% of Mn; 0.3% of Mo; 0.05-0.09% of Nb. Depending on the kind of TMP the most important parameters of which are the temperature of the termination of rolling and the total deformation below 900 deg C, transformation in these steels occurs partially or completely in the intermediate domain. The increased density of dislocations of beinite structure affects substantially the increase in the yield limit. High degrees of squeezing at temperatures below 870 deg C promote formation of ferrite nuclei. The laboratory rolling demonstrates that by selecting the conditions of TMP one can control the mechanical properties of a steel. The sheets of 13 mm thick allow to obtain the guaranteed values of the yield limit of 70 kgf/mm 2 the transition temperature T 50 = -25 deg C, whereas after rolling under different conditions the low-temperature limit of cold shortness is - 125 deg C, and the yield limit - 45 kgf/mm 2 . As followed from the estimate of numerous industrial experiments, with sheets 20 mm thick in hot-rolled state one can obtain the yield limit no less than 50 kgf/mm 2 . On rolling mills that make possible to produce large deformation at low temperature these values can be increased. For instance, with sheets 30 mm thick one can obtain the yield limit of 56 kgf/mm 2 and the transition temperature of - 60 deg C. The dependence of the yield limit on the holding time in steel tempering is given. The steel possesses a considerable reserve of the increase of strength due to dispersion hardening, which after tempering at 600-625 deg C constitutes 8-12 kgf/mm 2 . Because of low carbon content, this steel is characterized by good

  5. Influences of silicon on the work hardening behavior and hot deformation behavior of Fe–25 wt%Mn–(Si, Al) TWIP steel

    International Nuclear Information System (INIS)

    Li, Dejun; Feng, Yaorong; Song, Shengyin; Liu, Qiang; Bai, Qiang; Ren, Fengzhang; Shangguan, Fengshou

    2015-01-01

    Highlights: • Influence of Si on work hardening behavior of Fe–25 wt%Mn TWIP steel was investigated. • Influence of Si on hot deformation behavior of Fe–25 wt%Mn TWIP steel was studied. • Si blocks dislocation glide and favors mechanical twinning in Fe–25 wt%Mn TWIP steel. • The addition of Si increases the hot deformation activation energy of Fe–25 wt%Mn TWIP steel. • The addition of Si retards the nucleation and growth of DRX grains of Fe–25 wt%Mn TWIP steel. - Abstract: The influence of silicon on mechanical properties and hot deformation behavior of austenitic Fe–25 wt%Mn TWIP steel was investigated by means of the comparison research between 25Mn3Al and 25Mn3Si3Al steel. The results show that the 25Mn3Si3Al steel has higher yield strength and higher hardness than that of 25Mn3Al steel because of the solution strengthening caused by Si atoms and possesses higher uniform deformation ability and tensile strength than that of 25Mn3Al steel due to the higher work hardening ability of 25Mn3Si3Al steel. 25Mn3Si3Al steel presents a clear four-stage curve of work hardening rate in course of cold compression. Quite the opposite, the 25Mn3Al steel presents a monotonic decline curve of work hardening rate. The difference of the work hardening behavior between 25Mn3Al and 25Mn3Si3Al steel can be attributed to the decline of stacking fault energy (SFE) caused by the addition of 3 wt% Si. The dislocation glide plays an important role in the plastic deformation of 25Mn3Al steel even though the mechanical twinning is still one of the main deformation mechanisms. The 3 wt% Si added into the 25Mn3Al steel blocks the dislocation glide and promotes the mechanical twinning, and then the dislocation glide characteristics cannot be observed in cold deformed microstructure of 25Mn3Si3Al steel. The hot compression tests reveal that the hot deformation resistance of the 25Mn3Si3Al steel is significantly higher than that of the 25Mn3Al steel due to the solid

  6. Effect of cryogenic treatment on microstructure, mechanical and wear behaviors of AISI H13 hot work tool steel

    Science.gov (United States)

    Koneshlou, Mahdi; Meshinchi Asl, Kaveh; Khomamizadeh, Farzad

    2011-01-01

    This paper focuses on the effects of low temperature (subzero) treatments on microstructure and mechanical properties of H13 hot work tool steel. Cryogenic treatment at -72 °C and deep cryogenic treatment at -196 °C were applied and it was found that by applying the subzero treatments, the retained austenite was transformed to martensite. As the temperature was decreased more retained austenite was transformed to martensite and it also led to smaller and more uniform martensite laths distributed in the microstructure. The deep cryogenic treatment also resulted in precipitation of more uniform and very fine carbide particles. The microstructural modification resulted in a significant improvement on the mechanical properties of the H13 tool steel.

  7. Use of niobium to substitute vanadium in the steel for hot work AISI H3

    International Nuclear Information System (INIS)

    Branco, J.R.T.; Jesus, B.G. de

    1984-01-01

    Experimental results on austenitic grain size, quenching hardness and response to tempering measured on a H13 tool steel modified by niobium additions are described. It is shown that the replacement of 25 and 50% percent of the total vanadium by 0,05% of niobium does not change the response to quenching and tempering. (Author) [pt

  8. Void formation in cold-worked type 316 stainless steel irradiated with 1-MeV protons

    International Nuclear Information System (INIS)

    Keefer, D.W.; Pard, A.G.

    1974-01-01

    Cold-worked Type 316 stainless steel was irradiated at 500 and 600 0 C with 1-MeV protons. The dependence of void formation on displacement damage, irradiation temperature, and microstructure was studied by transmission electron microscopy. Cold working delays the onset of swelling and reduces it, via a reduction in void size, at both irradiation temperatures. Inhomogeneity in the cold-worked microstructure leads to inhomogeneity in the disposition of voids. Swelling at 600 is greater than at 500 0 C; the voids are less numerous but larger at the higher temperature. No change in the cold-worked microstructure can be detected by transmission electron microscopy after 500 0 C irradiation to 23 displacements per atom. Irradiation to a comparable damage level at 600 0 C results in almost complete elimination of the cold-worked microstructure. Comparison of the results is made with data from reactor irradiation experiments

  9. Stress corrosion cracking of stainless steel under deaerated high-temperature water. Influence of cold work and processing orientation

    International Nuclear Information System (INIS)

    Terachi, Takumi; Yamada, Takuyo; Chiba, Goro; Arioka, Koji

    2006-01-01

    The influence of cold work and processing orientation on the propagation of stress corrosion cracking (SCC) of stainless steel under hydrogenated high-temperature water was examined. It was shown that (1) the crack growth rates increased with heaviness of cold work, and (2) processing orientation affected crack growth rate with cracking direction. Crack growth rates showed anisotropy of T-L>>T-S>L-S, with T-S and L-S branches representing high shear stress direction. Geometric deformation of crystal grains due to cold work caused the anisotropy and shear stress also assisted the SCC propagation. (3) The step intervals of slip like patterns observed on intergranular facets increased cold work. (4) Nano-indentation hardness of the crack tip together with EBSD measurement indicated that the change of hardness due to crack propagation was less than 5% cold-work, even though the distance from the crack tip was 10μm. (author)

  10. Steel, specially for the fabrication of welded structure working under pressure in nuclear installations

    International Nuclear Information System (INIS)

    Dolbenko, E.T.; Astafiev, A.A.; Kark, G.S.

    1981-01-01

    The present invention is in the field of metallurgy. Steels have found an increasing number of applications in mechanical constructions, and notably in the construction of materials for the production of energy and for the fabrication of welded structures operating under pressure at temperatures as high as 450 0 C. A possible application is the pressurized vessels of nuclear facilities. The steels of interest contain carbon, silicon, manganese, nickel, molybdenum, vanadium, aluminium, nitrogen, phosphorus and iron, but are characterized by the fact that they also contain arsenic, tin and calcium. The sum of the weighted percentages of nickel and manganese and the weighted percentage of phosphorous are related as follows: (Ni + Mn) . P [fr

  11. Irradiation creep and creep rupture of titanium-modified austenitic stainless steels and their dependence on cold work level

    International Nuclear Information System (INIS)

    Garner, F.A.; Hamilton, M.L.; Eiholzer, C.R.; Toloczko, M.B.; Kumar, A.S.

    1991-11-01

    A titanium-modified austenitic type stainless steel was tested at three cold work levels to determine its creep and creep rupture properties under both thermal aging and neutron irradiation conditions. Both the thermal and irradiation creep behavior exhibit a complex non-monotonic relationship with cold work level that reflects the competition between a number of stress-sensitive and temperature-dependent microstructural processes. Increasing the degree of cold work to 30% from the conventional 20% level was detrimental to its performance, especially for applications above 550 degrees c. The 20% cold work level is preferable to the 10% level, in terms of both in-reactor creep rupture response and initial strength

  12. Experimental Work at Harwell on the Injection of Sodium into Liquid Steel

    International Nuclear Information System (INIS)

    Asher, R.C.; Bradshaw, L.; Collett, R.; Davies, D.

    1976-01-01

    The equipment and experimental technique used to inject molten sodium beneath the surface of molten steel (and subsequently molten uranium dioxide) are described. The results of an exploratory experiment, in which 2 g of sodium at 380 deg. C were injected into 54 g of steel at 1530 deg. C, are outlined. A violent reaction occurred, apparently as a result of a vapour explosion, and a number of pulses were recorded by a force transducer. A preliminary examination of the steel debris is reported. In conclusion: The injection of ∼2 g of sodium at ∼380 deg. C beneath the surface of ∼54 g of steel at 1530 deg. C resulted in a vapour explosion. A series of three pulses (perhaps more) at intervals of ∼6 ms were observed; the peak amplitude was at least 600 N (equivalent to a pressure of ∼20 bar on the base of the crucible). The steel was highly dispersed giving material of predominant particle size ∼500 μ and calculated surface area ∼13.5 cm 2 g -1 ; the particles were almost spherical but some had a small indentation on their surface. The apparatus operated very well, especially considering its rudimentary nature and the speed with which it was assembled. Nevertheless experience of the first experiment showed that many improvements are desirable. (a) Interpretation of the pulses recorded by the force transducer was difficult and would be facilitated by the use of a strong crucible and by a redesigned pillar. (b) Instrumentation on the injector would enable t M and t I to be determined and would permit the injection timing to be related to the pulse record, thus giving a measure of the dwell time. (c) The closed circuit television needs to be linked to a video tape recorder. (d) The recording instrumentation should have a better resolution so that short pulses are not lost or inaccurately recorded; a multichannel tape recorder may be desirable. (e) Direct measurement of the surface area of the debris should be carried out using an existing technique (BET low

  13. Logistics simulation of in-bound raw materials to steel works for 2.4 mt expansion

    Energy Technology Data Exchange (ETDEWEB)

    Baijal, A.D.; Misbhra, O.P.; Das, S.; Banerjee, R.S.; Dash, S. [Tata Iron and Steel Company Ltd. (India)

    2005-07-01

    A logistics simulation was carried out to capture the possible scenarios of in-bound raw material traffic in light of Tata's Steel works 2.4 Mt expansion plan. Results from the simulation show that the number of tracks, track hoppers/tipplers and stockyard capacities are sufficient to handle the increased volumes of in-coming rakes. It also suggests that the number of locos can be rationalised without any adverse affect on the rake circuit times. 7 figs., 4 tabs.

  14. Effect of unit size on thermal fatigue behavior of hot work steel repaired by a biomimetic laser remelting process

    Science.gov (United States)

    Cong, Dalong; Li, Zhongsheng; He, Qingbing; Chen, Dajun; Chen, Hanbin; Yang, Jiuzhou; Zhang, Peng; Zhou, Hong

    2018-01-01

    AISI H13 hot work steel with fatigue cracks was repaired by a biomimetic laser remelting (BLR) process in the form of lattice units with different sizes. Detailed microstructural studies and microhardness tests were carried out on the units. Studies revealed a mixed microstructure containing martensite, retained austenite and carbide particles with ultrafine grain size in units. BLR samples with defect-free units exhibited superior thermal fatigue resistance due to microstructure strengthening, and mechanisms of crack tip blunting and blocking. In addition, effects of unit size on thermal fatigue resistance of BLR samples were discussed.

  15. Influence of pre-heating on the surface modification of powder-metallurgy processed cold-work tool steel during laser surface melting

    Energy Technology Data Exchange (ETDEWEB)

    Šturm, Roman, E-mail: roman.sturm@fs.uni-lj.si [University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana (Slovenia); Štefanikova, Maria [University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana (Slovenia); Steiner Petrovič, Darja [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia)

    2015-01-15

    Graphical abstract: - Highlights: • Heat-treatment protocol for laser surface melting of cold-work tool steel is proposed. • The laser melted steel surface is hardened, and morphologically modified. • The pre-heating of substrate creates a crack-and pore-free steel surface. • The optimum pre-heating temperature is determined to be 350 °C. • Using pre-heating the quantity of retained austenite is reduced. - Abstract: In this study we determine the optimal parameters for surface modification using the laser surface melting of powder-metallurgy processed, vanadium-rich, cold-work tool steel. A combination of steel pre-heating, laser surface melting and a subsequent heat treatment creates a hardened and morphologically modified surface of the selected high-alloy tool steel. The pre-heating of the steel prior to the laser surface melting ensures a crack- and pore-free modified surface. Using a pre-heating temperature of 350 °C, the extremely fine microstructure, which typically evolves during the laser-melting, became slightly coarser and the volume fraction of retained austenite was reduced. In the laser-melted layer the highest values of microhardness were achieved in the specimens where a subsequent heat treatment at 550 °C was applied. The performed thermodynamic calculations were able to provide a very valuable assessment of the liquidus temperature and, especially, a prediction of the chemical composition as well as the precipitation and dissolution sequence for the carbides.

  16. Mathematical Modelling of Carbonitride Precipitation during Hot Working in Nb Microalloyed Steels

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Based on thermodynamics and kinetics, precipitation behavior of microalloyed steels was analyzed. Deformation greatly promotes isothermal carbonitride precipitation and makes C-curve shift leftwards. The position and shape of C-curve also depend on the content of Nb and N. C-curve shifts leftwards a little when N content increases and the nose temperature is raised with increasing Nb content. Deformation shortened precipitation start time during continuous cooling, raised precipitation start temperature, accelerated precipitation kinetics of carbonitrides. With decreasing the finishing temperature and coiling temperature, the precipitates volume fraction increases and strength increment is raised during hot rolling. The simulated results are in agreementwith experiment results.

  17. Characterization of an AISI H-13 steel for work in hot

    International Nuclear Information System (INIS)

    Godinez, J.; Robles, E.

    1998-01-01

    Two materials were acquired which elaborated through secondary refining processes known as electroslag refusing (ESR) and electric arc in vacuum refusing (VAR) were acquired. These materials were thermically treated, for subsequently to determine their mechanical properties in longitudinal and transversal directions with respect to rolling direction, moreover they were characterized through scanning electron microscopy and X-ray diffraction determining microstructure, carbides and non-metallic inclusions. The results of the mechanical essays allowed to evaluate the fracture toughness to this steel by the Barsom and Rolfe method. (Author)

  18. SCC of cold-worked austenitic stainless steels exposed to PWR primary water conditions: susceptibility to initiation

    International Nuclear Information System (INIS)

    Herms, E.; Raquet, O.; Sejourne, L.; Vaillant, F.

    2009-01-01

    Heavily cold-worked austenitic stainless steels (AISI 304L and 316L types) could be significantly susceptible to Stress Corrosion Cracking (SCC) when exposed to PWR nominal primary water conditions even in absence of any pollutants. Susceptibility to SCC was shown to be related with some conditions such as initial hardness, procedure of cold-work or dynamic straining. A dedicated program devoted to better understand the initiation stage on CW austenitic stainless steels in PWR water is presented. Initiation is studied thanks to SCC test conditions leading to an intergranular cracking propagation mode on a CW austenitic stainless steel which is the mode generally reported after field experience. SCC tests are carried out in typical primary water conditions (composition 1000 ppm B and 2 ppm Li) and for temperature in the range 290 - 340 C. Material selected is 316L cold-worked essentially by rolling (reduction in thickness of 40%). Initiation tests are carried out under various stress levels with the aim to investigate the evolution of the initiation period versus the value of applied stress. SCC tests are performed on cylindrical notched specimens in order to increase the applied stress and allow accelerated testing without modify the exposure conditions to strictly nominal hydrogenated PWR water. Respective influences of cyclic/dynamic conditions on SCC initiation are presented and discussed. Dedicated interrupted tests help to investigate the behaviour of the crack initiation process. These SCC tests have shown that crack initiation could be obtained after a very short time under dynamic loading conditions on heavily pre-strained austenitic stainless steels. Actual results show that the most limiting stage of the cracking process on CW 316L seems to be the transition from slow transgranular propagation of surface initiated cracks to intergranular fast propagation through the thickness of the sample. The duration of this stage during crack initiation tests is

  19. Effect of heat treatment, with and without mechanical work, on the tensile and creep behaviour at 6000C of austenitic stainless steel stabilised with titanium

    International Nuclear Information System (INIS)

    Padilha, A.F.

    1983-01-01

    The effect of various heat treatments, with and without mechanical work, on the microstructure and the tensile and creep behaviour at 600 0 C of the titanium stabilised austenitic stainless steel DIN 1.4970, as well as the effects of aging temperature, pre-strain and small boron additions on the creep behaviour of these steels are discussed. The most probable mechanism is suggested. (Author) [pt

  20. Neutron irradiation effects in reactor pressure vessel steels and weldments. Working document

    International Nuclear Information System (INIS)

    1998-10-01

    As a result of the popularity of the Agencies report 'Neutron Irradiation Embrittlement of Reactor Pressure Vessel Steels' of 1975, it was decided that another report on this broad subject would be of use. In this report, background and contemporary views on specially identified areas of the subject are considered as self-contained chapters, written by experts. A separate abstract was prepared for the introduction and for each of the eleven chapters, which are: 1. Reactor Pressure Vessel Design, 2. Reactor Pressure Materials, 3. WWER Pressure Vessels, 4. Determination of Mechanical Properties, 5. Neutron Exposure, 6. Methodology of Irradiation Experiments, 7. Effect of Irradiation on Mechanical Properties, 8. Mechanisms of Irradiation Embrittlement, 9. Modelling of Irradiation Damage, 10. Annealing of Irradiation Damage, 11. Safety Assessment using Surveillance Programmes and Data Bases

  1. Processing parameters for the mechanical working of 9 Cr-1 Mo steel: processing maps approach

    Energy Technology Data Exchange (ETDEWEB)

    Sivaprasad, P.V.; Mannan, S.L.; Prasad, Y.V.R.K. [Indira Ghandi Centre for Atomic Research, Tamilnadu (India)

    2004-12-15

    Processing and instability maps using a dynamic materials model have been developed for 9Cr-1Mo steel in the temperature range 850 to 1200{sup o}C and strain rate range 0.001-100 s{sup -1} with a view to optimising its hot workability. The efficiency of power dissipation increased with increase in temperature and decrease in strain rate. The 9Cr-1Mo material exhibited two dynamic recrystallisation domains, one with a peak efficiency of 37% occurring at 950{sup o}C and 0.001 s{sup -1} and the other with a peak efficiency of 35% occurring at 1200{sup o}C and 0.1 s{sup -1}. These results are in good agreement with those found in industry. (author)

  2. The toughness of cold worked 316 stainless steel at 20 degrees C

    Energy Technology Data Exchange (ETDEWEB)

    Chipperfield, C G [UKAEA, RNPDL, Risley (United Kingdom)

    1977-07-01

    General Yielding Fracture Mechanics Concepts have been used to evaluate and compare thickness effects, J-integral estimation procedures and methods of crack detection in three point bend test pieces of prestrained 316 stainless steel. The results suggest that no thickness effects will exist in irradiated test pieces so long as the failure mode is one of ductile fracture. The choice of toughness parameter, whether fracture initiation be characterised in terms of the contour integral J or Crack Opening Displacement, appears to be relatively unimportant since both criteria appear to predict critical defect sizes of similar magnitude. Suitable crack monitoring procedures have been evaluated for subsequent irradiated tests, and it would appear that a direct current potential drop technique is the most sensitive for a given specimen geometry and toughness level. (author)

  3. Study of the performances of nano-case treatment cutting tools on carbon steel work material during turning operation

    Science.gov (United States)

    Afolalu, S. A.; Okokpujie, I. P.; Salawu, E. Y.; Abioye, A. A.; Abioye, O. P.; Ikumapayi, O. M.

    2018-04-01

    The degree of holding temperature and time play a major role in nano-case treatment of cutting tools which immensely contributed to its performance during machining operation. The objective of this research work is to carryout comparative study of performance of nano-case treatment tools developed using low and medium carbon steel as work piece. Turning operation was carried out under two different categories with specific work piece on universal lathe machine using HSS cutting tools 100 mm × 12mm × 12mm that has been nano-case treated under varying conditions of temperatures and timeof 800,850, 900, 950°C and 60, 90, 120 mins respectively. The turning parameters used in evaluating this experiment were cutting speed of 270, 380 and 560mm/min, feed rate of 0.15, 0.20 and 0.25 mm/min, depth of cut of 2mm, work piece diameter of 25mm and rake angle of 7° each at three levels. The results of comparative study of their performances revealed that the timespent in the machining of low carbon steel material at a minimum temperature and time of 800°C, 60 mins were1.50, 2.17 mins while at maximum temperature and time of 950°C, 120 mins were 1.19, 2.02 mins. It was also observed that at a corresponding constant speed of 270,380 and 560mm/min at higher temperature and time, a relative increased in the length of cut were observed. Critical observation of the result showed that at higher case hardening temperature and time (950°C/120mins), the HSS cutting tool gave a better performance as lesser time was consumed during the turning operation.

  4. An investigation into the effects of conventional heat treatments on mechanical characteristics of new hot working tool steel

    Science.gov (United States)

    Fares, M. L.; Athmani, M.; Khelfaoui, Y.; Khettache, A.

    2012-02-01

    The effects of conventional heat treatments, i.e. quenching and tempering, on the mechanical characteristics of non standard hot work tool steel, close to either AISI-H11/H13 are investigated. The major elemental composition differences are in carbon, silicon and vanadium. The objective of the carried heat treatments is to obtain an efficient tool performance in terms of hardness, wear resistance and mechanical strength. Experimental results allow an explanation of the surface properties depending mainly on both chemical composition and optimised preheating parameters. After austenitizing at 1050 °C for 15 min, the as-quenched steel in oil bath exhibited the fully martensitic structure (without bainite) connected to a small fraction of retained austenite and complex carbides mainly of M23C6 type. Twice tempering at 500 °C and 600 °C resulted in initiating the precipitation processes and the secondary hardness effect. As a result, carbide content amounted to 3% while the retained austenite content decreased to 0%. Accordingly, the required mechanical properties in terms of hardness and wear are fulfilled and are adequately favourable in handling both shocks and pressures for the expected tool life. Induced microstructures are revealed using optical and scanning electron microscopes. Phase compositions are assessed by means of X-ray diffraction technique while mechanical characteristics are investigated based on hardness and abrasive wear standard tests.

  5. Relationship between 0.2% proof stress and Vickers hardness of work-hardened low carbon austenitic stainless steel, 316SS

    International Nuclear Information System (INIS)

    Matsuoka, Saburo

    2004-01-01

    Stress corrosion cracking (SCC) occurs in shrouds and piping made of low carbon austenitic stainless steels at nuclear power plants. A work-hardened layer is considered to be one of the probable causes for this occurrence. The maximum Vickers hardness measured at the work-hardened layer is 400 HV. It is important to determine the yield strength and tensile strength of the work-hardened layer in the investigation on the causes of SCC. However, the tensile specimen cannot be obtained since the thickness of the work-hardened layer is as mall as several hundred μm, therefore, it is useful if we can estimate these strengths from its Vickers hardness. Consequently, we investigated the relationships between Vickers hardness versus yield strength and tensile strength using the results obtained on various steels in a series of Fatigue Data Sheets published by the National Institute for Materials Science and results newly obtained on a parent material and rolled materials (reduction of area: 10 - 50%, maximum hardness: 350 HV) for a low carbon stainless steel. The results showed that (1) the relationship between the 0.2% proof stress and the Vickers hardness can be described by a single straight line regardless of strength, structure, and rolling ratio, however, (2) the tensile strength is not correlated with the Vickers hardness, and the austenitic stainless steel in particular shows characteristics different from those of other steels. (author)

  6. Improvement of strength and toughness of SKD11 type cold work tool steel; SKD 11 gata reikan koguko no kyojinsei no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Fukaura, K.; Sunada, H.; Yokoyama, Y. [Himeji Inst. of Technology, Hyogo (Japan); Teramoto, K. [Himeji Inst. of Technology, Hyogo (Japan). Graduate School| Sanyo Special Steel Co. Ltd., Hyogo (Japan)

    1998-03-01

    Toughness and wear resistance are the factors which affect on the lifetime of cold work tool steels importantly. Generally, both properties show the contrary characteristics. The evaluation of tool steel materials has been carried out focusing on the strength and wear resistance mainly. However, owing to the rapid progress of recent plastic working techniques, usage environments are under the severe conditions more and more. Therefore, it is expected to develop the high reliable cold work tool steels which balanced with toughness including wear resistance. In this study, the strength and toughness of a newly developed 0.8C-8Cr cold work tool steel whose composition was controlled to suppress the precipitation of massive eutectic M7C3 carbides were investigated with reference to microstructure and were compared with conventional SKD11. The toughness was evaluated by the area under the stress-strain curve. As a result, it was clarified that the tensile strength of the newly developed steel designated as Mod. SKD 11 was about 400 MPa higher and the toughness was 1.8 times larger than that of SKD 11 throughout a wide range of tempering temperatures and so forth. 17 refs., 13 figs., 1 tab.

  7. Effect of cold working on biocompatibility of Ni-free high nitrogen austenitic stainless steels using Dalton's Lymphoma cell line

    International Nuclear Information System (INIS)

    Talha, Mohd; Kumar, Sanjay; Behera, C.K.; Sinha, O.P.

    2014-01-01

    The aims of the present work are to explore the effect of cold working on in-vitro biocompatibility of indigenized low cost Ni-free nitrogen containing austenitic stainless steels (HNSs) and to compare it with conventionally used biomedical grade, i.e. AISI 316L and 316LVM, using Dalton's Lymphoma (DL) cell line. The MTT assay [3-(4,5-dimethythiazol 2-yl)-2,5-diphenyltetrazolium bromide] was performed on DL cell line for cytotoxicity evaluation and cell adhesion test. As a result, it was observed that the HNS had higher cell proliferation and cell growth and it increases by increasing nitrogen content and degree of cold working. The surface wettability of the alloys was also investigated by water contact angle measurements. The value of contact angles was found to decrease with increase in nitrogen content and degree of cold working. This indicates that the hydrophilic character increases with increasing nitrogen content and degree of cold working which further attributed to enhance the surface free energy (SFE) which would be conducive to cell adhesion which in turn increases the cell proliferation. - Graphical abstract: Effect of cold working on in-vitro biocompatibility of indigenized Ni-free nitrogen bearing austenitic stainless steels was explored using Dalton's Lymphoma cell line. Cell proliferation and cell adhesion increase by increasing the degree of cold working and nitrogen content in steel indicating that indigenized material is more biocompatible and no negative effect of cold working on these steels. - Highlights: • Effect of cold working on biocompatibility of Ni-free austenitic stainless steels • Cell proliferation and adhesion increase with nitrogen and degree of cold working. • Contact angle values decrease with nitrogen and degree of cold working

  8. Effect of temperature on the mechanical characteristics of cold-worked steel OKh16N15M3B with active tension and creep

    International Nuclear Information System (INIS)

    Erasov, V.S.; Konoplenko, V.P.; Pirogov, E.N.

    1986-01-01

    Steel OKh16N15M3B is used extensively for the manufacture of atomic reactor fuel-element shells. The aim of this work is a study of the mechanical characteristics of this steel cold-worked by 20% with active tension and creep in the temperature range 973-1323 0 K, which is necessary for predicting the behavior of fuel-element shells in critical situations. It is found that above 973 0 K there is active loss of strength for cold-worked steel OKh16N15M3B. Strength characteristics in the region 973-1323 0 K decrease by more than a factor of six. Thermal activation analysis of the plastic deformation process, showing a sharp increase in activation energy above 1073 0 K, suggests a change in the mechanisms of plastic deformation taking place. For active tension and creep the same temperature range is obtained for a marked change in activation energy

  9. Residual stress measurement in worked and heat treated steel by X-ray diffractometry

    International Nuclear Information System (INIS)

    Sinha, V.K.; Godaba, V.S.

    2008-01-01

    Investigations were made for residual stress measurement by X-ray diffractometry in the 1.14% C, 0.46% Mn, 0.16% Si, 0.11% S and 0.04% P steel samples subjected to inhomogeneous plastic deformation (cold upsetting in the range 7.7-21%), thermal gradient (quenching from 630 deg. C) and phase transformation (quenching from 850 deg. C), respectively. The results indicated that compressive residual stress at the surface increased in the samples with increasing deformation acquiring values in the range, -269.5 MPa to -374.7 MPa. In the samples quenched from 630 deg. C, the thermal stresses acquired increasing values in the range -83.9 MPa (compressive) to -188.1 MPa (compressive) with increased cooling rate. In the samples quenched from 850 deg. C, volume increase on account of austenite to martensite phase transformation ultimately dominated the thermal contraction resulting in residual stress at the surface from -329.3 MPa (compressive) to +61.7 MPa (tensile)

  10. Effect of cold working on the aging and corrosion behavior of Fe-Mn-Al stainless steel

    International Nuclear Information System (INIS)

    Ghayad, I.M.; Girgis, N.N.; Ghanem, W.; Hamada, A.S.

    2004-01-01

    The cold working; aging process; and corrosion behavior of the Fe-Mn-Al stainless steel having a composition of Fe-29wt%Mn-3.5wt%Al-0.5wt%C were investigated. Three different groups of specimens of the alloy were subjected to different procedures of cold working and aging. The first group were cold worked then solution treated at 1100 deg. C for 24 hr, coded as CW+ST. The second group were cold worked, solution treated at 1100 deg. C for 24 hr then cold worked again, coded as CW+ST+CW. The third group were solution treated at 1100 deg. C for 24 hr then cold worked, coded as ST+CW. Subsequent aging treatments of the controlled-worked alloy showed age hardening similar to that reported for the solution-treated alloys. The strengthening of the experimental alloy due to the controlled-working and aging is discussed on the basis of microstructural observations and X-ray diffraction analysis. The corrosion behavior of the different groups of the alloy, CW+ST; CW+ST+CW; ST+CW, with their peak aged and over aged conditions has been examined in 3.5% NaCl solution. The electrochemical techniques, potentiodynamic polarization and Tafel plots were employed. All the alloy groups did not passivate in 3.5% NaCl solution and the major corrosion type observed was general corrosion. The peak aged and over aged of the CW+ST+CW exhibited higher corrosion rates due to the formation of ferrite phase that formed a galvanic couple with the austenitic matrix. (authors)

  11. A constitutive model accounting for strain ageing effects on work-hardening. Application to a C-Mn steel

    Science.gov (United States)

    Ren, Sicong; Mazière, Matthieu; Forest, Samuel; Morgeneyer, Thilo F.; Rousselier, Gilles

    2017-12-01

    One of the most successful models for describing the Portevin-Le Chatelier effect in engineering applications is the Kubin-Estrin-McCormick model (KEMC). In the present work, the influence of dynamic strain ageing on dynamic recovery due to dislocation annihilation is introduced in order to improve the KEMC model. This modification accounts for additional strain hardening rate due to limited dislocation annihilation by the diffusion of solute atoms and dislocation pinning at low strain rate and/or high temperature. The parameters associated with this novel formulation are identified based on tensile tests for a C-Mn steel at seven temperatures ranging from 20 °C to 350 °C. The validity of the model and the improvement compared to existing models are tested using 2D and 3D finite element simulations of the Portevin-Le Chatelier effect in tension.

  12. Specifics of formation the portfolio of orders on the basis of break even analysis for Iron and Steel Works

    Directory of Open Access Journals (Sweden)

    Zambrzhitskaia Evgenia

    2017-01-01

    Full Text Available The issue of orders portfolio formation becomes more and more actual in terms of evolving economy crisis, consequences of which turned into the growing competition both in domestic and foreign markets. Goals of research – formalization of order portfolio formation procedure. The purpose of our academic research – to develop the algorithm for order portfolio formation suitable for iron and steel works. The article suggests the possibility of using break-even analysis indices, in particular, the research introduces a «break-even point» concept in terms of efficient order portfolio. Usage of break-even point indices is more preferable to others (marginal revenue, cost-effectiveness and etc. the main advantages of the suggested analysis are: 1 great information capacity from the point of management decision making; 2 the suggested analysis is less governed by price factor than marginal revenue.

  13. The effect of cold work on grain boundary precipitation and sensitization in nitrogen added type 316L stainless steels

    International Nuclear Information System (INIS)

    Seo, Moo Hong; Chun, Byong Sun; Oh, Yong Jun; Ryu, Woo Seog; Hong, Jun Hwa

    1998-01-01

    The precipitation and sensitization behavior of nitrogen added type 316L Stainless Steels (SS) were investigated by using specimens cold worked for 0∼40%. The alloys had a variation in nitrogen content from 0.04 to 0.15%. To quantify the degree of sensitization, Double-Loop Electrochemical Potentiokinetic Reactivation (DL-EPR) test was performed in a 0.1M H 2 SO 4 + 0.01M KSCN solution at 30 .deg. C. The addition of nitrogen increased sensitization resistance by retarding the onset of M 23 C 6 precipitation and shifted Time-Temperature-Sensitization(TTS) curve to higher temperature and longer time range. Cold work accelerated the M 23 C 6 precipitation and sensitization kinetic due to the increase in dislocation density. However, the acceleration of sensitization was found to depend on the added nitrogen content in the alloys. The alloys with high nitrogen(>0.1%N) content exhibited higher acceleration of the sensitization as a function of the cold work than that with low nitrogen content. From the microstructural analysis, this was found to be attributed to the development of intensive slip bands during cold work and retardation of dislocation annihilation during subsequent aging in the alloys with high nitrogen content

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

    CERN Document Server

    John Minehara, Eisuke

    2004-01-01

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

  15. Characterizing of steel used in the construction of civil works in Almeria; Caracterizacion mecanica de aceros empleados en el sector de la construccion de Almeria

    Energy Technology Data Exchange (ETDEWEB)

    Senobua, A. J.; Garzon, E.; Ayuso, J.; Perez, F.; Caballero, A.

    2003-07-01

    Various tests have been conducted on the steel bars used in the construction of civil works in Almeria (Spain) during the period 18 January 2000-7May 2001, with the aim of mechanically characterizing the different types of steel (weldable; B400S, B500S and ductile weldable: B400SD) to determine whether there is a technical reason for the increase in the use of ductile weldable steel. For this, we have used a hydraulic machine to break by traction all the test samples that arrived to the laboratory, following the specifications of the UNE 7474-1:1992 and the UNE 7474-2:1992. The results indicate that only in 86% of the cases does the steel B400SD satisfy the limits specified by the UNE 36065:1999-EX, as opposed to 95 and 94% of the B400S and B500S steels. In addition the ductile weldable steel registered mean values lower than those of B400S. This findings disagrees with expectations set by the specifications. (Author) 6 refs.

  16. USE OF HIGH SPEED STEEL WORK ROLLS (HSS ON APERAM STECKEL MILL

    Directory of Open Access Journals (Sweden)

    Arísio de Abreu Barbosa

    2013-12-01

    Full Text Available This paper outlines the main actions taken to reinforce the decision to use HSS work rolls on the Aperam Steckel Mill. These are: work roll cooling improvements, systematically analyzing Eddy Current and Ultrasonic non destructive tests, mechanical adjustment of work roll crown and critically examining the rolling process. These actions applied together have contributed to the success of HSS rolls state of the art application, and provide the Steckel Mill with a much improved performance. Significant results have been achieved, such as: increasing of work roll change intervals, increasing of the available production time, a yield gain, a product quality improvement, less working hours needed for the roll grinding operation, etc

  17. Study on the blasting demolition of steel construction. Part 2. Demolition work of steel tower; Tekkotsu kozobutsu no bakuha kaitai ni kansuru kenkyu. 2. Koro yagura happa kaitai koji

    Energy Technology Data Exchange (ETDEWEB)

    Ogata, Y.; Wada, Y.; Katsuyama, K. [National Institute for Resources and Environment, Tsukuba (Japan); Nishida, T.; Hoshino, M.; Nagano, M. [Kacoh Co. Ltd., Tokyo (Japan)

    1997-06-30

    This paper describes the blasting demolition of steel tower of iron works. The steel tower had four columns, and its dimension was 17 mtimes17 m in cross section and 77.6 m height. The total weight was about 1,724 t. The 18.4 kg V-type linear shaped charge was fixed around columns with box weld structures, and initiated using 16 seismograph electric detonators. Vibration and noise were measured during blasting and collapse of the tower. In the both case, the vibration levels were between 67 and 71 dB, which were low and under 75 dB, the standard level during specific construction works of the regulation act of vibration. The noise level was 120 dB(A) at the point 200 m away from the blasting source, which was over 85 dB(A), the standard level. The collapse process of steel tower was simulated using discontinuous deformation analysis. The results agreed well with those from the actual collapse. The steel tower landed about 6 seconds after the initiation, and it took about 15 seconds to complete the collapse. Before the demolition, the 6 t parts of forefeet of two columns in the collapse direction were cut and removed by blasting. Thus, the collapse was controlled in the given direction. 5 refs., 13 figs., 2 tabs.

  18. Role of cavity formation in SCC of cold worked carbon steel in high-temperature water. Part 2. Study of crack initiation behavior

    International Nuclear Information System (INIS)

    Yamada, Takuyo; Aoki, Masanori; Miyamoto, Tomoki; Arioka, Koji

    2013-01-01

    To consider the role of cavity formation in stress corrosion cracking (SCC) of cold worked (CW) carbon steel in high-temperature water, SCC and creep growth (part 1) and initiation (part 2) tests were performed. The part 2 crack initiation tests used blunt notched compact tension (CT) type specimens of CW carbon steel exposed under the static load condition in hydrogenated pure water and in air in the range of temperatures between 360 and 450°C. Inter-granular (IG) crack initiation was observed both in water and in air even in static load condition when steel specimens had been cold worked. 1/T type temperature dependencies of initiation times were observed for CW carbon steel, and the crack initiation times in an operating pressurized heavy water reactor, PHWR (Pt Lepreau) seemed to lie on the extrapolated line of the experimental results. Cavities were identified at the grain boundaries near the bottom of a notch (highly stressed location) before cracks initiated both in water and air. The cavities were probably formed by the condensation of vacancies and they affected the bond strength of the grain boundaries. To assess the mechanism of IGSCC initiation in high temperature water, the diffusion of vacancies driven by stress gradients was studied using a specially designed CT specimen. As a model for IGSCC in CW carbon steel in high temperature water, it was concluded that the formation of cavities from the collapse of vacancies offers the best interpretation of the present data. (author)

  19. The effects of annealing temperature and cooling rate on carbide precipitation behavior in H13 hot-work tool steel

    International Nuclear Information System (INIS)

    Kang, Minwoo; Park, Gyujin; Jung, Jae-Gil; Kim, Byung-Hoon; Lee, Young-Kook

    2015-01-01

    Highlights: • Unexpected Mo carbides formed during slow cooling from low annealing temperatures. • Mo carbides formed during the migration of Mo for a transition of Cr-rich carbide. • Mo carbides were precipitated at the boundaries of M 7 C 3 carbides and ferrite grains. • Annealing conditions for the precipitation of Mo carbides were discussed. - Abstract: The precipitation behavior of H13 hot-work tool steel was investigated as a function of both annealing temperature and cooling rate through thermodynamic calculations and microstructural analyses using transmission and scanning electron microscope and a dilatometer. The V-rich MC carbide and Cr-rich M 7 C 3 and M 23 C 6 carbides were observed in all annealed specimens regardless of annealing and cooling conditions, as expected from an equilibrium phase diagram of the steel used. However, Mo-rich M 2 C and M 6 C carbides were unexpectedly precipitated at a temperature between 675 °C and 700 °C during slow cooling at a rate of below 0.01 °C/s from the annealing temperatures of 830 °C and below. The solubility of Mo in both M 7 C 3 and ferrite reduces with decreasing temperature during cooling. Mo atoms diffuse out of both M 7 C 3 and ferrite, and accumulate locally at the interface between M 7 C 3 and ferrite. Mo carbides were form at the interface of M 7 C 3 carbides during the transition of Cr-rich M 7 C 3 to stable M 23 C 6

  20. SCC growth behavior of stainless steel weld metals in high-temperature water. Influence of corrosion potential, weld type, thermal aging, cold-work and temperature

    International Nuclear Information System (INIS)

    Yamada, Takuyo; Terachi, Takumi; Miyamoto, Tomoki; Arioka, Koji

    2009-01-01

    Recent studies on crack growth rate measurement in oxygenated high-temperature pure water conditions, such as normal water chemistry in boiling water reactors, using compact tension type specimens have shown that weld stainless steels are susceptible to stress corrosion cracking. However, to our knowledge, there is no crack growth data of weld stainless steels in pressurized water reactor primary water. The principal purpose of this study was to examine the SCC growth behavior of stainless steel weld metals in simulated PWR primary water. A second objective was to examine the effect of (1) corrosion potential, (2) thermal-aging, (3) Mo in alloy and (4) cold-working on SCC growth in hydrogenated and oxygenated water environments at 320degC. In addition, the temperature dependence of SCC growth in simulated PWR primary water was also studied. The results were as follows: (1) No significant SCC growth was observed on all types of stainless steel weld metals: as-welded, aged (400degC x 10 kh) 308L and 316L, in 2.7 ppm-hydrogenated (low-potential) water at 320degC. (2) 20% cold-working markedly accelerated the SCC growth of weld metals in high-potential water at 320degC, but no significant SCC growth was observed in the hydrogenated water, even after 20% cold-working. (3) No significant SCC growth was observed on stainless steel weld metals in low-potential water at 250degC and 340degC. Thus, stainless steel weld metals have excellent SCC resistance in PWR primary water. On the other hand, (4) significant SCC growth was observed on all types of stainless steel weld metals: as-weld, aged (400degC x 10 kh) and 20% cold-worked 308L and 316L, in 8 ppm-oxygenated (high-potential) water at 320degC. (5) No large difference in SCC growth was observed between 316L (Mo) and 308L. (6) No large effect on SCC growth was observed between before and after aging up to 400degC for 10 kh. (7) 20% cold-working markedly accelerated the SCC growth of stainless steel weld metals. (author)

  1. The effect of hot deformation on the bainite transformation of a working tool steel; Efeito da deformacao a quente sobre a transformacao bainitica de um aco ferramenta

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca Lima, Ricardo F. de; Carvalho, Miguel A.; Nogueira, Marcos A.S. [Acos Villares SA, Rio de Janeiro, RJ (Brazil)

    1989-12-31

    The effect of hot deformation of austenite on its isothermal transformation at 400 degrees Celsius for a hot working steel has been investigated. The degrees of transformation was varied and the results were analysed by optical metallography. Increasing the deformation, the bainite nucleation occurs in twins and grain boundaries, and also inside the austenitic grains. (author). 10 refs., 8 figs.

