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Sample records for steel-kh12m

  1. Peculiarities of welding procedure for the 05Kh12K14N5M5T-VD maraging stainless steel with strength higher 1500 MPa

    International Nuclear Information System (INIS)

    Pustovit, A.I.

    1980-01-01

    The effect of welding procedure of 05Kh12K14N5M5T-VD stainless steel on the properties of its welded joints is investigated. A new procedure of welding for pressure vessels made of this steel using Sv-03Kh15K14N5M3T-EL welding wire is suggested [ru

  2. Preliminary heat treatment of 4KhM2Fch die steel

    International Nuclear Information System (INIS)

    Leonidov, V.M.; Berezkin, Y.A.; Nikitenko, E.V.

    1986-01-01

    To improve the machinability and preparation of the structure for hardening, die steels are given a preliminary treatment which provides a reduction in hardness as a result of separation in the structure of the carbide and ferrite phases, coagulation of the carbides, and acquisition by them of a granular form and also the obtaining of fine grains and a uniform distribution of the structural constituents. The microstructure was evaluated after etching in 4% nital on an MIM-8M microscope. The 4KhM2Fch steel was given a preliminary heat treatment of normalize and anneal. It was concluded that for 4KhM2Fch steel a preliminary heat treatment of normalizing from 950 0 C with a hold of 1.5-2 h, annealing at 750-760 0 C with a hold of 2-3 h, cooling to the isothermal temperature of 670-680 0 C with a hold of 3-4 h, and further air cooling is recommended. The structure after such a heat is granular pearlite with a rating 1-2 and a hardness of 220-250 HB

  3. 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

  4. Pipes out of the chromium-molybdenum 12Kh2M1 steel intended for power units

    International Nuclear Information System (INIS)

    Saf'yanov, A.V.; Plyatskovskij, O.A.; Khokhlov-Nekrasov, O.G.; Palatnikova, E.S.; Karpenko, N.P.

    1977-01-01

    Vanadiumless steel 12Kh2M1 (2.25%Cr, 1%Mo) known to be applied abroad has been used for production of 325x60 mm tubes. The technology involves heating of the blanks to 1270-1300 deg C, their piercing in a double-roller mill, rolling on a pilger mill 8-16'' in thick wall caliber rolls, thermal treatment (normalizing at 930-960 deg C for 1 hour and tempering at 730+-10 deg C for 4 hours and etching (12-22% H 2 SO 4 and up to 143 g/l FeSO 4 ) for 3-4 hours at 55-65 deg C. Good technological properties of the steel and its capacity of working at 540-580 deg C are confirmed. Vanadium alloying of boiler steels does not provide for essential improvement of oxydation resistance and long term strength, but decreases the workability and enhances scatter of working parameters on account of minor variations of chemical composition

  5. Welding of high-strength stainless steel 03Kh12N10MT for cryogenic engineering

    International Nuclear Information System (INIS)

    Pustovit, A.I.

    1989-01-01

    Consideration is being given to weld resistance to cold and hot cracking at 93 and 77K and to mechanical properties of welded joints of high-strength stainless steel 03Kh12N10MT, produced under the fluxes AN-17M, AN-18, AN-26, AN-45, ANF-5, 48-OF-6, ANK-45 and ANK-49 in combination with various welding wires. It is shown that welds on 03Kh12N10MT steel meet the requirements only when using 48-OF-6 or ANK-49 flux. It is noted that impact strength of welds at 77K is sufficiently affected by the volume fraction of non-metallic inclusions in weld metal

  6. On the corrosion resistance of 01Kh25 ferritic steel

    International Nuclear Information System (INIS)

    Eremeeva, R.A.; Koval', E.K.

    1989-01-01

    Effect of non-ferrous metal ions on corrosion behaviour of 01Kh25 specific low carbon steel as compared to austenitic 12Kh18N10T and 06KhN28MDT steels in boiling solutions of sulfuric and nitric acids and their mixture is studied. Compositions initating commercial ones are chosen the media. It is shown that trough corrosion resistance of 01Kh25 steel in 10% H 2 SO 4 is two order below 06KhN28MDT austenitic steel in presence of Cu 2+ ions as a result of the surface passivation corrosion resistance of ferritic steel is an order higher the austenitic ones. Ferrite steel resistance in the nitric acid and its mixture with sulfuric acid is five timesas much as in 12Kh18N10T austenitic steel

  7. Effect of rolling temperature on 12Kh18N10T steel tube hardening

    International Nuclear Information System (INIS)

    Yushkevich, P.M.; Stepanovich, V.E.; Manankova, L.V.; Usenko, V.N.; Semenov, I.A.