  2. Optimization of Ferritic Steel Porous Supports for Protonic Fuel Cells Working at 600°C

    DEFF Research Database (Denmark)

    Molin, Sebastian; Chen, Ming; Bonanos, Nikolaos

    2014-01-01

    oxide fuel cell. In this work corrosion properties of a Fe22Cr0.4Mn alloy in porous form are evaluated in humidified hydrogen at 600°C and a method to improve its corrosion resistance is reported. Supports in the not modified state corrode rapidly by formation of dual phase oxides whereas after...

  3. Greening Steel Work: Varieties of Capitalism and the "Greening" of Skills

    Science.gov (United States)

    Evans, Claire; Stroud, Dean

    2016-01-01

    An important driver of change in work, employment and skills is European Union policy aims of sustainable economic growth and the cultivation of a green economy. Part of the latter--which is supported by increasing environmental regulation--focuses on the development of a "green skills agenda," which involves the "greening" of…

  4. Tensile stress-strain and work hardening behaviour of P9 steel for wrapper application in sodium cooled fast reactors

    Science.gov (United States)

    Christopher, J.; Choudhary, B. K.; Isaac Samuel, E.; Mathew, M. D.; Jayakumar, T.

    2012-01-01

    Tensile flow behaviour of P9 steel with different silicon content has been examined in the framework of Hollomon, Ludwik, Swift, Ludwigson and Voce relationships for a wide temperature range (300-873 K) at a strain rate of 1.3 × 10 -3 s -1. Ludwigson equation described true stress ( σ)-true plastic strain ( ɛ) data most accurately in the range 300-723 K. At high temperatures (773-873 K), Ludwigson equation reduces to Hollomon equation. The variations of instantaneous work hardening rate ( θ = dσ/ dɛ) and θσ with stress indicated two-stage work hardening behaviour. True stress-true plastic strain, flow parameters, θ vs. σ and θσ vs. σ with respect to temperature exhibited three distinct temperature regimes and displayed anomalous behaviour due to dynamic strain ageing at intermediate temperatures. Rapid decrease in flow stress and flow parameters, and rapid shift in θ- σ and θσ- σ towards lower stresses with increase in temperature indicated dominance of dynamic recovery at high temperatures.

  5. Methods of forging steel

    OpenAIRE

    Pečoler, Primož

    2014-01-01

    The following work presents processes of steel forming, challenges when forging steel, forming machines suitable for forging and which choice of machine is most suitable for forging. We can separate steel forming to free forging and drop forging. Free forging can be divided to hand forging and machine forging. The correct choice of furnaces is also very important. We must reach correct temperature in the furnace for raw steel to melt with less scalings. In diploma I mentioned some machine...

  6. Understanding the Effect of Ni on Mechanical and Wear Properties of Low-Carbon Steel from a View-Point of Electron Work Function

    Science.gov (United States)

    Lu, Hao; Huang, Xiaochen; Hou, Runfang; Li, D. Y.

    2018-04-01

    Electron work function (EWF) is correlated to intrinsic properties of metallic materials and can be an alternative parameter to obtain supplementary clues for guiding material design and modification. A higher EWF corresponds to a more stable electronic state, leading to higher resistance to any attempt to change the material structure and properties. In this study, effects of Ni as a solute with a higher EWF on mechanical, electrochemical, and tribological properties of low-carbon steel were investigated. Added Ni, which has more valence electrons, enhanced the electrons-nuclei interaction in the steel, corresponding to higher EWF. As a result, the Ni-added steel showed increased mechanical strength and corrosion resistance, resulting in higher resistances to wear and corrosive wear. Mechanism for the improvements is elucidated through analyzing EWF-related variations in Young's modulus, hardness, corrosion potential, and tribological behavior.

  7. Crack growth testing of cold worked stainless steel in a simulated PWR primary water environment to assess susceptibility to stress corrosion cracking

    International Nuclear Information System (INIS)

    Tice, D.R.; Stairmand, J.W.; Fairbrother, H.J.; Stock, A.

    2007-01-01

    Although austenitic stainless steels do not show a high degree of susceptibility to stress corrosion cracking (SCC) in PWR primary environments, there is limited evidence from laboratory testing that crack propagation may occur under some conditions for materials in a cold-worked condition. A test program is therefore underway to examine the factors influencing SCC propagation in good quality PWR primary coolant. Type 304 stainless steel was subjected to cold working by either rolling (at ambient or elevated temperature) or fatigue cycling, to produce a range of yield strengths. Compact tension specimens were fabricated from these materials and tested in simulated high temperature (250-300 o C) PWR primary coolant. It was observed that the degree of crack propagation was influenced by the degree of cold work, the crack growth orientation relative to the rolling direction and the method of working. (author)

  8. Stress relaxation in solution-annealed and 20% cold-worked Type 316 stainless steel

    International Nuclear Information System (INIS)

    Thomas, J.F. Jr.; Yaggee, F.L.

    1975-01-01

    Relaxation experiments were conducted at room temperature and various levels of tensile plastic strain. The data for both solution-annealed (SA) and 20 percent cold-worked (CW) material can be presented in terms of a single family of nonintersecting hardness curves. Although the hardness curves for SA can be reduced to a master curve, those for CW fail to fit this master curve at strain rates below 5 x 10 -6 s -1 . The slope of the hardness scaling relation increases with plastic deformation. (DLC)

  9. Correlation of fracture toughness with tensile properties for irradiated 20% cold-worked 316 stainless steel

    International Nuclear Information System (INIS)

    Hamilton, M.L.; Garner, F.A.; Wolfer, W.G.

    1983-08-01

    A correlation has been developed which allows an estimate to be made of the toughness of austenitic alloys using more easily obtained tensile data. Tensile properties measured on 20% cold-worked AISI 316 specimens made from ducts and cladding irradiated in EBR-II were used to predict values for the plane strain fracture toughness according to a model originally developed by Krafft. Some microstructural examination is required to determine a parameter designated as the process zone size. In contrast to the frequently employed Hahn-Rosenfeld model, this model gives results which agree with recent experimental determinations of toughness performed in the transgranular failure regime

  10. Tensile stress–strain and work hardening behaviour of P9 steel for wrapper application in sodium cooled fast reactors

    International Nuclear Information System (INIS)

    Christopher, J.; Choudhary, B.K.; Isaac Samuel, E.; Mathew, M.D.; Jayakumar, T.

    2012-01-01

    Highlights: ► σ–ε behaviour has been adequately described by Ludwigson and Hollomon equations. ► Instantaneous work hardening rate (θ) exhibited two-stage behaviour. ► σ–ε, flow parameters, θ and θσ vs.σ exhibited three distinct temperature regimes. ► Influence of dynamic strain ageing at intermediate temperatures has been identified. ► Dominance of dynamic recovery at high temperatures was demonstrated. - Abstract: Tensile flow behaviour of P9 steel with different silicon content has been examined in the framework of Hollomon, Ludwik, Swift, Ludwigson and Voce relationships for a wide temperature range (300–873 K) at a strain rate of 1.3 × 10 −3 s −1 . Ludwigson equation described true stress (σ)–true plastic strain (ε) data most accurately in the range 300–723 K. At high temperatures (773–873 K), Ludwigson equation reduces to Hollomon equation. The variations of instantaneous work hardening rate (θ = dσ/dε) and θσ with stress indicated two-stage work hardening behaviour. True stress–true plastic strain, flow parameters, θ vs. σ and θσ vs. σ with respect to temperature exhibited three distinct temperature regimes and displayed anomalous behaviour due to dynamic strain ageing at intermediate temperatures. Rapid decrease in flow stress and flow parameters, and rapid shift in θ–σ and θσ–σ towards lower stresses with increase in temperature indicated dominance of dynamic recovery at high temperatures.

  11. SNPDL work in support of collaborative programmes to study fatigue crack propagation in light water reactor pressure vessel steels

    International Nuclear Information System (INIS)

    McMinn, A.

    1981-07-01

    Work performed at Springfields Nuclear Power Development Laboratories (SNL) in support of United Kingdom and international cooperative groups is described. For the UK collaborative group crack growth tests have been performed on A533-B pressure vessel steel in air at 1 Hz, and in a simulated PWR environment at 1 Hz and 0.0167 Hz, all tests being at a stress ratio (R) of 0.7. Tests were performed at SNL at ambient temperature and pressure. The results showed that enhancements in crack growth rates were obtained because of the aqueous environment and the lower cyclic frequency. Good inter-laboratory agreement was obtained for the air test, indicating that there was little variation in the mechanical control between laboratories. There was also good agreement between the results from laboratories where tests were performed under high temperature wet conditions at 1 Hz. SNL room temperature data demonstrated an effect of temperature, as the crack growth rates found were up to a factor of four lower than the high temperature data. Although crack growth could be maintained at 0.0167 Hz and low cyclic stress intensity levels at ambient temperature, this was not found to be possible by the laboratories performing the test at 288 0 C. The first international 'round robin' test at R = 0.2 and 0.0167 Hz (1 cycle/min) in an aqueous environment gave a significant amount of scatter in the results. (author)

  12. Nitrogen effect on precipitation and sensitization in cold-worked Type 316L(N) stainless steels

    International Nuclear Information System (INIS)

    Oh, Yong Jun; Hong, Jun Hwa

    2000-01-01

    The precipitation behavior and sensitization resistance of Type 316L(N) stainless steels containing different concentrations of nitrogen have been investigated at the aging condition of 700 deg. C for cold work (CW) levels ranging from 0% (as solution annealed) to 40% reduction in thickness. The precipitation of M 23 C 6 carbide and intermetallic compounds (χ, Laves and σ phase) was accelerated by increasing the CW level. Nitrogen in the deformed alloys retarded the inter- and intra-granular precipitation of the carbides at low and high CW levels respectively, whereas it increased the relative amount of the χ phase. Quantitative assessment of the degree of sensitization (DOS) using the double loop-electrochemical potentiokinetic reactivation (DL-EPR) tests indicated that CW levels up to 20% enhanced sensitization while 40% CW suppressed sensitization for all aging times. The increase in nitrogen content accelerated the sensitization at CW levels below 20%. This might be associated with the homogeneous distribution of dislocations and the lower tendency toward recrystallization exhibited in the alloys having higher nitrogen content

  13. Effect of axial stress on the transient mechanical response of 20%, cold-worked Type 316 stainless-steel cladding

    International Nuclear Information System (INIS)

    Yamada, H.

    1979-01-01

    To understand the effects of the fuel-cladding mechanical interaction on the failure of 20% cold-worked Type 316 stainless-steel cladding during anticipated nuclear reactor transients, the transient mechanical response of the cladding was investigated using a transient tube burst method at a heating rate of 5.6 0 C/s and axial-to-hoop-stress ratios in the range of 1/2 to 2. The failure temperatures were observed to remain essentially constant for the transient tests at axial-to-hoop-stress ratios between 1/2 and 1, but to decrease with an increase in axial-to-hoop-stress ratios above unity. The uniform diametral strains to failure were observed to decrease monotonically with an increase in axial-to-hoop-stress ratio from 1/2 to 2, and in general, the uniform axial strains to failure were observed to increase with an increase in axial-to-hoop-stress ratio. The fracture of the cladding during thermal transients was found to be strongly affected by the maximum principal stress but not by the effective stress

  14. Effects of picosecond laser repetition rate on ablation of Cr12MoV cold work mold steel

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Baoye; Deng, Leimin; Liu, Peng; Zhang, Fei; Duan, Jun, E-mail: duans@hust.edu.cn; Zeng, Xiaoyan

    2017-07-01

    In this paper, the effects of pulse repetition rate on ablation efficiency and quality of Cr12MoV cold work mold steel have been studied using a picosecond (ps) pulse Nd:YVO{sub 4} laser system at λ= 1064 nm. The experimental results of area ablation on target surface reveal that laser repetition rate plays a significant role in controlling ablation efficiency and quality. Increasing the laser repetition rate, while keeping a constant mean power improves the ablation efficiency and quality. For each laser mean power, there is an optimal repetition rate to achieve a higher laser ablation efficiency with low surface roughness. A high ablation efficiency of 42.29, 44.11 and 47.52 μm{sup 3}/mJ, with surface roughness of 0.476, 0.463 and 0.706 μm could be achieved at laser repetition rate of 10 MHz, for laser mean power of 15, 17 and 19 W, respectively. Scanning electron microcopy images revels that the surface morphology evolves from rough with numerous craters, to flat without pores when we increased the laser repetition rate. The effects of laser repetition rate on the heat accumulation, plasma shield and ablation threshold were analyzed by numerical simulation, spectral analysis and multi-laser shot, respectively. The synergetic effects of laser repetition rate on laser ablation rate and machining quality were analyzed and discussed systemically in this paper.

  15. Study of tensile test behavior of austenitic stainless steel type 347 seamless thin-walled tubes in cold worked condition

    Energy Technology Data Exchange (ETDEWEB)

    Terui, Clarice, E-mail: clarice.terui@marinha.mil.br [Centro Tecnológico da Marinha em São Paulo (CINA/CTMSP), Iperó, SP (Brazil). Centro Industrial Nuclear da Marinha; Lima, Nelson B. de, E-mail: nblima@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNE-SP), Sao Paulo, SP (Brazil)

    2017-07-01

    These austenitic stainless steel type 347 seamless thin-walled tubes are potential candidates to be used in fuel elements of nuclear power plants (as PWR - Pressurized Water Reactor). So, their metallurgical condition and mechanical properties, as the tensile strength and yield strength, normally are very restrict in demanding project and design requirements. Several full size tensile tests at room temperature and high temperature (315 deg C) were performed in these seamless tubes in cold-worked condition. The results of specified tensile and yield strengths were achieved but the elongation of the tube, in the geometry of the component, could not be measured at high temperature due to unconventional mode of rupture (helical mode without separation of parts). The average value of elongation was obtained from stress-strain curves of hot tensile tests and was around 5%. The results obtained in this research show that this behavior of the full size tensile test samples of thin-walled tube (wall thickness less than 0.5 mm) in high temperature (315°C) is due to the combination of the manufacturing process, the material (crystallographic structure and chemical composition) and the final geometry of the component. In other words, the strong crystallographic texture of material induced by tube drawing process in addition with the geometry of the component are responsible for the behavior in hot uniaxial tensile tests. (author)

  16. Effects of cold work, sensitization treatment, and the combination on corrosion behavior of stainless steels in nitric acid

    International Nuclear Information System (INIS)

    Mayuzumi, M.; Ohta, J.; Arai, T.

    1998-01-01

    In a reprocessing process, spent nuclear fuels from light-water reactors are dissolved in nitric acid (HNO 3 ) to separate and recover the fissile materials such as uranium and plutonium from the radioactive fission products. Corrosion behavior of two stainless steels (SS) was investigated in nitric acid (HNO 3 ) for the effect of cold work (CW), sensitization heat treatment (Sens.), and a combination (CW + Sens.). The corrosion rate of the solution-treated type 304 SS (UNS S30400) with extra-low carbon (type 304ELC SS (UNS S30403)) increased with time and reached constant values after 1,000 h of immersion. However, constant corrosion rates were obtained for 25% Cr-20% Ni-Nb (type 310Nb SS [UNS S31040]) from the initial stage of immersion. CW mitigated corrosion of the solution-treated SS. The effect of CW was different on the two types of SS, with the sensitization heat-treated type 304 ELC SS showing higher corrosion rates and type 310Nb SS lower corrosion rates by CW. Corrosion resistance of type 310Nb SS was superior to type 304 ELC SS after all treatments. Chromium concentration of the sensitization-treated type 304 ELC SS was lower in the grain-boundary region than of the solution-treated one, although no chromium carbide precipitation was observed. This may have been the cause of intergranular corrosion enhancement by sensitization treatment

  17. Steel alloys

    International Nuclear Information System (INIS)

    Bloom, E.E.; Stiegler, J.O.; Rowcliffe, A.F.; Leitnaker, J.M.

    1977-01-01

    The invention deals with a fuel element for fast breeder reactors. It consits essentially of a uranium oxide, nitride, or carbide or a mixture of these fuels with a plutonium or thorium oxide, nitride, or carbide. The fuel elements are coated with an austenitic stainless steel alloy. Inside the fuel elements, vacancies or small cavities are produced by neutron effects which causes the steel coating to swell. According to the invention, swelling is prevented by a modification of type 304, 316, 321, or 12 K 72HV commercial steels. They consist mainly of Fe, Cr, and Ni in a ratio determined by a temary diagram. They may also contain 1.8 to 2.3% by weight of Mo and a fraction of Si (0.7 to 2% by weight) and Ti(0.10 to 0.5% by weight) to prevent cavity formation. They are structurally modified by cold working. (IHOE) [de

  18. Structural integrity of stainless steel components exposed to neutron irradiation. Change in failure strength of cracked components due to cold working

    International Nuclear Information System (INIS)

    Kamaya, Masayuki; Hojo, Tomohiro; Mochizuki, Masahito

    2015-01-01

    Load carrying capacity of austenitic stainless steel component is increased due to hardening caused by neutron irradiation if no crack is included in the component. On the other hand, if a crack is initiated in the reactor components, the hardening may decrease the load carrying capacity due to reduction in fracture toughness. In this paper, in order to develop a failure assessment procedure of irradiated cracked components, characteristics of change in failure strength of stainless steels due to cold working were investigated. It was experimentally shown that the proof and tensile strengths were increased by the cold working, whereas the fracture toughness was decreased. The fracture strengths of a cylinder with a circumferential surface crack were analyzed using the obtained material properties. Although the cold working altered the failure mode from plastic collapse to the unsteady ductile crack growth, it did not reduce failure strengths even if 50% cold working was applied. The increase in failure strength was caused not only by increase in flow stress but also by reduction in J-integral value, which was brought by the change in stress-strain curve. It was shown that the failure strength of the hardened stainless steel components could be derived by the two-parameter method, in which the change in material properties could be reasonably considered. (author)

  19. Inelastic properties evolution of alloy steels in martensitic and cold-worked states subjected to heat treatments up to 600/sup 0/C

    Energy Technology Data Exchange (ETDEWEB)

    Isore, A; Miyada, L T

    1975-05-01

    Two internal friction peaks were observed in a ball-bearing steel in the martensitic and cold-worked states, near 220 and 280/sup 0/C for a frequency of about 1,3 Hz. From peaks evolution by annealing up to 600/sup 0/C, it is possible to follow the decomposition stages of martensitic and recrystallization of cold-worked pearlite. Annealed martensite and cold worked pearlite have the same anelastic behaviour. From existing atomistic models, it is possible to interpret these peaks by dislocations-interstitial carbon and dislocations-carbides interactions.

  20. Inelastic properties evolution of alloy steels in martensitic and cold-worked states subjected to heat treatments up to 6000C

    International Nuclear Information System (INIS)

    Isore, A.; Miyada, L.T.

    1975-01-01

    Two internal friction peaks were observed in a ball-bearing steel in the martensitic and cold-worked states, near 220 and 280 0 C for a frequency of about 1,3 Hz. From peaks evolution by annealing up to 600 0 C, it is possible to follow the decomposition stages of martensitic and recrystallization of cold-worked pearlite. Annealed martensite and cold worked pearlite have the same anelastic behaviour. From existing atomistic models, it is possible to interpret these peaks by dislocations-interstitial carbon and dislocations-carbides interactions

  1. 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.

  2. Fatigue damage evolution of cold-worked austenitic nickel-free high-nitrogen steel X13CrMnMoN18-14-3 (1.4452)

    Energy Technology Data Exchange (ETDEWEB)

    Tikhovskiy, I.; Weiss, S.; Fischer, A. [Univ. of Duisburg-Essen, Materials Science and Engineering II, Duisburg (Germany)

    2004-07-01

    Due to the fact that the risk of Ni-allergies becomes more and more important for modern therapies, the necessity of Ni-free implant materials becomes increasingly important. Beside Co- and Ti-base alloys Ni-free high-nitrogen steels may offer an attractive alternative. The present work presents the austenitic high-nitrogen and nickel-free steel X13CrMnMoN18-14-3, (Material No.: 1.4452) after 20% cold-working. In addition this material was deformed under axial cyclic total strain controlled fatigue tests at room temperature. The development of dislocation structure due to different loading amplitudes was compared to none cyclically deformed material. The good mechanical und fatigue properties of these austenitic high-nitrogen steels as well as the better tribological, chemical and biological properties compared to CrNiMo-steels qualify these steels as a promising alternative in medical applications. (orig.)

  3. EAF smelting trials of waste-carbon briquettes at Avesta Works of Outokumpu Stainless AB for recycling oily mill scale sludge from stainless steel production

    Energy Technology Data Exchange (ETDEWEB)

    Yang Qixing; Bjoerkman, Bo [Div. of Process Metallurgy, Lulea Univ. of Tech., Lulea (Sweden); Holmberg, Nils [Raw Materials Handling, Avesta Works, Outokumpu Stainless AB, Avesta (Sweden)

    2009-06-15

    The EAF steel plant of Avesta Works, Outokumpu Stainless AB, has been used to perform smelting reduction trials of briquettes consisting of oily mill scale sludge, carbon and other wastes. A total of 7 briquette smelting trials were performed. The heats were processed smoothly smelting 3 t of briquettes or 3.4 mass-% of metal charges. The quantities of FeSi powder and O{sub 2} gas injected and electric energy supplied were increased to smelt briquettes of 6 t. No impacts were found on the analyses of the crude stainless steel tapped from the EAF during the trials. The results of the briquette smelting have been evaluated by referring to the data from the reference heats and results from earlier laboratory tests. The recovery of Cr, Ni and Fe elements from the briquettes was nearly complete and was found to occur mainly through carbon reduction. The slag masses were not increased in three trials as compared with the reference heats. There were moderate increases in the slag masses in four trial heats. The increases were, nevertheless, lower by 52-69% than the slag masses generated by Si-reduction of the briquette oxides. Afterwards, by referring results from the present trials, waste-carbon briquettes amounting to 1-3 t were smelted very smoothly in many of the EAF heats at Avesta Works to recycle the oily mill scale sludge and other wastes from stainless steel production. (orig.)

  4. An Incremental Physically-Based Model of P91 Steel Flow Behaviour for the Numerical Analysis of Hot-Working Processes

    Directory of Open Access Journals (Sweden)

    Alberto Murillo-Marrodán

    2018-04-01

    Full Text Available This paper is aimed at modelling the flow behaviour of P91 steel at high temperature and a wide range of strain rates for constant and also variable strain-rate deformation conditions, such as those in real hot-working processes. For this purpose, an incremental physically-based model is proposed for the P91 steel flow behavior. This formulation considers the effects of dynamic recovery (DRV and dynamic recrystallization (DRX on the mechanical properties of the material, using only the flow stress, strain rate and temperature as state variables and not the accumulated strain. Therefore, it reproduces accurately the flow stress, work hardening and work softening not only under constant, but also under transient deformation conditions. To accomplish this study, the material is characterised experimentally by means of uniaxial compression tests, conducted at a temperature range of 900–1270 °C and at strain rates in the range of 0.005–10 s−1. Finally, the proposed model is implemented in commercial finite element (FE software to provide evidence of the performance of the proposed formulation. The experimental compression tests are simulated using the novel model and the well-known Hansel–Spittel formulation. In conclusion, the incremental physically-based model shows accurate results when work softening is present, especially under variable strain-rate deformation conditions. Hence, the present formulation is appropriate for the simulation of the hot-working processes typically conducted at industrial scale.

  5. Variations of fracture toughness and stress-strain curve of cold worked stainless steel and their influence on failure strength of cracked pipe

    International Nuclear Information System (INIS)

    Kamaya, Masayuki

    2016-01-01

    In order to assess failure probability of cracked components, it is important to know the variations of the material properties and their influence on the failure load assessment. In this study, variations of the fracture toughness and stress-strain curve were investigated for cold worked stainless steel. The variations of the 0.2% proof and ultimate strengths obtained using 8 specimens of 20% cold worked stainless steel (CW20) were 77 MPa and 81 MPa, respectively. The respective variations were decreased to 13 and 21 MPa for 40% cold worked material (CW40). Namely, the variation in the tensile strength was decreased by hardening. The COVs (coefficients of variation) of fracture toughness were 7.3% and 16.7% for CW20 and CW40, respectively. Namely, the variation in the fracture toughness was increased by hardening. Then, in order to investigate the influence of the variations in the material properties on failure load of a cracked pipe, flaw assessments were performed for a cracked pipe subjected to a global bending load. Using the obtained material properties led to variation in the failure load. The variation in the failure load of the cracked pipe caused by the variation in the stress-strain curve was less than 1.5% for the COV. The variation in the failure load caused by fracture toughness variation was relatively large for CW40, although it was less than 2.0% for the maximum case. It was concluded that the hardening induced by cold working does not cause significant variation in the failure load of cracked stainless steel pipe. (author)

  6. Behaviour of high stretch bolts in tension working as part of elements of steel structures, and their tendency to delayed fracturing

    Directory of Open Access Journals (Sweden)

    Moyseychik Evgeniy Alekseevich

    2014-12-01

    Full Text Available In the article, the author has proven that manufacturing and installation errors, as well as contact deformations of high strength bolts, if analyzed as part of tensile connections of steel structures, work in eccentric tension. In pursuance of the effective state standards, the analysis of these bolts is based on the axial tension. The author has analyzed the failure of a steel structure, caused by the fracture of eccentrically loaded bolts made of steel grade XC 42 (France, or C40 (Germany, that later followed the delayed fracturing pattern. The author provides the findings of the lab tests, whereby the above bolts were tested in the presence of an angle washer. The author has also analyzed the findings of low-temperature tests of bolts in tension. The author demonstrates that the strength of high strength bolts is driven by the material, the structure shape, and the thermal treatment pattern. Eccentric tension tests of bolts have proven that cracks emerge in the areas of maximal concentration of stresses (holes in shafts, etc. that coincide with the areas where fibers are in tension; cracks tend to follow the delayed fracturing pattern, and their development is accompanied by the deformation-induced metal heating in the fracture area. Therefore, the analysis of high strength bolts shall concentrate on the eccentric tension with account for contact-induced loads, while the tendency to delayed fracturing may be adjusted through the employment of both metallurgical and process techniques.

  7. Improvement of impact toughness by modified hot working and heat treatment in 13%Cr martensitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Srivatsa, Kulkarni, E-mail: srivatsa.kulkarni@kcssl.com; Srinivas, Perla; Balachandran, G.; Balasubramanian, V.

    2016-11-20

    Improvement of the general mechanical properties and in particular sub-zero impact toughness in a 0.2%C-13%Cr martensitic stainless steel has been explored by varying the hot deformation and heat treatment conditions. The deformation conditions include hot rolling an ingot in one case and cogging the ingot to a semis followed by hot rolling in another case. The bars made from both routes were subjected to a single hardening heat treatment at 980 °C and 1040 °C oil quenched and a double hardening heat treatment at 1040 °C followed by 980 °C oil quenched. The hardened steels were subjected to a standard two stage tempering at 710 °C followed by 680 °C. The impact toughness was found to be doubled in the cogged and rolled steel in double hardened condition. Other processing conditions show varying impact toughness levels. The toughness observed was correlated to the grain size and the carbide distribution in the matrix and the fractography features.

  8. The effect of low dose rate irradiation on the swelling of 12% cold-worked 316 stainless steel

    International Nuclear Information System (INIS)

    Allen, T. R.

    1999-01-01

    In pressurized water reactors (PWRs), stainless steel components are irradiated at temperatures that may reach 400 C due to gamma heating. If large amounts of swelling (>10%) occur in these reactor internals, significant swelling related embrittlement may occur. Although fast reactor studies indicate that swelling should be insignificant at PWR temperatures, the low dose rate conditions experienced by PWR components may possibly lead to significant swelling. To address these issues, JNC and ANL have collaborated to analyze swelling in 316 stainless steel, irradiated in the EBR-II reactor at temperatures from 376-444 C, at dose rates between 4.9 x 10 -8 and 5.8 x 10 -7 dpa/s, and to doses of 56 dpa. For these irradiation conditions, the swelling decreases markedly at temperatures less than approximately 386 C, with the extrapolated swelling at 100 dpa being around 3%. For temperatures greater than 386 C, the swelling extrapolated to 100 dpa is around 9%. For a factor of two difference in dose rate, no statistically significant effect of dose rate on swelling was seen. For the range of dose rates analyzed, the swelling measurements do not support significant (>10%) swelling of 316 stainless steel in PWRs

  9. Basic survey project for joint implementation and CDM. Comprehensive investigation into introduction of blast furnace gas-firing combined cycle power plant and energy balance review at Krivorozhsky State Integrated Steel and Ironworks 'Krivorozhstal' Steel Works

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Investigations and discussions were given on electric power generation facilities at the Krivorozhstal Steel Works in Ukraine with an aim of reducing the emission of global warming gases by means of the energy saving and petroleum substituting energy technologies. The discussions were made on the combined cycle power plant (CCPP) project that utilizes as fuel the blast-furnace gas being discharged into atmosphere. The project calls for starting the construction in fiscal 2003, and entering commercial operation in fiscal 2005. The total investment amount would be 160.65 million US dollars. In a case of producing steel and iron of 7,000 tons annually, profit would be obtained at 11.24%, which will make the project realization possible if low-interest finance can be obtained from Japan. The amount of carbon dioxide discharged from operating the facilities for eight years from 2005 to 2012 is estimated to be reduced by about 6.8 million tons. In addition, the project would contribute to enhancement in productivity of the factory by reducing the labor force. Furthermore, effect of reducing emission of sulfur dioxide can be expected. (NEDO)

  10. Psychosocial Hazard Analysis in a Heterogeneous Workforce: Determinants of Work Stress in Blue- and White-Collar Workers of the European Steel Industry.

    Science.gov (United States)

    Metzler, Yannick Arnold; Bellingrath, Silja

    2017-01-01

    The European steel industry's workforce is highly heterogeneous and consists of various occupational groups, presumably facing different psychosocial stressors. The few existing studies on the subject mainly focused on physical constraints of blue-collar workers, whereas the supposable psychosocial workload received only little research attention. This is remarkable considering the challenges associated with statutory required risk assessment of psychosocial hazards. Valid measures of hazard analysis must account for various stressors and reliably identify them, also between occupational groups. The present study, based on a sample of blue- and white-collar workers ( N  = 124) from the European steel industry, aims to provide a first insight into psychosocial stressors and strain at work in this rarely researched industrial sector. Furthermore, two well-known theoretical roadmaps in job analysis are examined regarding their utility for risk assessment in heterogeneous workforces: the German standard version of the Copenhagen Psychosocial Questionnaire (COPSOQ) and the short version of the effort-reward imbalance questionnaire. Hierarchical multiple regression analyses revealed that the COPSOQ was better suited to predict various strain indices in the present sample. Especially stressors relating to socioemotional aspects, such as work-privacy conflict, revealed a reasonable impact, indicating the need for comprehensive solutions at the organizational level instead of solutions focusing on single workplaces. To conclude, a broadly diversified and validated approach in psychosocial risk assessment is needed to adequately assess the variety of psychosocial factors at work and in different occupational groups.

  11. Nitrogen-alloyed martensitic steels

    International Nuclear Information System (INIS)

    Berns, H.

    1988-01-01

    A report is presented on initial results with pressure-nitrided martensitic steels. In heat-resistant steels, thermal stability and toughness are raised by nitrogen. In cold work steel, there is a more favourable corrosion behaviour. (orig./MM) [de

  12. A Flat Solar Collector Built from Galvanized Steel Plate, Working by Thermosyphonic Flow, Optimized for Mexican Conditions

    OpenAIRE

    Marroquín de Jesús, Á.; Olivares-Ramírez, J.M.; Ramos-López, G.A.; Pless, R.C.

    2009-01-01

    Design, construction, and testing of the thermal performance of a flat solar collector for domestic water heating are described. The absorbing plate is built from readily available materials: two sheets of galvanized steel, one of the channelled type, the other one flat, which are joined by electric welding. The absorber is connected to a 198-L thermotank, insulated with polyurethane foam. In terms of receiving surface, the prototype tested here has an area of 1.35 m², about 20% smaller than ...

  13. A Flat Solar Collector Built from Galvanized Steel Plate, Working by Thermosyphonic Flow, Optimized for Mexican Conditions

    OpenAIRE

    Á. Marroquín de Jesús; J.M. Olivares–Ramírez; G.A. Ramos–López; R.C. Pless

    2009-01-01

    Design, construction, and testing of the thermal performance of a flat solar collector for domestic water heating are described. The absorbing plate is built from readily available materials: two sheets of galvanized steel, one of the channelled type, the other one flat, which are joined by electric welding. The absorber is connected to a 198–L thermotank, insulated with polyurethane foam. In terms of receiving surface, the prototype tested here has an area of 1.35 m2, about 20% smaller than ...

  14. Effect of Heat Treatment on the Microstructure and Mechanical Properties of Nitrogen-Alloyed High-Mn Austenitic Hot Work Die Steel

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    2017-03-01

    Full Text Available In view of the requirements for mechanical properties and service life above 650 °C, a high-Mn austenitic hot work die steel, instead of traditional martensitic hot work die steel such as H13, was developed in the present study. The effect of heat treatment on the microstructure and mechanical properties of the newly developed work die steel was studied. The results show that the microstructure of the high-Mn as-cast electroslag remelting (ESR ingot is composed of γ-Fe, V(C,N, and Mo2C. V(C,N is an irregular multilateral strip or slice shape with severe angles. Most eutectic Mo2C carbides are lamellar fish-skeleton-like, except for a few that are rod-shaped. With increasing solid solution time and temperature, the increased hardness caused by solid solution strengthening exceeds the effect of decreased hardness caused by grain size growth, but this trend is reversed later. As a result, the hardness of specimens after various solid solution heat treatments increases first and then decreases. The optimal combination of hardness and austenitic grain size can be obtained by soaking for 2 h at 1170 °C. The maximum Rockwell hardness (HRC is 47.24 HRC, and the corresponding austenite average grain size is 58.4 μm. When the solid solution time is 3 h at 1230 °C, bimodality presented in the histogram of the austenite grain size as a result of further progress in secondary recrystallization. Compared with the single-stage aging, the maximum impact energy of the specimen after two-stage aging heat treatment was reached at 16.2 J and increased by 29.6%, while the hardness decreased by 1–2 HRC. After two-stage aging heat treatment, the hardness of steel reached the requirements of superior grade H13, and the maximum impact energy was 19.6% higher than that of superior grade H13, as specified in NADCA#207-2003.

  15. Microstructure and Hardness of Cold Work Vanadis 6 Steel after Subzero Treatment at −140°C

    Directory of Open Access Journals (Sweden)

    Juraj Ďurica

    2018-01-01

    Full Text Available The microstructure, phase constitution, and hardness of Cr-V ledeburitic tool steel Vanadis 6 subjected to subzero treatment at −140°C and for different soaking times have been investigated. The light microscopy, scanning electron microscopy, and X-ray diffraction have been used for microstructural investigations. The hardness has been evaluated by the Vickers method. The obtained results assist to draw that subzero treatment reduces the retained austenite amount and increases the population density of carbides, compared to conventional heat treatment. The extent of decrease in the retained austenite amount makes around 85%, and the increase in population density of small globular carbides was approximately fivefold. High compressive stresses were identified in the retained austenite, and their values follow the increase in carbide count. This makes a serious support to the theory explaining the formation of “extra” carbides as a by-product of more complete martensitic transformation. As a result of the mentioned microstructural changes, the material hardness increased from 875 ± 16 HV 10 up to 954.6 ± 14 HV 10 for conventionally quenched and SZT steels, respectively.

  16. Aircraft Steels

    Science.gov (United States)

    2009-02-19

    component usage. PH 13-8Mo is a precipitation-hardenable martensitic stainless steel combining excellent corrosion resistance with strength. Custom 465 is...a martensitic , age-hardenable stainless steel capable of about 1,724 MPa (250 ksi) UTS when peak-aged (H900 condition). Especially, this steel can...NOTES 14. ABSTRACT Five high strength steels (4340, 300M, AerMet 100, Ferrium S53, and Hy-Tuf) and four stainless steels (High Nitrogen, 13

  17. Effect of chemistry variations on the short-term rupture life and tensile properties of 20% cold-worked type 316 stainless steel

    International Nuclear Information System (INIS)

    Duncan, D.R.; Paxton, M.M.

    1977-01-01

    The effects of compositional variations on the rupture life of 20% cold-worked Type 316 stainless steel were investigated at 19-ksi (131-MPa) uniaxial tensile stress and at 1400 0 F (1033 K). Forty-nine different alloys were studied, with compositional variations from nominal in carbon, nitrogen, phosphorus, sulfur, boron, manganese, copper, silicon, molybdenum, cobalt, chromium and nickel. This alloy and cold-work level represents the duct and fuel cladding material choice for the first four core loadings of the Fast Flux Test Facility, a key element in the Liquid-Metal Fast Breeder Reactor Program. Tensile properties of four of the alloys were studied at temperatures from room temperature to 1600 0 F (1144 K). Boron, nitrogen, and molybdenum plus silicon additions significantly increased rupture life, while chromium and carbon additions decreased rupture life. Molybdenum plus silicon additions increased yield and ultimate strength and ductility at 1200 0 F (922 K) and below

  18. Comparison of surface roughness and chip characteristics obtained under different modes of lubrication during hard turning of AISI H13 tool work steel.

    Science.gov (United States)

    Raj, Anil; Wins, K. Leo Dev; Varadarajan, A. S.

    2016-09-01

    Surface roughness is one of the important parameters, which not only affects the service life of a component but also serves as a good index of machinability. Near Dry Machining, methods (NDM) are considered as sustainable alternative for workshops trying to bring down their dependence on cutting fluids and the hazards associated with their indiscriminate usage. The present work presents a comparison of the surface roughness and chip characteristics during hard turning of AISI H13 tool work steel using hard metal inserts under two popular NDM techniques namely the minimal fluid application and the Minimum Quantity Lubrication technique(MQL) using an experiment designed based on Taguchi's techniques. The statistical method of analysis of variance (ANOVA) was used to determine the relative significance of input parameters consisting of cutting speed, feed and depth of cut on the attainable surface finish and the chip characteristics. It was observed that the performance during minimal fluid application was better than that during MQL application.

  19. The influence of repeated loading on work of the steel fiber concrete drainage trays and pipes on the roads

    Directory of Open Access Journals (Sweden)

    Andriichuk Oleksandr

    2017-01-01

    Full Text Available The drainage system is one of the components of the road design. The condition of the subgrade and pavement depends on its effectiveness. The main structural elements of the drainage system on the roads are gutters and pipes. They are made of concrete or reinforced concrete. Under the influence of climatic factors and fluctuations of the vibration caused by the vehicles movement on the surface, it occurs destruction: formation of cracks, potholes, husking of concrete, destruction of protective layer of concrete, etc. It should be noted that these structures perceive the dynamic and thermal effects. The low fracture materials toughness poses the issue of searching ways of its increase. One solution of this problem is the use of dispersion-reinforced concrete gutters and pipes. The article presents the results of research strength, crack resistance and deformability of gutters and pipes using steel fiber reinforced concrete under the action of repeated loads

  20. Effect of coarse {gamma} grain size on the dynamic and static recrystallisation during hot working in microalloyed Nb and Nb-Ti steels

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, A.I.; Abad, R.; Lopez, B.; Rodriguez-Ibabe, J.M. [Centro de Estudios e Investigaciones Tecnicas de Guipuzcoa (CEIT), San Sebastian (Spain)

    1998-10-01

    The effect of coarse austenite grain size on the dynamic and static recrystallisation kinetics of two microalloyed Nb and Nb-Ti steels has been investigated in the present work. To characterize the dynamic recrystallisation behaviour of the austenite, continuous-torsion tests were carried out after the reheating of the specimen at different temperatures in the range 1000-1420 C. It has been observed that the occurrence of dynamic recrystallisation is dependent on the initial grain size and the deformation conditions (temperature and strain-rate). Decreasing values of the Zener-Hollomon parameter (Z) and grain size promotes dynamic recrystallisation. However for the coarser grain sizes no peaks appear on the flow curves above a determined value of Z. This value seems to decrease with increasing the grain size. An equation to predict the {epsilon}{sub p} peak strain for a wide range of grain sizes has been obtained for both steels. The effect of strain on the static recrystallisation of the austenite, having a large grain size, has been also studied. Interrupted-torsion tests were performed to determined the fractional softening. A quadratic dependence of t{sub 0.5} on strain has been observed, denoting a less dependence of recrystallisation on strain than proposed previously by other authors in the range of lower grain sizes. (orig.) 22 refs.

  1. Steels from materials science to structural engineering

    CERN Document Server

    Sha, Wei

    2013-01-01

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

  2. Effect of ageing on the microstructural stability of cold-worked titanium-modified 15Cr-15Ni-2.5Mo austenitic stainless steel

    International Nuclear Information System (INIS)

    Venkadesan, S.; Bhaduri, A.K.; Rodriguez, P.; Padmanabhan, K.A.

    1992-01-01

    A titanium-modified 15Cr-15Ni-2.5Mo austenitic stainless steel conforming to ASTM A 771 (UNS S 38660), commercially called Alloy D9, is being indigenously developed for application as material for the fuel clad and the hexagonal wrapper for fuel subassemblies of the Prototype Fast Breeder Reactor. As this material would be used in the cold-worked condition and would be subjected to prolonged exposure to elevated service temperatures, the effect of ageing on the microstructural stability was studied as a function of the amount of cold work. The material was given 2.5-30% prior cold work and then aged at temperatures in the range 923 to 1173 K for times ranging from 0.25 to 1000 h. Hardness measurements made before and after ageing were correlated with the Larson-Miller parameter to determine the highest stable prior cold-work level. Optical microscopy was used to study the microstructural changes. The influence of prolonged exposure for two and three years at the operating temperatures of clad and wrapper, on the elevated temperature tensile properties of a 20% prior cold-worked Alloy D9 was also studied through accelerated ageing treatments based on the present parametric approach. (orig.)

  3. On choice of tempered steels

    International Nuclear Information System (INIS)

    Govorov, A.A.; Pan'shin, I.F.; Rakhmanov, V.I.

    1978-01-01

    For the purpose of developing a graphical method for choosing structural steels, a change in the propagation work of a crack and in the critical temperature of brittleness of 40, 40Kh, 40KhN, and 40KhNM steels, was examined depending on the hardness after hardening and tempering. A diagram enabling to choose the grade of steel for making an article of known dimensions according to the preset values of its mechanical properties has been plotted. The developed selection scheme takes into account the hardenability of steels and the influence of the hardness after thermal treatment on the cold-shortness of steel

  4. [Determination of metals in waste bag filter of steel works by microwave digestion-flame atomic absorption spectrometry].

    Science.gov (United States)

    Ning, Xun-An; Zhou, Yun; Liu, Jing-Yong; Wang, Jiang-Hui; Li, Lei; Ma, Xiao-Guo

    2011-09-01

    A method of microwave digestion technique-flame atomic absorption spectrometry was proposed to determine the total contents of Cu, Zn, Pb, Cd, Cr and Ni in five different kinds of waste bag filters from a steel plant. The digestion effects of the six acid systems on the heavy metals digestion were studied for the first time. The relative standard deviation (RSD) of the method was between 1.02% and 9.35%, and the recovery rates obtained by standard addition method ranged from 87.7% to 105.6%. The results indicated that the proposed method exhibited the advantages of simplicity, speediness, accuracy and repeatability, and it was suitable for determining the metal elements of the waste bag filter. The results also showed that different digestion systems should be used according to different waste bag filters. The waste bag filter samples from different production processes had different metal elements content. The Pb and Zn were the highest in the waste bag filters, while the Cu, Ni, Cd and Cr were relatively lower. These determination results provided the scientific data for further treatment and disposal of the waste bag filter.

  5. The effect of working time on the displacement of Biodentine™ beneath prefabricated stainless steel crown: a laboratory study.

    Science.gov (United States)

    Dawood, Alaa E; Manton, David J; Parashos, Peter; Wong, Rebecca H K

    2016-11-01

    To investigate the displacement of Biodentine ™ following cementation of stainless steel crowns (SSC) with glass-ionomer cement (GIC) on plastic deciduous teeth prepared for pulpotomy. Twenty plastic teeth with prepared occlusal cavities were divided into four groups and had Biodentine ™ placed as a mock pulpotomy agent. The pulp chamber was filled with freshly mixed Biodentine ™ then a GIC-loaded SSC was seated on the tooth using a standardized seating force for periods of: 1 min (Group 1); 2 min (Group 2), 3 min (Group 3) and 6 min (Group 4) after mixing. After 24 h at 37°C and 90% humidity, the crowns were sectioned mesio-distally and standardized digital photographs taken. Image analysis software was used to determine the ratio of the surface area of displaced Biodentine ™ relative to the surface area of the pulp chamber. The thinnest section of the remaining Biodentine ™ was measured. The lowest values of Biodentine ™ displacement and the highest values of remaining Biodentine ™ thickness were associated with Group 4. There were no significant differences between the results in Group 3 and Group 4. Within the limitations of this in vitro study, a GIC-loaded SSC can be seated on Biodentine ™ placed into a pulp chamber 3 min after mixing. © 2015 Wiley Publishing Asia Pty Ltd.

  6. A Flat Solar Collector Built from Galvanized Steel Plate, Working by Thermosyphonic Flow, Optimized for Mexican Conditions

    Directory of Open Access Journals (Sweden)

    Á. Marroquín de Jesús

    2009-07-01

    Full Text Available Design, construction, and testing of the thermal performance of a flat solar collector for domestic water heating are described. The absorbing plate is built from readily available materials: two sheets of galvanized steel, one of the channelled type, the other one flat, which are joined by electric welding. The absorber is connected to a 198–L thermotank, insulated with polyurethane foam. In terms of receiving surface, the prototype tested here has an area of 1.35 m2, about 20% smaller than comparable copper–tube–based collectors offered in the market. Temperature measurements conducted over a 30–day period gave values which were a few degrees lower than the theoretically calculated water temperatures. Momentary thermal efficiency values between 35% and 77% were observed. The water temperature achieved in the tank at the end of the day aver ages 65°C in winter weather conditions in the central Mexican highland. This design of solar water heater is well suited to Mexican conditions, as it makes use of the high local intensity of the solar radiation, and as the channel shape of the ducts minimizes bursting during the rare occurrences of freezing temperatures in the region; it also has the advantage of being manufacturable at low cost from simple materials.

  7. Effect of cold working on the corrosion resistance of JPCA stainless steel in flowing Pb–Bi at 450 °C

    International Nuclear Information System (INIS)

    Rivai, Abu Khalid; Saito, Shigeru; Tezuka, Masao; Kato, Chiaki; Kikuchi, Kenji

    2012-01-01

    Development of a high performance proton beam window material is one of the critical issues for the deployment of the accelerator-driven transmutation system (ADS) with liquid Pb–Bi eutectic as a spallation target and coolant. In the present study, we applied 20% cold work treatment to JPCA austenitic stainless steel and investigated it from the corrosion behavior viewpoint. The corrosion test of 20% cold-worked JPCA SS has been carried in the JLBL-1 (JAEA Lead–Bismuth Loop-1) apparatus. The maximum temperature, the temperature difference, the flow velocity and the exposure time of the liquid Pb–Bi were 450 °C, 100 °C, 1 m/s, and 1000 h, respectively. For comparison analysis, JPCA SS without cold working was also tested in the same time and conditions with the 20% cold-worked JPCA SS. The results showed a different corrosion behavior between the JPCA SS without and with cold working. As for the JPCA SS without cold working, Pb–Bi penetrated into the matrix through a ferrite layer which was formed because of constituent metals dissolution from the matrix into Pb–Bi. As for the 20% cold-worked JPCA SS, dissolution attack occurred only partially and formed localized superficial pitting corrosion. It was found that the different corrosion behavior occurred because the cold working induced a structure transformation from γ-austenite to α′-martensite and affected the corrosion resistance of the JPCA SS in flowing Pb–Bi at 450 °C.

  8. Application of processing maps in the optimization of the parameters of a hot working process. Part 2. Processing maps of a microalloyed medium carbon steel

    International Nuclear Information System (INIS)

    Al Omar, A.; Cabrera, J.M.; Prado, J.M.

    1997-01-01

    Part 1 of this work presents a revision of the general characteristics of the so called dynamic materials model on which processing maps are developed. In this part following the methodology described in part 1, processing maps of a microalloyed medium carbon steel are developed over a temperature range varying from 900 to 1.150 degree centigree at different true strain rates ranging from 10''-4 to 10s''-1. The analysis of these maps revealed a domain of dynamic recrystallization centred at about 1.1.50 degree centigree and strain rate 10 s''-1 and a domain of dynamic recovery centred at 900 degree centigree and 0,1 s''-1. (Author) 20 refs

  9. The influence of temperature on low cycle fatigue behavior of prior cold worked 316L stainless steel (II) : life prediction and failure mechanism

    International Nuclear Information System (INIS)

    Hong, Seong Gu; Yoon, Sam Son; Lee, Soon Bok

    2003-01-01

    Tensile and low cycle fatigue tests on prior cold worked 316L stainless steel were carried out at various temperatures from room temperature to 650 deg. C. Fatigue resistance was decreased with increasing temperature and decreasing strain rate. Cyclic plastic deformation, creep, oxidation and interactions with each other are thought to be responsible for the reduction in fatigue resistance. Currently favored life prediction models were examined and it was found that it is important to select a proper life prediction parameter since stress-strain relation strongly depends on temperature. A phenomenological life prediction model was proposed to account for the influence of temperature on fatigue life and assessed by comparing with experimental result. LCF failure mechanism was investigated by observing fracture surfaces of LCF failed specimens with SEM

  10. Effect of cold work on CO sub 2 corrosion behavior of 13% Cr (420 type) stainless steel in brine medium with and without addition of sodium sulphide

    International Nuclear Information System (INIS)

    Akram Ali Agil; Azmi Rahmat; Suraj Bhan

    1996-01-01

    Cold work introduces residual stresses and increases internal stored energy. Plastic deformation also causes slip steps on the surface. All these factors effect corrosion rate as corrosion is controlled by surface reaction. The residual stresses are caused by inhomogeneous deformation in cold rolling and are maximum at low deformation and then decrease as the samples get thinner on further rolling. In the absence of CO sub 2 the corrosion rates are found relatively low in brine solution with or without addition of Na sub 2 S, with only slight variation with % total deformation. However simultaneous presence of CO sub 2 and Na sub 2 S has synergic effect increasing the corrosion rate appreciably. Presence of sulphur is also found to increase the pitting tendency in the steel

  11. Investigation of the fabrication process of hot-worked stainless-steel and Mo sheathed PbMo6 S8 wires

    International Nuclear Information System (INIS)

    Yamasaki, H.; Kimura, Y.

    1988-01-01

    Stainless-steel and Mo sheathed PbMo 6 S 8 wires have been fabricated by hot working from modified PbS, Mo, and MoS 2 mixed powders which were prepared by reacting Pb, Mo, and S at 530 0 C. Critical current densities were investigated for different preparation conditions, and it is revealed that obtaining continuous current path between PbMo 6 S 8 grains is the most important factor to achieve high critical current density. The J/sub c/ value of 2.8 x 10 4 Acm 2 (8 T), 7.8 x 10 3 Acm 2 (15 T), and 1.3 x 10 3 Acm 2 (23 T) was observed for the PbMo 6 S/sub 7.0/ wire heat treated at 700 0 C.copic

  12. Analysis of elevated temperature flow and work hardening behaviour of service-exposed 2.25Cr-1Mo steel using Voce equation

    International Nuclear Information System (INIS)

    Girish Shastry, C.; Mathew, M.D.; Bhanu Sankara Rao, K.; Mannan, S.L.

    2004-01-01

    The Voce equation was used to model the tensile flow and work-hardening behaviour of a service-exposed 2.25Cr-1Mo steel. The applicability of Voce parameters obtained from the fit to experimental true stress-true strain datasets for estimating the validity of the fit was examined. The Voce equation was found to model the stress-strain curve closely. The Voce parameter n v was correlated to the underlying dislocation activities. It was found that the values of Voce parameters at various temperatures and strain rates can be used to infer the operating recovery mechanism during stage III hardening. A low absolute value of n v is indicative of recovery by cross-slip, whereas the high temperature transition to climb or sub-boundary migration driven recovery is accompanied by an increase in the value of n v

  13. Comparative tensile flow and work hardening behaviour of thin section and forged thick section 9Cr–1Mo ferritic steel in the framework of Voce equation and Kocks–Mecking approach

    International Nuclear Information System (INIS)

    Choudhary, B.K.; Rao Palaparti, D.P.

    2012-01-01

    Detailed analysis indicated that true stress (σ)-true plastic strain (ε) and work hardening behaviour of 9Cr–1Mo steel in two different forms, i.e. 20 mm plate and thick section tubeplate forging can be adequately described by Voce equation and Kocks–Mecking approach in the temperature range 300–873 K. The steel exhibited two-stage work hardening in the variations of instantaneous work hardening rate (θ = dσ/dε) and θσ with stress. The variations in σ–ε, work hardening parameters, θ–σ and θσ–σ with temperature exhibited three distinct temperature regimes. Good correlations between the predicted tensile properties using Voce equation and the respective experimental values along with analogy between Voce equation and Kocks–Mecking approach have been demonstrated for the steel. The differences in σ–ε, work hardening parameters, θ–σ and θσ–σ observed between plate and tubeplate forging have been ascribed to the effects associated with initial microstructures for the two product forms of the steel.

  14. Life after Steel

    Science.gov (United States)

    Mangan, Katherine

    2013-01-01

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

  15. `Construction work for 1 raw material physical improvement measures` for Nippon Steel Corporation; Shinnihon Seitetsu (kabu) Kimitsu seitetsusho muke 1 genryo taishitsu kaizen taisaku koji

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-10

    Meidensha Corporation delivered electrical components to Nippon Steel Corporation for its physical improvement program. At the raw material transportation facility of Kimitsu Works, construction work for physical improvement measures was carried out aiming at the enhancement of productivity of the sintering process and the rationalization of materials flow and equipment in the yard. Meidensha Corporation delivered electrical apparatuses such as conveyer driving components and an overall operation monitor/control unit, performed improvement on the instrument boards that were already in existence, and thereby realized remotely controlled automatic operation from the raw materials center and an overall operation monitor/control function. The important control devices are a conveyer motor, a motor operating board, three sets of overall conveyer controlling PCs (UNISEQUE SB6000), an auxiliary relay board, a CRT-aided monitor/control unit, a mover trunk setting board, a work site operation appliance/detector, a modified operation/monitor board and an automatic broadcasting unit. The CRT-aided monitor/control unit (MEIDACS-BCC) monitors and controls the operation of the facility as a whole, serving as the axis of raw materials transportation control. Load optimization is accomplished by the addition of the overall conveyer control function. (NEDO)

  16. Effect of particle morphology and microstructure on strength, work-hardening and ductility behaviour of ODS-(7-13)Cr steels

    International Nuclear Information System (INIS)

    Preininger, D.

    2004-01-01

    The effect of particle morphology and grain refinement to the nanometer scale on strength, work-hardening and tensile ductility of reduced activation ODS-(7-13)Cr steels has been modelled with a dependence on deformation temperature (T=RT-700 deg. C) and a superimposed irradiation hardening. The Orowan model predictions describe as the upper limit the observed particle strengthening of various ODS-(7-13)Cr-(≤0.5 wt% yttria) steels. An optimum particle size d p * congruent with 7-22 nm (f v =0.004-0.05) and strength, together with a lower limiting ultra-fine grain size d K,c ≥90 nm result in maximum uniform ductility increase by grain refinement and dispersion hardening (DIGD). Optimum size d p * increases with increasing particle volume fraction f v and deformation temperature and decreases with irradiation hardening and grain refinement. The region of DIGD is limited to achieve a critical strength σ L corresponding to a critical particle volume fraction f v,c and grain size d K,c , above which uniform strain becomes limited by the strong drop of fracture strain. Grain refinement and irradiation hardening decrease σ L , f v,c and increase d K,c . In accordance with experimental results of ODS-Eurofer, nominal uniform strain increases with increasing f v by about ε u,n =B e +A e lnf v , most strongly around 300 deg. C, but weakly at the 600 deg. C minimum. The strong ductility increase above 600 deg. C results from a reduction of dislocation annihilation and structural recovery of strength. At T K,c for lower f v toward a saturation value which increases with increasing ratio of shear modulus to Hall-Petch constant. The enhanced uniform ductility at T≥300 deg. C is otherwise strongly decreased by grain refinement, more pronounced at lower f v and for strengths above σ L

  17. On the influence of cold work on the oxidation behavior of some austenitic stainless steels: High temperature oxidation

    NARCIS (Netherlands)

    Langevoort, J.C.; Fransen, T.; Gellings, P.J.

    1984-01-01

    AISI 304, 314, 321, and Incoloy 800H have been subjected to several pretreatments: polishing, milling, grinding, and cold drawing. In the temperature range 800–1400 K, cold work improves the oxidation resistance of AISI 304 and 321 slightly, but has a relatively small negative effect on the

  18. Relationship between swelling and irradiation creep in cold worked PCA stainless steel to 178 DPA at∼400 degrees C

    International Nuclear Information System (INIS)

    Toloczko, M.B.; Garner, F.A.

    1993-01-01

    At 178 dpa and ∼400 degrees C, the irradiation creep behavior of 20% cold-worked PCA has become dominated by the creep disappearance phenomenon. The total diametral deformation rate has reached the limiting value of 0.33%/dpa at the three highest stress levels. The stress-enhancement of swelling tends to camouflage the onset of creep disappearance, however

  19. Assessment of microstructure stability of cold worked Ti-modified austenitic stainless steel during aging using ultrasonic velocity measurements and correlation with mechanical properties

    International Nuclear Information System (INIS)

    Vasudevan, M.; Palanichamy, P.

    2003-01-01

    As ultrasonic velocity is sensitive to the changes in texture, it is a more reliable technique than mechanical property measurements for assessment of microstructural stability (recrystallization behaviour) of cold worked alloy where recrystallization is coupled with precipitation. Hence ultrasonic velocity measurements have been employed for studying the influence of Ti/C ratio on the microstructural stability of cold worked Ti-modified austenitic stainless steel during isochronal aging. In this alloy precipitation of TiC is known to retard recovery and recrystallization. The variation in ultrasonic velocity with aging temperature exhibited a three stage behaviour at all three frequencies employed (2, 10 and 20 MHz) and correlated well with the microstructural changes. Based on the microstructural investigations, the three stages have been identified to be recovery, progress of recrystallization and completion of recrystallization. There was one to one correspondence between the variation in the hardness, strength values and the variation in the ultrasonic velocity values as a function of aging temperature in assessing the microstructural changes, except when the interaction between the TiC precipitation and recrystallization is stronger

  20. Effect of cold work hardening on stress corrosion cracking of stainless steels in primary water of pressurized water reactors

    International Nuclear Information System (INIS)

    Raquet, O.; Herms, E.; Vaillant, F.; Couvant, T.; Boursier, J.M.

    2004-01-01

    A R and D program is carried out in CEA and EDF laboratories to investigate separately the effects of factors which could contribute to IASCC mechanism. In the framework of this study, the influence of cold work on SCC of ASSs in primary water is studied to supply additional knowledge concerning the contribution of radiation hardening on IASCC of ASSs. Solution annealed ASSs, essentially of type AISI 304(L) and AISI 316(L), are generally considered very resistant to SCC in nominal primary water. However, Constant Extension Rate Tests (CERTs), performed on cold pressed humped specimens in nominal primary water at 360 deg. C, reveal that these materials can exhibit a high SCC susceptibility: deepest cracks reach 1 mm (mean crack growth rate about 1 μm.h -1 ) and propagation is mainly intergranular for 304L and mainly transgranular for 316L. Indeed, work hardening in conjunction with high localized deformation can promote SCC. The influence of the nature of the cold work (shot peening, reaming, cold rolling, counter sinking, fatigue work hardening and tensile deformation) is investigated by means of screening CERTs performed with smooth specimens in 304L at 360 deg. C. For a given cold work hardening level, the susceptibility to crack initiation strongly depends on the cold working process, and no propagation is observed for a hardness level lower than 300 ±10 HV(0.49N). The propagation of cracks is observed only for dynamic loadings like CERT, traction/relaxation tests and crack growth rate tests performed with CT specimens under trapezoidal loading. Although crack initiation is observed for constant load and constant deformation tests, crack propagation do not seem to occur under these mechanical solicitations for 17000 hours of testing, even for hardness levels higher than 450 HV(0.49N). The mean crack growth rate increases when the hardness increases. An important R and D program is in progress to complement these results and to develop a SCC model for ASSs in

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

    DEFF Research Database (Denmark)

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

    2010-01-01

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

  2. Influence of different temperatures on the thermal fatigue behavior and thermal stability of hot-work tool steel processed by a biomimetic couple laser technique

    Science.gov (United States)

    Meng, Chao; Zhou, Hong; Zhou, Ying; Gao, Ming; Tong, Xin; Cong, Dalong; Wang, Chuanwei; Chang, Fang; Ren, Luquan

    2014-04-01

    Three kinds of biomimetic non-smooth shapes (spot-shape, striation-shape and reticulation-shape) were fabricated on the surface of H13 hot-work tool steel by laser. We investigated the thermal fatigue behavior of biomimetic non-smooth samples with three kinds of shapes at different thermal cycle temperature. Moreover, the evolution of microstructure, as well as the variations of hardness of laser affected area and matrix were studied and compared. The results showed that biomimetic non-smooth samples had better thermal fatigue behavior compared to the untreated samples at different thermal cycle temperatures. For a given maximal temperature, the biomimetic non-smooth sample with reticulation-shape had the optimum thermal fatigue behavior, than with striation-shape which was better than that with the spot-shape. The microstructure observations indicated that at different thermal cycle temperatures the coarsening degrees of microstructures of laser affected area were different and the microstructures of laser affected area were still finer than that of the untreated samples. Although the resistance to thermal cycling softening of laser affected area was lower than that of the untreated sample, laser affected area had higher microhardness than the untreated sample at different thermal cycle temperature.

  3. Tribological properties of anti-wear PVD coatings for elevated temperatures application deposited onto X37CrMoV5-1 type hot work steel

    International Nuclear Information System (INIS)

    Dobrzanski, L.A.; Polok, M.; Adamiak, M.

    2003-01-01

    The paper presents results of tribological and adhesion investigations of anti-wear PVD coatings TiN, TiN/(Ti,Al)N and CrN types deposited in ion plating PVD process onto X37CrMoV5-1 type hot work tool steel. It was found that damage mechanism during scratch test in all investigated coatings begins with multiple spallings located on the scratch edges followed by cracking and tool coatings delamination. Regarding to the coating types it can be seen different location of such damages and loads typical for them. According to this observations it can be stated that highest adhesion among investigated coating present, CrN monolayer coating and the lowest one multilayers Ti/(Ti,Al)N coating. The wear resistance was investigated by pin-on-disc method performed in room and elevated to 500 o C temperatures. It was found that the lowest wear in to fixed investigation conditions in both room and elevated temperatures shows TiN monolayer coating. Additionally one can see that TiN coatings application improve wear resistance some five times. (author)

  4. Review on Cold-Formed Steel Connections

    Science.gov (United States)

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

    2014-01-01

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

  5. Stones, Glass and Steel One Architect's journey towards understanding the impact of geology on his design work.

    Science.gov (United States)

    Guillot, R. E.

    2016-12-01

    Geological forms and materials have long served as inspiration for creativity. The earliest drawings in the caves of Lascaux were perhaps the simplest and most elegant narratives ever to link the earth and the stories of the people that inhabit it. The earth is a storytelling and inspirational tool.Ironically, in contemporary architecture, the forces that create minerals and the geology of the earth over time are the same forces that architecture seeks to overcome. Our buildings are stronger, taller and seemingly more gravity defying than ever before. They soar and hover while still being subject to the same forces that drove cathedrals and pyramids to embrace the ground and rise from it. How can the earth and its geological elements serve as inspiration for the art of architecture as well as connecting buildings with the places that they inhabit? Typically, the Architect's interest is in the narrow band of geology called topography- the earth's crust which is a relatively minor chapter in the story of the earth. This is the layer that impacts soils and bearing pressures for foundations but very little of the Architect's imagination. The human connection to the elements of the earth; the translucence, strata, color and at times the frozen sounds of the violent formation of the landforms themselves all can inform the language of architecture.Through a discussion of my work designed and built in the United States and around the World, I will share the inspiration of geology through my own architecture and the many architectural forms it takes.

  6. Ergonomic prevention of musculoskeletal disorders of maintenance workers in the steel industry : Guidelines for the optimum working height of selected maintenance operations

    NARCIS (Netherlands)

    Dul, J.; Bolijn, A.J.; Delleman, N.J.; Hildebrandt, V.H.

    1991-01-01

    In the steel industry musculoskeletal disorders are important determinants of sickness and absenteeism. Prevention of biomechanical risk is therefore important, both for industry and the workers themselves. In this research project, ergonomic guidelines have been developed to reduce high

  7. Ductility of high chromium stainless steels

    International Nuclear Information System (INIS)

    Peretyat'ko, V.N.; Kazantsev, A.A.

    1997-01-01

    Aimed to optimize the hot working conditions for high chromium stainless steels the experiments were carried in the temperature range of 800-1300 deg C using hot torsion tests and cylindrical specimens of ferritic and ferritic-martensitic steels 08Kh13, 12Kh13, 20Kh13, 30Kh13 and 40Kh13. Testing results showed that steel plasticity varies in a wide range depending on carbon content. Steels of lesser carbon concentration (08Kh13 and 12Kh13) exhibit a sharp increase in plasticity with a temperature rise, especially in the interval of 1200-1250 deg C. Steels 20Kh13 and 30Kh13 display insignificant plasticity increasing, whereas plastic properties of steel 40Kh13 increase noticeably in the range of 1000-1300 deg C. It is shown that optimal hot working conditions for specific steel must be selected with account of steel phase composition at high temperatures

  8. Modern steels for light automobiles (review)

    Science.gov (United States)

    Tikhonov, A. K.

    1994-10-01

    The article considers the directions of work at VAZ together with metallurgists of the CIS for creating highly efficient economically-alloyed and microalloyed steels; highly ductile forged steels with improved corrosion resistance coated with zinc and with good stamping, welding, and painting capacity. Steels are created for petrol tanks with aluminum-zinc coatings instead of lead, and new heat and corrosion-resistant steels are developed for automobile exhaust gas systems.

  9. Effects of cold working ratio and stress intensity factor on intergranular stress corrosion cracking susceptibility of non-sensitized austenitic stainless steels in simulated BWR and PWR primary water

    International Nuclear Information System (INIS)

    Yaguchi, Seiji; Yonezawa, Toshio

    2012-01-01

    To evaluate the effects of cold working ratio, stress intensity factor and water chemistry on an IGSCC susceptibility of non-sensitized austenitic stainless steel, constant displacement DCB specimens were applied to SCC tests in simulated BWR and PWR primary water for the three types of austenitic stainless steels, Types 316L, 347 and 321. IGSCC was observed on the test specimens in simulated BWR and PWR primary water. The observed IGSCC was categorized into the following two types. The one is that the IGSCC observed on the same plane of the pre-fatigue crack plane, and the other is that the IGSCC observed on a plane perpendicular to the pre-fatigue crack plane. The later IGSCC fractured plane is parallel to the rolling plane of a cold rolled material. Two types of IGSCC fractured planes were changed according to the combination of the testing conditions (cold working ratio, stress intensity factor and simulated water). It seems to suggest that the most susceptible plane due to fabrication process of materials might play a significant role of IGSCC for non-sensitized cold worked austenitic stainless steels, especially, in simulated PWR primary water. Based upon evaluating on the reference crack growth rate (R-CGR) of the test specimens, the R-CGR seems to be mainly affected by cold working ratio. In case of simulated PWR primary water, it seems that the effect of metallurgical aspects dominates IGSCC susceptibility. (author)

  10. CHARACTERIZATION OF NEW TOOL STEEL FOR ALUMINUM EXTRUSION DIES

    OpenAIRE

    José Britti Bacalhau; Fernanda Moreno Rodrigues; Rafael Agnelli Mesquita

    2014-01-01

    Aluminum extrusion dies are an important segment of application on industrial tools steels, which are manufactured in steels based on AISI H13 steel. The main properties of steels applied to extrusion dies are: wear resistance, impact resistance and tempering resistance. The present work discusses the characteristics of a newly developed hot work steel to be used on aluminum extrusion dies. The effects of Cr and Mo contents with respect to tempering resistance and the Al addition ...

  11. Ecological situation at the coke plant of the Nizhnii Tagil Integrated Iron and Steel Works (according to data from an expert commission of Gosstroi USSR)

    International Nuclear Information System (INIS)

    Filippov, B.S.

    1990-01-01

    A main source of pollution is the Nizhnii Tagil Integrated Iron and Steel Works (NTMK), whose share in the total emissions of harmful substances is very significant. Thus, in 1987 the mean annual dust content in the atmosphere of the city surpassed the maximum admissible concentrations 1.3 times, phenol 2 times, ammonia 2.5 times, benzopyrene 6 times. In 1988 an even higher content of harmful substances was noted. Reconstruction of the coke plant now underway has been called upon to ensure a significant improvement in the ecological conditions together with an overall increase in its technical level. Restoration of the existing capacity of the coke batteries at domestic coke plants is being accomplished according to two variants: first - relining of the batteries with retention of the existing dimensions or with a slight very limited increase, with modernization of the designs of the ovens and chemical departments, and also machines and equipment (technical refitting); second - withdrawal from operation of the existing batteries and construction of new higher capacity coke batteries in the plant area (reconstruction). From the standpoint of ecology and economy of capital investment it would be more expedient to restore capacity at NTMK according to the first variant. However, restoration here is being carried out according to the second variant with construction of coke batteries 9 and 10 in a new area with dry coke quenching. There are plans to decommission batteries 1-4. An analysis is given of the sources of pollution from the coke plant and measures are defined to reduce pollutants

  12. The Work Softening by Deformation-Induced Disordering and Cold Rolling of 6.5 wt pct Si Steel Thin Sheets

    Science.gov (United States)

    Wang, Xianglong; Li, Haoze; Zhang, Weina; Liu, Zhenyu; Wang, Guodong; Luo, Zhonghan; Zhang, Fengquan

    2016-09-01

    As-cast strip of 6.5 wt pct Si steel was fabricated by twin-roll strip casting. After hot rolling at 1323 K (1050 °C), thin sheets with the thickness of 0.35 mm were produced by warm rolling at 373 K (100 °C) with rolling reductions of 15, 25, 35, 45, 55, and 65 pct. Influence of warm rolling reduction on ductility was investigated by room temperature bending test. The measurement of macro-hardness showed that "work softening" could begin when the warm rolling reduction exceeded 35 pct. The room temperature ductility of the thin sheets gradually increased with the increase of warm rolling reductions, and the plastic deformation during bending began to form when the warm rolling reduction was greater than 45 pct, the 65 pct rolled thin sheet exhibited the maximum plastic deformation of about 0.6 pct during bending at room temperature, with a few small dimples having been observed on the fracture surfaces. B2-ordered domains were formed in the 15, 25, 35, 45, and 55 pct rolled specimens, and their average size decreased with the increase of warm rolling reductions. By contrast, no B2-ordered domain could be found in the 65 pct rolled specimen. It had been observed that large-ordered domains could be split into several small parts by the slip of partial super-dislocations during warm rolling, which led to significant decrease of the order degree to cause the phenomenon of deformation-induced disordering. On the basis of these results, cold rolling schedule was developed to successfully fabricate 0.25-mm-thick sheets with good surface qualities and magnetic properties from warm rolled sheets.

  13. Irradiation embrittlement of pressure vessel steels

    International Nuclear Information System (INIS)

    Brumovsky, M.; Vacek, M.

    1975-01-01

    A Standard Research Programme on Irradiation Embrittlement of Pressure Vessel Steels was approved by the Coordinating Meeting on the 12th May 1972 at the Working Group on Engineering Aspects of Irradiation Embrittlement of Pressure Vessel Steels. This Working Group was set up by the International Atomic Energy Agency in Vienna. Seven countries with their research institutes agreed on doing irradiation experiments according to the approved programme on steel A533 B from the U.S. HSST Programme. The Czechoslovak contribution covering tensile and impact testing of non-irradiated steel and steel irradiated at 280degC to 1.3 x 10 23 n/m 2 (E above 1 MeV) is presented in this report. As an additional part the same set of experiments was carried out on two additional steels - A 542 and A 543, made in SKODA Works for comparison of their irradiation embrittlement and hardening with A533 B steel. (author)

  14. Tool steels

    DEFF Research Database (Denmark)

    Højerslev, C.

    2001-01-01

    On designing a tool steel, its composition and heat treatment parameters are chosen to provide a hardened and tempered martensitic matrix in which carbides are evenly distributed. In this condition the matrix has an optimum combination of hardness andtoughness, the primary carbides provide...... resistance against abrasive wear and secondary carbides (if any) increase the resistance against plastic deformation. Tool steels are alloyed with carbide forming elements (Typically: vanadium, tungsten, molybdenumand chromium) furthermore some steel types contains cobalt. Addition of alloying elements...... serves primarily two purpose (i) to improve the hardenabillity and (ii) to provide harder and thermally more stable carbides than cementite. Assuming proper heattreatment, the properties of a tool steel depends on the which alloying elements are added and their respective concentrations....

  15. Cold formability of steels

    International Nuclear Information System (INIS)

    Lafond, G.; Leclerq, G.; Moliexe, F.; Namdar, R.; Roesch, L.; Sanz, G.

    1977-01-01

    This work was essentially aimed to the study of the following three questions. Is it possible to assess the cold formability of steels using simple material properties as criteria. What values of mechanical properties can one expect to reach in cold formed parts. Are there simple ways of characterizing the speroidization treatments carried out on steels before cold forming operations. The present report describes the results obtained during this investigation. It is logically divided into three separate parts. Experimental study of cold formability in wire drawing. Influence of metallurgical variables on mechanical properties of high carbon cold drawn wires. Contribution to the study of characterization methods of cold forming steels subjected to a spheroidization heat treatment

  16. Steels for nuclear power. I

    International Nuclear Information System (INIS)

    Bohusova, O.; Brumovsky, M.; Cukr, B.; Hatle, Z.; Protiva, K.; Stefec, R.; Urban, A.; Zidek, M.

    1976-01-01

    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

  17. Cold-formed steel design

    CERN Document Server

    Yu, Wei-Wen

    2010-01-01

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

  18. Hegelian Steel

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    2015-01-01

    Even in our globalized world the notion of national economies remain incredibly strong, just as a considerable part of the literature on transnational governance and globalization continue to rely on a zero-sum perspective concerning the relationship between the national and the transnational. De...... of the European steel industry....

  19. Investigation and working out of criteria for increasing the life time of heat-resistant steels for long-service in power plants

    International Nuclear Information System (INIS)

    1985-01-01

    In a Soviet-Swedish co-operative project extrapolation of creep rupture strength has been performed for a 12% Cr steel and a titanium stabilized 18% Cr 12% Ni steel. One Soviet and one Swedish data set for each steel was studied. This investigation showed that a fully automatized analysis procedure made it possible to study more methods and more variants of these methods, and that the results obtained had a high reproducibility. One less satisfactory property was that mathematically correct but physically unreasonable results could not be detected and rejected at an early stage in the analysis. Comparisons between a Soviet physically based method and time-temperature parameter methods showed that the latter as a rule described the actual creep behaviour better due to a more flexible mathematical form. The commonly used measure of extrapolation accuracy, the standard in log(time), was studied in careful analyses of the Swedish data, in which it was found that the correlation between extrapolation accuracy and standard deviation was poor or even negative. Since no better measure was found, and no single method could be selected as being better than the others, the average results for several methods were adopted instead, thus leveling out any less desirable effects of the methods not being suited for the studied data set. (author)

  20. Effects of Deep Cryogenic Treatment on the Wear Resistance and Mechanical Properties of AISI H13 Hot-Work Tool Steel

    Science.gov (United States)

    Çiçek, Adem; Kara, Fuat; Kıvak, Turgay; Ekici, Ergün; Uygur, İlyas

    2015-11-01

    In this study, a number of wear and tensile tests were performed to elucidate the effects of deep cryogenic treatment on the wear behavior and mechanical properties (hardness and tensile strength) of AISI H13 tool steel. In accordance with this purpose, three different heat treatments (conventional heat treatment (CHT), deep cryogenic treatment (DCT), and deep cryogenic treatment and tempering (DCTT)) were applied to tool steel samples. DCT and DCTT samples were held in nitrogen gas at -145 °C for 24 h. Wear tests were conducted on a dry pin-on-disk device using two loads of 60 and 80 N, two sliding velocities of 0.8 and 1 m/s, and a wear distance of 1000 m. All test results showed that DCT improved the adhesive wear resistance and mechanical properties of AISI H13 steel. The formation of small-sized and uniformly distributed carbide particles and the transformation of retained austenite to martensite played an important role in the improvements in the wear resistance and mechanical properties. After cleavage fracture, the surfaces of all samples were characterized by the cracking of primary carbides, while the DCT and DCTT samples displayed microvoid formation by decohesion of the fine carbides precipitated during the cryo-tempering process.

  1. Constitutive Relationship Modeling and Characterization of Flow Behavior under Hot Working for Fe–Cr–Ni–W–Cu–Co Super-Austenitic Stainless Steel

    Directory of Open Access Journals (Sweden)

    Li-Chih Yang

    2015-09-01

    Full Text Available The hot deformation behavior of a Fe–22Cr–25Ni–3.5W–3Cu–1.5Co super-austenitic stainless steel was investigated using isothermal compression tests with a wide range of temperatures (1173–1373 K and strain rates (0.1–10 s−1. The results showed that all the flow curves gradually turned to balanced stress state without notable peak stress characteristics during the entire deformation, which indicated that the dynamic recovery behavior played a main restoration mechanism in the steel. Modeling constitutive equations relating to the temperature, strain rate and flow stress were proposed to determine the materials constants and activation energy necessary for deformation. In order to give the precise predicted values of the flow behavior, the influence of strain was identified using polynomial functions. The relationship of flow stress, temperature and strain rate was represented by the Zener-Hollomon parameter including the Arrhenius term. The predicted results validated that the developed constitutive equations can describe high temperature flow behavior well. Furthermore, a modified Zener-Hollomon parameter map of the studied steel was developed to clarify the restoration mechanism based on the constitutive modeling data and microstructural observation.

  2. Steel containment buckling

    International Nuclear Information System (INIS)

    Bennett, J.G.; Fly, G.W.; Baker, W.E.

    1984-01-01

    The Steel Containment Buckling program is in its fourth phase of work directed at the evaluation of the effects of the structural failure mode of steel containments when the membrane stresses are compressive. The structural failure mode for this state of stress is instability or buckling. The program to date has investigated: (1) the effect on overall buckling capacity of the ASME area replacement method for reinforcing around circular penetrations; (2) a set of benchmark experiments on ring-stiffened shells having reinforced and framed penetrations; (3) large and small scale experiments on knuckle region buckling from internal pressure and post-buckling behavior to failure for vessel heads having torispherical geometries; and (4) buckling under time-dependent loadings (dynamic buckling). The first two investigations are complete, the knuckle buckling experimental efforts are complete with data analysis and reporting in progress, and the dynamic buckling experimental and analytical work is in progress

  3. Study on cementitious properties of steel slag

    Directory of Open Access Journals (Sweden)

    Zhu G.

    2013-01-01

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

  4. Modern trends in increasing the quality of the steels intended for cutting and metal-working tools: I. Improvement of granule metallurgy processes

    Science.gov (United States)

    Belyanchikov, L. N.

    2008-12-01

    The following new technological processes for producing fine gas-atomized powders of tool and high-speed steels with a low content of nonmetallic inclusions are considered: the process designed by Böhler Uddeholm Powder Technology (Austria) and processes involving a heated gas. In the former process, a metal is poured from a ladle with electroslag heating, and the atomizing unit consists of three injectors. A new process of producing tools from fine powders by three-dimensional printing, i.e., so-called 3D-printing, is described.

  5. Characterization of an AISI H-13 steel for work in hot; Caracterizacion del acero H-13 AISI para trabajado en caliente

    Energy Technology Data Exchange (ETDEWEB)

    Godinez, J.; Robles, E. [Instituto Nacional de Investigaciones Nucleares, Departamento de Sintesis y Caracterizacion de Materiales, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1998-07-01

    Two materials were acquired which elaborated through secondary refining processes known as electroslag refusing (ESR) and electric arc in vacuum refusing (VAR) were acquired. These materials were thermically treated, for subsequently to determine their mechanical properties in longitudinal and transversal directions with respect to rolling direction, moreover they were characterized through scanning electron microscopy and X-ray diffraction determining microstructure, carbides and non-metallic inclusions. The results of the mechanical essays allowed to evaluate the fracture toughness to this steel by the Barsom and Rolfe method. (Author)

  6. Mechanism of creep in stainless steel

    International Nuclear Information System (INIS)

    Monteiro, S.N.; Silveira, T.L.

    In the present work the creep criterions to identify the deformation mechanisms through the exponent of the strain rate versus stress relationship are presented. When applied to several stainless steels these criterions show an apparent contradiction for the proper mechanism acting at Σ/D above 10 9 /cm 2 . Microstructural aspects interfering in different manners with the fracture of these steels could be a reason for rationalizing the contradictory behavior. This is discussed in suggested deformation maps for the steels investigated [pt

  7. IMPACT STRENGTH AND FAILURE ANALYSIS OF WELDED DAMASCUS STEEL

    Directory of Open Access Journals (Sweden)

    Rastislav Mintách

    2012-01-01

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

  8. Plastic collapse load of corroded steel plates

    Indian Academy of Sciences (India)

    Keywords. Corroded steel plate; plastic collapse; FEM; rough surface. ... The main aim of present work is to study plastic collapse load of corroded steel plates with irregular surfaces under tension. Non-linear finite element method ... Department of Ocean Engineering, AmirKabir University of Technology, 15914 Tehran, Iran ...

  9. Tribological and mechanical properties of Ti/TiAlN/TiAlCN nanoscale multilayer PVD coatings deposited on AISI H11 hot work tool steel

    Energy Technology Data Exchange (ETDEWEB)

    AL-Bukhaiti, M.A., E-mail: m.albukhaiti@gmail.com [Mechanical Engineering Department, Faculty of Engineering, Sana’a University, Sana’a 12544 (Yemen); Al-hatab, K.A. [Mechanical Engineering Department, Faculty of Engineering, Sana’a University, Sana’a 12544 (Yemen); Tillmann, W.; Hoffmann, F.; Sprute, T. [Institute of Materials Engineering, Technische Universitat Dortmund, Leonhard-Euler-Str.2, 44227 Dortmund (Germany)

    2014-11-01

    Highlights: • New Ti/TiAlN/TiAlCN multilayer coating was developed. • It showed low wear rates (10{sup −16} m{sup 3}/N m), low friction coefficients (μ ∼ 0.25), and good hardness (17–20 GPa). • Friction coefficients and wear rates decrease and increase, respectively, with the increase in normal load and sliding velocity. • The coating/Al{sub 2}O{sub 3} pair showed superior wear resistance and low friction coefficient in comparison to coating/100Cr6 pair. - Abstract: A new [Ti/TiAlN/TiAlCN]{sub 5} multilayer coatings were deposited onto polished substrate AISI H11 (DIN 1.2343) steel by an industrial magnetron sputtering device. The tribological performance of the coated system was investigated by a ball-on-disk tribometer against 100Cr6 steel and Al{sub 2}O{sub 3} balls. The friction coefficients and specific wear rates were measured at various normal loads (2, 5, 8, and 10 N) and sliding velocities (0.2, 0.4, and 0.8 m/s) in ambient air and dry conditions. The phase structure, composition, wear tracks morphologies, hardness, and film/substrate adhesion of the coatings were characterized by light-microscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), 3D-surface analyzer, nanoindentation, and scratch tests. Results showed that the deposited coatings showed low wear rates in the scale of 10{sup −15} m{sup 3}/N m, low friction coefficients against 100Cr6 and Al{sub 2}O{sub 3} balls in the range of 0.25–0.37, and good hardness in the range of 17–20 GPa. Results also revealed that the friction coefficients and disc wear rates decrease and increase, respectively with the increase in normal load and sliding velocity for both coating/Al{sub 2}O{sub 3} and coating/100Cr6 sliding system. Compared with the uncoated-H11 substrate, the deposited coating exhibited superior tribological and mechanical properties. The dominant wear mechanism was abrasive wear for coating/Al{sub 2}O{sub 3} pair, while

  10. Corrosion resistant steel

    International Nuclear Information System (INIS)

    Zubchenko, A.S.; Borisov, V.P.; Latyshev, V.B.

    1980-01-01

    Corrosion resistant steel for production of sheets and tubes containing C, Mn, Cr, Si, Fe is suggested. It is alloyed with vanadium and cerium for improving tensile properties and ductility. The steel can be melted by a conventional method in electric-arc or induction furnaces. The mentioned steel is intended to be used as a substitute for nickel-bearing austenitic steels

  11. Evaluation of inelastic constitutive models under plasticity-creep interaction for 2 1/4 Cr-1 Mo steel: Results of joint work (A)

    International Nuclear Information System (INIS)

    Inoue, T.; Ohno, N.; Suzuki, A.; Igari, T.

    1987-01-01

    The authorization of constitutive models under plasticity-creep condition and life estimation methods in fatigue-creep regime is expected to be achieved from the viewpoint of design purposes of high temperature components of reactor structures. The present Subcommittee has performed the cooperative project consisting of the following two parts: (A) To review and evaluate inelastic constitutive models relevant to the material response under plasticity-creep interaction and (B) to recommend some adequate methods to estimate material life under fatigue-creep interaction by taking account of the effect of plasticity-creep interaction on the stress-strain hysteresis loops. The material treated is normalized and tempered 2 1/4 Cr-1Mo steel at 600 0 C. The part (A) plays a preliminary role for the part (B), since the constitutive models examined in the part (A) were used to describe the stress-strain hysteresis loops necessary to predict analytically the lives under fatigue-creep interaction. In the part (A), thererfore, it is important to check how accurately the constitutive models simulate the stress-strain hysteresis loops especially by taking account of the effect of plasticity-creep interaction. (orig./GL)

  12. Evaluation of inelastic constitutive models under plasticity-creep interaction for 2 1/4 Cr-1Mo steel: Results of joint work (A)

    International Nuclear Information System (INIS)

    Inoue, T.; Ohno, N.; Suzuki, A.; Igari, T.