    1984-01-01

    Mechanical properties and substructure of tubes at the constant reduction degree k(the ratio of deformation over wall thickness to deformation over diameter), depending on strain degree during cold and hot tube rolling, have been studied. The investigations are carried out using hot-rolled tubes with the dimensions 88x8 mm of 12Kh1hN10T steel. With the decrease of strain over the wall of the tube, produced of 12Kh18N10T steel as to strain over diameter the values of yield strength and ultimate strength increase with simultaneous decrease in ductility during warm rolling and yield strength and ultimate strength decrease with the increase in ductility-during cold rolling. During warm rolling of the tubes at 250 deg C the hardening of 12Kh18N10T steel is higher, than at the rolling temperature 150 deg C. The optimum temperature range of warm rolling is 120-150 deg C. Grain orientation in the metal of the tubes and degree of texture perfection increase with the temperature increase of the tube warm drolling as compared with col rolli

  8. Heat affected zone structure in welded joints of 15Kh1M1FL, 25Kh2NMFA and 20KhN2MFA steels

    International Nuclear Information System (INIS)

    Levenberg, N.E.; German, S.I.; Fomina, O.P.; Netesa, E.M.; Tsaryuk, A.K.; Kornienko, T.A.

    1983-01-01

    Heat affected zone (HAZ) structure of thick-walled, nature joints of 15Kh1M1FL steel for block structure of power reactors and 25Kh2NMFA and 20KhN2MFA steels for rotors - is investigated. Multi-layer arc welding is performed under conditions being created for standard components of turbines. Thermokinetics diagrams of austenite decomposition are built, phase composition and character of the structure forming at HAZ in the process of welding with preheating are studied. It is shown that at HAZ in joints of the steels under consideration in the process of welding with preheating is formed a structure of a grained bainite which is uniform in its structure and phase composition. Small volumes of round and elongated forms consisting of martensite and residual austenite are distributed in α-solid solution of the bainite. The bainite of the HAZ in welded joints possesses high hardness and great stability in the process of tempering

  9. Development of plastic deformations in 12Kh18N10T steel under cyclic symmetrical bending of specimens of various length

    Energy Technology Data Exchange (ETDEWEB)

    Pisarenko, G.S.; Leonets, V.A.; Bega, N.D. (AN Ukrainskoj SSR, Kiev. Inst. Problem Prochnosti)

    1983-08-01

    Effect of specimen length on intensity of plastic deformation development and cyclic strength is studied for annealed 12Kh18N10T steel under cyclic symmetrical bending. The intensity of microplastic deformations and cyclic strength of annealed 12Kh18N10T steel in the considered case is due to self-heating.

  10. Defect accumulation in welded joints of 12Kh1MF steel steam pipelines during creep

    International Nuclear Information System (INIS)

    Anokhov, A.E.; Alekhova, I.A.

    1982-01-01

    Technique for investigation of micropore accumulation in 12Kh1MF steel welded joints is proposed. The micropore density in different zones of welded joints in non-uniform. It is shown that failure localization in welded joint in the softening zone during the creep takes place due to the micropore priority accumulation in this zone. It is found out that accumulation of residual deformations in different zones of 12Kh1MF welded joints under creep runs more uniformly as the level of working stresses decreases and test duration increases

  11. Effect of the isothermal transformation temperature on the fine structure of steel-12Kh1MF

    International Nuclear Information System (INIS)

    Mints, I.I.; Berezina, T.G.; Lanskaya, K.A.

    1976-01-01

    For detailed analysis of bainite and pearlite in steel 12Kh1MF, homogeneous structures were obtained by isothermal annealing at 350, 450, 500, and 650 0 for 1 h. Isothermal transformation of austenite leads to the formation of bainite at 350-500 0 and pearlite at 650 0 . The austenitizing temperature was 980 0 for both types of samples, with holding for 20 min. For comparison, the plates were quenched from 980 0 and 1050 0 in ice-cold brine. The investigation was conducted with use of light and electron microscopes and x-ray analysis. The long-term strength was also determined. Isothermal treatment of steel 12Kh1MF at 350-500 0 C leads to the formation of a structure consisting of upper and lower bainite. At 500 0 the structure consists primarily of upper bainite, and at 350 0 of lower bainite. With tempering of the steel with a structure of upper and lower bainite at 730 0 for 3 h the dislocations undergo redistribution of the polygonization type within ferrite needles, with development of a cellular substructure. The acicular structure of the matrix is retained in this case. The density and evenness of the distribution of carbides is higher in upper bainite than in lower bainite. Steel 12Kh1MF with a structure of upper bainite is more susceptible to recrystallization as compared with a structure of lower bainite, which is responsible for the higher heat resistance of the latter

  12. Increasing the brittle fracture resistance in manual arc welding and heat treatment of type 12KhM steels

    International Nuclear Information System (INIS)

    Tikhonov, V.P.; Bychenkova, G.A.; Gordeev, Y.V.; Ilyuhov, C.V.

    1984-01-01

    The extensive application of heat-resisting steels is delayed by their poor weldability. Optimum technology has been developed for manual arc welding and heat treatment of structures of type 12KhM steels resulting in high cracking resistance. Trials were conducted to evaluate the efficiency of removing the structural stresses in tempering the structures. On the basis of the experimental results, it may be assumed that the toughness properties of the welded joints produced by manual arc welding can be improved by optimizing the alloying system of the weld metal, with the parent metal treated in the optimum heat treatment conditions. The aim of subsequent investigations was to assess the properties of the weld metal made with vanadium-free electrodes. It was found that the impact toughness increased two to three times; the mean hardness and the maximum hardness were both less than 220. The reduction in hardness and increase of the toughness properties of the metal are caused by the lower degree of hardening of the bulk of the grain and, consequently, by the lower concentration of plastic strain at the grain boundaries

  13. Experience manufacturing and properties of the high-strength corrosion-resistant magnetic 03Kh12K12D2 steel

    International Nuclear Information System (INIS)

    Fel'dgandler, Eh.G.; Moshkevich, E.I.; Bakuma, S.F.; Bulat, S.I.; Tikhonenko, V.D.

    1976-01-01

    In industrial conditions, steel 03Kh12K12D2 (DI48-VD) was melted in a 7-tinduction furnace with subsequent vacuum arc remelting. Ingots of dia 500 and 630 mm were forged into slabs and forgings. The slabs were rolled into sheets, 40 mm thick, and the forgings were rolled into sectional shapes. To obtain the optimum mechanical, corrosion, and magnetic properties, the metal was annealed at 600 deg C (10 hr) and 650 deg C (5 and 10 hr). The developed melting and remelting process enabled to obtain steel meeting all the requirements as for the chemical composition, workability, and mechanical magnetic properties. On testing in water with high parameters (200 deg C, 16 kgf/cm 2 ) and in synthetic sea water (70-90 deg C) the corrosion rate did not exceed 1 μm per year

  14. Corrosion resistance of welded joints in 08Kh22N6T and 08Kh21N6M2T steels made with new electrodes

    International Nuclear Information System (INIS)

    Sidorkina, Y.S.; Leibzon, V.M.; Mankevich, T.V.; Sidlin, E.A.; Zheltova, G.A.

    1986-01-01

    This paper examines the corrosion resistance of 08Kh22N6T and 08Kh21N6M2T steels which would make it possible to ensure equal properties of all the zones of the welded joints. The investigations were carried out on the welded joints in the steels produced with new OZL-40 and OZL-41 electrodes and with standard TsL-11 and EA-400/10u electrodes. The chemical compositions of the steels and deposited metal are presented. The tests of the intercrystalline corrosion resistances of the welded joints in the steels in the as-welded condition and after heat treatment showed that the weld metal is not attacked by intercrystalline corrosion. The tests also showed that the welded joints in 08Kh22N6T steel made with the OZL-40 and TsL-11 electrodes are resistant to corrosion in 55% phosphoric acid at 90 C in 1% sulfuric acid, and in 25% formic acid at 80 C. The investigated steels made with the OZL-40 and OZL-41 electrode respectively show that the welded joints are resistant to intercrystalline and general corrosion, have high mechanical and processing properties and the electrodes, and can be used for welding equipment designed for service in alkaline, neutral, and slightly acid media

  15. Hardening and stress relaxation during repeated heating of 15Kh2MFA and 15Kh2NMFA steels welded joints

    International Nuclear Information System (INIS)

    Zubchenko, A.S.; Suslova, E.A.