    1987-01-01

    In order to evaluate the validity of existing inelastic constitutive models under the condition of plasticity-creep interaction, ten kinds of constitutive models were applied to sixteen bench mark problems of four categories, and the calculated results were compared with the experiments of 2 1/4Cr-1Mo steel at 600 0 C. The present bench mark project provides the following remarks: (1) The strain rate effect on the stress-strain relation can be represented, in some degree, even by a simple superposition model of classical type, and some of unified models describe the saturation of increase in flow stress with higher strain rate. (2) The characteristics of the plasticity-creep interaction were predicted by the modified superposition model as well as by unified ones in the actual calculations for the propounded problems. (3) Although the sophisticated unified constitutive models tend to give qualitatively better results, the complicated procedures in determining material parameters from the data of conventional tests need some improvements. The subcommittee has been reorganized to focus her attention in applying thus developed results under uniaxial stress state to multiaxial one, and the out-put will be expected to report in a couple of years

  13. Estimation of the Thickness and the Material Combination of the Thermal Stress Control Layer (TSCL) for the Stellite21 Hardfaced STD61 Hot Working Tool Steel Using Three-Dimensional Finite Element Analysis

    International Nuclear Information System (INIS)

    Park, Na-Ra; Ahn, Dong-Gyu; Oh, Jin-Woo

    2014-01-01

    The research on a thermal stress control layer (TSCL) begins to undertake to reduce residual stress and strain in the vicinity of the joined region between the hardfacing layer and the base part. The goal of this paper is to estimate the material combination and the thickness of TSCL for the Stellite21 hardfaced STD61 hot working tool steel via three-dimensional finite element analysis (FEA). TSCL is created by the combination of Stellite21 and STD61. The thickness of TSCL ranges from 0.5 mm to 1.5 mm. The influence of the material combination and the thickness of TSCL on temperature, thermal stress and thermal strain distributions of the hardfaced part have been investigated. The results of the investigation have been revealed that a proper material combination of TSCL is Stellite21 of 50 % and STD61 of 50 %, and its appropriate thickness is 1.0 mm

  14. Steel designers' handbook

    CERN Document Server

    Gorenc, Branko; Tinyou, Ron

    2012-01-01

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

  15. Plasma nitriding of steels

    CERN Document Server

    Aghajani, Hossein

    2017-01-01

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

  16. Optimum design of steel structures

    CERN Document Server

    Farkas, József

    2013-01-01

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

  17. Relation between superficial work hardening and SCC of an austenitic stainless steel Z3CND17-12 (AISI 316L)

    International Nuclear Information System (INIS)

    Bouzina, A.; Braham, C.; Ledion, J.

    1998-01-01

    A superficial strain hardening always leads to residual stresses. Loading during service can completely modify these stresses in a component. Without questioning the fact that compressive stresses are favourable for stress corrosion resistance, the authors show how an elastoplastic deformation on a pre-stressed material, by machining or shot peening, can be more harmful than on a non work hardened or uniformly work hardened material. (authors)

  18. Nanoprecipitation in bearing steels

    International Nuclear Information System (INIS)

    Barrow, A.T.W.; Rivera-Diaz-del-Castillo, P.E.J.

    2011-01-01

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

  19. Cathode-sputtered Ti-Zr-N-C-O base hard coatings and stability of said coatings on hard metals and working steels. Kathodenzerstaeubte Hartstoffschichten auf Basis Ti-Zr-N-C-O und deren Stabilitaet auf Hartmetall und Gebrauchsstaehlen

    Energy Technology Data Exchange (ETDEWEB)

    Boehmer, M.

    1986-02-26

    This paper deals with the examination of the metallurgical and thermal stability of the resistant material layers of titanium in connection with the substrate material influence. As substrate material were chosen: hard metal (81% WC, 12% TiC+TaC, 7% Co), high speed steel (DIN 1.3343), austenitic nickel chromium steel (X5 CrNi 18 9) and unalloyed tool steel (DIN 1.1545). The hard materials of titanium were deposited by means of cathode evaporation.

  20. Supply chain of steel industries for the nuclear power plant construction in Indonesia

    International Nuclear Information System (INIS)

    Dharu Dewi; Sahala M Lumbanraja

    2017-01-01

    Nuclear Power Plant (NPP) Construction needs steel materials for the manufacturing of heavy components and civil work construction. National industries is expected to supply steel components especially for non nuclear component needs. Supply chain of steel industries is required to know the potency of steel industries from upstream to downstream industries which can support the NPP construction sustainability. The type of steel needed in the NPP construction consist of structure steel, rebar, steel plate, etc. The aim of the study is to identify supply chain of steel industries from upstream industries to downstream industries so that they can supply steel needs in the NPP construction. The methodology used are literature review and industries survey by purposive sampling test which sent questionnaires and carrying out technical visits to the potential industries to supply steel components for NPP construction. From the analysis of the questionnaires and survey, it has been obtained that the Indonesian steel industries capable of supplying steel for construction materials of non-nuclear parts are PT. Krakatau Steel, PT. Gunung Steel Group (PT Gunung Garuda and PT. Gunung Raja Paksi), PT. Cilegon Fabricators and PT. Ometraco Arya Samanta. While steel materials for primary components with nuclear grade, such as steel materials for reactor vessels and pressure vessels, the Indonesian steel industry has not been able to supply them. Therefore, the Indonesian steel industries must improve its capability, both in raw material processing and fabrication capability in order to meet the requirements of specifications, codes and standards of nuclear grade. (author)

  1. CHARACTERIZATION OF NEW TOOL STEEL FOR ALUMINUM EXTRUSION DIES

    Directory of Open Access Journals (Sweden)

    José Britti Bacalhau

    2014-06-01

    Full Text Available Aluminum extrusion dies are an important segment of application on industrial tools steels, which are manufactured in steels based on AISI H13 steel. The main properties of steels applied to extrusion dies are: wear resistance, impact resistance and tempering resistance. The present work discusses the characteristics of a newly developed hot work steel to be used on aluminum extrusion dies. The effects of Cr and Mo contents with respect to tempering resistance and the Al addition on the nitriding response have been evaluated. From forged steel bars, Charpy impact test and characterization via EPMA have been conducted. The proposed contents of Cr, Mo, and Al have attributed to the new VEX grade a much better tempering resistance than H13, as well as a deeper and harder nitrided layer. Due to the unique characteristics, this new steel provides an interesting alternative to the aluminum extrusion companies to increase their competitiveness.

  2. Microstructural Characterization of Friction Stir Welded Aluminum-Steel Joints

    Science.gov (United States)

    2013-08-01

    Sterling, R.J. Steel, C.-O. Pettersson. “Microstructure and mechanical properties of friction stir welded SAF 2507 super duplex stainless steel.” Mater...MICROSTRUCTURAL CHARACTERIZATION OF FRICTION STIR WELDED ALUMINUM-STEEL JOINTS By ERIN ELIZABETH PATTERSON A thesis submitted in...for his work producing the dissimilar weld samples used in this study. Without his work, this project would not have been possible. I would also

  3. Prospects of structural steels

    International Nuclear Information System (INIS)

    Bannykh, O.A.

    2012-01-01

    The current state of world steel production is considered as well as the development strategy of metallurgy industry in the Russian Federation through to 2020. The main factors determining the conservation of steel as perspective material for industry are given: energy expenses on production, the well-proven recirculation technology, the capability of changing steel properties in wide range, temperature range of operation. The conclusion is made that in the immediate future steel will not lose its importance [ru

  4. Rolling Contact Fatigue Performances of Carburized and High-C Nanostructured Bainitic Steels

    OpenAIRE

    Wang, Yanhui; Zhang, Fucheng; Yang, Zhinan; Lv, Bo; Zheng, Chunlei

    2016-01-01

    In the present work, the nanostructured bainitic microstructures were obtained at the surfaces of a carburized steel and a high-C steel. The rolling contact fatigue (RCF) performances of the two alloy steels with the same volume fraction of undissolved carbide were studied under lubrication. Results show that the RCF life of the carburized nanostructured bainitic steel is superior to that of the high-C nanostructured bainitic steel in spite of the chemical composition, phase constituent, plat...

  5. Effect of Explosion Bulge Test Parameters on the Measurement of Deformation Resistance for Steel

    Science.gov (United States)

    2014-02-01

    solidification cracking in steels and stainless steels . He has also undertaken extensive work on improving the weld zone toughness of high strength steels ...Chatterjee and H. Bhadeshia, ‘TRIP-assisted steels : cracking of high carbon martensite ’, Journal of Materials Science and Technology, 2006, 22, pp. 645...649. [10] S. Chaatterjee and H.K.D.H. Bhadeshia, ‘Transformation induced plasticity assisted steels : stress or strain affected martensitic

  6. THE INFLUENCE OF POSTHEAT TREATMENT ON FERRITE REDISTRIBUTION IN DUPLEX STEELS ELECTRON BEAM WELDS

    OpenAIRE

    Zita Iždinská; František Kolenič

    2009-01-01

    The duplex stainless steel is two-phase steel with the structure composed of austenite and ferrite with optimum austenite/ferrite proportion 50%. At present, classical arc processes for welding duplex steels are generally regarded as acceptable. On the other hand electron and laser beam welding is up to now considered less suitable for welding duplex steels. The submitted work presents the results of testing various thermal conditions at welding duplex stainless steel with electron beam. It w...

  7. Trends in steel technology

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    Dual phase steels, composite products, and microalloyed steels are making inroads in the automotive industry applications for bumpers, automotive parts, bodies, mechanical parts, suspension and steering equipment and truck bumpers. New steels are also used to support solar mirrors and cells, in corrosive environments in the oil and gas industry, fusion reactors, and pressure vessels in nuclear power plants

  8. The optical metallography of some maraging steels

    International Nuclear Information System (INIS)

    Meller, E.; Pollock, J.T.A.

    1981-05-01

    The structural features of maraging steels, including those that impose limitations on strength and toughness, are briefly reviewed. Phase relationships in the iron-nickel matrix system are introduced which, in conjunction with alloy composition and heat treatment, allow the interpretation of microstructure. Details are presented of methods for revealing the microstructure of maraging steels; the prior austenite grain size following a variety of heat treatments is of special interest since excessive grain size can lead to poor ductility. These methods are illustrated with micrographs of the microstructures of MAR 350 and MAR 400 steels in the cast, solution-treated, aged and cold-worked states

  9. Noise pollution in iron and steel industry

    International Nuclear Information System (INIS)

    Bisio, G.; Piromalli, W.; Acerbo, P.

    1999-01-01

    Iron and steel industry is characterized by high energy consumption and thus present remarkable problems from the point of view of noise pollution. The aims of this paper is to examine characteristic and acoustical emissions and immisions of some fundamentals iron and steel plants with several remarks on the possible measures to reduce noise pollution. For a large integrate iron and steel system, some surveys are shown with all devices running and, in addition, comparisons are made with other surveys when the main devices were out of service owing to great maintenance works [it

  10. Relationship between swelling and irradiation creep in cold-worked PCA stainless steel irradiated to ∼178 dpa at ∼400 degrees C

    International Nuclear Information System (INIS)

    Toloczko, M.B.

    1993-09-01

    The eighth and final irradiation segment for pressurized tubes constructed from the fusion Prime Candidate Alloy (PCA) has been completed in FFTF. At 178 dpa and ∼400 degrees C, the irradiation creep of 20% cold-worked PCA has become dominated by the open-quotes creep disappearanceclose quotes phenomenon. The total diametral deformation rate has reached the limiting value of 0.33%/dpa at the three highest stress levels employed in this test. The stress-enhancement of swelling tends to camouflage the onset of creep disappearance, however, requiring the use of several non-traditional techniques to extract the creep coefficients. No failures occurred in these tubes, even though the swelling ranged from ∼20 to ∼40%

  11. Relationship between swelling and irradiation creep in cold-worked PCA stainless steel irradiated to similar 178 dpa at similar 400 C

    International Nuclear Information System (INIS)

    Toloczko, M.B.; Garner, F.A.

    1994-01-01

    The eighth and final irradiation segment for pressurized tubes constructed from the fusion Prime Candidate Alloy (PCA) has been completed in FFTF. At 178 dpa and similar 400 C, the irradiation creep of 20% cold-worked PCA has become dominated by the ''creep disappearance'' phenomenon. The total diametral deformation rate has reached the limiting value of 0.33%/dpa at the three highest stress levels employed in this test. The stress-enhancement of swelling tends to camouflage the onset of creep disappearance, however, requiring the use of several non-traditional techniques to extract the creep coefficients. No failures occurred in these tubes, even though the swelling ranged from similar 20 to 40%. ((orig.))

  12. Relationship between swelling and irradiation creep in cold-worked PCA stainless steel irradiated to similar 178 dpa at similar 400 C

    Energy Technology Data Exchange (ETDEWEB)

    Toloczko, M.B. (Department of Chemical and Nuclear Engineering, University of California, Santa Barbara, CA 93106 (United States)); Garner, F.A. (Pacific Northwest Laboratory, Richland, WA 99352 (United States))

    1994-09-01

    The eighth and final irradiation segment for pressurized tubes constructed from the fusion Prime Candidate Alloy (PCA) has been completed in FFTF. At 178 dpa and similar 400 C, the irradiation creep of 20% cold-worked PCA has become dominated by the creep disappearance'' phenomenon. The total diametral deformation rate has reached the limiting value of 0.33%/dpa at the three highest stress levels employed in this test. The stress-enhancement of swelling tends to camouflage the onset of creep disappearance, however, requiring the use of several non-traditional techniques to extract the creep coefficients. No failures occurred in these tubes, even though the swelling ranged from similar 20 to 40%. ((orig.))

  13. Weldability of Stainless Steels

    International Nuclear Information System (INIS)

    Saida, Kazuyoshi

    2010-01-01

    It gives an outline of metallographic properties of welding zone of stainless steels, generation and mechanisms of welding crack and decreasing of corrosion resistance of welding zone. It consists of seven chapters such as introduction, some kinds of stainless steels and properties, metallographic properties of welding zone, weld crack, toughness of welding zone, corrosion resistance and summary. The solidification modes of stainless steels, each solidification mode on the cross section of Fe-Cr-Ni alloy phase diagram, each solidification mode of weld stainless steels metal by electron beam welding, segregation state of alloy elements at each solidification mode, Schaeffler diagram, Delong diagram, effects of (P + S) mass content in % and Cr/Ni equivalent on solidification cracking of weld stainless steels metal, solidification crack susceptibility of weld high purity stainless steels metal, effects of trace impurity elements on solidification crack susceptibility of weld high purity stainless steels metal, ductile fracture susceptibility of weld austenitic stainless steels metal, effects of H2 and ferrite content on generation of crack of weld 25Cr-5N duplex stainless steels, effects of O and N content on toughness of weld SUS 447J1 metals, effect of ferrite content on aging toughness of weld austenitic stainless steel metal, corrosion morphology of welding zone of stainless steels, generation mechanism of knife line attack phenomenon, and corrosion potential of some kinds of metals in seawater at room temperature are illustrated. (S.Y.)

  14. The steel scrap age.

    Science.gov (United States)

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

    2013-04-02

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

  15. Thermal stability of manganese-stabilized stainless steels

    International Nuclear Information System (INIS)

    Klueh, R.L.; Kenik, E.A.

    1993-01-01

    Previous work on a series of experimental high-manganese reduced-activation austenitic stainless steels demonstrated that they have improved tensile properties relative to type 316 stainless steel in both the annealed and 20% cold-worked conditions. Steels were tested with an Fe-20Mn-12Cr-0.25C (in weight percent) base composition, to which various combinations of Ti, W, V, P, and B were added. Tensile tests have now been completed on these steels after thermal aging at 600 degrees C. Thermal stability varied with composition, but the alloys were as stable or more stable than type 316 stainless steel. the strength of the annealed steels increased slightly after aging to 5000 h, while a strength decrease occurred for the cold worked steel. In both conditions, a steel containing a combination of all the alloying elements was most stable and had the best strength after thermal aging 5000 h at 600 degrees C. Despite having much higher strength than 316 stainless steel after aging, the ductility of the strongest experimental alloy was still as good as that of 316 stainless steel

  16. A technique for predicting steel corrosion resistance

    Science.gov (United States)

    Novikov, V. F.; Sokolov, R. A.; Neradovskiy, D. F.; Muratov, K. R.

    2018-01-01

    Research works were carried out to develop a technique with the aim to increase the lifetime of steel items used in corrosive media. The possibility to monitor corrosion parameters of steel samples is analyzed on the basis of magnetic properties obtained by means of a magnetic structuroscope DIUS-1.15M designed by the Institute of Metal Physics of the Ural Branch of the Russian Academy of Sciences (IMP UB RAS).

  17. Development of commercial nitrogen-rich stainless steels

    International Nuclear Information System (INIS)

    Liljas, M.

    1999-01-01

    This paper reviews the development of nitrogen alloyed stainless steels. Nitrogen alloying of austenitic stainless steels started at an early stage and was to a large extent caused by nickel shortage. However, direct technical advantages such as increased strength of the nitrogen alloyed steels made them attractive alternatives to the current steels. It was not until the advent of the AOD (argon oxygen decarburisation) process in the late 1960s that nitrogen alloying could be controlled to such accuracy that it became successful commercially on a broader scale. The paper describes production aspects and how nitrogen addition influences microstructure and the resulting properties of austenitic and duplex stainless steels. For austenitic steels there are several reasons for nitrogen alloying. Apart from increasing strength nitrogen also improves structural stability, work hardening and corrosion resistance. For duplex steels nitrogen also has a decisive effect in controlling the microstructure during thermal cycles such as welding. (orig.)

  18. Fiscal 1999 research report. Basic research for promotion of joint implementation programs (Basic research on energy efficiency at Novolipetsk Iron and Steel Works); 1999 nendo Novolipetsk seitetsushosho energy kihon chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    A survey is conducted about whether energy efficiency improving facilities will be appropriately accommodated by the sintering process, blast furnace process, steelmaking process, and the energy process that consume energy in large quantities at the Novolipetsk Iron and Steel Works which represents Russia's steelmaking plants, which is for scouting out a project to develop into a joint implementation activity in the future. The result shows that the amount of natural gas for domestic power generators in the steelworks or the amount of power to be purchased will be reduced when large-scale exhaust heat recovery facilities are adopted. A study of the energy profile shows that there is no problem to impede the implementation of this program. Regarding the introduction of energy saving measures into the respective processes, the results of investigations conducted into the respective processes are subjected to a macroscopic study. The facilities involved include a sintering cooler exhaust heat recovery facility, hot blast furnace waste heat recovery facility, TRT (power generation by blast furnace top-pressure recovery turbines) facility, and an LDG (basic oxygen gas) recovery facility. Upon adoption of all these facilities, there will be a reduction in green effect gas (CO2) emissions of approximately 410,000 tons/year, for which a total of 20.9-billion yen will have to be invested. (NEDO)

  19. Ferritic steels for French LMFBR steam generators

    International Nuclear Information System (INIS)

    Aubert, M.; Mathieu, B.; Petrequin, P.

    1983-06-01

    Austenitic stainless steels have been widely used in many components of the French LMFBR. Up to now, ferritic steels have not been considered for these components, mainly due to their relatively low creep properties. Some ferritic steels are usable when the maximum temperatures in service do not exceed about 530 0 C. It is the case of the steam generators of the Phenix plant, where the exchange tubes of the evaporator are made of 2,25% Cr-1% Mo steel, stabilized or not by addition of niobium. These ferritic alloys have worked successfully since the first steam production in October 1973. For the SuperPhenix power plant, an ''all austenitic stainless alloy'' apparatus has been chosen. However, for the future, ferritic alloys offer potential for use as alternative materials in the evaporators: low alloys steels type 2,25% Cr-1% Mo (exchange tubes, tube-sheets, shells), or at higher chromium content type 9% Cr-2% Mo NbV (exchange tubes) or 12M Cr-1% Mo-V (tube-sheets). Most of these steels have already an industrial background, and are widely used in similar applications. The various potential applications of these steels are reviewed with regards to the French LMFBR steam generators, indicating that some points need an effort of clarification, for instance the properties of the heterogeneous ferritic/austenitic weldments

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    PURPOSE: The purpose was to examine bronchial asthma according to cumulative exposure to fume particulates conferred by stainless steel and mild steel welding through a proxy of redeemed prescribed asthma pharmaceuticals. METHODS: A Danish national company-based historical cohort of 5,303 male ever...... was estimated by combining questionnaire data on welding work with a welding exposure matrix. The estimated exposure accounted for calendar time, welding intermittence, type of steel, welding methods, local exhaustion and welding in confined spaces. Hazard ratios (HRs) with 95 % confidence intervals (CIs) were...... nonsignificant increased rate of redemption of asthma medicine was observed among high-level exposed stainless steel welders in comparison with low-level exposed welders (HR 1.54, 95 % CI 0.76-3.13). This risk increase was driven by an increase risk among non-smoking stainless steel welders (HR 1.46, 95 % CI 1...

  1. Microscopical characterization of carbon materials derived from coal and petroleum and their interaction phenomena in making steel electrodes, anodes and cathode blocks for the Microscopy of Carbon Materials Working Group of the ICCP

    Science.gov (United States)

    Predeanu, G.; Panaitescu, C.; Bălănescu, M.; Bieg, G.; Borrego, A.G.; Diez, M. A.; Hackley, Paul C.; Kwiecińska, B.; Marques, M.; Mastalerz, Maria; Misz-Kennan, M.; Pusz, S.; Suarez-Ruiz, I.; Rodrigues, S.; Singh, A. K.; Varma, A. K.; Zdravkov, A.; Zivotić, D.

    2015-01-01

    This paper describes the evaluation of petrographic textures representing the structural organization of the organic matter derived from coal and petroleum and their interaction phenomena in the making of steel electrodes, anodes and cathode blocks.This work represents the results of the Microscopy of Carbon Materials Working Group in Commission III of the International Committee for Coal and Organic Petrology between the years 2009 and 2013. The round robin exercises were run on photomicrograph samples. For textural characterization of carbon materials the existing ASTM classification system for metallurgical coke was applied.These round robin exercises involved 15 active participants from 12 laboratories who were asked to assess the coal and petroleum based carbons and to identify the morphological differences, as optical texture (isotropic/anisotropic), optical type (punctiform, mosaic, fibre, ribbon, domain), and size. Four sets of digital black and white microphotographs comprising 151 photos containing 372 fields of different types of organic matter were examined. Based on the unique ability of carbon to form a wide range of textures, the results showed an increased number of carbon occurrences which have crucial role in the chosen industrial applications.The statistical method used to evaluate the results was based on the “raw agreement indices”. It gave a new and original view on the analysts' opinion by not only counting the correct answers, but also all of the knowledge and experience of the participants. Comparative analyses of the average values of the level of overall agreement performed by each analyst in the exercises during 2009–2013 showed a great homogeneity in the results, the mean value being 90.36%, with a minimum value of 83% and a maximum value of 95%.

  2. Development of Next Generation Heating System for Scale Free Steel Reheating

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Arvind C. Thekdi

    2011-01-27

    The work carried out under this project includes development and design of components, controls, and economic modeling tools that would enable the steel industry to reduce energy intensity through reduction of scale formation during the steel reheating process. Application of scale free reheating offers savings in energy used for production of steel that is lost as scale, and increase in product yield for the global steel industry. The technology can be applied to a new furnace application as well as retrofit design for conversion of existing steel reheating furnaces. The development work has resulted in the knowledge base that will enable the steel industry and steel forging industry us to reheat steel with 75% to 95% reduction in scale formation and associated energy savings during the reheating process. Scale reduction also results in additional energy savings associated with higher yield from reheat furnaces. Energy used for steel production ranges from 9 MM Btu/ton to 16.6 MM Btu/ton or the industry average of approximately 13 MM Btu/ton. Hence, reduction in scale at reheating stage would represent a substantial energy reduction for the steel industry. Potential energy savings for the US steel industry could be in excess of 25 Trillion Btu/year when the technology is applied to all reheating processes. The development work has resulted in new design of reheating process and the required burners and control systems that would allow use of this technology for steel reheating in steel as well as steel forging industries.

  3. A comparison of the iraddiated tensile properties of a high-manganese austenitic steel and type 316 stainless steel

    International Nuclear Information System (INIS)

    Klueh, R.L.; Grossbeck, M.L.

    1984-01-01

    The USSR steel EP-838 is a high-manganese, low-nickel steel that also has lower chromium and molybdenum than type 316 stainless steel. Tensile specimens of 20%-cold-worked EP-838 and type 316 stainless steel were irradiated in the High Flux Isotope Reactor (HFIR) at the coolant temperature (approx.=50 0 C). A displacement damage level of 5.2 dpa was reached for the EP-838 and up to 9.5 dpa for the type 316 stainless steel. Tensile tests at room temperature and 300 0 C on the two steels indicated that the irradiation led to increased strength and decreased ductility compared to the unirradiated steels. Although the 0.2% yield stress of the type 316 stainless steel in the unirradiated condition was greater than that for the EP-838, after irradiation there was essentially no difference between the strength or ductility of the two steels. The results indicate that the replacement of the majority of the nickel by manganese and a reduction of chromium and molybdenum in an austenitic stainless steel of composition near that for type 316 stainless steel has little effect on the irradiated and unirradiated tensile properties at low temperatures. (orig.)

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

    International Nuclear Information System (INIS)

    Sekharbabu, R.; Rafi, H. Khalid; Rao, K. Prasad

    2013-01-01

    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

  5. Influence of inclusions on the local corrosion in steels

    International Nuclear Information System (INIS)

    Grall, L.; Mahieu, C.

    1978-01-01

    A synthesis of the work relating to the influence of inclusions on the pitting corrosion of steels, shows that pitting mainly occurs preferentially at precipitate levels, particularly sulfur precipitates. However oxidized inclusions can also cause this condition which is found on austenitic steels as well as on slightly alloyed or non alloyed steels. The method of refining as well as the morphology of inclusions can also play a part in this [fr

  6. Ultrasonic guided wave for monitoring corrosion of steel bar

    Science.gov (United States)

    Liu, Xi; Qin, Lei; Huang, Bosheng

    2018-01-01

    Steel corrosion of reinforced concrete structures has become a serious problem all over the word. In this paper, the work aims at monitoring steel corrosion using ultrasonic guided wave (UGW). Ultrasonic guided wave monitoring is a dynamic and non-destructive testing technology. The advantages of ultrasonic guided wave monitoring for reinforcement corrosion are real-time, online and continuous. In addition, it can judge the different stages of steel bar corrosion, which achieved non-destructive detection.

  7. Properties of Mo-alloyed sintered manganese steels

    International Nuclear Information System (INIS)

    Romanski, A.; Cias, A.

    1998-01-01

    Sintered alloy steels are needed for mostly PM structural parts. Powder metallurgy techniques provide a means of fabricating high quality steel parts with tailored mechanical properties. It is now possible to produce sintered steel parts with properties equal to an even superior to those of parts made by more traditional routes. Challenges arise both with the material selection and component fabrication. This work outlines the processing for high performance structural application. (author)

  8. Corrosion behavior of sensitized duplex stainless steel.

    Science.gov (United States)

    Torres, F J; Panyayong, W; Rogers, W; Velasquez-Plata, D; Oshida, Y; Moore, B K

    1998-01-01

    The present work investigates the corrosion behavior of 2205 duplex stainless steel in 0.9% NaCl solution after various heat-treatments, and compares it to that of 316L austenitic stainless steel. Both stainless steels were heat-treated at 500, 650, and 800 degrees C in air for 1 h, followed by furnace cooling. Each heat-treated sample was examined for their microstructures and Vickers micro-hardness, and subjected to the X-ray diffraction for the phase identification. Using potentiostatic polarization method, each heat-treated sample was corrosion-tested in 37 degrees C 0.9% NaCl solution to estimate its corrosion rate. It was found that simulated sensitization showed an adverse influence on both steels, indicating that corrosion rates increased by increasing the sensitization temperatures.

  9. 2169 steel waveform experiments.

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-11-01

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

  10. Steel: Price and Policy Issues

    National Research Council Canada - National Science Library

    Cooney, Stephen

    2006-01-01

    Steel prices remain at historically elevated levels. The rapid growth of steel production and demand in China is widely considered as a major cause of the increases in both steel prices and the prices of steelmaking inputs...

  11. Análisis de los riesgos musculoesqueléticos asociados a los trabajos de ferrallas: Buenas prácticas Musculoskeletal risks analysis related to steel reinforcement works: Good practices

    Directory of Open Access Journals (Sweden)

    Mónica López Alonso

    2011-12-01

    Full Text Available Los problemas musculo-esquelético suponen un 45% de las lesiones profesionales. Concretamente, los trabajadores que trabajan en las distintas actividades relacionadas con la producción y puesta en obra de la ferralla están expuestos a una gran cantidad de riesgos musculoesqueleticos. En este trabajo, se revisan detalladamente los riesgos ergonómicos de tipo físico de los ferrallistas. Este estudio permite comprobar que la normativa española en vigor desde 1997 (trasposición de la Directiva Europea sobre Seguridad y Salud en obras de construcción, no está corrigiendo los múltiples factores de riesgo musculoesqueléticos de estos trabajadores. Se propone para el análisis de dichos riesgos musculo-esqueléticos, la utilización de diversas metodologías ergonómicas. Una es el método Instituto Nacional de Seguridad e Higiene en el Trabajo para el estudio de la manipulación de cargas y, por otro lado, el método ERGO/ IBV desarrollado por el Instituto de Biomecánica de Valencia para el análisis de las posturas de movimientos repetitivos. El uso de dichas herramientas, permitirán el diseño de nuevos métodos de trabajo que disminuyan los riesgos analizados. Posteriormente, tras la identificación del elevado número de riesgos muculoesqueléticos, se definen una serie de BUENAS PRÁCTICAS para estos trabajadores expuestos a unas condiciones de trabajos muy exigentes y con escasa cultura preventiva.The MSD -musculoskeletal disorders- represent 45% of labour injuries. Specifically, construction workers involved in the different activities linked to steel reinforcement for an insitu concrete are exposed to a high rate of such injuries. This paper reviews in detail the physical risks of the iron worker, installing steel reinforcement for an insitu concrete pour. This study has revealed that the Spanish legislation, enforced since 1997 (transposing the European Directive on the implementation of minimum safety and health requirements at

  12. Embrittling effects of residual elements on steels

    International Nuclear Information System (INIS)

    Brear, J.M.; King, B.L.

    1979-01-01

    In a review of work related to reheat cracking in nuclear pressure vessel steels, Dhooge et al referred to work of the authors on the relative embrittling parameter for SA533B steels. The poor agreement when these parameters were applied to creep ductility data for SA508 class 2 lead the reviewers to conclude that the relative importance of impurity elements is a function of base alloy composition. The authors briefly describe some of their more recent work which demonstrates that when various mechanical, and other, effects are taken into consideration, the relative effects of the principal residual elements are similar, despite differing base compositions, and that the embrittling parameters derived correlate well with the data for SA Class 2 steel. (U.K.)

  13. Selective oxidation of dual phase steel after annealing at different dew points

    Science.gov (United States)

    Lins, Vanessa de Freitas Cunha; Madeira, Laureanny; Vilela, Jose Mario Carneiro; Andrade, Margareth Spangler; Buono, Vicente Tadeu Lopes; Guimarães, Juliana Porto; Alvarenga, Evandro de Azevedo

    2011-04-01

    Hot galvanized steels have been extensively used in the automotive industry. Selective oxidation on the steel surface affects the wettability of zinc on steel and the grain orientation of inhibition layer (Fe-Al-Zn alloy) and reduces the iron diffusion to the zinc layer. The aim of this work is to identify and quantify selective oxidation on the surface of a dual phase steel, and an experimental steel with a lower content of manganese, annealed at different dew points. The techniques employed were atomic force microscopy, X-ray photoelectron spectroscopy, and glow discharge optical emission spectroscopy. External selective oxidation was observed for phosphorus on steel surface annealed at 0 °C dp, and for manganese, silicon, and aluminum at a lower dew point. The concentration of manganese was higher on the dual phase steel surface than on the surface of the experimental steel. The concentration of molybdenum on the surface of both steels increased as the depth increased.

  14. The reactor vessel steels

    International Nuclear Information System (INIS)

    Bilous, W.; Hajewska, E.; Szteke, W.; Przyborska, M.; Wasiak, J.; Wieczorkowski, M.

    2005-01-01

    In the paper the fundamental steels using in the construction of pressure vessel water reactor are discussed. The properties of these steels as well as the influence of neutron irradiation on its degradation in the time of exploitation are also done. (authors)

  15. Steel Industry Wastes.

    Science.gov (United States)

    Schmidtke, N. W.; Averill, D. W.

    1978-01-01

    Presents a literature review of wastes from steel industry, covering publications of 1976-77. This review covers: (1) coke production; (2) iron and steel production; (3) rolling operations; and (4) surface treatment. A list of 133 references is also presented. (NM)

  16. Production of Austenitic Steel for the LHC Superconducting Dipole Magnets

    CERN Document Server

    Bertinelli, F; Komori, T; Peiro, G; Rossi, L

    2006-01-01

    The austenitic-steel collars are an important component of the LHC dipole magnets, operating at cryogenic temperature under high mechanical stress. The required steel, known as YUS 130S, has been specifically developed for this application by Nippon Steel Corporation (NSC), who was awarded a CERN contract in 1999 for the supply of 11 500 tonnes. In 2005 - after six years of work - the contract is being successfully completed, with final production being ensured since October 2003 by Nippon Steel & Sumikin Stainless Steel Corporation (NSSC). The paper describes the steel properties, its manufacturing and quality control process, organization of production, logistics and contract follow-up. Extensive statistics have been collected relating to mechanical, physical and technological parameters. Specific attention is dedicated to measurements of magnetic permeability performed at cryogenic temperatures by CERN, the equipment used and statistical results. Reference is also made to the resulting precision of the...

  17. Corrosion protection of steel in ammonia/water heat pumps

    Science.gov (United States)

    Mansfeld, Florian B.; Sun, Zhaoli

    2003-10-14

    Corrosion of steel surfaces in a heat pump is inhibited by adding a rare earth metal salt to the heat pump's ammonia/water working fluid. In preferred embodiments, the rare earth metal salt includes cerium, and the steel surfaces are cerated to enhance the corrosion-inhibiting effects.

  18. Use of stainless steel as structural materials in reactor cores

    International Nuclear Information System (INIS)

    Teodoro, C.A.

    1990-01-01

    Austenitic stainless steels are used as structural materials in reactor cores, due to their good mechanical properties at working temperatures and high generalized corrosion resistance in aqueous medium. The objective of this paper is to compare several 300 series austenitic stainless steels related to mechanical properties, localized corrosion resistance (SCC and intergranular) and content of delta ferrite. (author)

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

    DEFF Research Database (Denmark)

    Hald, John

    2004-01-01

    The present paper focuses in on long-term creep properties of parent material of the new 9-12%Cr creep resistant steels, P91, E911 and P92 developed for use in advanced ultrasupercritical power plants. These steels have been at the center of activities in the ECCC Working Group 3A (WG3A) "Ferriti...

  20. Competences of Engineers in the Iron and Steel Industry

    Science.gov (United States)

    Kozhevnikov, A. V.

    2017-12-01

    The article presents the results of assessment of the professional performance of engineers working in the iron and steel industry. A competence-based profile of highly-qualified professionals has been built. The study of the competences of the iron and steel industry engineers has shown that their knowledge and skills may be mobilized to solve professional tasks.

  1. Medium carbon vanadium steels for closed die forging

    International Nuclear Information System (INIS)

    Jeszensky, Gabor; Plaut, Ronald Lesley

    1993-01-01

    This work analyses the medium carbon micro alloyed vanadium potential for closed die forged production. The steels reach the mechanical resistance requests during cooling after forging, eliminating the subsequent thermal treatment. Those steels also present good fatigue resistance and machinability. The industrial scale experiments are also reported

  2. Creep-rupture, steam oxidation and recovery behaviours upon dynamic transients up to 1300 C of cold-worked 304 stainless steel tubes dedicated to nuclear core fuel cladding

    International Nuclear Information System (INIS)

    Portier, L.; Brachet, J.C.; Vandenberghe, V.; Guilbert, T.; Lezaud-Chaillioux, V.; Bernard, C.; Rabeau, V.

    2011-01-01

    An ambitious mechanical tests program was conducted on the fuel rod cladding of the CABRI facility between 2004 and 2009 to re-evaluate the cladding tubes materials behaviour. As an offspring of this major scientific investment several conclusions of interest could be drawn on the 304 stainless steel material. In particular, the specific behaviour of the materials during hypothetical and extreme 'dry-out' conditions was investigated. In such a scenario, the cladding tube materials should experience a very brief incursion at high temperatures, in a steam environment, up to 1300 C, before cladding rewetting. Some of the measurements performed in the range of interest for the safety case were on purpose developed beyond the conservatively safe domain. Some of the results obtained for these non-conventional heating rates, pressures and temperature ranges will be presented. First in order to assess the high temperature creep-rupture material behaviour under internal pressure upon dynamic transient conditions, tests have been performed on cold-worked 304 stainless cladding tubes in a steam environment, for heating rates up to 100 C*s -1 and pressure ramp rates up to 10 bar*s -1 thanks to the use of the EDGAR facility. Other tests performed at a given pressure allowed us to check the steady-state secondary creep rate of the materials in the 1100-1200 C temperature range. It was also possible to determine the rupture strength value and the failure mode as a function of the thermal and pressure loading history applied. It is worth noticing that, for very specific conditions, a surprising pure intergranular brittle failure mode of the clad has been observed. Secondly, in order to check the materials oxidation resistance of the materials, two-side steam oxidation tests have been performed at 1300 C, using the DEZIROX facility. It was shown that, thanks to the use of Ring Compression tests, the 304 cladding tube keeps significant ductility for oxidation times up to at least

  3. Ultrahigh Ductility, High-Carbon Martensitic Steel

    Science.gov (United States)

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

    2016-10-01

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

  4. Neutron irradiation creep in stainless steel alloys

    Energy Technology Data Exchange (ETDEWEB)

    Schuele, Wolfgang (Commission of the European Union, Institute for Advanced Materials, I-21020 Ispra (Vatican City State, Holy See) (Italy)); Hausen, Hermann (Commission of the European Union, Institute for Advanced Materials, I-21020 Ispra (Vatican City State, Holy See) (Italy))

    1994-09-01

    Irradiation creep elongations were measured in the HFR at Petten on AMCR steels, on 316 CE-reference steels, and on US-316 and US-PCA steels varying the irradiation temperature between 300 C and 500 C and the stress between 25 and 300 MPa. At the beginning of an irradiation a type of primary'' creep stage is observed for doses up to 3-5 dpa after which dose the secondary'' creep stage begins. The primary'' creep strain decreases in cold-worked steel materials with decreasing stress and decreasing irradiation temperature achieving also negative creep strains depending also on the pre-treatment of the materials. These primary'' creep strains are mainly attributed to volume changes due to the formation of radiation-induced phases, e.g. to the formation of [alpha]-ferrite below about 400 C and of carbides below about 700 C, and not to irradiation creep. The secondary'' creep stage is found for doses larger than 3 to 5 dpa and is attributed mainly to irradiation creep. The irradiation creep rate is almost independent of the irradiation temperature (Q[sub irr]=0.132 eV) and linearly dependent on the stress. The total creep elongations normalized to about 8 dpa are equal for almost every type of steel irradiated in the HFR at Petten or in ORR or in EBR II. The negative creep elongations are more pronounced in PCA- and in AMCR-steels and for this reason the total creep elongation is slightly smaller at 8 dpa for these two steels than for the other steels. ((orig.))

  5. A friction model for cold forging of aluminum, steel and stainless steel provided with conversion coating and solid film lubricant

    DEFF Research Database (Denmark)

    Bay, Niels; Eriksen, Morten; Tan, Xincai

    2011-01-01

    Adopting a simulative tribology test system for cold forging the friction stress for aluminum, steel and stainless steel provided with typical lubricants for cold forging has been determined for varying normal pressure, surface expansion, sliding length and tool/work piece interface temperature...

  6. Stablization of Nanotwinned Microstructures in Stainless Steels Through Alloying and Microstructural Design

    Science.gov (United States)

    2013-08-23

    Effects of carbon content, deformation, and interfacial energetics on carbide precipitation and corrosion sensitization in 304 stainless steel , Acta...Alumina- Forming Austenitic Stainless Steels Strengthened by LAves Phase and MC Carbide Precipitates , Metallurgical and Materials Transactions A...nano- precipitate engineering---of nanotwinned stainless steels . This preliminary work has provided valuable insight into the mechanisms responsible

  7. Corrosion produced failures in valves made of micro-melted stainless steel. Valve disk

    International Nuclear Information System (INIS)

    Abuin, G.; Alanis, I.; Berardo, L.

    1991-01-01

    Cast stainless steels show different metallographic structure than equivalent laminated steels where the former presents good resistance in media containing chlorides. In the present work, an analysis is made of the causes for the fracture of an AISI 316 micro-melted stainless steel disk for a valve in a cleaning agents feeding circuit in a food processing plant. (Author) [es

  8. Athermal kinetics in low alloy steels

    International Nuclear Information System (INIS)

    Leiva, Jorge A Vega; Valencia Morales, Eduardo; Villar Cociña, Ernesto; Hernández Ruiz, Jesús; Donis, Carlos

    2008-01-01

    Athermic analyses for the kinetic study of the reactions in the solid state are preferred because they consume much less experimental work time than the isothermal tests, and lead to more accurate calculations of the energies of activation of reactions that have occurred. In the present work are required conditions where you can apply the equation of speed of an athermal reaction in a low alloy in solid steel. From records of steel (AISI 1050) dilatometric triples were calculated kinetics (E, Ko, n) that characterize the reactions that occurred during the tempering of samples using different methods of iso conversion, one of which is a new modification of the method of Friedman. Also, has shown that during the formation of carbide Epsilon in the first stage of the tempering has occurred a saturation of sites, which validates the use of some methods. Finally, the orders of the reactions occurred during tempering of steel studied treatment are calculated.

  9. Seismic Behavior of Fatigue-Retrofitted Steel Frame Piers

    Directory of Open Access Journals (Sweden)

    Kinoshita K.

    2013-01-01

    Full Text Available Fatigue retrofit works have been conducted on severely fatigue damaged beam-to-column connections of existing steel frame bridge piers in Japan. It is clear that retrofit works provides additional stiffness but the significance on the seismic behavior of steel frame piers is not clear. Since fatigue retrofit works have become prevalent, the effect of fatigue retrofit works on the seismic behavior of steel frame piers need to be understood. The objective of this study is therefore to investigate these effects of the retrofit work, especially installation of bolted splices, which is the most common technique. Elasto-plastic finite element earthquake response analyses were carried out. It is shown that the existence of bolted splices may increase seismic demand on the piers when plastic hinge zone is located on the beam. In addition, longer bolted splices using low yield strength steel are proposed to overcome this problem and are shown to give beneficial effects.

  10. Martensitic Stainless Steels Low-temperature Nitriding: Dependence of Substrate Composition

    OpenAIRE

    Ferreira, Lauro Mariano; Brunatto, Silvio Francisco; Cardoso, Rodrigo Perito

    2015-01-01

    Low-temperature plasma assisted nitriding is a very promising technique to improve surface mechanical properties of stainless steels, keeping unaltered or even improving their surface corrosion resistance. During treatment, nitrogen diffuses into the steel surface, increasing its hardness and wear resistance. In the present work the nitriding process of different martensitic stainless steels was studied. As-quenched AISI 410, 410NiMo, 416 and 420 stainless steel samples were plasma nitrided a...

  11. Working hot

    International Nuclear Information System (INIS)

    Stix, G.

    1988-01-01

    The author says ''barehand'' methods, where specially trained utility workers are called in conductive suits to equalize voltage over their bodies, to maintain high-voltage transmission lines are on the rise. Utilities are building lines at higher voltages and selling more power to other utilities, making it highly inconvenient to take the lines out of service. However, some unions view the barehand work with less than enthusiasm. Touching lines energized at hundreds of thousands of volts demands flawless equipment and rigid work procedures followed to the letter. Some local unions contend that adequate safety procedures and training, and appropriate penalties for workplace negligence, should be in place before utilities may do barehand work. The author discusses some of the methods of barehand work and the equipment used, i.e. steel-mesh lineman's suit, bucket truck's boom, helicopters, and robots

  12. Iron and steel research at CENIM

    International Nuclear Information System (INIS)

    Medina, S. F.; Lopez, F.; Morcillo, M.

    2003-01-01

    In 2002 the National Centre for Metallurgical Research (CENIM) celebrated its 39th anniversary. During this time, steel has been the most studied material of all the metals and alloys researched in the different projects funded by national science and technology plans, European metallurgical research programmes, and by the iron and steel making companies who over the years have placed their trust in the research work undertaken at CENIM. Two generations of researchers have dedicated their careers to studying the different aspects of steel, from primary metallurgy considering iron ores and enrichment processes, the thermodynamics of reactions in the blast furnace and in the ladle, thermal and thermomechanical treatments, the physical metallurgy of steels, their mechanical properties, and finally their deterioration in a wide range of media of different aggressivities. CENIM maintains its commitment to iron and steel research, drawing attention to the vast amount of research work undertaken and financed within the framework of the ECSC programme since Spain joined the European Community in January 1986. (Author) 3 refs

  13. Damascus steel ledeburite class

    Science.gov (United States)

    Sukhanov, D. A.; Arkhangelsky, L. B.; Plotnikova, N. V.

    2017-02-01

    Discovered that some of blades Damascus steel has an unusual nature of origin of the excess cementite, which different from the redundant phases of secondary cementite, cementite of ledeburite and primary cementite in iron-carbon alloys. It is revealed that the morphological features of separate particles of cementite in Damascus steels lies in the abnormal size of excess carbides having the shape of irregular prisms. Considered three hypotheses for the formation of excess cementite in the form of faceted prismatic of excess carbides. The first hypothesis is based on thermal fission of cementite of a few isolated grains. The second hypothesis is based on the process of fragmentation cementite during deformation to the separate the pieces. The third hypothesis is based on the transformation of metastable cementite in the stable of angular eutectic carbide. It is shown that the angular carbides are formed within the original metastable colony ledeburite, so they are called “eutectic carbide”. It is established that high-purity white cast iron is converted into of Damascus steel during isothermal soaking at the annealing. It was revealed that some of blades Damascus steel ledeburite class do not contain in its microstructure of crushed ledeburite. It is shown that the pattern of carbide heterogeneity of Damascus steel consists entirely of angular eutectic carbides. Believe that Damascus steel refers to non-heat-resistant steel of ledeburite class, which have similar structural characteristics with semi-heat-resistant die steel or heat-resistant high speed steel, differing from them only in the nature of excess carbide phase.

  14. An internal friction peak caused by hydrogen in maraging steel

    International Nuclear Information System (INIS)

    Usui, Makoto; Asano, Shigeru

    1996-01-01

    Internal friction in hydrogen-charged iron and steel has so far been studied by a large number of investigators. For pure iron, a well-defined peak of internal friction has been observed under the cold-worked and hydrogen-charged conditions. This is called the hydrogen cold-work peak, or the Snoek-Koester relaxation, which originates from the hydrogen-dislocation interaction. In the present study, a high-strength maraging steel (Fe-18Ni-9Co-5Mo) was chosen as another high-alloy steel which is known to be very susceptible to hydrogen embrittlement. The purpose of this paper is to show a new internal friction peak caused by hydrogen in the maraging steel and to compare it with those found in stainless steels which have so far been studied as typical engineering high-alloy materials

  15. Behaviour of steels in natural environments: focus on stainless steels in natural sea water

    International Nuclear Information System (INIS)

    Feron, D.

    2005-01-01

    Corrosion behaviour of steels and alloys in natural environments is not only dependent to material parameters and environmental chemistry, but also to micro-organisms which may be there. The global approach used to investigate the behaviour of alloys in natural environments is illustrated by the work done on stainless steels in seawater. In aerated seawater, studies led to the proposal of an 'enzymatic model' based on the enzymatic catalyze of the cathodic reaction and which allows reproducing the electrochemical behaviour of stainless steels in natural seawater and the crevice corrosion phenomena observed in natural sea waters. Coupling areas under aerobic and anaerobic conditions leads to the worst situation for stainless steel behaviour: the catalysis of the cathodic reaction on aerobic exposed surfaces and the decrease of the corrosion resistance of anaerobic surfaces due to sulphides. These results lead to the concept of electro-active bio-films. (author)

  16. Spark Plasma Co-Sintering of Mechanically Milled Tool Steel and High Speed Steel Powders.

    Science.gov (United States)

    Pellizzari, Massimo; Fedrizzi, Anna; Zadra, Mario

    2016-06-16

    Hot work tool steel (AISI H13) and high speed steel (AISI M3:2) powders were successfully co-sintered to produce hybrid tool steels that have properties and microstructures that can be modulated for specific applications. To promote co-sintering, which is made difficult by the various densification kinetics of the two steels, the particle sizes and structures were refined by mechanical milling (MM). Near full density samples (>99.5%) showing very fine and homogeneous microstructure were obtained using spark plasma sintering (SPS). The density of the blends (20, 40, 60, 80 wt % H13) was in agreement with the linear rule of mixtures. Their hardness showed a positive deviation, which could be ascribed to the strengthening effect of the secondary particles altering the stress distribution during indentation. A toughening of the M3:2-rich blends could be explained in view of the crack deviation and crack arrest exerted by the H13 particles.

  17. Anisotropic densification of reference steel

    International Nuclear Information System (INIS)

    Garner, F.A.; Bates, J.F.; Gilbert, E.R.

    1975-09-01

    A correlation is presented for the densification expected during neutron irradiation of 20 percent CW 316 stainless steel cladding of FTR specification. The densification is known to be a function of time, prior heat treatment, cold work level, irradiation temperature and minor element composition. For FTR fuel pin use, the temperature and carbon composition were chosen as the only relevant variables on which to base the correlation. The densification of FTR cladding is expected to be slightly anisotropic, leading to a diameter change somewhat less than that predicted by the isotropic relationship ΔD = -D 0 /3

  18. Towards self-healing creep resistant steels

    NARCIS (Netherlands)

    Van der Zwaag, S.; Zhang, S.; Fang, H.; Bruck, E.; Van Dijk, N.H.

    2016-01-01

    We report the main findings of our work on the behaviour of binary Fe-Cu and Fe-Au model alloys designed to explore routes to create new creep resistant steels having an in-built ability to autonomously fill creep induced porosity at grain boundaries. The alloying elements were selected on the basis

  19. Structural amorphous steels

    International Nuclear Information System (INIS)

    Lu, Z.P.; Liu, C.T.; Porter, W.D.; Thompson, J.R.

    2004-01-01

    Recent advancement in bulk metallic glasses, whose properties are usually superior to their crystalline counterparts, has stimulated great interest in fabricating bulk amorphous steels. While a great deal of effort has been devoted to this field, the fabrication of structural amorphous steels with large cross sections has remained an alchemist's dream because of the limited glass-forming ability (GFA) of these materials. Here we report the discovery of structural amorphous steels that can be cast into glasses with large cross-section sizes using conventional drop-casting methods. These new steels showed interesting physical, magnetic, and mechanical properties, along with high thermal stability. The underlying mechanisms for the superior GFA of these materials are discussed

  20. Performance Steel Castings

    Science.gov (United States)

    2012-09-30

    system components to be built. Figure la shows the machine design . PSC-2012 Page 94 Glue Application Sheet Transfer Feed Elevator Figure la...Department of Defense such as cleats, ejection chutes , control arms, muzzle brakes, mortar components, clevises, tow bar clamps, ammo conveyor elements...Foundry and the members of Steel Founders’ Society of America. Abstract Weapon system designers and builders need advanced steel casting technology

  1. Processing and refinement of steel microstructure images for assisting in computerized heat treatment of plain carbon steel

    Science.gov (United States)

    Gupta, Shubhank; Panda, Aditi; Naskar, Ruchira; Mishra, Dinesh Kumar; Pal, Snehanshu

    2017-11-01

    Steels are alloys of iron and carbon, widely used in construction and other applications. The evolution of steel microstructure through various heat treatment processes is an important factor in controlling properties and performance of steel. Extensive experimentations have been performed to enhance the properties of steel by customizing heat treatment processes. However, experimental analyses are always associated with high resource requirements in terms of cost and time. As an alternative solution, we propose an image processing-based technique for refinement of raw plain carbon steel microstructure images, into a digital form, usable in experiments related to heat treatment processes of steel in diverse applications. The proposed work follows the conventional steps practiced by materials engineers in manual refinement of steel images; and it appropriately utilizes basic image processing techniques (including filtering, segmentation, opening, and clustering) to automate the whole process. The proposed refinement of steel microstructure images is aimed to enable computer-aided simulations of heat treatment of plain carbon steel, in a timely and cost-efficient manner; hence it is beneficial for the materials and metallurgy industry. Our experimental results prove the efficiency and effectiveness of the proposed technique.

  2. Nitrogen implantation in steel with an impulsive ion implanter

    International Nuclear Information System (INIS)

    Feugeas, J.N.; Gonzalez, C.O.; Hermida, J.; Nieto, M.; Peyronel, M.F.; Sanchez, G.

    1990-01-01

    This work describes the results of steel implantation with nitrogen, with a pulsed accelerator which provides a continuous ion energy spectrum giving a uniform profile of nitrogen without changing its operative conditions. (Author)

  3. Tool steel for cold worck niobium carbides

    International Nuclear Information System (INIS)

    Goldenstein, H.

    1984-01-01

    A tool steel was designed so as to have a microstructure with the matrix similar a cold work tool steel of D series, containing a dispersion of Niobium carbides, with no intention of putting Niobium in solution on the matrix. The alloy was cast, forged and heat treated. The alloy was easily forged; the primary carbide morfology, after forging, was faceted, tending to equiaxed. The hardness obtained was equivalent to the maximum hardness of a D-3 sttel when quenched from any temperature between 950 0 C, and 1200 0 , showing a very small sensitivy to the quenching temperature. (Author) [pt

  4. Thixoforming of Steels and Industrial Applications

    International Nuclear Information System (INIS)

    Ahmed, Rassili; Marc, Robelet; Regis, Bigot; Dirk, Fischer

    2007-01-01

    Thixoforming of steels becomes more and more investigated. Recent works show the economical potential of the process and lead to many industrial tests. In deed, compared to light metals, thixoformed steels open new markets and allow new designs of industrial parts taking into account, material and energy saving as well as industrial criteria such as parts quality and life.The Thixosteel consortium is developing new tools either in modelling, material study, assessment, parts design, adequate tools and equipments. Recent results and actual state of the art is presented and discussed

  5. Laser beam welding of new ultra-high strength and supra-ductile steels

    Science.gov (United States)

    Dahmen, Martin

    2015-03-01

    Ultra-high strength and supra-ductile are entering fields of new applications. Those materials are excellent candidates for modern light-weight construction and functional integration. As ultra-high strength steels the stainless martensitic grade 1.4034 and the bainitic steel UNS 53835 are investigated. For the supra-ductile steels stand two high austenitic steels with 18 and 28 % manganese. As there are no processing windows an approach from the metallurgical base on is required. Adjusting the weld microstructure the Q+P and the QT steels require weld heat treatment. The HSD steel is weldable without. Due to their applications the ultra-high strength steels are welded in as-rolled and strengthened condition. Also the reaction of the weld on hot stamping is reflected for the martensitic grades. The supra-ductile steels are welded as solution annealed and work hardened by 50%. The results show the general suitability for laser beam welding.

  6. Machinability Evaluation in Hard Milling of AISI D2 Steel

    OpenAIRE

    Gaitonde, Vinayak Neelakanth; Karnik, Sulse Ramesh; Maciel, Caio Henrique Alves; Rubio, Juan Carlos Campos; Abrão, Alexandre Mendes

    2016-01-01

    Milling of hardened steel components provides considerable benefits in terms of reduced manufacturing cost and time compared to traditional machining. Temperature variation in milling is an important factor affecting the wear of cutting tools. The poor selection of milling parameters may cause excessive tool wear and increased work surface roughness. Hence, there is a need to study the machinability aspects during milling of hardened steel components. In the present work, influence of cutting...

  7. Corrosion-resistant coating technique for oxide-dispersion-strengthened ferritic/martensitic steel

    International Nuclear Information System (INIS)

    Sakasegawa, Hideo; Tanigawa, Hiroyasu; Ando, Masami

    2014-01-01

    Oxide-dispersion-strengthened (ODS) steels are attractive materials for application as fuel cladding in fast reactors and first-wall material of fusion blanket. Recent studies have focused more on high-chromium ferritic (12-18 wt% Cr) ODS steels with attractive corrosion resistance properties. However, they have poor material workability, require complicated heat treatments for recrystallization, and possess anisotropic microstructures and mechanical properties. On the other hand, low-chromium ferritic/martensitic (8-9 wt% Cr) ODS steels have no such limitations; nonetheless, they have poor corrosion resistance properties. In our work, we developed a corrosion-resistant coating technique for a low-chromium ferritic/martensitic ODS steel. The ODS steel was coated with the 304 or 430 stainless steel, which has better corrosion resistances than the low-chromium ferritic/martensitic ODS steels. The 304 or 430 stainless steel was coated by changing the canning material from mild steel to stainless steel in the conventional material processing procedure for ODS steels. Microstructural observations and micro-hardness tests proved that the stainless steels were successfully coated without causing a deterioration in the mechanical property of the low-chromium ferritic/martensitic ODS steel. (author)

  8. Fusion welding of borated stainless steels

    International Nuclear Information System (INIS)

    Robino, C.V.; Cieslak, M.J.

    1993-01-01

    Borated austenitic stainless steels have been developed for use in the nuclear industry where storage, transport, and reprocessing of nuclear materials are required. The objective of this work is to develop appropriate joining technology for borated stainless steels based upon understanding the response of these materials to thermal processing involving melting. This understanding is being developed through the application of physical metallurgy techniques to determine the evolution of microstructure and mechanical properties within the various regions of the HAZ. Initial investigations include development of the kinetics of boride coarsening in the solid-state region of HAZ and the effect of boride coarsening on the impact properties of this region of the weld zone. Microstructures of the borated stainless steels, their response to high temperature isothermal heat treatments, and the implications of these heat treatments with respect to welding behavior will be presented

  9. Heat transfer coefficients during quenching of steels

    Energy Technology Data Exchange (ETDEWEB)

    Hasan, H.S.; Jalil, J.M. [University of Technology, Department of Electromechanical Engineering, Baghdad (Iraq); Peet, M.J.; Bhadeshia, H.K.D.H. [University of Cambridge, Department of Materials Science and Metallurgy, Cambridge (United Kingdom)

    2011-03-15

    Heat transfer coefficients for quenching in water have been measured as a function of temperature using steel probes for a variety of iron alloys. The coefficients were derived from measured cooling curves combined with calculated heat-capacities. The resulting data were then used to calculate cooling curves using the finite volume method for a large steel sample and these curves have been demonstrated to be consistent with measured values for the large sample. Furthermore, by combining the estimated cooling curves with time-temperature-transformation (TTT) diagrams it has been possible to predict the variation of hardness as a function of distance via the quench factor analysis. The work should prove useful in the heat treatment of the steels studied, some of which are in the development stage. (orig.)

  10. Nuclear energy and the steel industry

    International Nuclear Information System (INIS)

    Barnes, R.S.

    1977-01-01

    Fossil fuels represent a large part of the cost of iron and steel making and their increasing cost has stimulated investigation of methods to reduce the use of fossil fuels in the steel industry. Various iron and steel making routes have been studied by the European Nuclear Steelmaking Club (ENSEC) and others to determine to what extent they could use energy derived from a nuclear reactor to reduce the amount of fossil fuel consumed. The most promising concept is a High-Temperature Gas-Cooled Nuclear Reactor heating helium to a temperature sufficient to steam reform hydrocarbons into reducing gases for the direct reduction of iron ores. It is proposed that the reactor/reformer complex should be separate from the direct-reduction plant/steelworks and should provide reducing gas by pipeline, not only to a number of steel works but to other industrial users. The composition of suitable reducing gases and the methods of producing them from various feedstocks are discussed. Highly industrialised countries with large steel and chemical industries have shown greatest interest in the concept, but those countries with large iron-ore reserves and growing direct capacity should consider the future value of the High-Temperature Gas-Cooled Reactor as a means of extending the life of their gas reserves. (author)

  11. Compresibility and sinterability of HCx PM steel diluted with stainless steels

    Directory of Open Access Journals (Sweden)

    Elena Gordo

    2003-12-01

    Full Text Available HCx powder metallurgy steel contains in its composition high contents of Cr and C, and significant quantities of alloy elements typical of tool steels (Mo, V, W, to provide the corrosion resistance of stainless steel with wear resistance of tool steels. HCx appears to be a suitable material for applications in aggressive environments, as valve seat inserts in automotive engines. However, this steel presents a low compressibility leading to high production costs. In this work, some results carried out to improve the compressibility of HCx are presented. The way to attempt this improvement is the dilution of base material with two stainless steels, the ferritic 430LHC and the austenitic 316L. The powder mixes prepared were uniaxially pressed to study the compressibility. The sinterability was study by determining of density, hardness, transverse rupture strength (TRS and microstructural evolution after vacuum sintering at different temperatures. As a result, better compressibility is observed in the mixes although not all of them present the properties required.

  12. Electrolytic plasma processing of steel surfaces

    International Nuclear Information System (INIS)

    Bejar, M.A; Araya, R.N; Baeza, B

    2006-01-01

    The thermo-chemical treatments of steels with plasma is normally carried out in low-pressure ionized gaseous atmospheres. Among the treatments used most often are: nitruration, carburization and boronized. A plasma can also generate at atmospheric pressure. One way to produce it is with an electrochemical cell that works at a relatively high inter-electrode voltage and under conditions of heavy gas generation. This type of plasma is known as electrolytic plasma. This work studies the feasibility of using electrolytic plasma for the surface processing of steels. Two processes were selected: boronized and nitruration., for the hardening of two types of steel: one with low carbon (1020) and one with low alloy (4140). In the case of the nitruration, the 1020 steel was first aluminized. The electrolytes were aqueous solutions of borax for the boronizing and urea for the nitruration. The electrolytic plasmas were classified qualitatively, in relation with their luminosity by low, medium and high intensity. The boronizing was carried out with low intensity plasmas for a period of one hour. The nitruration was performed with plasmas of different intensities and for period of a few minutes to half an hour. The test pieces processed by electrolytic plasma were characterized by micro-hardness tests and X-ray diffraction. The maximum surface hardnesses obtained for the 1020 and 4140 steels were the following: 300 and 700 HV for the boronizing, and 1650 and 1200 HV for the nitruration, respectively. The utilization of an electrolytic plasma permits the surface processing of steels, noticeably increasing their hardness. With this type of plasma some thermo-chemical surface treatments can be done very rapidly as well (CW)

  13. Mathematical modelling and TMCP simulation for optimisation of steel behaviour

    International Nuclear Information System (INIS)

    Siwecki, T.

    2001-01-01

    Physically based mathematical models for prediction of steel behaviour and microstructure evolution in connection with thermal and thermomechanical controlled processing (TMCP) development in Swedish Institute for Metals Research are discussed. The models can be used for computer predictions of recrystallization and grain growth of austenite after deformation, precipitation or dissolution of microalloying carbonitride in austenite, flow stress during hot working, phase transformation behaviour during accelerated cooling as well as the final microstructure and mechanical properties. The database, which contains information about steel behaviour for a large number of HSLA steels, is also presented. Optimization of TMCP parameters for improving the properties of the steel are discussed in relation to the microstructure and mechanical properties. The effect of TMCP parameters (reheating temperature, rolling schedules and finish rolling temperature as well as accelerated control cooling) on steel properties was studied in laboratory scale. (author)

  14. Features of residual stresses in duplex stainless steel butt welds

    Science.gov (United States)

    Um, Tae-Hwan; Lee, Chin-Hyung; Chang, Kyong-Ho; Nguyen Van Do, Vuong

    2018-04-01

    Duplex stainless steel finds increasing use as an alternative to austenitic stainless steel, particularly where chloride or sulphide stress corrosion cracking is of primary concern, due to the excellent combination of strength and corrosion resistance. During welding, duplex stainless steel does not create the same magnitude or distribution of weld-induced residual stresses as those in welded austenitic stainless steel due to the different physical and mechanical properties between them. In this work, an experimental study on the residual stresses in butt-welded duplex stainless steel is performed utilizing the layering technique to investigate the characteristics of residual stresses in the weldment. Three-dimensional thermos-mechanical-metallurgical finite element analysis is also performed to confirm the residual stress measurements.

  15. Low-temperature creep of austenitic stainless steels

    Science.gov (United States)

    Reed, R. P.; Walsh, R. P.

    2017-09-01

    Plastic deformation under constant load (creep) in austenitic stainless steels has been measured at temperatures ranging from 4 K to room temperature. Low-temperature creep data taken from past and unreported austenitic stainless steel studies are analyzed and reviewed. Creep at cryogenic temperatures of common austenitic steels, such as AISI 304, 310 316, and nitrogen-strengthened steels, such as 304HN and 3116LN, are included. Analyses suggests that logarithmic creep (creep strain dependent on the log of test time) best describe austenitic stainless steel behavior in the secondary creep stage and that the slope of creep strain versus log time is dependent on the applied stress/yield strength ratio. The role of cold work, strain-induced martensitic transformations, and stacking fault energy on low-temperature creep behavior is discussed. The engineering significance of creep on cryogenic structures is discussed in terms of the total creep strain under constant load over their operational lifetime at allowable stress levels.

  16. Corrosion Protection of Steels by Conducting Polymer Coating

    Directory of Open Access Journals (Sweden)

    Toshiaki Ohtsuka

    2012-01-01

    Full Text Available The corrosion protection of steels by conducting polymer coating is reviewed. The conducting polymer such as polyaniline, polypyrrole, and polythiophen works as a strong oxidant to the steel, inducing the potential shift to the noble direction. The strongly oxidative conducting polymer facilitates the steel to be passivated. A bilayered PPy film was designed for the effective corrosion protection. It consisted of the inner layer in which phosphomolybdate ion, PMo12O3−40 (PMo, was doped and the outer layer in which dodecylsulfate ion (DoS was doped. The inner layer stabilized the passive oxide and the outer possessed anionic perm-selectivity to inhibit the aggressive anions such as chloride from penetrating through the PPy film to the substrate steel. By the bilayered PPy film, the steel was kept passive for about 200 h in 3.5% sodium chloride solution without formation of corrosion products.

  17. Clean steels for fusion

    International Nuclear Information System (INIS)

    Gelles, D.S.

    1995-03-01

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

  18. Steel fiber reinforced concrete

    International Nuclear Information System (INIS)

    Baloch, S.U.

    2005-01-01

    Steel-Fiber Reinforced Concrete is constructed by adding short fibers of small cross-sectional size .to the fresh concrete. These fibers reinforce the concrete in all directions, as they are randomly oriented. The improved mechanical properties of concrete include ductility, impact-resistance, compressive, tensile and flexural strength and abrasion-resistance. These uniqlte properties of the fiber- reinforcement can be exploited to great advantage in concrete structural members containing both conventional bar-reinforcement and steel fibers. The improvements in mechanical properties of cementitious materials resulting from steel-fiber reinforcement depend on the type, geometry, volume fraction and material-properties of fibers, the matrix mix proportions and the fiber-matrix interfacial bond characteristics. Effects of steel fibers on the mechanical properties of concrete have been investigated in this paper through a comprehensive testing-programme, by varying the fiber volume fraction and the aspect-ratio (Lid) of fibers. Significant improvements are observed in compressive, tensile, flexural strength and impact-resistance of concrete, accompanied by marked improvement in ductility. optimum fiber-volume fraction and aspect-ratio of steel fibers is identified. Test results are analyzed in details and relevant conclusions drawn. The research is finally concluded with future research needs. (author)

  19. Tensile behavior of irradiated manganese-stabilized stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Klueh, R.L. [Oak Ridge National Lab., TN (United States)

    1996-10-01

    Tensile tests were conducted on seven experimental, high-manganese austenitic stainless steels after irradiation up to 44 dpa in the FFTF. An Fe-20Mn-12Cr-0.25C base composition was used, to which various combinations of Ti, W, V, B, and P were added to improve strength. Nominal amounts added were 0.1% Ti, 1% W, 0.1% V, 0.005% B, and 0.03% P. Irradiation was carried out at 420, 520, and 600{degrees}C on the steels in the solution-annealed and 20% cold-worked conditions. Tensile tests were conducted at the irradiation temperature. Results were compared with type 316 SS. Neutron irradiation hardened all of the solution-annealed steels at 420, 520, and 600{degrees}C, as measured by the increase in yield stress and ultimate tensile strength. The steel to which all five elements were added to the base composition showed the least amount of hardening. It also showed a smaller loss of ductility (uniform and total elongation) than the other steels. The total and uniform elongations of this steel after irradiation at 420{degrees}C was over four times that of the other manganese-stabilized steels and 316 SS. There was much less difference in strength and ductility at the two higher irradiation temperatures, where there was considerably less hardening, and thus, less loss of ductility. In the cold-worked condition, hardening occured only after irradiation at 420{degrees}C, and there was much less difference in the properties of the steels after irradiation. At the 420{degrees}C irradiation temperature, most of the manganese-stabilized steels maintained more ductility than the 316 SS. After irradiation at 420{degrees}C, the temperature of maximum hardening, the steel to which all five of the elements were added had the best uniform elongation.

  20. Simple Heat Treatment for Production of Hot-Dip Galvanized Dual Phase Steel Using Si-Al Steels

    Science.gov (United States)

    Equihua-Guillén, F.; García-Lara, A. M.; Muñíz-Valdes, C. R.; Ortíz-Cuellar, J. C.; Camporredondo-Saucedo, J. E.

    2014-01-01

    This work presents relevant metallurgical considerations to produce galvanized dual phase steels from low cost aluminum-silicon steels which are produced by continuous strip processing. Two steels with different contents of Si and Al were austenized in the two-phase field ferrite + austenite (α + γ) in a fast manner to obtain dual phase steels, suitable for hot-dip galvanizing process, under typical parameters of continuous annealing processing line. Tensile dual phase properties were obtained from specimens cooled from temperature below Ar3, held during 3 min, intermediate cooling at temperature above Ar1 and quenching in Zn bath at 465 °C. The results have shown typical microstructure and tensile properties of galvanized dual phase steels. Finally, the synergistic effect of aluminum, silicon, and residual chromium on martensite start temperature ( M s), critical cooling rate ( C R), volume fraction of martensite, and tensile properties has been studied.

  1. On rolling of alloyed steels on the continuous light-section mill 250

    International Nuclear Information System (INIS)

    Grigor'ev, V.K.; Antipov, V.F.; Zamotin, V.M.; Kuznetsov, Yu.M.

    1976-01-01

    Using the method of computed ratios, the expected loads (torques) have been calculated in the rolling of alloyed steels on the light-section mill 250 of the Chelyabinsk metallurgical works. The deviation of the computed torques from those measured for steels 35GS and St5ps does not exceed -6%. Data are given on changes in torques during the rolling of alloyed steels in the different stands as compared with the actual data for the rolling of ordinary steel. Calculations show, and experimental data confirm, that, according to the torque value, it is possible to roll alloyed steels of sufficiently wide assortment on mill 250

  2. THE INFLUENCE OF POSTHEAT TREATMENT ON FERRITE REDISTRIBUTION IN DUPLEX STEELS ELECTRON BEAM WELDS

    Directory of Open Access Journals (Sweden)

    Zita Iždinská

    2009-04-01

    Full Text Available The duplex stainless steel is two-phase steel with the structure composed of austenite and ferrite with optimum austenite/ferrite proportion 50%. At present, classical arc processes for welding duplex steels are generally regarded as acceptable. On the other hand electron and laser beam welding is up to now considered less suitable for welding duplex steels. The submitted work presents the results of testing various thermal conditions at welding duplex stainless steel with electron beam. It was shown, that application of suitable postheat made possible to reduce the ferrite content in weld metal.

  3. Behaviour of Z phase in 9–12%Cr steels

    DEFF Research Database (Denmark)

    Danielsen, Hilmar Kjartansson; Hald, John

    2006-01-01

    The literature on the behaviour of modified Z phase Cr(V,Nb)N in creep resistant martensitic 9–12%Cr steels is briefly reviewed. Ten different 9–12%Cr steels were investigated after prolonged exposure at 600–660uC; the modified Z phase was found in all of them. In steels with high Cr content (11......–12%), Z phase precipitates much faster than in 9%Cr steels. Precipitation of Z phase is associated with dissolution of MX carbonitrides, and causes a breakdown in long term creep strength in 9–12%Cr steels. High Cr steels show creep instabilities accompanied with Z phase precipitation, whereas low Cr...... steels show good long term creep stability. A niobium free CrVN variant of the modified Z phase was observed for the first time during the course of this work. The solution temperature of the Cr(V,Nb)N and CrVN modified Z phases was found to be close to 800uC for 11–12%Cr steels, much lower than the 1200...

  4. Method of making steel strapping and strip

    Energy Technology Data Exchange (ETDEWEB)

    Robert D. Reilly

    2000-02-16

    The technical progress obtained for this time frame consisted of the awarding of two contracts for determination of metallurgical parameters for heat treatment of strapping and strip which are unavailable from current technology and/or published data in this field. The two contractors were Bricmont, Inc. and the Department of Materials Science and Engineering at the Technological Institute of Northwestern University, Evanston, IL. Phase 1 of the two stage contract with Bricmont, Inc. which provided a computer analysis of the cooling rates of a typical range of thickness' of strapping was completed. This study was developed for the purpose of determining the time parameters for quenching low carbon steels to a martensitic microstructure within the time frame of the design of the proposed process. It also provides design criteria for cooling to ambient for the total process. This data is required for Phase 2 of the Bricmont proposal which completes the design and specifications of the total heat treating and cooling system for the process. This becomes the basis for developing the cost and space requirements for this component of the production line. The authors do not intend to award Phase 2 until the work done at Northwestern University discussed hereafter is completed. On or about May 1, 1999 a contract for a project entitled ``Effects of Steel Composition and Quench Rate on Microstructure and Mechanical Properties of Strapping'' to be performed at the Department of Materials Science and Engineering was awarded. The delay in initiating this project was due to the legal interpretation and final agreement of the intellectual provisions of the award by the author's attorneys, Northwestern's attorneys and the legal representative in the Chicago office of the DOE. The work to date includes rapid quenching of a number of different steel compositions and microstructure on an existing drop quench test apparatus. It was initially assumed that this

  5. Thermochemical surface engineering of steels

    DEFF Research Database (Denmark)

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

  6. Study on mechanism of intergranular stress corrosion cracking and analysis of residual stress and work hardening in welds of low-carbon austenitic stainless steel with hard surface machining

    International Nuclear Information System (INIS)

    Mori, Hiroaki; Mochizuki, Masahito; Nishimoto, Kazutoshi; Toyoda, Masao; Katsuyama, Jinya

    2007-01-01

    In order to make clear the effects of residual stress and hardening on intergranular stress corrosion cracking (IGSCC) behavior in the welds of Type 316L low-carbon austenitic stainless steel with surface hardening, the residual stress and hardness in the butt-joint of pipes as a typical example of the actual structure were estimated and the grain boundary sliding was analyzed from the viewpoint of micro-deformation. On the basis of these results, the mechanism of IGSCC was discussed by the integrated knowledge between metallurgy and mechanics. The relationship between plastic strain and hardness in hard-machined surface near welds was clarified from the experimented relationship and the analysis method by the thermal elastic-plastic analysis. The distributions of hardness and residual stress with the actual surface machining could be simulated. It was made clear that grain boundary sliding occurred in the steel at 561K by a constant strain rate tensile test. From the comparison of grain boundary sliding behavior between solution treated specimen and cold-rolled one, it was found that the grain boundary sliding in cold-rolled one occurs in smaller strain conditions than that in as received one, and the amount of grain boundary sliding in cold-rolled one increases remarkably with increases in rolling reduction. In addition, it was clarified that the grain boundary energy is raised by the grain boundary sliding. On the basis of these results, it was concluded that the cause of IGSCC in the welds of Type 316L low-carbon austenitic stainless steel with surface hardening is the increase in grain boundary energy due to grain boundary sliding induced by residual stress of multi pass welding and surface hardening. (author)

  7. Behavior of Equipment Support Beam Joint Directly Connected to A Steel-plate Concrete(SC) Wall

    International Nuclear Information System (INIS)

    Kim, K. S.; Kwon, K. J.

    2008-01-01

    To decrease the time for building nuclear power plants, a modular construction method, 'Steel-plate Concrete(SC)', has been investigated for over a decade. To construct a SC wall, a pair of steel plates are placed in parallel similar to a form-work in conventional reinforced concrete (RC) structures, and concrete is filled between the steel plates. Instead of removing the steel plates after the concrete has cured, the steel plates serve as components of the structural member. The exposed steel plate of SC structures serves as the base plate for the equipment support, and the headed studs welded to the steel plates are used as anchor bolts. Then, a support beam can be directly welded to the surface of the steel plate in any preferred position. In this study, we discuss the behavior and evaluation method of the equipment support joint directly connected to exposed steel plate of SC wall

  8. 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)

  9. National steel tries wheeling

    International Nuclear Information System (INIS)

    Dudak, J.R.

    1992-01-01

    In 1989, National Steel felt the need to take the next step to make its Detroit-based division, Great Lakes Steel, more competitive in the world flat-rolled steel market. In 1988, Great Lakes Steel started flowing natural gas through the first fully litigated bypass (Competitive Sourcing Option) of a local distribution company. In 1989, the second connection with the new supply route for gas transportation, Panhandle Eastern had started flowing and the LDC, Michigan Consolidated Gas Co. (MichCon) had pulled out their piping previously serving the plants. Since we had been able to structure a fully reliable supply route, storage and balancing program for gas in the face of such strong opposition by the LDC, the author felt it was time to attack the next singularly sourced major commodity, electricity. Electricity, at this major integrated steel plant, represented approximately 7% of plant cost yearly. Yet being monopolized, Great Lakes Division (GLD) could not multiple source this commodity like it does with its other 93% of costs, except for labor (25% of the 93%). Multiple sourcing is done to bring competitive pressure to suppliers and to diversify supplies and protect plant operation in the event of failure by one supplier. This paper describes National Steel's strategy to reduce the cost of power, at the minimum of capital costs, the most expedient way possible, that does not sacrifice any major long-term potential cost improvements. The results show that competitively priced power is available across the mid-west, at prices well below many state regulated electric utilities, for at least 5 to 15 years, but with major obstacles in obtaining transmission access

  10. Volatilization from PCA steel alloy

    Energy Technology Data Exchange (ETDEWEB)

    Hagrman, D.L.; Smolik, G.R.; McCarthy, K.A.; Petti, D.A.

    1996-08-01

    The mobilizations of key components from Primary Candidate Alloy (PCA) steel alloy have been measured with laboratory-scale experiments. The experiments indicate most of the mobilization from PCA steel is due to oxide formation and spalling but that the spalled particles are large enough to settle rapidly. Based on the experiments, models for the volatization of iron, manganese, and cobalt from PCA steel in steam and molybdenum from PCA steel in air have been derived.

  11. Fatigue damage of steel components

    DEFF Research Database (Denmark)

    Fæster, Søren; Zhang, Xiaodan; Huang, Xiaoxu

    2014-01-01

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

  12. Engineering of rolled constructional microalloyed steel products

    International Nuclear Information System (INIS)

    Adamczyk, J.

    2003-01-01

    Flexibility of the microalloyed steels on manufacturing of products with high mechanical and technological properties at not exaggerated production costs, it caused of their application for different constructions and machines in many branches of economy. It is a reason of the big interest of this steel group and the improvement of metallurgical and technological processing. In the work the examples of applications of C-Mn microalloyed steels with V and N microadditions for production of long shape products of R p0.2 > 650 MPa and KCU2 > 57 Jcm -2 are presented. They are manufactured in the controlled rolling process. Moreover this work presents liquid metal treatment in ladlemann process and influence of ingots solidification conditions, controlled rolling of weldable plates with Nb, Ti, V and B microadditions which after quenching and tempering have R p0.2 > 870 MPa, KV -50 o C > 27 J and plastic strain ratio equals 1.2. This work also presents the energy saving rolling technology with controlled recrystallization (method of thermomechanical treatment) of improved Weldox 960 steel plates with Mb, Ti, V and B microadditions which have after high-temperature tempering R p0.2 > 100 MPa, KV -50 o C >90 J and plastic strain ratio is less than 1.2. The introduction of microalloyed constructional steels and the appropriate technology in the domestic industry will contribute to high-processed products with properties competitive to products manufactured in high-industrialized countries. Thanks to that it will be possible to increase the technical level as well as to reduce production costs and import. (author)

  13. Thermally Stable Nanocrystalline Steel

    Science.gov (United States)

    Hulme-Smith, Christopher Neil; Ooi, Shgh Woei; Bhadeshia, Harshad K. D. H.

    2017-10-01

    Two novel nanocrystalline steels were designed to withstand elevated temperatures without catastrophic microstructural changes. In the most successful alloy, a large quantity of nickel was added to stabilize austenite and allow a reduction in the carbon content. A 50 kg cast of the novel alloy was produced and used to verify the formation of nanocrystalline bainite. Synchrotron X-ray diffractometry using in situ heating showed that austenite was able to survive more than 1 hour at 773 K (500 °C) and subsequent cooling to ambient temperature. This is the first reported nanocrystalline steel with high-temperature capability.

  14. Joining uranium to steel

    International Nuclear Information System (INIS)

    Perkins, M.A.

    1976-05-01

    A method has been devised which will allow the joining of uranium to steel by fusion welding through the use of an intermediate material. Uranium-0.5 titanium was joined to AISI 304L stainless steel by using a vanadium insert. Also, a method is now available for selecting possible filler metals when two entirely dissimilar metals need to be joined. This method allows a quantitative ranking to be made of the possible filler metals and thus the most likely candidate can be selected

  15. Effect of Aluminum Alloying on the Hot Deformation Behavior of Nano-bainite Bearing Steel

    Science.gov (United States)

    Yang, Z. N.; Dai, L. Q.; Chu, C. H.; Zhang, F. C.; Wang, L. W.; Xiao, A. P.

    2017-12-01

    Interest in using aluminum in nano-bainite steel, especially for high-carbon bearing steel, is gradually growing. In this study, GCr15SiMo and GCr15SiMoAl steels are introduced to investigate the effect of Al alloying on the hot deformation behavior of bearing steel. Results show that the addition of Al not only notably increases the flow stress of steel due to the strong strengthening effect of Al on austenite phase, but also accelerates the strain-softening rates for its increasing effect on stacking fault energy. Al alloying also increases the activation energy of deformation. Two constitutive equations with an accuracy of higher than 0.99 are proposed. The constructed processing maps show the expanded instability regions for GCr15SiMoAl steel as compared with GCr15SiMo steel. This finding is consistent with the occurrence of cracking on the GCr15SiMoAl specimens, revealing that Al alloying reduces the high-temperature plasticity of the bearing steel. On the contrary, GCr15SiMoAl steel possesses smaller grain size than GCr15SiMo steel, manifesting the positive effect of Al on bearing steel. Attention should be focused on the hot working process of bearing steel with Al.

  16. Sliding Wear Characteristics and Corrosion Behaviour of Selective Laser Melted 316L Stainless Steel

    Science.gov (United States)

    Sun, Y.; Moroz, A.; Alrbaey, K.

    2014-02-01

    Stainless steel is one of the most popular materials used for selective laser melting (SLM) processing to produce nearly fully dense components from 3D CAD models. The tribological and corrosion properties of stainless steel components are important in many engineering applications. In this work, the wear behaviour of SLM 316L stainless steel was investigated under dry sliding conditions, and the corrosion properties were measured electrochemically in a chloride containing solution. The results show that as compared to the standard bulk 316L steel, the SLM 316L steel exhibits deteriorated dry sliding wear resistance. The wear rate of SLM steel is dependent on the vol.% porosity in the steel and by obtaining full density it is possible achieve wear resistance similar to that of the standard bulk 316L steel. In the tested chloride containing solution, the general corrosion behaviour of the SLM steel is similar to that of the standard bulk 316L steel, but the SLM steel suffers from a reduced breakdown potential and is more susceptible to pitting corrosion. Efforts have been made to correlate the obtained results with porosity in the SLM steel.

  17. Porous stainless steel for biomedical applications

    Directory of Open Access Journals (Sweden)

    Sabrina de Fátima Ferreira Mariotto

    2011-01-01

    Full Text Available Porous 316L austenitic stainless steel was synthesized by powder metallurgy with relative density of 0.50 and 0.30 using 15 and 30 wt. (% respectively of ammonium carbonate and ammonium bicarbonate as foaming agents. The powders were mixed in a planetary ball mill at 60 rpm for 10 minutes. The samples were uniaxially pressed at 287 MPa and subsequently vacuum heat treated in two stages, the first one at 200 ºC for 5 hours to decompose the carbonate and the second one at 1150 ºC for 2 hours to sinter the steel. The sintered samples had a close porous structure and a multimodal pore size distribution that varied with the foaming agent and its concentration. The samples obtained by addition of 30 wt. (% of foaming agents had a more homogeneous porous structure than that obtained with 15 wt. (%. The MTT cytotoxicity test (3-[4,5-dimethylthiazol]-2,5-diphenyltetrazolium bromide was used to evaluate the mitochondrial activity of L929 cells with samples for periods of 24, 48, and 72 hours. The cytotoxicity test showed that the steel foams were not toxic to fibroblast culture. The sample with the best cellular growth, therefore the most suitable for biomedical applications among those studied in this work, was produced with 30 wt. (% ammonium carbonate. In this sample, cell development was observed after 48 hours of incubation, and there was adhesion and spreading on the material after 72 hours. Electrochemical experiments using a chloride-containing medium were performed on steel foams and compared to massive steel. The massive steel had a better corrosion performance than the foams as the porosity contributes to increase the surface area exposed to the corrosive medium.

  18. DEVELOPMENT OF THE DOPING MATRIX FOR CREATION OF THE BELORUSSIAN INSTRUMENTAL STEELS ON THE BASIS OF STEEL 70K(Y7A PRODUCED BY RUP “BMZ” (view and investigation

    Directory of Open Access Journals (Sweden)

    D. M. Kukuj

    2004-01-01

    Full Text Available Theoretical and practical aspects of production of the Belorussian instrumental steels on the base of the steel of type 70K are considered. The ways of working out of the alloy complex for receiving of the die steels in the conditions of RUP “BMZ” are shown.

  19. Silicate enamel for alloyed steel

    International Nuclear Information System (INIS)

    Ket'ko, K.K.