    1986-01-01

    Results of investigation of temperature-time conditions of hardening of welded joints of 15Kh2MFA and 15Kh2NMFA steels and their relaxation resistance, effect of metal structure of imitated heat affected zone (HAZ) on intensity of precipitation hardening at repeated heating are presented as well as the results of the process of relaxation of residual stresses at welded joints samples heating carried out by automatic welding under the flux with the use of adding materials and technology of manufacturing of vessels of WWER-440 and WWER-1000 reactors. Peculiarities of the hardening at repeated heating of the HAZ metal imitated at these steels. Precipitation hardening of overheated 15Kh2MFA steel is connected with precipitations at repeated heating of carbides of the M 7 C 3 , M 3 C and VC type. Stress relaxation in welded joints runs more intensively at the initial stage of repeated heating, i.e. during the same period of the process of dispersed carbide precipitations

  16. Effect of melting technique on grain size and heat resistance of the 12Kh1MF steel

    International Nuclear Information System (INIS)

    Lanskaya, K.A.; Kulikova, L.V.; Butneva, N.I.

    1978-01-01

    Investigated are the 12Kh1MF steel melted in open-hearth and arc furnaces (deoxidation by aluminium in 1.0 kg/t quantity) and then subjected to electroslag melting. The size of an austenitic grain depends on the residual contents of nitrogen and aluminium in steel. The open-hearth metal subjected to electroslag melting and containing a small quantity of nitrogen (0.006%) and aluminium (0.013%) has coarse austenitic grains and higher heat resistance compared to the steel melted in an arc furnace and also sub ected to electroslag melting. The nitride analysis of steel is carried out

  17. Investigation of 12Kh1MF steel resistance to brittle fractures

    International Nuclear Information System (INIS)

    Bologov, G.A.; Rushchits, T.Yu.

    1977-01-01

    The metal of hot-rolled steam pipe made of 12Kh1MF steel, which has been subjected to thermal treatment under laboratory conditions, and metal samples from acting steam pipes after different exploitation periods at 510-565 deg C have been investigated. The dependence of impact viscosity and its constituents on conditions of thermal treatment has been established. The energy consumed by the developing crack has been used as an impact viscosity criterion. Appropriate thermal treatment is capable of rehabilitating the impact viscosity of embrittled metal. Cold plastic deformation increases crack propagation rate in the initial metal and promotes embrittlement during exploitation. Ageing of the working metal reduces its capacity of stopping the developing crack and shifts the temperature threshold of brittleness towards positive temperature

  18. Mechanical properties and kinetics of bainite transformation in the 35KhN3MFA and 25KhN3MFA steels

    International Nuclear Information System (INIS)

    Korotushenko, G.V.; Grigorkin, V.I.; Kozlov, V.I.; Sandomirskij, M.M.; Krivonosova, L.F.

    1978-01-01

    The mechanical properties and phase composition of the 25KhN3M A and 25KhN3M A bainitic steels have been investigated under austenization temperature varying from 870 to 1180 deg C and quenching cooling rate varying from 1 to 18x10 3 deg/min. Roentgen and quantitative phase analyses were employed. When bainitic steels are subjected to quenching by cooling with slow rate, their structure reveals b.c.c.-bainite with carbon content below the steel average, tetragonal martensite with a higher carbon content, carbon-rich residual austenite and carbides. Decreasing quenching cooling rates increase the concentration of tetragonal martensite and residual austenite and correspondingly reduce the concentration of b.c.c.-bainite. This tends to degrade the structural strength of bainitic steels in cores of large-size forged products

  19. Nitrogen-containing superlow-carbon austenitic steel 02Kh25N22AM2

    Science.gov (United States)

    Fe'ldgandler, É. G.; Svistunova, T. V.; Savkina, L. Ya.; Lapshina, O. B.

    1996-02-01

    At present the equipment for manufacturing carbamide mineral fertilizers is produced from domestic steel 03Kh17N14M3 having "carbamide quality." Imported equipment also used in the industry is produced from steel of the 25-22-2 (Cr -Ni-Mo) type shipped by various firms, namely, 2RE69 (Sandvik, Sweden), 254SFER (Avesta, Sweden), 2522LCN (VDM, Germany), DM 1.4466 (Germany), and X2CrNiMo 25-22-2 (Dalmine, Italy). The imported steels are used because in some units steel 03Khl7Nl4M3 does not provide the requisite corrosion resistance in an intensified process of carbamide manufacturing. We currently possess domestic high-alloyed steel for producing new and repairing imported equipment operating under the severe conditions of carbamide synthesis. The present paper concerns the structure, mechanical properties, and corrosion resistance of industrially produced steel 02Kh25N22AM2 (ChS-108) and the recommended range of its application.