    1976-01-01

    The use of silicate enamels in the metallurgical industry is discussed. Presented are the composition and the physico-chemical properties of the silicate enamel developed at the factory 'Krasnyj Oktyabr'. This enamel can be used in the working conditions both in the liquid and the solid state. In so doing the enamel is melted at 1250 to 1300 deg C, granulated and then reduced to a fraction of 0.3 to 0.5 mm. The greatest homogeneity is afforded by a granulated enamel. The trials have shown that the conversion of the test ingots melted under a layer of enamel leads to the smaller number of the ingots rejected for surface defect reasons and the lower metal consumption for slab cleaning. The cost of the silicate enamel is somewhat higher than that of synthetic slags but its application to the melting of stainless steels is still economically beneficial and technologically reasonable. Preliminary calculations only for steel EhI4IEh have revealed that the use of this enamel saves annually over 360000 roubles [ru

  20. Steel Bar corrosion monitoring based on encapsulated piezoelectric sensors

    Science.gov (United States)

    Xu, Ying; Tang, Tianyou

    2018-05-01

    The durability of reinforced concrete has a great impact on the structural bearing capacity, while the corrosion of steel bars is the main reason for the degradation of structural durability. In this paper, a new type of encapsulated cement based piezoelectric sensor is developed and its working performance is verified. The consistency of the finite element simulation and the experimental results shows the feasibility of monitoring the corrosion of steel bars using encapsulated piezoelectric sensors. The research results show that the corrosion conditions of the steel bars can be determined by the relative amplitude of the measured signal through the encapsulated piezoelectric sensor.

  1. Structural inheritance in cast 30KhGNM-type steel

    International Nuclear Information System (INIS)

    Sadovskij, V.D.; Bershtejn, L.I.; Mel'nikova, A.A.; Polyakova, A.M.; Schastlivtsev, V.M.

    1980-01-01

    Structural inheritance in the cast 30KhGNM-type steel depending on the heating rate and the temperature of preliminary tempering is investigated. When eating the cast steel with a beinite structure at the rate of 1-150 deg/min, the restoration of austenite grain and the following recrystallization due to the phase cold work, are observed. Slow heating from room temperature or preliminary tempering hinder grain restoration during heating. A non-monotonous effect of tempering temperature on the structural inheritance is established which can be connected with the kinetics of decomposition of residual austenite in steel

  2. Photometric and emission-spectrometric determination of boron in steels

    International Nuclear Information System (INIS)

    Thierig, D.

    1982-01-01

    A method for the photometric determination of boron in unalloyed and alloyed steels is described, in which Curcumine is used as reagent. A separation of boron is not necessary. Limit of detection: 0.0003% B. The decomposition of boron nitride in the steel is achieved by heating the whole sample in fuming sulphuric acid/phosphoric acid. For the emission spectrometric investigation of solid steel samples and for the spectrochemical analysis of solutions with plasma excitation working parameters are given and possibilities of interferences are demonstrated. (orig.) [de

  3. Predicting the Abrasion Resistance of Tool Steels by Means of Neurofuzzy Model

    Directory of Open Access Journals (Sweden)

    Dragutin Lisjak

    2013-07-01

    Full Text Available This work considers use neurofuzzy set theory for estimate abrasion wear resistance of steels based on chemical composition, heat treatment (austenitising temperature, quenchant and tempering temperature, hardness after hardening and different tempering temperature and volume loss of materials according to ASTM G 65-94. Testing of volume loss for the following group of materials as fuzzy data set was taken: carbon tool steels, cold work tool steels, hot work tools steels, high-speed steels. Modelled adaptive neuro fuzzy inference system (ANFIS is compared to statistical model of multivariable non-linear regression (MNLR. From the results it could be concluded that it is possible well estimate abrasion wear resistance for steel whose volume loss is unknown and thus eliminate unnecessary testing.

  4. Guns, Germs and Steel

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 1. Guns, Germs and Steel - A Short History of Everybody for the Last 13,000 years. Suri Venkatachalam. Book Review Volume 6 Issue 1 January 2001 pp 84-88. Fulltext. Click here to view fulltext PDF. Permanent link:

  5. Underwater welding of steel

    International Nuclear Information System (INIS)

    Ibarra, S.; Olson, D.L.

    1992-01-01

    A fundamental basis to understand the behavior of wet underwater welding of steel is introduced. Both the pyrometallurgical and physical metallurgy concepts are discussed. Modifications of welding consumables and practice are suggested. This chapter promotes further contributions of meatllurgical research to improve and promote wet underwater welding. (orig.)

  6. Japan steel mill perspective

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-07-01

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

  7. Low temperature plasma carburizing of AISI 316L austenitic stainless steel and AISI F51 duplex stainless steel

    OpenAIRE

    Pinedo,Carlos Eduardo; Tschiptschin,André Paulo

    2013-01-01

    In this work an austenitic AISI 316L and a duplex AISI F51 (EN 1.4462) stainless steel were DC-Plasma carburized at 480ºC, using CH4 as carbon carrier gas. For the austenitic AISI 316L stainless steel, low temperature plasma carburizing induced a strong carbon supersaturation in the austenitic lattice and the formation of carbon expanded austenite (γC) without any precipitation of carbides. The hardness of the carburized AISI 316L steel reached a maximum of 1000 HV due to ∼13 at% c...

  8. Low temperature plasma carburizing of AISI 316L austenitic stainless steel and AISI F51 duplex stainless steel

    OpenAIRE

    Pinedo, Carlos Eduardo; Tschiptschin, André Paulo

    2013-01-01

    In this work an austenitic AISI 316L and a duplex AISI F51 (EN 1.4462) stainless steel were DC-Plasma carburized at 480ºC, using CH4 as carbon carrier gas. For the austenitic AISI 316L stainless steel, low temperature plasma carburizing induced a strong carbon supersaturation in the austenitic lattice and the formation of carbon expanded austenite (γC) without any precipitation of carbides. The hardness of the carburized AISI 316L steel reached a maximum of 1000 HV due to ∼13 at% carbon super...

  9. Chromium Enrichment on P11 Ferritic Steel by Pack Cementation

    OpenAIRE

    Fauzi F. A.; Kurniawan T.; Salwani M. S.; Bin Y. S.; Harun W. S. W.

    2016-01-01

    The future thermal power plant is expected to operate at higher temperature to improve its efficiency and to reduce greenhouse gas emission. This target requires better corrosion properties of ferritic steels, which commonly used as materials for superheater and reheater of boiler tubes. In this work, chromium enrichment on the surface of ferritic steel is studied. The deposited chromium is expected to become a reservoir for the formation of chromia protective layer. Chromium was deposited on...

  10. Corrosion under stress of AISI 304 steel in thiocyanate solutions

    International Nuclear Information System (INIS)

    Perillo, P.M.; Duffo, G.S.

    1989-01-01

    Corrosion susceptibility under stress of AISI 304 steel sensitized in a sodium thiocyanate solution has been studied and results were compared with those obtained with solutions of thiosulfate and tetrathionate. Sensitized steel type 304 is highly susceptible to corrosion when under intergranular stress (IGSCC) in thiocyanate solutions but the aggressiveness of this anion is less than that of the other sulphur anions studied (thiosulfate and tetrathionate). This work has been partly carried out in the Chemistry Department. (Author) [es

  11. Improvement of the steel quality through zirconia base ceramic filter

    International Nuclear Information System (INIS)

    Santos, Benedito M.; Foschini, Cesar R.; Santos, Ieda M.G.; Pinheiro, Adriano S.; Paskocimas, Carlos A.; Leite, Edson R.; Longo, Elson

    1997-01-01

    At the end of production, the steel presents inclusions own to the making process. Ceramics filters, with controlled porosity, are being produced to eliminate the impurities, so as to increase the good quality steel production. This work studies the optimization of the zirconia filters composition and production for siderurgical processes application. The study was done through the granulometric control, using BET, XRD and Hg Porosimetry. (author)

  12. On electrical resistivity of AISI D2 steel during various stages of cryogenic treatment

    Science.gov (United States)

    Lomte, Sachin Vijay; Gogte, Chandrashekhar Laxman; Peshwe, Dilip

    2012-06-01

    The effect of dislocation densities and residual stresses is well known in tool steels. Measurement of electrical resistivity in order to monitor dislocation densities or residual stresses has seldom been used in investigating the effect of cryogenic treatment on tool steels. Monitoring residual stresses during cryogenic treatment becomes important as it is directly related to changes due to cryogenic treatment of tool steels. For high carbon high chromium (HCHC- AISI D2) steels, not only wear resistance but dimensional stability is an important issue as the steels are extensively used in dies, precision measuring instruments. This work comprises of study of measurement of electrical resistivity of AISI D2 steel at various stages of cryogenic treatment. Use of these measurements in order to assess the dimensional stability of these steels is discussed in this paper.

  13. Forming of High-strength Steels Using a Hot-melt Dry Lubricant

    DEFF Research Database (Denmark)

    Hörnström, Sven-Erik; Karlsson, Erik; Olsson, Mikael

    2008-01-01

    during forming resulting in seizure of the tool/steel sheet contact and extensive scratching of the steel sheet surface. As a result, a number of concepts have been developed in order to reduce the tendency to galling in metal forming, including the development of new dry lubricants, new forming tool...... steel grades and improved surface engineering treatments such as the deposition of low friction CVD and PVD coatings. In the present study the performance of a hot-melt dry lubricant in the forming of hot and cold rolled and hot-dip galvanized high strength steel has been evaluated and compared...... with a conventional rust protection oil using four different tests methods, i.e. a strip reduction test, a bending under tension test, a stretch-forming test and a pin-on disc test. In the tests, two different cold work tool steels, a conventional steel grade and a nitrogen alloyed PM steel grade were evaluated...

  14. Challenges in Special Steel Making

    Science.gov (United States)

    Balachandran, G.

    2018-02-01

    Special bar quality [SBQ] is a long steel product where an assured quality is delivered by the steel mill to its customer. The bars have enhanced tolerance to higher stress application and it is demanded for specialised component making. The SBQ bars are sought for component making processing units such as closed die hot forging, hot extrusion, cold forging, machining, heat treatment, welding operations. The final component quality of the secondary processing units depends on the quality maintained at the steel maker end along with quality maintained at the fabricator end. Thus, quality control is ensured at every unit process stages. The various market segments catered to by SBQ steel segment is ever growing and is reviewed. Steel mills need adequate infrastructure and technological capability to make these higher quality steels. Some of the critical stages of processing SBQ and the critical quality maintenance parameters at the steel mill in the manufacture has been brought out.

  15. Accelerated corrosion of stainless steel in thiocyanate-containing solutions

    Energy Technology Data Exchange (ETDEWEB)

    Pistorius, P Chris; Li, Wen

    2012-09-19

    It is known that reduced sulfur compounds (such as thiocyanate and thiosulfate) can accelerate active corrosion of austenitic stainless steel in acid solutions, but before we started this project the mechanism of acceleration was largely unclear. This work combined electrochemical measurements and analysis using scanning electron microscopy (SEM) and X-ray photo-electron spectroscopy (XPS), which provided a comprehensive understanding of the catalytic effect of reduced sulfur species on the active corrosion of stainless steel. Both the behavior of the pure elements and the steel were studied and the work focused on the interaction between the pure elements of the steel, which is the least understood area. Upon completion of this work, several aspects are now much clearer. The main results from this work can be summarized as follows: The presence of low concentrations (around 0.1 mM) of thiocyanate or tetrathionate in dilute sulfuric acid greatly accelerates the anodic dissolution of chromium and nickel, but has an even stronger effect on stainless steels (iron-chromium-nickel alloys). Electrochemical measurements and surface analyses are in agreement with the suggestion that accelerated dissolution really results from suppressed passivation. Even well below the passivation potential, the electrochemical signature of passivation is evident in the electrode impedance; the electrode impedance shows clearly that this pre-passivation is suppressed in the presence of thiocyanate. For the stainless steels, remarkable changes in the morphology of the corroded metal surface and in the surface concentration of chromium support the suggestion that pre-passivation of stainless steels is suppressed because dissolution of chromium is accelerated. Surface analysis confirmed that adsorbed sulfur / sulfide forms on the metal surfaces upon exposure to solutions containing thiocyanate or thiosulfate. For pure nickel, and steels containing nickel (and residual copper), bulk sulfide

  16. Heat Treatment and Properties of Iron and Steel

    National Research Council Canada - National Science Library

    Digges, Thomas

    1966-01-01

    .... Chemical compositions, heat treatments, and some properties and uses are presented for structural steels, tool steels, stainless and heat-resisting steels, precipitation-hardenable stainless steels...

  17. Weld bonding of stainless steel

    DEFF Research Database (Denmark)

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

    2004-01-01

    . The overall assessment of the weld bonding process is made using several commercial adhesives with varying working times under different surface conditions. The quality of the resulting joints is evaluated by means of macroetching observations, tension-shear tests and peel tests. The theoretical investigation......This paper presents a comprehensive theoretical and experimental investigation of the weld bonding process with the purpose of evaluating its relative performance in case of joining stainless steel parts, against alternative solutions based on structural adhesives or conventional spot-welding...... of the process consists of numerical predictions based on the commercial finite element program SORPAS with the purpose of establishing the most favourable parameters that allow spot-welding through the adhesives....

  18. Additive manufacturing for steels: a review

    Science.gov (United States)

    Zadi-Maad, A.; Rohib, R.; Irawan, A.

    2018-01-01

    Additive manufacturing (AM) of steels involves the layer by layer consolidation of powder or wire feedstock using a heating beam to form near net shape products. For the past decades, the AM technique reaches the maturation of both research grade and commercial production due to significant research work from academic, government and industrial research organization worldwide. AM process has been implemented to replace the conventional process of steel fabrication due to its potentially lower cost and flexibility manufacturing. This paper provides a review of previous research related to the AM methods followed by current challenges issues. The relationship between microstructure, mechanical properties, and process parameters will be discussed. Future trends and recommendation for further works are also provided.

  19. Experiences within British Steel since 1989

    International Nuclear Information System (INIS)

    Harvey, D.S.

    1999-01-01

    The experience of British steel is that there is a serious and continuing threat of radioactive material being included in scrap delivered to steelworks. All scrap entering the steelworks is monitored for radioactivity. The scrap suppliers and the national authorities have recognized the difficulties caused by the presence of radioactivity in scrap, and are working to minimise the problem. Both domestic and imported scrap has been found to contain radioactivity, but the imported scrap is much more likely to contain radioactivity. If radioactivity is found the Environmental Agency is informed, and established procedures are used to minimise the hazard, and to isolate the radioactivity. Detecting, and isolating radioactive scrap, and preventing it being re-melted in the steelmaking process, is part of the overall commitment of British Steel to work safely, and to provide a safe, good quality, product (author)

  20. Stainless steel electrochemical behaviour - application to the decontamination of steel parts contaminated by tritium

    International Nuclear Information System (INIS)

    Bellanger, G.

    1991-01-01

    This purpose of this work is the study of an electrochemical decontamination process of stainless steel in which tritium is present on the surface of the metal, in the oxide layer and in the metal. We have first investigated the behaviour of the oxide layer. Then we have studied the hydrogen evolution, its diffusion and retrodiffusion in the metal. The results are applied to the decontamination of steel parts contamined by tritium. Part of the tritium can be eliminated by reducing the oxyde layer, which contains large amounts of tritium. However, it is more beneficial to electrolyse at the potential at which the H + ions are reduced. The hydrogen on the steel surface enters in the metal and displaces most of tritium located in the metallic layers near the surface. The tritium surface elimination rate is about 95%. The tritium eliminated through electrolysis is only a small fraction of all the tritium contained in the metal. However, according to conservation experiments of parts after electrolysis, it can be concluded that hydrogen, probably more strongly bound than tritium to steel, forms near the surface a barrier that prevents tritium retrodiffusion. Electrolysis appears as a satisfactory process for the surface decontamination of slightly tritiated steel parts. A decontamination automaton based on the preceding results is described using a pad electrolyser. This type of decontamination is little polluting, and the parts can be recycled after the in situ treatment [fr

  1. Vale do Aco pipeline: pipeline natural gas implementation in ArcelorMittal Monlevade steel work; Gasoduto Vale do Aco: implantacao do gas natural via gasoduto na ArcelorMittal Monlevade

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Eduardo Sergio da Silva; Arantes, Luiz Flavio Mourao; Ribeiro, Vicente Aleixo Pinheiro [ArcelorMittal Monlevade, Joao Monlevade, MG (Brazil)

    2011-12-21

    Since September 2010, ArcelorMittal Monlevade has gained flexibility and an important opportunity to reduce the cost of its energy mix due to the arrival of the Natural Gas (NG) via Steel Valley Pipeline. The proposal of the project included the substitution of the Liquefied Petroleum Gas (LPG), Fuel Oil and Compressed Natural Gas for natural gas via pipeline. To support the investment decision, in addition to domestic economic and technical aspects, the macro economic environment concerning the NG was also taken into account. This paper shows the analysis for adjustment of internal equipment, the structure of the contract, the conceptual project of the gas distribution built inside the main events, the gains achieved, the alternatives for the acquisition of NG and operational flexibility of ArcelorMittal Monlevade in case of interruption of supply of natural gas. (author)

  2. Influence of carbide precipitation upon hydrogen fragilization of an AISI 304 steel

    International Nuclear Information System (INIS)

    Hazarabedian, A.E.; Ovejero Garcia, J.

    1991-01-01

    The present work deals with austenitic stainless steels for a family of steels that is renowned for its high resistance to hydrogen fragilization. Nevertheless, these steels may suffer hydrogen fragilization under severe working conditions. This fact is strongly dependent on many factors -composition, grain size, other phases present, corrosion sensitivity, etc.-. While there are studies that show how intergranular corrosion is influenced by corrosion sensitivity -mainly due to carbide precipitation in grain boundaries-, there are no reports about the effect of the carbide precipitation itself on hydrogen fragilization for these steels. (Author) [es

  3. Gaseous surface hardening of martensitic stainless steels

    DEFF Research Database (Denmark)

    Tibollo, Chiara; Villa, Matteo; Christiansen, Thomas L.

    The present work addresses heat and surface treatments of martensitic stainless steel EN 1.4028. Different combinations of heat treatments and surface treatments were performed: conventional austenitisation, cryogenic treatment and in particular high temperature solution nitriding (HTSN) and low...... that cubic lath martensite in conventionally austenitised EN 1.4028 dissolves nitrogen and develops expanded martensite (ferrite) during LTSH. HTSN leads to a microstructure of tetragonal plate martensite and retained austenite. The content of retained austenite can be reduced by a cryo...

  4. COMPLEX SURFACE HARDENING OF STEEL ARTICLES

    Directory of Open Access Journals (Sweden)

    A. V. Kovalchuk

    2014-01-01

    Full Text Available The method of complex surface hardening of steel detailswas designed. The method is a compound of two processes of hardening: chemical heat treatment and physical vapor deposition (PVD of the coating. The result, achieved in this study is much higher, than in other work on this topic and is cumulative. The method designed can be used in mechanical engineering, medicine, energetics and is perspective for military and space technologies.

  5. Current status of iron and steelmaking technology at Tata Steel

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, B.D.; Poddar, M.N.; Chandra, S. [Tata Steel, Jamshedpur (India)

    2002-07-01

    Tata Steel was set up in the early years of the 20th century and over the years the plant has grown into one of the most modern steel plants in the world. The philosophy of phase-wise modernisation on a continuing basis was adopted by Tata Steel with great advantage for the modernisation of the two million tonne Jamshedpur Steel Works. Four phases of the modernisation programme have already been successfully completed and their gains consolidated. Adoption and absorption of the latest technologies, fundamental changes in the operating philosophy and setting of stretch performance targets have brought about this remarkable transformation. The recently commissioned state of the art 1.2 Mtpa Cold Rolling Mill Complex is an example of Tata Steel remaining in harmony with times. Another is the use of pulverised coal injection in blast furnaces. The paper highlights some of the important technological developments in integrated steel plants, particularly those being practiced at Tata Steel, in the areas of ironmaking, steelmaking, casting and rolling for retaining its competitive position in the global market with regard to cost, customer and change. 9 refs., 21 figs., 2 tabs.

  6. Evaluation of workability and strength of green concrete using waste steel scrap

    Science.gov (United States)

    Neeraja, D.; Arshad, Shaik Mohammed; Nawaz Nadaf, Alisha K.; Reddy, Mani Kumar

    2017-11-01

    This project works on the study of workability and mechanical properties of concrete using waste steel scrap from the lathe industry. Lathe industries produce waste steel scrap from the lathe machines. In this study, an attempt is made to use this waste in concrete, as accumulation of waste steel scrap cause disposal problem. Tests like compressive test, split tensile test, NDT test (UPV test) were conducted to determine the impact of steel scrap in concrete. The percentages of steel scrap considered in the study were 0%, 0.5%, 1%, 1.5%, and 2% respectively by volume of concrete, 7 day, 28 days test were conducted to find out strength of steel scrap concrete. It is observed that split tensile strength of steel scrap concrete is increased slightly. Split tensile strength of Steel scrap concrete is found to be maximum with volume fraction of 2.0% steel scrap. The steel scrap gives good result in split tensile strength of concrete. From the study concluded that steel scrap can be used in concrete to reduce brittleness of concrete to some extent.

  7. The effect of intermediate stop and ball size in fabrication of recycled steel powder using ball milling from machining steel chips

    International Nuclear Information System (INIS)

    Fitri, M.W.M.; Shun, C.H.; Rizam, S.S.; Shamsul, J.B.

    2007-01-01

    A feasibility study for producing recycled steel powder from steel scrap by ball milling was carried out. Steel scrap from machining was used as a raw material and was milled using planetary ball milling. Three samples were prepared in order to study the effect of intermediate stop and ball size. Sample with intermediate stop during milling process showed finer particle size compared to the sample with continuous milling. Decrease in the temperature of the vial during the intermediate stop milling gives less ductile behaviour to the steel powder, which is then easily work-hardened and fragmented to fine powder. Mixed small and big size ball give the best production of recycled steel powder where it gives higher impact force to the scrap and accelerate the fragmentation of the steel scrap into powder. (author)

  8. Welding of heterogeneous 12Kh2MFSR steels with the Mn-Cr-Si-Ni system

    International Nuclear Information System (INIS)

    Smirnov, A.N.; Belogolov, E.I.

    1978-01-01

    The process of welding pipes of the 12Kh2MFSR pearlitic steels and austenitic steels of the Mn-Cr-Si-Ni system was studied. The filler materials were selected, and the working capacity of welded joints was examined in ageing and cyclic heatings. The microhardness of steels was measured, and the ultimate strength of welded joints was determined. The following has been established: the composite joints of steels of the Mn-Cr-Si-Ni system and 12Kh2MFSR steel are advisable to be welded on a coating layer welded by the EhA395/9 electrodes on the surface of a pipe of the 12Kh2MFSR pearlitic steel; this guarantees the sufficient working capacity of welded joints

  9. Steel for nuclear applications

    International Nuclear Information System (INIS)

    Zorev, N.N.; Astafiev, A.A.; Loboda, A.S.

    1978-01-01

    A steel contains, in percent by weight, the following constituents: carbon from 0.13 to 0.18, silicon from 0.17 to 0.37, manganese from 0.30 to 0.60, chromium from 1.7 to 2.4, nickel from 1.0 to 1.5, molybdenum from 0.5 to 0.7, vanadium from 0.05 to 0.12, aluminium from 0.01 to 0.035, nitrogen from 0.05 to 0.012, copper from 0.11 to 0.20, arsenic from 0.0035 to 0.0055, iron and impurities, the balance. This steel is preferable for use in the manufacture of nuclear reactors. 1 table

  10. Advances in stainless steels

    International Nuclear Information System (INIS)

    Baldev Raj; Jayakumar, T.; Saibaba, Saroja; Sivaprasad, P.V.; Shankar, P.

    2010-01-01

    This book covers a broad spectrum of topics spanning the entire life cycle of stainless steel-from alloy design and characterization to engineering design, fabrication, mechanical properties, corrosion, quality assurance of components, in-service performance assessment, life prediction and finally failure analysis of materials and components. The contents provide useful feedback for further developments aimed at effective utilization of this class of materials. The book comprises articles that bring out contemporary developments in stainless steels and is thematically classified into the following sections. 1. Component design, modelling and structural integrity, 2. Manufacturing technology, 3. Property evaluation, 4. Alloy development and applications, 5. NDE methods, 6. Corrosion and surface modification. The book commences with articles on component design and structural integrity, thus opening up the areas of challenge for researchers and academia. The articles in the book relevant to INIS are indexed separately

  11. Steel containment buckling

    International Nuclear Information System (INIS)

    Butler, T.A.; Baker, W.E.

    1986-01-01

    Two aspects of buckling of a free-standing nuclear steel containment building were investigated in a combined experimental and analytical program. In the first part of the study, the response of a scale model of a containment building to dynamic base excitation is investigated. A simple harmonic signal was used for preliminary studies followed by experiments with scaled earthquake signals as the excitation source. The experiments and accompanying analyses indicate that the scale model response to earthquake-type excitations is very complex and that current analytical methods may require a dynamic capacity reduction factor to be incorporated. The second part of the study quantified the effects of framing at large penetrations on the static buckling capacity of scale model containments. Results show little effect from the framing for the scale models constructed from the polycarbonate, Lexan. However, additional studies with a model constructed of the prototypic steel material are suggested

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

    International Nuclear Information System (INIS)

    Nasser, A.

    2010-01-01

    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)

  13. Reactor pressure vessel steels

    International Nuclear Information System (INIS)

    Van De Velde, J.; Fabry, A.; Van Walle, E.; Chaouuadi, R.

    1998-01-01

    Research and development activities related to reactor pressure vessel steels during 1997 are reported. The objectives of activities of the Belgian Nuclear Research Centre SCK/CEN in this domain are: (1) to develop enhanced surveillance concepts by applying micromechanics and fracture-toughness tests to small specimens, and by performing damage modelling and microstructure characterization; (2) to demonstrate a methodology on a broad database; (3) to achieve regulatory acceptance and industrial use

  14. Reactor Pressure Vessel Steels

    Energy Technology Data Exchange (ETDEWEB)

    Van de Velde, J.; Fabry, A.; Van Walle, E.; Chaoudi, R

    1998-07-01

    SCK-CEN's R and D programme on Reactor Pressure Vessel (RPV) Steels in performed in support of the RVP integrity assessment. Its main objectives are: (1) to develop enhanced surveillance concepts by applying micromechanics and fracture-toughness tests to small specimens, and by performing damage modelling and microstructure characterization; (2) to demonstrate the applied methodology on a broad database; (3) to achieve regulatory acceptance and industrial use. Progress and achievements in 1999 are reported.

  15. Steele Richardson Olszewski syndrome

    Directory of Open Access Journals (Sweden)

    Vijayashree S Gokhale

    2013-01-01

    Full Text Available Parkinson′s disease and its plus syndromes are an important cause of morbidity in the geriatric age group. Its plus syndromes show a myriad of clinical features characterized by progressive symptoms. Here we present a 65-year-old woman with progressive "Parkinsonian-like features," i.e., mask-like face, slowness of all movements and tendency to fall, and difficulty in eye movements, leading to the diagnosis of Steele Richardson Olszewski Syndrome or progressive supranuclear palsy.

  16. Steels and welding nuclear

    International Nuclear Information System (INIS)

    Sessa, M.; Milella, P.P.

    1987-01-01

    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

  17. Contaminated Mexican steel incident

    International Nuclear Information System (INIS)

    1985-01-01

    This report documents the circumstances contributing to the inadvertent melting of cobalt 60 (Co-60) contaminated scrap metal in two Mexican steel foundries and the subsequent distribution of contaminated steel products into the United States. The report addresses mainly those actions taken by US Federal and state agencies to protect the US population from radiation risks associated with the incident. Mexico had much more serious radiation exposure and contamination problems to manage. The United States Government maintained a standing offer to provide technical and medical assistance to the Mexican Government. The report covers the tracing of the source to its origin, response actions to recover radioactive steel in the United States, and return of the contaminated materials to Mexico. The incident resulted in significant radiation exposures within Mexico, but no known significant exposure within the United States. Response to the incident required the combined efforts of the Nuclear Regulatory Commission (NRC), Department of Energy, Department of Transportation, Department of State, and US Customs Service (Department of Treasury) personnel at the Federal level and representatives of all 50 State Radiation Control Programs and, in some instances, local and county government personnel. The response also required a diplomatic interface with the Mexican Government and cooperation of numerous commercial establishments and members of the general public. The report describes the factual information associated with the event and may serve as information for subsequent recommendations and actions by the NRC. 8 figures

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

    Science.gov (United States)

    1975-04-01

    work of Kerns (36)] 29 22 Crack Velocity vs. Stress Intensity for AISI 4340 Steel (Martensitic and Bainitic Structures) in 314 NaCl Solution (pit = 6.0...magnitude greater for 4340 steel with a tempered martensite structure than for the lower bainite structure. Figure 22 shows crack velocity as a function of...applied stress intensity for martensitic and bainitic steels . The dif- ference was attributed to more effective trapping of hydrogen at coher- ently

  19. Microstructure and Mechanical Behavior of Deep Drawing DC04 Steel at Different Length Scales

    OpenAIRE

    Schreijäg, Simone

    2013-01-01

    The deformation behavior of steels is strongly influenced by their microstructure which is a result of the alloying elements and thermal treatments. In this work, the microstructure and the deformation behavior of a non-alloyed deep drawing DC04 steel was investigated. The microstructure was analyzed during heat treatment by EBSD, then microcompression experiments were performed on selected microstructural units and then bulk steel samples were mechanically tested by tensile experiments.

  20. The effects of fast-neutron irradiation on the mechanical properties of austenitic stainless steel

    International Nuclear Information System (INIS)

    Dalton, J.H.

    1978-01-01

    The paper reviews the effects of fast-neutron irradiation on the tensile properties of austenitic stainless steels at irradiation temperatures of less than 400 degrees Celcius, using as an example, work carried out at Pelindaba on an AISI 316 type steel produced in South Africa. Damage produced in these steels at higher irradiation temperatures and fluences is also briefly discussed. The paper concludes with a discussion of some methods of overcoming or decreasing the effects of irradiation damage [af

  1. Effect of Microstructure on the Wear Behavior of Heat Treated SS-304 Stainless Steel

    OpenAIRE

    S. Kumar

    2016-01-01

    Sliding wear characteristics of some heat treated SS-304 stainless steel against EN-8 steel in dry condition have been studied in the present experimental work. Samples of SS-304 stainless steel have been heated in a muffle furnace in desired temperature and allowed to dwell for two hours. The heated specimen are then cooled in different media namely inside the furnace, open air, cutting grade oil (grade 44) and water at room temperature to obtain different grades of heat treatment. Microstr...

  2. Friction Stir Welding of HT9 Ferritic-Martensitic Steel: An Assessment of Microstructure and Properties

    Science.gov (United States)

    2013-06-01

    report of FSW on a ferritic- martensitic stainless steel is the work of Chung, which applied this approach to a dissimilar weld between F82H (ferritic... martensitic ) and SUS304 (austenitic stainless ) [43]. 7 D. CORROSION OF FERRITIC/ MARTENSITIC STEELS IN HIGH TEMPERATURE MOLTEN SALT COOLANTS In...Philadelphia, PA, 1992, pp. 1267–1286, March 1990. [15] S. Rosenwasser, ―The application of martensitic stainless steels in a lifelong fusion first wall

  3. Sensitivity Analysis of Fatigue Crack Growth Model for API Steels in Gaseous Hydrogen.

    Science.gov (United States)

    Amaro, Robert L; Rustagi, Neha; Drexler, Elizabeth S; Slifka, Andrew J

    2014-01-01

    A model to predict fatigue crack growth of API pipeline steels in high pressure gaseous hydrogen has been developed and is presented elsewhere. The model currently has several parameters that must be calibrated for each pipeline steel of interest. This work provides a sensitivity analysis of the model parameters in order to provide (a) insight to the underlying mathematical and mechanistic aspects of the model, and (b) guidance for model calibration of other API steels.

  4. Steel. A handbook for materials research and engineering. Vol. 1. Fundamentals

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This STEEL Textbook is the outcome of reflections within the Materials Committee of the German Iron and Steel Institute on whether to republish the Manual of Special Steels, the highly commendable work by E. Houdremont. Discussions came to the conclusion, however, that for various reasons it was neither possible nor expedient simply to publish a follow-up edition of the famed Houdremont. To begin with and from today's vantage point, there no longer seemed to be any justification for restricting the work to special steels in the sense of the term as understood by E. Houdremont. The term ''special steel'' has never gained acceptance in official circles or standards. If we replace it by the term ''high-grade steel'', which is nowadays defined in standards, and this would appear permissible with certain qualifications, and if we bear in mind that the boundaries between high-grade steels and non-high-grade steels, the commercial and quality steels, although defined in standards (see part A), nonetheless in terms of engineering parameters are quite blurred, so it would seem only fitting for such as work to cover all the various grades of steel, also in view of the great significance of the non-high-grade steels. Because of the very many different grades of steel, this approach necessarily involves the collaboration of very many experts, in other words it entails a joint effort. Moreover, the vast, barely manageable quantity of literature in this field all of which can hardly be analysed by just one person, inevitably leads to the conclusion that there is a need to produce the new work as a joint effort. (orig.).

  5. Fracture Mechanisms in Steel Castings

    Directory of Open Access Journals (Sweden)

    Stradomski Z.

    2013-09-01

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

  6. Semisolid forming of S48C steel grade

    Science.gov (United States)

    Plata, Gorka; Lozares, Jokin; Azpilgain, Zigor; Hurtado, Iñaki; Loizaga, Iñigo; Idoyaga, Zuriñe

    2017-10-01

    Steel production and component manufacturing industries have to face the challenge of globalization, trying to overcome the economic pressure to remain competitive. Moreover, the lightweighting trend of the latter years implies an even higher challenge to maintain the steel use. Therefore, advanced manufacturing processes will be the cornerstone. In this field, Semisolid forming (SSF) has demonstrated the capability of obtaining complex geometries and saving raw material and energy. Despite it is complicated the SSF of sound components, in Mondragon Unibertsitatea it has been successfully demonstrated the capability of producing strong enough automotive components with 42CrMo4 steel grade. In this work, we demonstrate the capability of SSF S48C steel grade with great mechanical properties.

  7. Corrosion of reinforcement bars in steel ibre reinforced concrete structures

    DEFF Research Database (Denmark)

    Solgaard, Anders Ole Stubbe

    and the influence of steel fibres on initiation and propagation of cracks in concrete. Moreover, the impact of fibres on corrosion-induced cover cracking was covered. The impact of steel fibres on propagation of reinforcement corrosion was investigated through studies of their impact on the electrical resistivity...... of concrete, which is known to affect the corrosion process of embedded reinforcement. The work concerning the impact of steel fibres on initiation and propagation of cracks was linked to corrosion initiation and propagation of embedded reinforcement bars via additional studies. Cracks in the concrete cover...... are known to alter the ingress rate of depassivating substances and thereby influence the corrosion process. The Ph.D. study covered numerical as well as experimental studies. Electrochemically passive steel fibres are electrically isolating thus not changing the electrical resistivity of concrete, whereas...

  8. Nanotribological behavior of deep cryogenically treated martensitic stainless steel

    Directory of Open Access Journals (Sweden)

    Germán Prieto

    2017-08-01

    Full Text Available Cryogenic treatments are increasingly used to improve the wear resistance of various steel alloys by means of transformation of retained austenite, deformation of virgin martensite and carbide refinement. In this work the nanotribological behavior and mechanical properties at the nano-scale of cryogenically and conventionally treated AISI 420 martensitic stainless steel were evaluated. Conventionally treated specimens were subjected to quenching and annealing, while the deep cryogenically treated samples were quenched, soaked in liquid nitrogen for 2 h and annealed. The elastic–plastic parameters of the materials were assessed by nanoindentation tests under displacement control, while the friction behavior and wear rate were evaluated by a nanoscratch testing methodology that it is used for the first time in steels. It was found that cryogenic treatments increased both hardness and elastic limit of a low-carbon martensitic stainless steel, while its tribological performance was enhanced marginally.

  9. Nanotribological behavior of deep cryogenically treated martensitic stainless steel.

    Science.gov (United States)

    Prieto, Germán; Bakoglidis, Konstantinos D; Tuckart, Walter R; Broitman, Esteban

    2017-01-01

    Cryogenic treatments are increasingly used to improve the wear resistance of various steel alloys by means of transformation of retained austenite, deformation of virgin martensite and carbide refinement. In this work the nanotribological behavior and mechanical properties at the nano-scale of cryogenically and conventionally treated AISI 420 martensitic stainless steel were evaluated. Conventionally treated specimens were subjected to quenching and annealing, while the deep cryogenically treated samples were quenched, soaked in liquid nitrogen for 2 h and annealed. The elastic-plastic parameters of the materials were assessed by nanoindentation tests under displacement control, while the friction behavior and wear rate were evaluated by a nanoscratch testing methodology that it is used for the first time in steels. It was found that cryogenic treatments increased both hardness and elastic limit of a low-carbon martensitic stainless steel, while its tribological performance was enhanced marginally.

  10. Texture developed during deformation of Transformation Induced Plasticity (TRIP) steels

    International Nuclear Information System (INIS)

    Bhargava, M; Asim, T; Sushil, M; Shanta, C

    2015-01-01

    Automotive industry is currently focusing on using advanced high strength steels (AHSS) due to its high strength and formability for closure applications. Transformation Induced Plasticity (TRIP) steel is promising material for this application among other AHSS. The present work is focused on the microstructure development during deformation of TRIP steel sheets. To mimic complex strain path condition during forming of automotive body, Limit Dome Height (LDH) tests were conducted and samples were deformed in servo hydraulic press to find the different strain path. FEM Simulations were done to predict different strain path diagrams and compared with experimental results. There is a significant difference between experimental and simulation results as the existing material models are not applicable for TRIP steels. Micro texture studies were performed on the samples using EBSD and X-RD techniques. It was observed that austenite is transformed to martensite and texture developed during deformation had strong impact on limit strain and strain path. (paper)

  11. Texture developed during deformation of Transformation Induced Plasticity (TRIP) steels

    Science.gov (United States)

    Bhargava, M.; Shanta, C.; Asim, T.; Sushil, M.

    2015-04-01

    Automotive industry is currently focusing on using advanced high strength steels (AHSS) due to its high strength and formability for closure applications. Transformation Induced Plasticity (TRIP) steel is promising material for this application among other AHSS. The present work is focused on the microstructure development during deformation of TRIP steel sheets. To mimic complex strain path condition during forming of automotive body, Limit Dome Height (LDH) tests were conducted and samples were deformed in servo hydraulic press to find the different strain path. FEM Simulations were done to predict different strain path diagrams and compared with experimental results. There is a significant difference between experimental and simulation results as the existing material models are not applicable for TRIP steels. Micro texture studies were performed on the samples using EBSD and X-RD techniques. It was observed that austenite is transformed to martensite and texture developed during deformation had strong impact on limit strain and strain path.

  12. Hydrogen effects in stainless steel

    International Nuclear Information System (INIS)

    Caskey, G.R. Jr.

    1983-01-01

    The effects of hydrogen on stainless steels have been reviewed and are summarized in this paper. Discussion covers hydrogen solution and transport in stainless steels as well as the effects of hydrogen on deformation and fracture under various loading conditions. Damage is caused also by helium that arises from decay of the hydrogen isotope tritium. Austenitic, ferritic, martensite, and precipitation-hardenable stainless steels are included in the discussion. 200 references

  13. [Characteristics of working conditions at metallurgy-related plants].

    Science.gov (United States)

    Egorova, A M

    2008-01-01

    Working conditions at more versus less advanced technology steel plants of the Volgograd Region are analyzed. The working conditions at the less advanced technology plants are referred to as a very high occupational risk. It is necessary to work out measures to lower the poor impact of microclimate, dust, noise, to improve illumination, and to regulate labor at steel plants.

  14. Bulk nanoscale materials in steel products

    International Nuclear Information System (INIS)

    Chehab, B; Wang, X; Masse, J-P; Zurob, H; Embury, D; Bouaziz, O

    2010-01-01

    Although a number of nanoscale metallic materials exhibit interesting mechanical properties the fabrication paths are often complex and difficult to apply to bulk structural materials. However a number of steels which exhibit combinations of plasticity and phase transitions can be deformed to produce ultra high strength levels in the range 1 to 3 GPa. The resultant high stored energy and complex microstructures allow new nanoscale structures to be produced by combinations of recovery and recrystallisation. The resultant structures exhibit totally new combinations of strength and ductility to be achieved. In specific cases this also enables both the nature of the grain boundary structure and the spatial variation in structure to be controlled. In this presentation both the detailed microstructural features and their relation to the strength, work-hardening capacity and ductility will be discussed for a number of martensitic and austenitic steels.

  15. Mobbing and harassment in the steel enterprises

    Directory of Open Access Journals (Sweden)

    J. Vveinhardt

    2017-01-01

    Full Text Available Mobbing and harassment are widely analysed in organizations providing various services but are little studied in the companies undertaking industrial activities. Therefore, the aim of the paper is to diagnose the prevalence of mobbing and harassment in the steel enterprises. The case study analysis of the largest steel producer in the world, and specifically its division in Poland was used to determine the prevalence of these phenomena. It was found out that the said company is the example of the ethically and socially responsible organization. However, the interviews indicate that single cases of mobbing and harassment activities (though relatively rare were also observed. They were distributed among three groups of employees: 1 those who do physical work (are directly engaged in the production process; 2 employees involved in the administrative activity and sales; and 3 managerial staff.

  16. Weld repair of creep damaged steels

    International Nuclear Information System (INIS)

    Croker, A.B.L.; Harrison, R.P.; Moss, C.J.

    1995-01-01

    A cooperative research centre project 'Welding of Thermally Modified Structures' was commenced in June 1993 with support from ANSTO, CSIRO, BHP, University of Wollongong and the CRC for Materials, Welding and Joining. The main aims of the project are to quantify the effects of performing repair welds on materials which have operated for extended periods at elevated temperature. Welding is an increasingly used method for performing repairs, replacements, retrofits and modifications to elevated temperature plant, however, the effects of these repairs on the ultimate life of a component are poorly understood. This paper presents details of the three ex-service materials chosen for the project, a carbon steel and two alloy steels. Work is also presented on development of new methods of assessing materials and components both destructively, along with new methods of modelling welded components in high temperature service. 6 figs, 3 tabs

  17. Performance and working life of cathodic protection systems for concrete structures

    NARCIS (Netherlands)

    Polder, R.B.; Worm, D.; Courage, W.; Leegwater, G.

    2012-01-01

    Corrosion of reinforcing steel in concrete structures causes concrete cracking and steel diameter reduction, eventually resulting in loss of safety. Conventional repair means heavy, labour intensive and costly work and the required quality level is under economic pressure. Consequently, conventional

  18. Research on NDT Technology in Inference of Steel Member Strength Based on Macro/Micro Model

    Directory of Open Access Journals (Sweden)

    Beidou Ding

    2017-01-01

    Full Text Available In consideration of correlations among hardness, chemical composition, grain size, and strength of carbon steel, a new nondestructive testing technology (NDT of inferring the carbon steel strength was explored. First, the hardness test, chemical composition analysis, and metallographic analysis of 162 low-carbon steel samples were conducted. Second, the following works were carried out: (1 quantitative relationship between steel Leeb hardness and carbon steel strength was studied on the basis of regression analysis of experimental data; (2 influences of chemical composition and grain size on tension properties of carbon steel were analyzed on the basis of stepwise regression analysis, and quantitative relationship between conventional compositions and grain size with steel strength was obtained; (3 according to the macro and/or micro factors such as hardness, chemical compositions, and grain size of carbon steel, the fitting formula of steel strength was established based on MLR (multiple linear regressions method. The above relationships and fitting formula based on MLR method could be used to estimate the steel strength with no damage to the structure in engineering practice.