  20. Metallographical procedure for detecting carburized layer in the 12Kh18N10T steel tubes

    International Nuclear Information System (INIS)

    Najmark, S.I.; Shmalenyuk, R.P.

    1977-01-01

    The various causes of the tendency to intercrystalline corrosion of stainless steel tubing were studied. 12Kh18N10T steel tube specimens were metallographically investigated to reveal the presence and depth of the carburized layer. Unlubricated specimens and specimens with the graphite-saltpeter lubrication applied on them were austenized in the temperature range from 950 to 1250 deg C and then exposed to a provoking anneal at 650 deg C for 24 h. All the lubricated specimens showed a carbide network along grain boundaries and intercrystalline cracks. The specimens treated without lubrication had no cracks. The method offered can differentiate poor tube cleaning and the undesirable effect of other processing steps on the tubes

  1. Heat treatment effect on impact strength of 40Kh steel

    International Nuclear Information System (INIS)

    Golubev, V.K.; Novikov, S.A.; Sobolev, Yu.S.; Yukina, N.A.

    1984-01-01

    The paper presents results of studies on the effect of heat treatment on strength and pattern of 40Kh steel impact failure. Loading levels corresponding to macroscopic spalling microdamage initiation in the material are determined for three initial states. Metallographic study on the spalling failure pattern for 40Kh steel in different initial states and data on microhardness measurement are presented

  2. Effect of zirconium on the structure and phase composition of steel 03Kh8SYu

    International Nuclear Information System (INIS)

    Tarzhumanova, V.A.; Ryabchenkov, A.V.; Shatunova, A.V.; Yoganova, S.A.

    1986-01-01

    Previously, the authors determined the optimum zirconium content providing retention of a fine-grained structure for steel 03Kh8SYu during high-temperature heating. It was suggested that this was caused by separation in the steel of intermetallic phase Fe 3 Zr. This paper presents results of further studies in this direction. X-ray analysis results for the anodic residues of the steels are presented. It can be seen that in steel without zirconium, carbides of the type M 23 C 6 and M 7 C 3 and aluminum nitride are present. On adding 0.05% Zr, zirconium nitride forms in addition to the existing aluminum nitride and carbides of the type M 7 C 3 . The authors also investigated the effect of zirconium on the tendency of the steel toward grain growth at higher temperature; they studied the structure of steel 03Kh8SYu with 0.61% Zr after soaking specimens for 100 h at 950-1100 C. Results are presented

  3. Simulation of Microdamage and Evaluation of Remaining Life of Steam Conduit Components from New-Generation Refractory Steel 10Kh9MF-Sh

    Science.gov (United States)

    Gladshtein, V. I.

    2018-03-01

    The effects of microdamage on the remaining life of high-temperature components of steam conduits from high-chromium steel 10Kh9MF-Sh and low-alloy steel 12Kh1M1F are compared. To simulate the microdamage, specimens with a circular notch and different relative diameters are fabricated. Specimens with a notch simulating the highest degree of microdamage and smooth specimens are tested for long-term strength. The coefficient of the remaining life of a conduit is computed for the range of relative damage presenting practical interest.

  4. 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

  5. Features of argon-arc welding of aluminium alloy AD1 to stainless steel 12Kh18N10T

    International Nuclear Information System (INIS)

    Sadov, I.I.

    1982-01-01

    Welding of pipes made of the 12Kh18N10T stainless steel and the AD1 aluminium alloy is proposed to perform using one-sided aluminizing. It is recommended to use shields in order to protect internal and external surfaces of pipes, aluminizing of which is impossible. It is shown that developed technological process for welded joints made of aluminium and stainless steel for cryogenic apparatus permits to create light-duty cryostat assembly using aluminium alloys instead of copper alloys, to increase reliability of apparatus (usage of welded joints instead of soldered ones), and to improve labour conditions

  6. Effect of agressive medium movement of local corrosion of the steel - 12Kh18N10T

    International Nuclear Information System (INIS)

    Makartsev, V.V.; Pakhomov, V.S.; Abramova, I.M.