  19. The Effect of Different Non-Metallic Inclusions on the Machinability of Steels.

    Science.gov (United States)

    Ånmark, Niclas; Karasev, Andrey; Jönsson, Pär Göran

    2015-02-16

    Considerable research has been conducted over recent decades on the role of non‑metallic inclusions and their link to the machinability of different steels. The present work reviews the mechanisms of steel fractures during different mechanical machining operations and the behavior of various non-metallic inclusions in a cutting zone. More specifically, the effects of composition, size, number and morphology of inclusions on machinability factors (such as cutting tool wear, power consumption, etc .) are discussed and summarized. Finally, some methods for modification of non-metallic inclusions in the liquid steel are considered to obtain a desired balance between mechanical properties and machinability of various steel grades.

  20. Analyse and research of nonmetallic inclusions for steel 100Cr6

    Directory of Open Access Journals (Sweden)

    I. Vitez

    2009-01-01

    Full Text Available Steel 100Cr6 belongs to a group of hardened steels, which are applicable for production of rolling element parts. Because of specific working conditions, a proper chemical composition is required with a minimum content of nonmetallic inclusion. In this paper, the research results of presence the nonmetallic inclusions and their chemical composition are presented for the steel produced in vacuum and open induction electric furnace and their influence on the prescribed properties for this steel. The optical and scanning electronic microscope are used to identify presence and the chemical compositions of nonmetallic inclusions.

  1. The industrial ecology of steel

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-03-26

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

  2. Stainless steels low temperature nitriding

    International Nuclear Information System (INIS)

    Roux, T.; Darbeida, A.; Von Stebut, J.; Michel, H.; Lebrun, J.P.; Hertz, D.

    1995-01-01

    Nitrogen ions implantation of 316L stainless steel leads to monophasic diffusion layers, which are constituted of a solid solution (γ N ) fcc, metastable, nitrogen sur-saturated, and without order. This article shows that for 316L stainless steels,these layers improve the tribological properties without degradation of the corrosion resistance. (A.B.). 13 refs. 6 figs

  3. Metadynamic recrystallization in C steels

    Indian Academy of Sciences (India)

    Unknown

    EN24 and EN2 steels, a drop from 4000 s to 6 s for similar temperature rise was observed. Metadynamic ... carbon–manganese or silicon–manganese steels, but stops after a reduction at ... growth by strain-induced grain boundary migration;.

  4. Mechanics in Steels through Microscopy

    NARCIS (Netherlands)

    Tirumalasetty, G.K.

    2013-01-01

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

  5. A Tale of Wootz Steel

    Indian Academy of Sciences (India)

    manufacture of steel in south India by a crucible process at ... indicates that the production of wootz steel was almost on an industrial scale in ... in an Age of Design marked by ... The Russian Anasoff also studied the process of manufacturing.

  6. Irradiation creep in ferritic steels

    International Nuclear Information System (INIS)

    Vandermeulen, W.; Bremaecker, A. de; Burbure, S. de; Huet, J.J.; Asbroeck, P. van

    Pressurized and non-pressurized capsules of several ferritic steels have been irradiated in Rapsodie between 400 and 500 0 C up to 3.7 x 10 22 n/cm 2 (E>0.1 MeV). Results of the diameter measurements are presented and show that the total in-pile deformation is lower than for austenitic steels

  7. Steel structures for nuclear facilities

    International Nuclear Information System (INIS)

    1993-01-01

    In the guide the requirements concerning design and fabrication of steel structures for nuclear facilities and documents to be submitted to the Finnish Centre for Radiation and Nuclear Safety (STUK) are presented. Furthermore, regulations concerning inspection of steel structures during construction of nuclear facilities and during their operation are set forth

  8. Microstructural characterization of cermet-steel interface in rock drilling tool

    International Nuclear Information System (INIS)

    Ybarra, L.A.C.; Molisani, A.L.; Yoshimura, H.N.

    2010-01-01

    Rock drilling tools basically present a WC cermet bonded to a steel shank. The interface cermet-steel plays fundamental role during drilling operation, since the fracture of this interface is the main failure mode of the tools. In this work, the microstructure of this interface in crown samples (type A), prepared in an industrial like process, was evaluated. In this process, a WC-containing powder was infiltrated with a copper alloy at 1100 deg C in a graphite mold previously mounted with a 1020 steel tube. The powder was characterized by XRD analysis and the cross-section microstructure of cermet-steel was analyzed using SEM-EDS. It was observed that Ni and small amount of Cu from cermet matrix diffused into the superficial region of the steel, and the Cu alloy dissolved and penetrated along the steel grain boundaries, resulting in good metallurgical bonding of the interface.(author)

  9. Behavior of helium gas atoms and bubbles in low activation 9Cr martensitic steels

    Science.gov (United States)

    Hasegawa, Akira; Shiraishi, Haruki; Matsui, Hideki; Abe, Katsunori

    1994-09-01

    The behavior of helium-gas release from helium-implanted 9Cr martensitic steels (500 appm implanted at 873 K) during tensile testing at 873 K was studied. Modified 9Cr-1Mo, low-activation 9Cr-2W and 9Cr-0.5V were investigated. Cold-worked AISI 316 austenitic stainless steel was also investigated as a reference which was susceptible helium embrittlement at high temperature. A helium release peak was observed at the moment of rupture in all the specimens. The total quantity of helium released from these 9Cr steels was in the same range but smaller than that of 316CW steel. Helium gas in the 9Cr steels should be considered to remain in the matrix at their lath-packets even if deformed at 873 K. This is the reason why the martensitic steels have high resistance to helium embrittlement.

  10. Carbon steel protection in G.S. (Girlder sulfide) plants. CITROSOLV process influence. Pt. 6

    International Nuclear Information System (INIS)

    Lires, O.A.; Burkart, A.L.; Delfino, C.A.; Rojo, E.A.

    1988-01-01

    In order to protect carbon steel towers and piping of Girlder sulfide (G.S.) experimental heavy water plants against corrosion produced by the action of aqueous solutions of hydrogen sulfides, a method, previously published, was developed. Carbon steel, exposed to saturated aqueous solutions of hydrogen sulfide, forms iron sulfide scales. In oxygen free solutions evolution of corrosion follows the sequence: mackinawite → cubic ferrous sulfide → troilite → pyrrotite → pyrite. Scales formed by pyrrotite-pyrite or pyrite are the most protective layers (these are obtained at 130 deg C, 2 MPa, for periods of 14 days). CITROSOLV Process (Pfizer) is used to descaling and passivating stainless steel plant's components. This process must be used in mixed (carbon steel - stainless steel) circuits and may cause the formation of magnetite scales over the carbon steel. The influence of magnetite in the pyrrotite-pyrite scales formation is studied in this work. (Author) [es

  11. Mechanical Properties and Fractographic Analysis of High Manganese Steels After Dynamic Deformation Tests

    Directory of Open Access Journals (Sweden)

    Jabłońska M.B.

    2014-10-01

    Full Text Available Since few years many research centres conducting research on the development of high-manganese steels for manufacturing of parts for automotive and railway industry. Some of these steels belong to the group of AHS possessing together with high strength a great plastic elongation, and an ideal uniform work hardening behavior. The article presents the dynamic mechanical properties of two types of high manganese austenitic steel with using a flywheel machine at room temperature with strain rates between 5×102÷3.5×103s?–1. It was found that the both studied steels exhibit a high sensitivity Rm to the strain rate. With increasing the strain rate from 5×102 to 3.5×103s?–1 the hardening dominates the process. The fracture analysis indicate that after dynamic test both steel is characterized by ductile fracture surfaces which indicate good plasticity of investigated steels.

  12. Behavior of helium gas atoms and bubbles in low activation 9Cr martensitic steels

    International Nuclear Information System (INIS)

    Hasegawa, Akira; Shiraishi, Haruki; Matsui, Hideki; Abe, Katsunori

    1994-01-01

    The behavior of helium-gas release from helium-implanted 9Cr martensitic steels (500 appm implanted at 873 K) during tensile testing at 873 K was studied. Modified 9Cr-1Mo, low-activation 9Cr-2W and 9Cr-0.5V were investigated. Cold-worked AISI 316 austenitic stainless steel was also investigated as a reference which was susceptible helium embrittlement at high temperature. A helium release peak was observed at the moment of rupture in all the specimens. The total quantity of helium released from these 9Cr steels was in the same range but smaller than that of 316CW steel. Helium gas in the 9Cr steels should be considered to remain in the matrix at their lath-packets even if deformed at 873 K. This is the reason why the martensitic steels have high resistance to helium embrittlement. ((orig.))

  13. Evaluation of properties of low activation Mn-Cr steel. 3. Evaluation of corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Shigeru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Fukaya, Kiyoshi [Nihon Advanced Technology Co., Ltd., Tokai, Ibaraki (Japan); Ishiyama, Shintaro [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Sato, Ikuo; Kusuhashi, Mikio; Hatakeyama, Takeshi [Japan Steel Works Ltd., Muroran, Hokkaido (Japan). Muroran Plant; Takahashi, Heishichiro [Hokkaido Univ., Sapporo, Hokkaido (Japan); Kikuchi, Mitsuru [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2002-05-01

    JAERI and the Japan Steel Works LTD. (JSW) have developed new Mn-Cr steels as low induced activation material. Until now, chemical composition and metallurgical processes were optimized and some steels named VC-series were selected. The properties of the steels have been evaluated and reported elsewhere. In this study, corrosion resistance of VC-series was studied. Corrosion tests for stainless steels were performed to investigate a relationship between corrosion rate and chemical composition or sensitization. Furthermore, corrosion tests under actual environment for the vacuum vessel of the reinforced JT-60 were done for non-magnetic steels. As a result, almost no weight change was observed for uniform and gap corrosion tests, No crack was shown for double U-bend corrosion tests. (author)

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

    International Nuclear Information System (INIS)

    Pereloma, E.V.; Bata, V.; Scott, R.I.; Smith, R.M.

    2010-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Pereloma, E.V., E-mail: elenap@uow.edu.au [School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522 (Australia); Bata, V. [Department of Materials Engineering, Monash University (Australia); Scott, R.I.; Smith, R.M. [BlueScope Steel Limited, Port Kembla (Australia)

    2010-04-25

    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 {approx}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.

  16. Development of high yield strength non-magnetic steels for the equipments of nuclear fusion research

    International Nuclear Information System (INIS)

    Matsuoka, Hidenori; Mukai, Tetsuya; Ohtani, Hiroo; Tsuruki, Takanori; Okada, Yasutaka

    1979-01-01

    Recently, activity of nuclear fusion research and so forth increase the demand of non-magnetic materials for various equipments and structures. For these usage, very low magnetic permeability as well as high strength are required under high magnetic field. Based on fundamental research, middle C-17% Cr-7% Ni-N non-magnetic steel has been developed. The developed steel shows more stable austenite phase and possesses higher yield strength and endurance limit of more than 10 kg/mm 2 , compared with 18% Cr-8% Ni austenitic steel. Also the developed steel has good ductility and toughness in spite of the high yield strength and shows better machinability than usual high Mn non- magnetic steels. The large forgings of this newly developed steel are manufactured in the works for the equipments of nuclear fusion research and confirmed good mechanical properties, high fatigue strength and low permeability. (author)

  17. AWWA C303-17 concrete pressure pipe, bar-wrapped, steel-cylinder type

    CERN Document Server

    2017-01-01

    This standard describes the manufacture of concrete pressure pipe, reinforced with a steel cylinder that is helically wrapped with mild steel bar reinforcement, in sizes ranging from 10 in. through 72 in. (250 mm through 1,830 mm), inclusive, and for working pressures up to 400 psi (2,760 kPa).

  18. Steel-Industry of the Future; Industrial Partnerships: Advancing Energy and Environmental Goals

    International Nuclear Information System (INIS)

    Jones, A.

    2001-01-01

    This tri-fold brochure describe the partnering activities of the Office of Industrial Technologies' (OIT) Industries of the Future (IOF) for Steel. Information on what works for the Steel industry, examples of successful partnerships, and benefits of partnering with OIT are included

  19. Electromagnetic NDT to characterize usage properties of flat steel products

    Energy Technology Data Exchange (ETDEWEB)

    Altpeter, I.; Dobmann, G.; Szielasko, K., E-mail: iab.altlau@t-online.de, E-mail: gerd.dobmann@t-online.de, E-mail: klaus.szielasko@izfp.fraunhofer.de [Fraunhofer Inst. - IZFP, Saarbruecken (Germany)

    2015-07-15

    The Fraunhofer Institute for Non-destructive Testing (IZFP) in Saarbruecken, Germany, started its activities in materials characterization of flat steel products in the eighties of the last century in the basic program of the European Community of Coal and Steel (ECCS). Throughout the years, continuous research and development were performed. The objective of the work, presented within this three-part series of reports, is to discuss the history of an innovation which began in 1988 with R&D in the area of texture characterization in steel sheets produced for car-body manufacturing (Part 1). In the following years the activities were to automate online property determination in terms of yield strength, tensile strength, planar, and vertical-anisotropy-factors. Again, steel sheets were the focus of the developments and the first NDT systems that came into industrial application for this project. Parallel research was performed to characterize the mechanical properties and hardness of heavy steel plates, mainly produced for pipeline manufacturing and off-shore applications (Part 2) The final report in the series (Part 3) will discuss steel sheet characterization and presents the successful development of a combination-transducer which combines ultrasonics with electromagnetic NDT. (author)

  20. Flexural Cracking Behavior Of Steel Fiber Reinforced Concrete Beams

    Directory of Open Access Journals (Sweden)

    Ashraf Abdalkader

    2017-08-01

    Full Text Available Steel fibers are added to concrete due to its ability to improve the tensile strength and control propagation of cracks in reinforced concrete members. Steel fiber reinforced concrete is made of cement fine water and coarse aggregate in addition to steel fibers. In this experimental work flexural cracking behavior of reinforced concrete beams contains different percentage of hooked-end steel fibers with length of 50 mm and equivalent diameter of 0.5 mm was studied. The beams were tested under third-point loading test at 28 days. First cracking load maximum crack width cracks number and load-deflection relations were investigated to evaluate the flexural cracking behavior of concrete beams with 34 MPa target mean strength. Workability wet density compressive and splitting tensile strength were also investigated. The results showed that the flexural crack width is significantly reduced with the addition of steel fibers. Fiber contents of 1.0 resulted in 81 reduction in maximum crack width compared to control concrete without fiber. The results also showed that the first cracking load and maximum load are increased with the addition of steel fibers.

  1. Electromagnetic NDT to characterize usage properties of flat steel products

    International Nuclear Information System (INIS)

    Altpeter, I.; Dobmann, G.; Szielasko, K.

    2015-01-01

    The Fraunhofer Institute for Non-destructive Testing (IZFP) in Saarbruecken, Germany, started its activities in materials characterization of flat steel products in the eighties of the last century in the basic program of the European Community of Coal and Steel (ECCS). Throughout the years, continuous research and development were performed. The objective of the work, presented within this three-part series of reports, is to discuss the history of an innovation which began in 1988 with R&D in the area of texture characterization in steel sheets produced for car-body manufacturing (Part 1). In the following years the activities were to automate online property determination in terms of yield strength, tensile strength, planar, and vertical-anisotropy-factors. Again, steel sheets were the focus of the developments and the first NDT systems that came into industrial application for this project. Parallel research was performed to characterize the mechanical properties and hardness of heavy steel plates, mainly produced for pipeline manufacturing and off-shore applications (Part 2) The final report in the series (Part 3) will discuss steel sheet characterization and presents the successful development of a combination-transducer which combines ultrasonics with electromagnetic NDT. (author)

  2. Tribological Response of Heat Treated AISI 52100 Steels Against Steel and Ceramic Counterparts

    Directory of Open Access Journals (Sweden)

    Türedi E.

    2017-09-01

    Full Text Available AISI 52100 bearing steels are commonly used in applications requiring high hardness and abrasion resistance. The bearing steels are working under dynamic loads in service conditions and their toughness properties become important. In order to provide the desired mechanical properties, various heat treatments (austenizing, quenching and tempering are usually applied. In this study, AISI 52100 bearing steel samples were austenized at 900°C for ½ h and water quenched to room temperature. Then tempering was carried out at 795°C, 400°C and 200°C for ½ h. In order to investigate the effect of heat treatment conditions on wear behavior, dry friction tests were performed according to ASTM G99-05 Standard with a ‘ball-on-disk’ type tribometer. The samples were tested against steel and ceramic counterparts using the parameters of 100 m distance and 30 N load and 0.063 m/s rotational speed. After wear test, the surface characterization was carried out using microscopy. Wear loss values were calculated using a novel optical method on both flat and counterpart specimens.

  3. Spark Plasma Co-Sintering of Mechanically Milled Tool Steel and High Speed Steel Powders

    Directory of Open Access Journals (Sweden)

    Massimo Pellizzari

    2016-06-01

    Full Text Available Hot work tool steel (AISI H13 and high speed steel (AISI M3:2 powders were successfully co-sintered to produce hybrid tool steels that have properties and microstructures that can be modulated for specific applications. To promote co-sintering, which is made difficult by the various densification kinetics of the two steels, the particle sizes and structures were refined by mechanical milling (MM. Near full density samples (>99.5% showing very fine and homogeneous microstructure were obtained using spark plasma sintering (SPS. The density of the blends (20, 40, 60, 80 wt % H13 was in agreement with the linear rule of mixtures. Their hardness showed a positive deviation, which could be ascribed to the strengthening effect of the secondary particles altering the stress distribution during indentation. A toughening of the M3:2-rich blends could be explained in view of the crack deviation and crack arrest exerted by the H13 particles.

  4. Ionic nitriding of high chromium martensitic stainless steels

    International Nuclear Information System (INIS)

    Bruhl, S.P; Charadia, R; Vaca, L.S; Cimetta, J

    2008-01-01

    Martensitic stainless steels are used in industrial applications where resistance to corrosion and mechanical resistance are needed simultaneously. These steels are normally used in tempering and annealing condition which gives them hardnesses of 500 and 600 HV (about 54 HRC). Ionic nitriding is an assisted diffusion technique that has recently been successfully applied to harden austenitic stainless steels without reducing their resistance to corrosion. The application with AISI 420 martensitic steels has not given good results yet, because in most cases, it affects their corrosion resistance. This work presents the results of the pulsed nitriding of martensitic steels with a higher chrome content, such as the M340 and M333 Boehler steels and they are compared with the same materials after tempering and annealing, without nitriding. The influence of the variations in the parameters of the process, such as the percentage of active time in the pulsed wave, partial nitrogen pressure, current density and effective tension in the microstructure, hardness and wear and corrosion resistance was studied. The microstructure was studied with an optic microscope; the wear resistance with abrasion tests following ASTM G-65 and corrosion with 100 hour long saline haze tests, in a device built according to ASTM B117. Hardness was found to rise to values of 1000 to 1350 HV in all the steels after ionic nitriding, the modified layers oscillated from 3 to 15 microns. As a result, wear resistance also increased, with differences depending on the microstructure and the thickness of the modified layer. However, corrosion resistance was not good, except in the case of the M333 steel test piece with less hardness and a less thick nitrided layer without a noticeable interphase (au)

  5. A flat solar collector built from galvanized steel plate, working by thermosyphonic flow, optimized for Mexican conditions; Un colector solar plano construido de lamina de acero galvanizada, operando por flujo termosifonico, optimizado para las condiciones mexicanas

    Energy Technology Data Exchange (ETDEWEB)

    Marroquin de Jesus, A; Olivares Ramirez, J.M.; Ramos Lopez, G.A.; Pless, R.C. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Instituto Politecnico Nacional, Unidad Queretaro (Mexico)]. E-mail: amarroquind@utsjr.edu.mx

    2009-07-15

    Design, construction, and testing of the thermal performance of a flat solar collector for domestic water heating are described. The absorbing plate is built from readily available materials: two sheets of galvanized steel, one of the channelled types, the other one flat, which are joined by electric welding. The absorber is connected to a 198-L thermotank, insulated with polyurethane foam. In terms of receiving surface, the prototype tested here has an area of 1.35 m{sup 2}, about 20% smaller than comparable copper-tube-based collectors offered in the market. Temperature measurements conducted over a 30-day period gave values which were a few degrees lower than the theoretically calculated water temperatures. Momentary thermal efficiency values between 35% and 77% were observed. The water temperature achieved the tank at the end of the day averages 65 degrees Celsius in winter weather conditions in the central Mexican highland. This design of solar water heater is well suited to Mexican conditions, as it makes use of the high local intensity of the solar radiation, and as the channel shape of the ducts minimizes bursting during the rare occurrences of freezing temperatures in the region; it also has the advantage of being manufacturable at low cost from simple materials. [Spanish] Se describe el diseno, construccion y pruebas del desempeno termico de un colector solar plano para calentamiento de agua para uso domestico. La placa absorbedora se construyo de materiales facilmente asequibles: dos placas de acero galvanizado, una del tipo acanalado y la otra plana, unidas mediante soldadura de acero electrico. La placa absorbedora esta conectada a un termotanque con capacidad de 198 L, aislado con espuma de poliuretano. La superficie receptora de este prototipo es de 1.35 m{sup 2}, aproximadamente 20% mas pequena comparado con los colectores, basados en tubos de cobre, ofertados en el mercado. Mediciones de temperatura por un periodo de 30 dias, arrojaron valores

  6. Connections: Superplasticity, Damascus Steels, Laminated Steels, and Carbon Dating

    Science.gov (United States)

    Wadsworth, Jeffrey

    2016-12-01

    In this paper, a description is given of the connections that evolved from the initial development of a family of superplastic plain carbon steels that came to be known as Ultra-High Carbon Steels (UHCS). It was observed that their very high carbon contents were similar, if not identical, to those of Damascus steels. There followed a series of attempts to rediscover how the famous patterns found on Damascus steels blades were formed. At the same time, in order to improve the toughness at room temperature of the newly-developed UHCS, laminated composites were made of alternating layers of UHCS and mild steel (and subsequently other steels and other metals). This led to a study of ancient laminated composites, the motives for their manufacture, and the plausibility of some of the claims relating to the number of layers in the final blades. One apparently ancient laminated composite, recovered in 1837 from the great pyramid of Giza which was constructed in about 2750 B.C., stimulated a carbon dating study of ancient steels. The modern interest in "Bladesmithing" has connections back to many of these ancient weapons.

  7. Stiffness of Railway Soil-Steel Structures

    Directory of Open Access Journals (Sweden)

    Machelski Czesław

    2015-12-01

    Full Text Available The considerable influence of the soil backfill properties and that of the method of compacting it on the stiffness of soil-steel structures is characteristic of the latter. The above factors (exhibiting randomness become apparent in shell deformation measurements conducted during construction and proof test loading. A definition of soil-shell structure stiffness, calculated on the basis of shell deflection under the service load, is proposed in the paper. It is demonstrated that the stiffness is the inverse of the deflection influence function used in structural mechanics. The moving load methodology is shown to be useful for testing, since it makes it possible to map the shell deflection influence line also in the case of group loads (concentrated forces, as in bridges. The analyzed cases show that the shell’s span, geometry (static scheme and the height of earth fill influence the stiffness of the structure. The soil-steel structure’s characteristic parameter in the form of stiffness k is more suitable for assessing the quality of construction works than the proposed in code geometric index ω applied to beam structures. As shown in the given examples, parameter k is more effective than stiffness parameter λ used to estimate the deformation of soil-steel structures under construction. Although the examples concern railway structures, the methodology proposed in the paper is suitable also for road bridges.

  8. Impact Testing of Stainless Steel Materials

    International Nuclear Information System (INIS)

    R. K. Blandford; D. K. Morton; T. E. Rahl; S. D. Snow

    2005-01-01

    Stainless steels are used for the construction of numerous spent nuclear fuel or radioactive material containers that may be subjected to high strains and moderate strain rates (10 to 200 per second) during accidental drop events. Mechanical characteristics of these materials under dynamic (impact) loads in the strain rate range of concern are not well documented. The goal of the work presented in this paper was to improve understanding of moderate strain rate phenomena on these materials. Utilizing a drop-weight impact test machine and relatively large test specimens (1/2-inch thick), initial test efforts focused on the tensile behavior of specific stainless steel materials during impact loading. Impact tests of 304L and 316L stainless steel test specimens at two different strain rates, 25 per second (304L and 316L material) and 50 per second (304L material) were performed for comparison to their quasi-static tensile test properties. Elevated strain rate stress-strain curves for the two materials were determined using the impact test machine and a ''total impact energy'' approach. This approach considered the deformation energy required to strain the specimens at a given strain rate. The material data developed was then utilized in analytical simulations to validate the final elevated stress-strain curves. The procedures used during testing and the results obtained are described in this paper

  9. Hot flow behavior of boron microalloyed steels

    International Nuclear Information System (INIS)

    Lopez-Chipres, E.; Mejia, I.; Maldonado, C.; Bedolla-Jacuinde, A.; El-Wahabi, M.; Cabrera, J.M.

    2008-01-01

    This research work studies the effect of boron contents on the hot flow behavior of boron microalloyed steels. For this purpose, uniaxial hot-compression tests were carried out in a low carbon steel microalloyed with four different amounts of boron over a wide range of temperatures (950, 1000, 1050 and 1100 deg. C) and constant true strain rates (10 -3 , 10 -2 and 10 -1 s -1 ). Experimental results revealed that both peak stress and peak strain tend to decrease as boron content increases, which indicates that boron additions have a solid solution softening effect. Likewise, the flow curves show a delaying effect on the kinetics of dynamic recrystallization (DRX) when increasing boron content. Deformed microstructures show a finer austenitic grain size in the steel with higher boron content (grain refinement effect). Results are discussed in terms of boron segregation towards austenitic grain boundaries during plastic deformation, which increases the movement of dislocations, enhances the grain boundary cohesion and modificates the grain boundary structure

  10. Stiffness of Railway Soil-Steel Structures

    Science.gov (United States)

    Machelski, Czesław

    2015-12-01

    The considerable influence of the soil backfill properties and that of the method of compacting it on the stiffness of soil-steel structures is characteristic of the latter. The above factors (exhibiting randomness) become apparent in shell deformation measurements conducted during construction and proof test loading. A definition of soil-shell structure stiffness, calculated on the basis of shell deflection under the service load, is proposed in the paper. It is demonstrated that the stiffness is the inverse of the deflection influence function used in structural mechanics. The moving load methodology is shown to be useful for testing, since it makes it possible to map the shell deflection influence line also in the case of group loads (concentrated forces), as in bridges. The analyzed cases show that the shell's span, geometry (static scheme) and the height of earth fill influence the stiffness of the structure. The soil-steel structure's characteristic parameter in the form of stiffness k is more suitable for assessing the quality of construction works than the proposed in code geometric index ω applied to beam structures. As shown in the given examples, parameter k is more effective than stiffness parameter λ used to estimate the deformation of soil-steel structures under construction. Although the examples concern railway structures, the methodology proposed in the paper is suitable also for road bridges.

  11. Influence of heat treatment on corrosive resistance of concrete steels

    International Nuclear Information System (INIS)

    Woldan, A.; Suliga, I.; Kusinski, J.; Jazowy, R.

    1998-01-01

    The reinforcing bars are essential elements of ferro-concrete structures. During the building structure service the reinforcing bars should co-operate with surrounding concrete. Any bonding defects as well as corrosion induced strength reduction may result in construction failure. The reinforcing steel working environment is determined by concrete chemical and phase composition and surrounding environmental properties. The aggressive corrosive activity of the letter implies necessity of effective ways development to protect elements against corrosion. The effect of heat treatment, increased Si content in steel on corrosion resistance of reinforcing steel in concrete was studied in the current work. Corrosion tests and metallographic examinations proved a positive influence of hardening and Si enrichment on corrosion resistance of reinforcing bars in ferro-concrete structures. (author)

  12. Utilization of FEM model for steel microstructure determination

    Science.gov (United States)

    Kešner, A.; Chotěborský, R.; Linda, M.; Hromasová, M.

    2018-02-01

    Agricultural tools which are used in soil processing, they are worn by abrasive wear mechanism cases by hard minerals particles in the soil. The wear rate is influenced by mechanical characterization of tools material and wear rate is influenced also by soil mineral particle contents. Mechanical properties of steel can be affected by a technology of heat treatment that it leads to a different microstructures. Experimental work how to do it is very expensive and thanks to numerical methods like FEM we can assumed microstructure at low cost but each of numerical model is necessary to be verified. The aim of this work has shown a procedure of prediction microstructure of steel for agricultural tools. The material characterizations of 51CrV4 grade steel were used for numerical simulation like TTT diagram, heat capacity, heat conduction and other physical properties of material. A relationship between predicted microstructure by FEM and real microstructure after heat treatment shows a good correlation.

  13. Development of liner cutting method for stainless steel liner

    International Nuclear Information System (INIS)

    Takahata, Masato; Wignarajah, Sivakmaran; Kamata, Hirofumi

    2005-01-01

    The present work is an attempt to develop a laser cutting method for cutting and removing stainless steel liners from concrete walls and floors in cells and fuel storage pools of nuclear facilities. The effects of basic laser cutting parameters such as cutting speed, assist gas flow etc. were first studied applying a 1 kW Nd:YAG laser to mock up concrete specimens lined with 3 mm thick stainless steel sheets. These initial studies were followed by studies on the effect of unevenness of the liner surface and on methods of confining contamination during the cutting process. The results showed that laser cutting is superior to other conventional cutting methods from the point of view of safety from radioactivity and work efficiency when cutting contaminated stainless steel liners. In addition to the above results, this paper describes the design outline of a laser cutting system for cutting stainless liners at site and evaluates its merit and cost performance. (author)

  14. Development of laser cutting method for stainless steel liner

    International Nuclear Information System (INIS)

    Ishihara, Satoshi; Takahata, Masato; Wignarajah, Sivakumaran; Kamata, Hirofumi

    2007-01-01

    The present work is an attempt to develop a laser cutting method for cutting and removing stainless steel liners from concrete walls and floors in nuclear facilities. The effect of basic laser cutting parameters such as energy, cutting speed, assist gas flow etc. were first studied through cutting experiments on mock-up concrete specimens lined with 3mm thick stainless steel sheets using a 1kW Nd:YAG laser. These initial studies were followed by further studies on the effect of unevenness of the liner surface and on a new method of confining contamination during the cutting process using a sliding evacuation hood attached to the laser cutting head. The results showed that laser cutting is superior to other conventional cutting methods from the point of view of safety from radioactivity and work efficiency when cutting contaminated stainless steel liners. (author)

  15. Additively manufactured hierarchical stainless steels with high strength and ductility

    Science.gov (United States)

    Wang, Y. Morris; Voisin, Thomas; McKeown, Joseph T.; Ye, Jianchao; Calta, Nicholas P.; Li, Zan; Zeng, Zhi; Zhang, Yin; Chen, Wen; Roehling, Tien Tran; Ott, Ryan T.; Santala, Melissa K.; Depond, Philip J.; Matthews, Manyalibo J.; Hamza, Alex V.; Zhu, Ting

    2018-01-01

    Many traditional approaches for strengthening steels typically come at the expense of useful ductility, a dilemma known as strength-ductility trade-off. New metallurgical processing might offer the possibility of overcoming this. Here we report that austenitic 316L stainless steels additively manufactured via a laser powder-bed-fusion technique exhibit a combination of yield strength and tensile ductility that surpasses that of conventional 316L steels. High strength is attributed to solidification-enabled cellular structures, low-angle grain boundaries, and dislocations formed during manufacturing, while high uniform elongation correlates to a steady and progressive work-hardening mechanism regulated by a hierarchically heterogeneous microstructure, with length scales spanning nearly six orders of magnitude. In addition, solute segregation along cellular walls and low-angle grain boundaries can enhance dislocation pinning and promote twinning. This work demonstrates the potential of additive manufacturing to create alloys with unique microstructures and high performance for structural applications.

  16. Behavior of stainless steels in pressurized water reactor primary circuits

    International Nuclear Information System (INIS)

    Féron, D.; Herms, E.; Tanguy, B.

    2012-01-01

    Stainless steels are widely used in primary circuits of pressurized water reactors (PWRs). Operating experience with the various grades of stainless steels over several decades of years has generally been excellent. Nevertheless, stress corrosion failures have been reported in few cases. Two main factors contributing to SCC susceptibility enhancement are investigated in this study: cold work and irradiation. Irradiation is involved in the stress corrosion cracking and corrosion of in-core reactor components in PWR environment. Irradiated assisted stress corrosion cracking (IASCC) is a complex and multi-physics phenomenon for which a predictive modeling able to describe initiation and/or propagation is not yet achieved. Experimentally, development of initiation smart tests and of in situ instrumentation, also in nuclear reactors, is an important axis in order to gain a better understanding of IASCC kinetics. A strong susceptibility for SCC of heavily cold worked austenitic stainless steels is evidenced in hydrogenated primary water typical of PWRs. It is shown that for a given cold-working procedure, SCC susceptibility of austenitic stainless steels materials increases with increasing cold-work. Results have shown also strong influences of the cold work on the oxide layer composition and of the maximum stress on the time to fracture.

  17. Occupational Profiles in the European Steel Industry.

    Science.gov (United States)

    Franz, Hans-Werner; And Others

    The steel industry in Europe has faced great changes, with resulting layoffs and restructuring. Now that the most basic changes seem to be over, it has become evident that the remaining steel industry requires more highly trained workers than was the case previously. Although steel maintenance employees were always highly skilled, steel production…

  18. Multicriteria Analysis of Assembling Buildings from Steel Frame Structures

    Science.gov (United States)

    Miniotaite, Ruta

    2017-10-01

    Steel frame structures are often used in the construction of public and industrial buildings. They are used for: all types of slope roofs; walls of newly-built public and industrial buildings; load bearing structures; roofs of renovated buildings. The process of assembling buildings from steel frame structures should be analysed as an integrated process influenced by such factors as construction materials and machinery used, the qualification level of construction workers, complexity of work, available finance. It is necessary to find a rational technological design solution for assembling buildings from steel frame structures by conducting a multiple criteria analysis. The analysis provides a possibility to evaluate the engineering considerations and find unequivocal solutions. The rational alternative of a complex process of assembling buildings from steel frame structures was found through multiple criteria analysis and multiple criteria evaluation. In multiple criteria evaluation of technological solutions for assembling buildings from steel frame structures by pairwise comparison method the criteria by significance are distributed as follows: durability is the most important criterion in the evaluation of alternatives; the price (EUR/unit of measurement) of a part of assembly process; construction workers’ qualification level (category); mechanization level of a part of assembling process (%), and complexity of assembling work (in points) are less important criteria.

  19. Methods of making bainitic steel materials

    Science.gov (United States)

    Bakas, Michael Paul; Chu, Henry Shiu-Hung; Zagula, Thomas Andrew; Langhorst, Benjamin Robert

    2018-01-16

    Methods of making bainitic steels may involve austenitizing a quantity of steel by exposing the quantity of steel to a first temperature. A composition of the quantity of steel may be configured to impede formation of non-bainite ferrite, pearlite, and Widmanstatten ferrite. The quantity of steel may be heat-treated to form bainite by exposing the quantity of steel to a second, lower temperature. The second, lower temperature may be stabilized by exposing the quantity of steel to the second, lower temperature in the presence of a thermal ballast.

  20. Stahlschüssel key to steel

    CERN Document Server

    Wegst, W S

    2016-01-01

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

  1. Advanced steel reheat furnace

    Energy Technology Data Exchange (ETDEWEB)

    Moyeda, D.; Sheldon, M.; Koppang, R. [Energy and Environmental Research Corp., Irvine, CA (United States); Lanyi, M.; Li, X.; Eleazer, B. [Air Products and Chemicals, Inc., Allentown, PA (United States)

    1997-10-01

    Energy and Environmental Research Corp. (EER) under a contract from the Department of Energy is pursuing the development and demonstration of an Advanced Steel Reheating Furnace. This paper reports the results of Phase 1, Research, which has evaluated an advanced furnace concept incorporating two proven and commercialized technologies previously applied to other high temperature combustion applications: EER`s gas reburn technology (GR) for post combustion NOx control; and Air Product`s oxy-fuel enrichment air (OEA) for improved flame heat transfer in the heating zones of the furnace. The combined technologies feature greater production throughput with associated furnace efficiency improvements; lowered NOx emissions; and better control over the furnace atmosphere, whether oxidizing or reducing, leading to better control over surface finish.

  2. Stainless steel decontamination manipulators

    International Nuclear Information System (INIS)

    Sullivan, R.J.

    1986-01-01

    Three, large-volume coverage manipulator systems were designed and built for the Defense Water Processing Facility at the Savannah River Laboratory. These stainless steel systems will be used for high-pressure spray decontamination of waste containers and large process equipment modules. Each system has a manipulator arm, folding boom, and vertical drive and guide structure. Handling capacity is 45 kg, horizontal reach is 4.6 m with a 180-deg swing motion, and the vertical travel is 6 m. The system is remotely removable and replaceable in modules using an overhead crane and an impact wrench. The manipulator arm has seven motions: Shoulder rotation and pivot, elbow pivot, wrist pivot and rotation, and grip open-close. All motions are variable speed and are slip-clutch protected to prevent overloading from external forces (collisions)

  3. Steel containment buckling

    International Nuclear Information System (INIS)

    Butler, T.A.; Baker, W.E.

    1987-01-01

    Two aspects of buckling of a free-standing nuclear containment building were investigated in a combined experimental and analytical program. In the first part of the study, the response of a scale model of a containment building to dynamic base excitation is investigated. A simple harmonic signal was used for preliminary studies followed by experiments with scaled earthquake signals as the excitation source. The experiments and accompanying analyses indicate that the scale model response to earthquake-type excitations is very complex and that current analytical methods may require that a dynamic capacity reduction factor be incorporated. The second part of the study quantified the effects of framing at large penetrations on the static buckling capacity of scale model containments. Results show little effect from the framing for the scale models constructed from the polycarbonate, Lexan. However, additional studies with a model constructed of the prototypic steel material are recommended. (orig.)

  4. Microstructural investigations of fast reactor irradiated austenitic and ferritic-martensitic stainless steel fuel cladding

    International Nuclear Information System (INIS)

    Agueev, V.S.; Medvedeva, E.A.; Mitrofanova, N.M.; Romanueev, V.V.; Tselishev, A.V.

    1992-01-01

    Electron microscopy has been used to characterize the microstructural changes induced in advanced fast reactor fuel claddings fabricated from Cr16Ni15Mo3NbB and Cr16Ni15Mo2Mn2TiVB austenitic stainless steels in the cold worked condition and Cr13Mo2NbVB ferritic -martensitic steel following irradiation in the BOR-60, BN-350 and BN-600 fast reactors. The data are compared with the results obtained from a typical austenitic commercial cladding material, Cr16Ni15Mo3Nb, in the cold worked condition. The results reveal a beneficial effect of boron and other alloying elements in reducing void swelling in 16Cr-15Ni type austenitic steels. The high resistance of ferritic-martensitic steels to void swelling has been confirmed in the Cr13Mo2NbVB steel. (author)

  5. Micropurity in stainless steel making

    International Nuclear Information System (INIS)

    Motloch, Z.

    1981-01-01

    New technologies were developed by the Vitkovice research institutes in response to high requirements for the quality of high-alloy steels for nuclear power, viz., duplex technology with double vacuum degassing at the DH unit and oxidation vacuum degassing using the VAKUVIT equipment. The steel produced shows low contents of impurities and high micropurity. A study was conducted into changes in carbon content and the formation of titanium nitrides and carbonitrides in austenitic steels during their production, and optimum technological parameters were found for eliminating their formation in forgings. (author)

  6. Steel fiber replacement of mild steel in prestressed concrete beams

    Science.gov (United States)

    2010-10-01

    In traditional prestressed concrete beams, longitudinal prestressed tendons serve to resist bending moment and : transverse mild steel bars (or stirrups) are used to carry shear forces. However, traditional prestressed concrete I-beams : exhibit earl...

  7. Steel fiber replacement of mild steel in prestressed concrete beams.

    Science.gov (United States)

    2011-01-01

    In traditional prestressed concrete beams, longitudinal prestressed tendons serve to resist bending moment and transverse mild : steel bars (or stirrups) are used to carry shear forces. However, traditional prestressed concrete I-beams exhibit early-...

  8. [The Steel factor].

    Science.gov (United States)

    Cáceres-Cortés, J R

    1997-01-01

    Mice bearing mutations at either of two loci, dominant White spotting(W) or Steel(Sl), exhibit development defects in hematopoietic, melanocytic and germ cells. Genetics studies have shown that the SI locus encodes the Steel factor (SF), which is the ligand for the tyrosine kinase receptor c-kit, the product of the W locus. SF is synthesized in membrane-bound form and can be processed to produce a soluble form. Cell-cell interaction is important in the production of normal blood cells in vivo and in vitro and in the cellular expansion of leukemic cells. We discuss here how SF decreases the requirements in cell interaction for blast colony formation in acute myeloblastic leukemia (AML) and the presence of membrane-bound SF possibly contributes to the density-dependent growth of the AML blasts. We explain that SF is mainly a survival factor for hematopoietic cells, of little proliferative effect, which maintains CD34+ hematopoietic cells in an undifferentiated state. These properties would potentially allow the maintenance of hematopoietic cells in culture for the purpose of marrow purging or gene therapy. The activation of the c-kit signal transduction pathway may play a significant role in the development of many types of non-hematological malignancies by disrupting normal cell-cell interactions and allowing the growth of cancer cell populations. In summary, the properties of the SF indicate it has a role for survival signals during the process of normal differentiation, AML proliferation and in the maintenance of many c-kit+ tumors.

  9. The effects of temperature and strain rate on the dynamic flow behaviour of different steels

    International Nuclear Information System (INIS)

    Lee, W.-S.; Liu, C.-Y.

    2006-01-01

    density increases linearly with the work hardening stress. The current results provide a valuable reference for the application of S15C low carbon steel, S50C medium carbon steel, and SKS93 high carbon steel in high-speed plastic forming processes

  10. Method of treating tool steel die materials

    International Nuclear Information System (INIS)

    Cook, C.S.; Damon, S.

    1981-01-01

    In a method of hardening pilger dies to provide a hard case containing residual compressive stresses and tough body, the tool steel die is heated to the austenitizing temperature range, followed by selectively removing heat from the die at a predetermined faster rate in the direction of the desired case than the rate of heat removal from the balance of the die, and thereafter tempering the die. The invention provides a fully hardened and tempered case on the working surface of the die and a tough body in the balance of the die, usually of lower hardness. (author)

  11. Measurement of gamma radioactivity in steel

    International Nuclear Information System (INIS)

    Wachtendonk, H.J. von; Flock, J.; Grientschnig, D.; Kircher, T.; Kroos, J.; Mertens, S.; Mueller, J.; Puchmayr, J.; Schlothmann, B.J.; Schmitz, H.U.; Troebs, V.; Unger, H.

    1999-01-01

    The steel industry is being confronted increasingly with radioactive scrap from dismantled nuclear facilities. The clearance and release regulations that exist around the world differ very greatly and are difficult to implement. A 'radioactivity measurement' working group has therefore been set up at VDEh to clarify how radioactive measurements can be integrated into the day-to-day production routine. Operating results obtained at Thyssen Krupp Stahl AG with a gamma-ray spectrometer indicate a possibility for the simple detection of radioactive contamination. (orig.) [de

  12. Composite layers in the high speed steels

    International Nuclear Information System (INIS)

    Koson, A.; Rutkowska, A.; Dabrowski, M.

    2002-01-01

    The production process and different properties of TiN, (TiA)(N and TiN + (TiAl)N coatings are described in this work. The coatings were obtained on fast-cutting steel 6-5-2(SW7M) after a typical heat treatment and gas nitriding. The following features were examined: thickness and hardness of produced layers as well as wearing quality (using T-0.5 tester). Composite layer of (TiAl)N has achieved the highest wearing quality in the range of wearing parameters applied. (author)

  13. Friction welding of steel to ceramic

    OpenAIRE

    Rombaut, Pieter; De Waele, Wim; Faes, Koenraad

    2011-01-01

    The goal of this paper is to give a clear summary of the literature review performed during the master thesis on friction welding on dissimilar materials. Of main interest for this work is the welding of steel to a ceramic material such as alumina (Al2O3). Because of the difficulties involved in producing a sound weld for this material combination, not a lot of literature is available on this topic. This paper starts with a discussion on the basics of friction welding and typical problems enc...

  14. Support systems for faces and workings (Le soutenement des tailles ou chantiers d'exploitation)

    Energy Technology Data Exchange (ETDEWEB)

    Stassen, P

    1978-01-01

    Various support systems for use in underground mining are discussed, these include: A. Props: wooden props, steel props and yielding props. B. Roofbars: wooden bars, solid steel bars, steel link bars, steel flange bars, cruciform steel bars. C. Chocks: working conditions, timber release chocks, steel-girder chocks, mechanical chocks and chock-type supports. D. Powered supports: classification of powered support systems, the parameters which have to be considered when selecting the right type of powered support, minimal load- bearing requirement for powered supports, characteristic features of some powered-support system. (10 refs.) (In French)

  15. Formation of Me–O–Si covalent bonds at the interface between polysilazane and stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Amouzou, Dodji, E-mail: adodji@gmail.com [Research Centre in Physics of Matter and Radiation (PMR), University of Namur, Rue de Bruxelles 61, 5000 Namur (Belgium); Fourdrinier, Lionel; Maseri, Fabrizio [CRM-Group, Boulevard de Colonster, B 57, 4000 Liège (Belgium); Sporken, Robert [Research Centre in Physics of Matter and Radiation (PMR), University of Namur, Rue de Bruxelles 61, 5000 Namur (Belgium)

    2014-11-30

    Highlights: • Natural metal-oxides, hydroxides are detected on the top surface of steel substrates we tested. • Polysilazane reacts with hydroxide functional groups on steel substrates to form Cr–O–Si and Fe–O–Si covalent bonds. • Covalent bonding between steel and polysilazane at the interface was probed using spectroscopic techniques. - Abstract: In earlier works, we demonstrated the potential of polysilazane (PSZ) coatings for a use as insulating layers in Cu(In,Ga)Se{sub 2} (CIGS) solar cells prepared on steels substrates and showed a good adhesion between PSZ coatings and both AISI316 and AISI430 steels. In the present paper, spectroscopic techniques are used to elucidate the reason of such adhesion. X-ray Photoelectron Spectroscopy (XPS) was used to investigate surfaces for the two steel substrates and showed the presence of metal oxides and metal hydroxides at the top surface. XPS has been also used to probe interfaces between substrates and PSZ, and metallosiloxane (Me–O–Si) covalent bonds have been detected. These results were confirmed by Infra-Red Reflection Absorption Spectroscopy (IRRAS) analyses since vibrations related to Cr–O–Si and Fe–O–Si compounds were detected. Thus, the good adhesion between steel substrates and PSZ coatings was explained by covalent bonding through chemical reactions between PSZ precursors and hydroxide functional groups present on top surface of the two types of steel. Based on these results, an adhesion mechanism between steel substrates and PSZ coatings is proposed.

  16. Current status and recent research achievements in ferritic/martensitic steels

    Science.gov (United States)

    Tavassoli, A.-A. F.; Diegele, E.; Lindau, R.; Luzginova, N.; Tanigawa, H.

    2014-12-01

    When the austenitic stainless steel 316L(N) was selected for ITER, it was well known that it would not be suitable for DEMO and fusion reactors due to its irradiation swelling at high doses. A parallel programme to ITER collaboration already had been put in place, under an IEA fusion materials implementing agreement for the development of a low activation ferritic/martensitic steel, known for their excellent high dose irradiation swelling resistance. After extensive screening tests on different compositions of Fe-Cr alloys, the chromium range was narrowed to 7-9% and the first RAFM was industrially produced in Japan (F82H: Fe-8%Cr-2%W-TaV). All IEA partners tested this steel and contributed to its maturity. In parallel several other RAFM steels were produced in other countries. From those experiences and also for improving neutron efficiency and corrosion resistance, European Union opted for a higher chromium lower tungsten grade, Fe-9%Cr-1%W-TaV steel (Eurofer), and in 1997 ordered the first industrial heats. Other industrial heats have been produced since and characterised in different states, including irradiated up to 80 dpa. China, India, Russia, Korea and US have also produced their grades of RAFM steels, contributing to overall maturity of these steels. This paper reviews the work done on RAFM steels by the fusion materials community over the past 30 years, in particular on the Eurofer steel and its design code qualification for RCC-MRx.

  17. Development of low-chromium, chromium-tungsten steels for fusion

    International Nuclear Information System (INIS)

    Klueh, R.L.; Alexander, D.J.; Kenik, E.A.

    1995-01-01

    High-chromium (9-12% Cr) Cr-Mo and Cr-W ferritic steels are favored as candidates for fusion applications. In early work to develop reduced-activation steels, an Fe-2.25Cr-2W-0.25V-0.1C steel (designated 2.25Cr-2WV) had better strength than an Fe-9Cr-2W-0.25V-0.07Ta-0.1C (9Cr-2WVTa) steel (compositions are in weight percent). However, the 2.25Cr-2WV had poor impact properties, as determined by the ductile-brittle transition temperature and upper-shelf energy of subsize Charpy impact specimens. Because low-chromium steels have some advantages over high-chromium steels, a program to develop low-chromium steels is in progress. Microstructural analysis indicated that the reason for the inferior impact toughness of the 2.25Cr-2WV was the granular bainite obtained when the steel was normalized. Properties can be improved by developing an acicular bainite microstructure by increasing the cooling rate after austenitization. Alternatively, acicular bainite can be promoted by increasing the hardenability. Hardenability was changed by adding small amounts of boron and additional chromium to the 2.25Cr-2WV composition. A combination of B, Cr, and Ta additions resulted in low-chromium reduced-activation steels with mechanical properties comparable to those of 9Cr-2WVTa. (orig.)

  18. Current status and recent research achievements in ferritic/martensitic steels

    Energy Technology Data Exchange (ETDEWEB)

    Tavassoli, A.-A.F., E-mail: farhad.tavassoli@cea.fr [Commissariat à l' Energie Atomique et aux Energies Alternatives, CEA/DEN/DANS/DMN, F-91191 Gif-sur-Yvette (France); Diegele, E., E-mail: eberhard.diegele@kit.edu [Karlsruhe Institut of Technology (KIT), Karlsruhe (Germany); Lindau, R., E-mail: rainer.lindau@kit.edu [Karlsruhe Institut of Technology (KIT), Karlsruhe (Germany); Luzginova, N., E-mail: Natalia.Luzginova@gmail.com [NRG-Petten, 1755 ZG Petten (Netherlands); Tanigawa, H., E-mail: tanigawa.hiroyasu@jaea.go.jp [Japan Atomic Energy Authority (JAEA), Tokai, Ibaraki, 319-1195 (Japan)

    2014-12-15

    When the austenitic stainless steel 316L(N) was selected for ITER, it was well known that it would not be suitable for DEMO and fusion reactors due to its irradiation swelling at high doses. A parallel programme to ITER collaboration already had been put in place, under an IEA fusion materials implementing agreement for the development of a low activation ferritic/martensitic steel, known for their excellent high dose irradiation swelling resistance. After extensive screening tests on different compositions of Fe–Cr alloys, the chromium range was narrowed to 7–9% and the first RAFM was industrially produced in Japan (F82H: Fe–8%Cr–2%W–TaV). All IEA partners tested this steel and contributed to its maturity. In parallel several other RAFM steels were produced in other countries. From those experiences and also for improving neutron efficiency and corrosion resistance, European Union opted for a higher chromium lower tungsten grade, Fe–9%Cr–1%W–TaV steel (Eurofer), and in 1997 ordered the first industrial heats. Other industrial heats have been produced since and characterised in different states, including irradiated up to 80 dpa. China, India, Russia, Korea and US have also produced their grades of RAFM steels, contributing to overall maturity of these steels. This paper reviews the work done on RAFM steels by the fusion materials community over the past 30 years, in particular on the Eurofer steel and its design code qualification for RCC-MRx.

  19. A Goal Programming Optimization Model for The Allocation of Liquid Steel Production

    Science.gov (United States)

    Hapsari, S. N.; Rosyidi, C. N.

    2018-03-01

    This research was conducted in one of the largest steel companies in Indonesia which has several production units and produces a wide range of steel products. One of the important products in the company is billet steel. The company has four Electric Arc Furnace (EAF) which produces liquid steel which must be procesed further to be billet steel. The billet steel plant needs to make their production process more efficient to increase the productvity. The management has four goals to be achieved and hence the optimal allocation of the liquid steel production is needed to achieve those goals. In this paper, a goal programming optimization model is developed to determine optimal allocation of liquid steel production in each EAF, to satisfy demand in 3 periods and the company goals, namely maximizing the volume of production, minimizing the cost of raw materials, minimizing maintenance costs, maximizing sales revenues, and maximizing production capacity. From the results of optimization, only maximizing production capacity goal can not achieve the target. However, the model developed in this papare can optimally allocate liquid steel so the allocation of production does not exceed the maximum capacity of the machine work hours and maximum production capacity.

  20. International comparisons of energy efficiency in power, steel, and cement industries

    International Nuclear Information System (INIS)

    Oda, Junichiro; Akimoto, Keigo; Tomoda, Toshimasa; Nagashima, Miyuki; Wada, Kenichi; Sano, Fuminori

    2012-01-01

    Industrial energy efficiency is of paramount importance both for conserving energy resources and reducing CO 2 emissions. In this paper, we compare specific energy consumption among countries in fossil power generation, steel, and cement sectors. The evaluations were conducted using common system boundaries, allocation, and calculation methods. In addition, we disaggregate within sectors, such as with blast furnace–basic oxygen furnace (BF–BOF) steel and scrap-based electric arc furnace (Scrap-EAF) steel. The results reveal that characteristics vary by sub-sector. Regional differences in specific energy consumption are relatively large in the power, BF–BOF steel, and cement sectors. For coal power generation and BF–BOF steel production, continual maintenance and rehabilitation are of key importance. We confirm these key factors identified in the previous work on our estimated numerical values. In BF–BOF steel production, corrections for hot metal ratios (pig iron production per unit of BOF crude steel production) and quality of raw materials have a large effect on the apparent specific energy consumption. Available data is not yet sufficient for straightforward evaluation of the steel and cement sectors. - Highlights: ► We compare energy efficiency among countries in power, steel, and cement sectors. ► In steel and cement sectors, the results are provided in terms of specific energy consumption (GJ/ton of product). ► We distinguish BOF steel and EAF steel. ► New installation and continual maintenance are the key for energy efficiency. ► Corrections have a large impact on apparent specific energy consumption.

  1. SIMS depth profiling of working environment nanoparticles

    Science.gov (United States)

    Konarski, P.; Iwanejko, I.; Mierzejewska, A.

    2003-01-01

    Morphology of working environment nanoparticles was analyzed using sample rotation technique in secondary ion mass spectrometry (SIMS). The particles were collected with nine-stage vacuum impactor during gas tungsten arc welding (GTAW) process of stainless steel and shielded metal arc welding (SMAW) of mild steel. Ion erosion of 300-400 nm diameter nanoparticles attached to indium substrate was performed with 2 keV, 100 μm diameter, Ar + ion beam at 45° ion incidence and 1 rpm sample rotation. The results show that both types of particles have core-shell morphology. A layer of fluorine, chlorine and carbon containing compounds covers stainless steel welding fume particles. The cores of these particles are enriched in iron, manganese and chromium. Outer shell of mild steel welding fume particles is enriched in carbon, potassium, chlorine and fluorine, while the deeper layers of these nanoparticles are richer in main steel components.

  2. SIMS depth profiling of working environment nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Konarski, P.; Iwanejko, I.; Mierzejewska, A

    2003-01-15

    Morphology of working environment nanoparticles was analyzed using sample rotation technique in secondary ion mass spectrometry (SIMS). The particles were collected with nine-stage vacuum impactor during gas tungsten arc welding (GTAW) process of stainless steel and shielded metal arc welding (SMAW) of mild steel. Ion erosion of 300-400 nm diameter nanoparticles attached to indium substrate was performed with 2 keV, 100 {mu}m diameter, Ar{sup +} ion beam at 45 deg. ion incidence and 1 rpm sample rotation. The results show that both types of particles have core-shell morphology. A layer of fluorine, chlorine and carbon containing compounds covers stainless steel welding fume particles. The cores of these particles are enriched in iron, manganese and chromium. Outer shell of mild steel welding fume particles is enriched in carbon, potassium, chlorine and fluorine, while the deeper layers of these nanoparticles are richer in main steel components.

  3. Austenitic stainless steel bulk property considerations for fusion reactors

    International Nuclear Information System (INIS)

    Mattas, R.F.

    1979-04-01

    The bulk properties of annealed 304, 316, and 20% cold-worked 316 stainless steels are evaluated for the temperature and radiation conditions expected in a near-term fusion reactor. Of interest are the thermophysical properties, void swelling produced by neutron radiaion, and the tensile, creep, and fatigue properties before and after irradiation

  4. 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.

  5. Reality based optimization of steel monopod offshore-towers

    NARCIS (Netherlands)

    Vrouwenvelder, A.C.W.M.

    2008-01-01

    In this work, the implementation of reliability-based optimization (RBO) of a circular steel monopod-offshore-tower with constant and variable diameters (represented by segmentations) and thicknesses is presented. The tower is subjected to the extreme wave loading. For this purpose, the

  6. Optimization of steel monopod offshore-towers under probabilistic constraints

    NARCIS (Netherlands)

    Vrouwenvelder, A.C.W.M.

    2008-01-01

    In this work, economical design implementation of a circular steel monopod-offshore-tower, which is subjected to the extreme wave loading, is presented. The mass of the tower is considered as the objective function. The thickness and radius of the cross-section of the tower are adopted as design

  7. Structural changes in polytetrafluoroethylene molecular chains upon sliding against steel

    NARCIS (Netherlands)

    Shen, J.T.; Pei, Y.T.; Hosson, J.Th.M. De

    In this work, the influence of dry sliding between a steel counterpart ball and polytetrafluoroethylene (PTFE) plate sample on the transformation of PTFE molecular structure is investigated. With X-ray diffraction, differential scanning calorimetry, Fourier transform infrared (FT-IR) spectroscopy

  8. Response of neutron-irradiated RPV steels to thermal annealing

    International Nuclear Information System (INIS)

    Iskander, S.K.; Sokolov, M.A.; Nanstad, R.K.

    1997-01-01

    One of the options to mitigate the effects of irradiation on reactor pressure vessels (RPVs) is to thermally anneal them to restore the fracture toughness properties that have been degraded by neutron irradiation. This paper summarizes experimental results of work performed at the Oak Ridge National Laboratory (ORNL) to study the annealing response of several irradiated RPV steels

  9. A study of DLC coatings for ironing of stainless steel

    DEFF Research Database (Denmark)

    Sulaiman, Mohd Hafis Bin; Christiansen, Peter; Bay, Niels Oluf

    2017-01-01

    severe lubrication conditions by adopting strip reduction testing to replicate industrial ironing production of deep drawn, stainless steel cans. Three DLC coatings are investigated; multi-layer, double layer and single layer. Experiments revealed that the double layer coating worked successful, i...

  10. Transformation in austenitic stainless steel sheet under different loading directions

    NARCIS (Netherlands)

    van den Boogaard, Antonius H.; Krauer, J.; Hora, P.

    2011-01-01

    The stress-strain relation for austenitic stainless steels is based on 2 main contributions: work hardening and a phase transformation from austenite to martensite. The transformation is highly temperature dependent. In most models for phase transformation from austenite to martensite, the stress

  11. Transformation in Austenitic Stainless Steel Sheet under Different Loading Directions

    NARCIS (Netherlands)

    van den Boogaard, Antonius H.; Krauer, J.; Hora, P.

    2011-01-01

    The stress-strain relation for austenitic stainless steels is based on 2 main contributions: work hardening and a phase transformation from austenite to martensite. The transformation is highly temperature dependent. In most models for phase transformation from austenite to martensite, the stress

  12. Framework for replacing steel with aluminum fibers in bituminous mixes

    NARCIS (Netherlands)

    Pavlatos, N.; Apostolidis, P.; Scarpas, Athanasios

    2018-01-01

    This research explores the incentives for replacing steel fibers with aluminum fibers in fiber modified bituminous mixes. In this work the focus is on fiber modified bituminous mixes especially designed for induction heating. Inductive fibers are heated up because eddy currents are generated -

  13. 75 FR 27428 - Safety Standards for Steel Erection

    Science.gov (United States)

    2010-05-17

    ... Engineer must prepare and seal working drawings for falsework in many cases. OSHA believes that knowledge... rule; technical amendment. SUMMARY: This technical amendment adds a nonmandatory note to the OSHA... Administration regulations that may apply to employers engaged in activities covered by OSHA's steel erection...

  14. A quality approach to maintain the properties of S235 JR structural carbon steel in Lebanon

    International Nuclear Information System (INIS)

    Sidawi, J.A.; Al Khatib, H.

    2004-01-01

    Full text.S235JR carbon steel is one of the most popular steels used in Lebanon. It is imported by steel dealers and is widely used by all fabricators and manufacturers of steels for many structural purposes and applications. This kind of steel has good ductile properties as well as excellent weldability. It is still known by its previous designation St 37-2 or E 24-2. S235JR is produced in many shapes and thicknesses such as steel plates, sheets, angles and different other geometric shapes. Standard chemical and mechanical tests were conducted and reported on S235JR hot-rolled structural low-carbon mild steel specimens collected from Lebanese steel market. The main objective of this work is to assure the compliance of these properties with those set by the steel manufacturer. The above mentioned tests were performed at the laboratories of the Industrial Research Institute (IR) in Lebanon to assure the quality and credibility of the results. related European and American standards were presented as references and compared with the achieved results. Discussion was presented to show the similarities and differences between S235JR steel samples and standard requirements. Some of the reasons for such differences were discussed. Sufficient data was furnished through this work for the public and mainly for the Lebanese Standard Organization LIBNOR to easily adopt and implement the EN 10025:1993 European standard that can be applied in Lebanon concerning the most commonly used hot rolled low carbon structural steel. A follow up concerning adopting and implementing EN 10025:1993 will be briefed

  15. Abrasive Wear Resistance of Tool Steels Evaluated by the Pin-on-Disc Testing

    Science.gov (United States)

    Bressan, José Divo; Schopf, Roberto Alexandre

    2011-05-01

    Present work examines tool steels abrasion wear resistance and the abrasion mechanisms which are one main contributor to failure of tooling in metal forming industry. Tooling used in cutting and metal forming processes without lubrication fails due to this type of wear. In the workshop and engineering practice, it is common to relate wear resistance as function of material hardness only. However, there are others parameters which influences wear such as: fracture toughness, type of crystalline structure and the occurrence of hard precipitate in the metallic matrix and also its nature. In the present investigation, the wear mechanisms acting in tool steels were analyzed and, by normalized tests, wear resistance performance of nine different types of tool steels were evaluated by pin-on-disc testing. Conventional tool steels commonly used in tooling such as AISI H13 and AISI A2 were compared in relation to tool steels fabricated by sintering process such as Crucible CPM 3V, CPM 9V and M4 steels. Friction and wear testing were carried out in a pin-on-disc automated equipment which pin was tool steel and the counter-face was a abrasive disc of silicon carbide. Normal load of 5 N, sliding velocity of 0.45 m/s, total sliding distance of 3000 m and room temperature were employed. The wear rate was calculated by the Archard's equation and from the plotted graphs of pin cumulated volume loss versus sliding distance. Specimens were appropriately heat treated by quenching and three tempering cycles. Percentage of alloying elements, metallographic analyses of microstructure and Vickers microhardness of specimens were performed, analyzed and correlated with wear rate. The work is concluded by the presentation of a rank of tool steel wear rate, comparing the different tool steel abrasion wear resistance: the best tool steel wear resistance evaluated was the Crucible CPM 9V steel.

  16. Austenitic stainless steel weld inspection

    International Nuclear Information System (INIS)

    Mech, S.J.; Emmons, J.S.; Michaels, T.E.

    1978-01-01

    Analytical techniques applied to ultrasonic waveforms obtained from inspection of austenitic stainless steel welds are described. Experimental results obtained from a variety of geometric and defect reflectors are presented. Specifically, frequency analyses parameters, such as simple moments of the power spectrum, cross-correlation techniques, and adaptive learning network analysis, all represent improvements over conventional time domain analysis of ultrasonic waveforms. Results for each of these methods are presented, and the overall inspection difficulties of austenitic stainless steel welds are discussed

  17. High-strength maraging steels

    International Nuclear Information System (INIS)

    Grachev, S.V.; Shejn, A.S.

    1989-01-01

    Analysis of data on technological and operation properties of maraging steels on Fe-Cr-Ni, Fe-Ni, Fe-Cr-Co-Mo bases is given. Their advantages and drawbacks are pointed out. The scheme of strengthening heat treatment is considered. The fields of the most effective application of maraging steels for instance, for products operating under conditions of low-cycle and shock cyclic loading are mentioned

  18. Steel refining possibilities in LF

    Science.gov (United States)

    Dumitru, M. G.; Ioana, A.; Constantin, N.; Ciobanu, F.; Pollifroni, M.

    2018-01-01

    This article presents the main possibilities for steel refining in Ladle Furnace (LF). These, are presented: steelmaking stages, steel refining through argon bottom stirring, online control of the bottom stirring, bottom stirring diagram during LF treatment of a heat, porous plug influence over the argon stirring, bottom stirring porous plug, analysis of porous plugs disposal on ladle bottom surface, bottom stirring simulation with ANSYS, bottom stirring simulation with Autodesk CFD.

  19. MICROALLOYED STEELS FOR THE AUTOMOTIVE INDUSTRY

    Directory of Open Access Journals (Sweden)

    Debanshu Bhattacharya

    2014-12-01

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

  20. Problems with radioactivity scrap in the iron and steel industry of the Czech and Slovak Republics

    International Nuclear Information System (INIS)

    Raab, J.; Toman, V.

    1999-01-01

    During the recent restructuring process, the Czech steel industry has undergone a drastic reduction in the steel production by around 40%. Under such situation, previously exported volumes have been diverted into domestic markets. For the export, the Czech steel industry had to make its efforts in enhancing the quality of products and in improving the technologies in accordance with ISO standards (ISO 9000 and also ISO 14000). Among the various new quality demands in the export market, the radioactive contamination of steel products has received a very high attention. The Czech Iron and Steel Federation has organized a working team specialized in solving the problems arising from radioactive contaminated metallurgical scrap and steel products. The working team is made up of specialists from steel producers and scrap handling firms of the Czech Republic and the Slovak Republic, of experts from the State Office for Nuclear Safety, the Ministry of Industry and Trade and the Metrological Institute. Members of the Inspectorate for Ionizing Radiation and the General Directory for Customs are also included. This working team takes part in the elaboration of the legislative norms in that area. This paper deals with all the detailed functions of the working team. At present, all the major Czech steel producers have installed stationary radiation monitoring systems for detecting the possible radioactivity in all materials entering into factories. Under an agreement arranged between the producers of the Czech Iron and Steel Federation, the tolerable range of radionuclide contents in steel scrap and steel products has been set at the maximum of 100 Bq/kg in ( scrap and steel products. In this respect, the large firms collecting and treating scrap have also installed stationary radiation monitoring systems. In such monitoring systems, the detector will measure and check the values of radioactivity above 10 - 15% higher than the natural background level. In the case that

  1. Rolling Contact Fatigue Performances of Carburized and High-C Nanostructured Bainitic Steels

    Directory of Open Access Journals (Sweden)

    Yanhui Wang

    2016-11-01

    Full Text Available In the present work, the nanostructured bainitic microstructures were obtained at the surfaces of a carburized steel and a high-C steel. The rolling contact fatigue (RCF performances of the two alloy steels with the same volume fraction of undissolved carbide were studied under lubrication. Results show that the RCF life of the carburized nanostructured bainitic steel is superior to that of the high-C nanostructured bainitic steel in spite of the chemical composition, phase constituent, plate thickness of bainitic ferrite, hardness, and residual compressive stress value of the contact surfaces of the two steels under roughly similar conditions. The excellent RCF performance of the carburized nanostructured bainitic steel is mainly attributed to the following reasons: finer carbide dispersion distribution in the top surface, the higher residual compressive stress values in the carburized layer, the deeper residual compressive stress layer, the higher work hardening ability, the larger amount of retained austenite transforming into martensite at the surface and the more stable untransformed retained austenite left in the top surface of the steel.

  2. Rolling Contact Fatigue Performances of Carburized and High-C Nanostructured Bainitic Steels.

    Science.gov (United States)

    Wang, Yanhui; Zhang, Fucheng; Yang, Zhinan; Lv, Bo; Zheng, Chunlei

    2016-11-25

    In the present work, the nanostructured bainitic microstructures were obtained at the surfaces of a carburized steel and a high-C steel. The rolling contact fatigue (RCF) performances of the two alloy steels with the same volume fraction of undissolved carbide were studied under lubrication. Results show that the RCF life of the carburized nanostructured bainitic steel is superior to that of the high-C nanostructured bainitic steel in spite of the chemical composition, phase constituent, plate thickness of bainitic ferrite, hardness, and residual compressive stress value of the contact surfaces of the two steels under roughly similar conditions. The excellent RCF performance of the carburized nanostructured bainitic steel is mainly attributed to the following reasons: finer carbide dispersion distribution in the top surface, the higher residual compressive stress values in the carburized layer, the deeper residual compressive stress layer, the higher work hardening ability, the larger amount of retained austenite transforming into martensite at the surface and the more stable untransformed retained austenite left in the top surface of the steel.

  3. A review of hot cracking in austenitic stainless steel weldments

    International Nuclear Information System (INIS)

    Shankar, V.; Gill, T.P.S.; Mannan, S.L.; Rodriguez, P.

    1991-01-01

    The occurrence of hot cracking in austenitic stainless steel weldments is discussed with respect to its origin and metallurgical contributory factors. Of the three types of hot cracking, namely solidification cracking, liquation and ductility dip cracking, solidification cracking occurs in the interdendritic regions in weld metal while liquation and ductility dip cracking occur intergranularly in the heat-affected zone (HAZ). Segregation of impurity and minor elements such as sulphur, phosphorous, silicon, niobium, boron etc to form low melting eutectic phases has been found to be the major cause of hot cracking. Control of HAZ cracking requires minimisation of impurity elements in the base metal. In stabilized stainless steels containing niobium, higher amounts of delta-ferrite have been found necessary to prevent cracking than in unstabilized compositions. Titanium compounds have been found to cause liquation cracking in maraging steels and titanium containing stainless steels and superalloys. In nitrogen added stainless steels, cracking resistance decreases when the solidification mode changes to primary austenitic due to nitrogen addition. A review of the test methods to evaluate hot cracking behaviour showed that several external restraint and semi-self-restraint tests are available. The finger Test, WRC Fissure Bend Test, the PVR test and the Varestraint Test are described along with typical test results. Hot ductility testing to reveal HAZ cracking tendency during welding is described, which is of particular importance to stabilized stainless steels. Based on the literature, recommendations are made for welding stabilized and nitrogen added steels, indicating areas of further work. (author). 81 refs., 30 figs., 1 tab

  4. Testing and assessment of low alloy steel for marine application

    International Nuclear Information System (INIS)

    Amjad, M.; Ahmad, S.; Mahmood, K.; Qureshi, A.H.

    2007-01-01

    This paper is an account of the work carried out during the assessment of low alloy steel (WH-80) for marine application. The relevant acceptance criteria consulted during the process is DEFST AN 02-874 and a standard reference material. Assessment is based on the experimental results of the tests carried out for the steel. Testing comprised of mechanical (tensile, impact and hardness) tests, corrosion (immersion corrosion and stress corrosion cracking) tests, metallography test and weldability (weld joint strength, controlled thermal severity -CTS and Y -Groove) tests undertaken at various testing laboratories in Pakistan. The results obtained after testing have been compared with acceptance criteria (DEFSTAN 02-874 and standard reference material). Moreover results have been compared with contemporary steels used for marine applications. Results showed a reasonable agreement with results available in literature for other low alloy steels with respect to mechanical strength and weldability. Steel weldments qualified the weld joint strength tests and weldability tests. Toughness has been measured at various temperatures. Results revealed that the toughness of base metal is higher than heat affected zone (HAZ) and weld metal. In weldability tests, weld metal and HAZ were examined microscopically to investigate integrity of weld. No cracks have been observed in the weld which indicates complete diffusion in to the welding material. WH- 80 steel has exhibited comparatively high corrosion rate, reduction in tensile strength during SCC test and low Charpy energy values at -50 degree C. It is therefore concluded that the WH-80 steel is unsuitable for use in application at subzero (OC) temperatures and in highly corrosive environment. (author)

  5. Steel castings of valves for nuclear power station

    International Nuclear Information System (INIS)

    Yamasaki, Yutaka

    1975-01-01

    The manufacturing of the steel castings of valves for nuclear power plants is reported. The report is divided in six parts. The first part describes the reliability of the steel castings of valves for nuclear power plants. Particular attention must be paid to larger diameter and lower pressure rating for the valves in nuclear power plants than those in thermal power plants. The second part describes the characteristics of steel casting quality, defects and their cause. The defects that may be produced in steel castings are as follows: (a) cavities caused by the insufficient supply of molten steel, (b) sand bites caused by the mold destruction due to thermal shock, and (c) pinholes caused by the gas absorption of molten steel. The third part describes the clarification of quality level and the measures quality project. Gaseous defects and the indications detected by magnetic powder test are attributed to electric furnace steel making. In particular, the method to minimize gas content is important. The fourth part describes the quality control of manufacturing processes. In practice, thirteen semi-automatic testers using gamma radiation are employed. A full automatic inspection plant having capacity of 20,000 radiographs per month is under design. The fifth part describes a quality warrant system. A check sheet system concerning quality and safety is employed in all work shops. The reliability of all testers and measuring instruments as well as the skill of workmen are examined periodically. The seventh part deals with future problems. The manufacturing plan must be controlled so that non-destructive inspection becomes the main means for quality control. (Iwakiri, K.)

  6. The Structure of the Silumin Coat on Alloy Cast Steels

    Directory of Open Access Journals (Sweden)

    T. Szymczak

    2012-04-01

    Full Text Available The work presents the analysis results of the structure of the coat obtained by dipping in silumin AlSi5 of two grades of alloy cast steel: GX6CrNiTi18-10 (LH18N9T and GX39Cr13 (LH14. The temperature of the silumin bath was 750±5°C, and the hold-up time of the cast steel element τ = 180 s. The absolute thickness of the coat obtained in the given conditions was g = 104 μm on cast steel GX6CrNiTi18-10 and g = 132 μm on GX39Cr13. The obtained coat consisted of three layers of different phase structure. The first layer from the base “g1`” was constructed of the phase AlFe including Si and alloy additives of the tested cast steel grades: Cr and Ni (GX6CrNiTi18-10 and Cr (GX39Cr13. The second layer “g1``” of intermetallic phases AlFe which also contains Si and Cr crystallizes on it. The last, external layer “g2” of the coat consists of the silumin containing the intermetallic phases AlFeSi which additionally can contain alloy additives of the cast steel. It was shown that there were no carbides on the coat of the tested cast steels which are the component of their microstructure, as it took place in the case of the coat on the high speed steels.

  7. Topographical Anisotropy and Wetting of Ground Stainless Steel Surfaces

    Directory of Open Access Journals (Sweden)

    Cornelia Bellmann

    2012-12-01

    Full Text Available Microscopic and physico-chemical methods were used for a comprehensive surface characterization of different mechanically modified stainless steel surfaces. The surfaces were analyzed using high-resolution confocal microscopy, resulting in detailed information about the topographic properties. In addition, static water contact angle measurements were carried out to characterize the surface heterogeneity of the samples. The effect of morphological anisotropy on water contact angle anisotropy was investigated. The correlation between topography and wetting was studied by means of a model of wetting proposed in the present work, that allows quantifying the air volume of the interface water drop-stainless steel surface.

  8. Oxidation of 1020 steel in the abnormal glow discharge

    International Nuclear Information System (INIS)

    Zúñiga, J A García; Santos, A Sarmiento; Gómez, E Y Soto

    2017-01-01

    1020 steel is a material very used for surface treatment in the abnormal glow discharge. Because the composition of the gaseous atmosphere has an important influence on the results of plasma treatment, in this work the oxidation process of 1020 steel is verified on the abnormal glow discharge under different concentrations of air (20% to 100%) at temperatures of 600°C and 900°C. For each atmosphere used mass variation is measured during the process of surface oxidation, the structure and microstructure of the oxide film formed is observed and also its mechanical properties through its microhardness. (paper)

  9. Intergranular stress corrosion in soldered joints of stainless steel 304

    International Nuclear Information System (INIS)

    Zamora R, L.

    1994-01-01

    The intergranular stress cracking of welded joints of austenitic stainless steel, AISI 304, is a serious problem in BWR type reactors. It is associated with the simultaneous presence of three factors; stress, a critical media and sensibilization (DOS). EPR technique was used in order to verify the sensibilization degree in the base metal, and the zone affected by heat and welding material. The characterization of material was done. The objective of this work is the study of microstructure and the evaluation of EPR technique used for the determination of DOS in a welded plate of austenitic stainless steel AISI 304. (Author)

  10. Dissolution corrosion of 316L austenitic stainless steels in contact with static liquid lead-bismuth eutectic (LBE) at 500 °C

    Science.gov (United States)

    Lambrinou, Konstantina; Charalampopoulou, Evangelia; Van der Donck, Tom; Delville, Rémi; Schryvers, Dominique

    2017-07-01

    This work addresses the dissolution corrosion behaviour of 316L austenitic stainless steels. For this purpose, solution-annealed and cold-deformed 316L steels were simultaneously exposed to oxygen-poor (steels than the solution-annealed steel, indicating the importance of the steel thermomechanical state. The thickness of the dissolution-affected zone was non-uniform, and sites of locally-enhanced dissolution were occasionally observed. The progress of LBE dissolution attack was promoted by the interplay of certain steel microstructural features (grain boundaries, deformation twin laths, precipitates) with the dissolution corrosion process. The identified dissolution mechanisms were selective leaching leading to steel ferritization, and non-selective leaching; the latter was mainly observed in the solution-annealed steel. The maximum corrosion rate decreased with exposure time and was found to be inversely proportional to the depth of dissolution attack.

  11. Properties of hot rolled steels for enamelling

    International Nuclear Information System (INIS)

    Gavrilovski, Dragica; Gavrilovski, Milorad

    2003-01-01

    The results of an investigation of the structure and properties of experimental produced hot rolled steels suitable for enamelling are presented in the paper. Hot rolled steels for enamelling represent a special group of the steels for conventional enamelling. Their quality has to be adapted to the method and conditions of enamelling. Therefore, these steels should meet some specific requirements. In addition to usual investigation of the chemical composition and mechanical properties, microstructure and quality of the steel surface also were investigated. The basic aim was to examine steels capability for enamelling, i. e. steels resistance to the fish scales phenomena, by trial enamelling, as well as quality of the steel - enamel contact surface, to evaluate the binding. Also, the changes of the mechanical properties, especially the yield point, during thermal treatment, as a very specific requirement, were investigated, by simplified method. Good results were obtained confirming the steels capability for enamelling. (Original)

  12. Chromium Enrichment on P11 Ferritic Steel by Pack Cementation

    Directory of Open Access Journals (Sweden)

    Fauzi F. A.

    2016-01-01

    Full Text Available The future thermal power plant is expected to operate at higher temperature to improve its efficiency and to reduce greenhouse gas emission. This target requires better corrosion properties of ferritic steels, which commonly used as materials for superheater and reheater of boiler tubes. In this work, chromium enrichment on the surface of ferritic steel is studied. The deposited chromium is expected to become a reservoir for the formation of chromia protective layer. Chromium was deposited on the substrate of steel by pack cementation process for two hours at the temperature of 850ºC, 950ºC and 1050ºC, respectively. XRD analysis indicated that chromium was successfully deposited at all temperatures. Somehow, SEM cross sectional image showed that continuous layer of chromium was not continuously formed at 850oC. Therefore, this research clarify that chromium enrichment by pack cementation may be conducted at the temperature above 950°C.

  13. Martensitic transformation induced by irradiation and deformation in stainless steels

    International Nuclear Information System (INIS)

    Maksimkin, O.P.

    1997-01-01

    In the present work the peculiarities of martensite γ → α , (γ → ε → α , ) transformation in the steels with a low stacking fault energy (12Cr18Ni10T, Cr15AG14) irradiated by neutrons, α-particles and electrons (pulse and stationary) and then deformed with the various strain rates in the temperature range - 20 - 1000 C are considered. It is established by the electron-microscope research that the phase γ → α ' transition in irradiated and deformed steels is observed on the definite stage of evolution of the dislocation structure (after the cell formation) and the martensite formation preferentially occurs on a stacking fault aggregation. The regularities of the irradiation by high energy particles effect on the formation parameters and martensite α , -phase accumulation kinetics ones and also their role in forming of the strength and ductile properties in steels are analysed. (A.A.D.)

  14. Surface modification of steels by electrical discharge treatment in electrolyte

    International Nuclear Information System (INIS)

    Krastev, D.; Paunov, V.; Yordanov, B.; Lazarova, V.

    2013-01-01

    Full text: In this work are discussed some experimental data about the influence of applied electrical discharge treatment in electrolyte on the surface structure of steels. The electrical discharge treatment of steel surface in electrolyte gives a modified structure with specific combination of characteristics in result of nonequilibrium transformations. The modification goes by a high energy thermal process in a very small volume on the metallic surface involving melting, vaporisation, activation and alloying in electrical discharges, and after that cooling of this surface with high rate in the electrolyte. The surface layers obtain a different structure in comparison with the metal matrix and are with higher hardness, wear resistance and corrosion resistance. key words: surface modification, electrical discharge treatment in electrolyte, steels

  15. Study of 316 stainless steel swelling due to neutron irradiation

    International Nuclear Information System (INIS)

    Furutani, Gen; Konishi, Takao

    2000-01-01

    Large stresses will be generated in the austenitic stainless steel core internals of pressurized water reactors (PWRs) if excessive swelling occurs after long periods of operation. As a result, deformation or stress corrosion cracking (SCC) could occur in the core internals. However, data on the swelling of irradiated austenitic stainless steel in actual PWRs is limited. In this study, mechanical tests, measurement of produced helium amount and analysis using transmission electron microscopes were carried out on a cold-worked (CW) 316 stainless steel flux thimble tube irradiated up to approximately 35 dpa in a Japanese PWR. The swelling was evaluated to be approximately 0.02%. This level of swelling was much lower than the swelling of the more than several percent that has been observed in fast breeder reactors. (author)

  16. Adhesiveness of cold rolled steels for car body parts

    Directory of Open Access Journals (Sweden)

    Kleiner Marques Marra

    2007-09-01

    Full Text Available The aim of this work was to evaluate the adhesiveness of uncoated and zinc-electrogalvanized steel sheets used in the automotive industry. Three types of adhesives, one acrylic and two epoxy resins, were employed to join low carbon cold rolled steels, one uncoated and another electrogalvanized, both previously degreased or chemically pickled. Mechanical strength of the joints was evaluated by the T-peel and tensile strength tests. Steel grade, surface condition and heating below the cure temperatures did not influence the joints' mechanical strength. However, their shear strength decreased drastically as the test temperature increased. The exposure of the joints to an atmosphere with 90% relative humidity at 40 °C caused reduction of their shear strength. Epoxy adhesives showed higher mechanical strength, but exhibited higher degradation by humidity.

  17. Electron beam freeforming of stainless steel using solid wire feed

    International Nuclear Information System (INIS)

    Wanjara, P.; Brochu, M.; Jahazi, M.

    2007-01-01

    The use of electron beam technology for freeforming build-ups on 321 stainless steel substrates was investigated in this work by using 347 stainless steel as a filler metal. The electron beam freeforming studies indicated that line build-ups could be deposited on the substrate material for optimized processing conditions and a slight linear thickening of the re-build occurred as a function of the deposited layer. The evolution in the formation of the Ti (C, N) (Nb, Ti) carbonitrides and Nb (C, N) precipitates was demonstrated to counteract the formation of detrimental Cr-carbides usually observed during welding stainless steels. The mechanical properties of the re-build were similar to the properties of the base metal, showing that homogeneous properties can be expected in the repaired components

  18. Simulation of Thermo-viscoplastic Behaviors for AISI 4140 Steel

    Science.gov (United States)

    Li, Hong-Bin; Feng, Yun-Li

    2016-04-01

    The thermo-viscoplastic behaviors of AISI 4140 steel are investigated over wide ranges of strain rate and deformation temperature by isothermal compression tests. Based on the experimental results, a unified viscoplastic constitutive model is proposed to describe the hot compressive deformation behaviors of the studied steel. In order to reasonably evaluate the work hardening behaviors, a strain hardening material constant (h0) is expressed as a function of deformation temperature and strain rate in the proposed constitutive model. Also, the sensitivity of initial value of internal variable s to the deformation temperature is discussed. Furthermore, it is found that the initial value of internal variable s can be expressed as a linear function of deformation temperature. Comparisons between the measured and predicted results confirm that the proposed constitutive model can give an accurate and precise estimate of the inelastic stress-strain relationships for the studied high-strength steel.

  19. Testing new tribo-systems for sheet metal forming of advanced high strength steels and stainless steels

    DEFF Research Database (Denmark)

    Bay, Niels; Ceron, Ermanno

    2014-01-01

    of a methodology for off-line testing of new tribo-systems for advanced high strength steels and stainless steels. The methodology is presented and applied to an industrial case, where different tribo-systems are tested. A universal sheet tribotester has been developed, which can run automatically repetitive......Testing of new tribo-systems in sheet metal forming has become an important issue due to new legislation, which forces industry to replace current, hazardous lubricants. The present paper summarizes the work done in a recent PhD project at the Technical University of Denmark on the development...

  20. Microstructure and corrosion behavior of shielded metal arc-welded dissimilar joints comprising duplex stainless steel and low alloy steel

    Science.gov (United States)

    Srinivasan, P. Bala; Muthupandi, V.; Sivan, V.; Srinivasan, P. Bala; Dietzel, W.

    2006-12-01

    This work describes the results of an investigation on a dissimilar weld joint comprising a boiler-grade low alloy steel and duplex stainless steel (DSS). Welds produced by shielded metal arc-welding with two different electrodes (an austenitic and a duplex grade) were examined for their microstructural features and properties. The welds were found to have overmatching mechanical properties. Although the general corrosion resistance of the weld metals was good, their pitting resistance was found to be inferior when compared with the DSS base material.