    1980-01-01

    The effect of agressive medium movement on the formation of pitting corrosion of the 12Kh18N10T stainless steel in the acidic chloride-nitrate solution at room temperature is studied. It is established that the agressive medium movement hinders the formation of pitting corrosion at potentials more negative than +0.4 V and practically does not affect it at more positive potentials. The investigations have been carried out on a disc electrode rotating at a speed from 0 to 2000 rot./min

  7. Additional materials for welding of the EP99 heat resisting alloy with the EI868 alloy and 12Kh18N9T steel

    International Nuclear Information System (INIS)

    Sorokin, L.I.; Filippova, S.P.; Petrova, L.A.

    1978-01-01

    Presented are the results of the studies aimed at selecting an additive material for argon-arc welding process involving heat-resistant nickel EP99 alloy to be welded to the EI868 alloy and 12Kh18N9T steel. As the additive material use was made of wire made of nickel-chromium alloys and covered electrodes made of the EP367 alloy with additions of tungsten. It has been established that in order to improve the resistance of metal to hot-crack formation during argon arc welding of the EP99 alloy with the EI868 alloy, it is advisable to use an additive material of the EP533 alloy, and while welding the same alloy with the 12Kh18N9T steel, filler wire of the EP367 alloy is recommended

  8. The effect of thermal treatment on corrosion properties of 0Kh15N16M3B stainless steel tested in the N2O4 boiling medium

    International Nuclear Information System (INIS)

    Kamenev, A.Ya.; Kopets, Z.V.; Mel'nikova, N.N.; Dergaj, A.M.; Fedyushin, E.E.

    1985-01-01

    The experimental data on the effect of thermal treatment on corrosion properties of stainless steel 00Kh16n15m3b tested in the N 2 O 4 boiling medium at 8.0 MPa and 433 K are presented. The electron microscope data on steel microstructure after different heat treatments and phase composition of oxide films emerging at corrosion test are given. It is shown, that the rise of the heat treatment temperature from 823 up to 1023 K increases total corrosion of 00Kh16n15m3b steel under given test conditions and practically does't affect intercrystalline corrosion. Developed oxide layers are of deposited nature and doesn't affect markedly the rate of progress of the corrosive processes. Taking into account high chromium volatility in vacuum one can assume that at the initial stages of the coolant effect, the process of depletion of steel surface by chromium durng heat treatment affects markedly steel corrosion stability

  9. Successive carbon- and boron saturation of KhVG steel in powder mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Alimov, Yu A; Gordienko, S I

    1975-01-01

    Method of successive saturation of KhVG steel with carbon and boron in powder mixtures is described. After carbonization of steel in a charcoal carburator at 930 deg C during 3 hrs a domain of equiaxial large grains is formed there the latter representing carbides of Fe/sub 3/C and (Fe, M)/sub 3/C. The increase of duration of carbonization up to 5 hrs and above results in formation of a cement grid greatly impairing the mechanical properties of the metal. Carbonization is followed by borating in powdered technical boron carbide at 900 deg C for 4 hrs which ensures formation on the sample surface of a borated layer with depth up to 65 mkm covering the carbonized zone. As followed from metallographic and x-ray structural analysis, the borated layer consists of boride needles with complex composition (Fe, Cr, Mn)B. Oil hardening of carbonized KhVG steel from 850 deg C and low-temperature tempering at 180 deg C for 1 hr results in formation in the main metal of martensite-carbide structure and, respectively, in the decrease of the microhardness gradient between the diffusion layers, as compared with borated KhVG steel. Operation tests of strengthened matrices of preforming machines under the conditions of application of dynamic pressing forces up to 1500 kg Fce/cm/sup 2/ demonstrated that the cyclical strength of carboborated coverings is 2.0-3.0 times higher than that of borated ones. The method of carboborating is recommended for strengthening the details of stamp and press tools.

  10. Structure, mechanical and corrosion properties of powdered stainless steel Kh13

    International Nuclear Information System (INIS)

    Radomysel'skij, I.D.; Napara-Volgina, S.G.; Orlova, L.N.; Apininskaya, L.M.

    1982-01-01

    Structure, mechanical and corrosion properties are studied for compact powdered stainless steel, Grade Kh13, produced from prealloyed powder and a mixture of chromium and iron powders by hot vacuum pressing (HVP) following four schemes: HVP of unsintered billets; HVP of presintered billets; HVP of unsintered billets followed by diffusion annealing; HVP of sintered billets followed by diffusion annealing. Analysis of the structure, mechanical and corrosion properties of Kh13 steel produced according to the four schemes confirmed that production of this steel by the HVP method without presintering of porous billets and diffusion annealing of compact stampings is possible only when prealloyed powder of particular composition is used as a starting material

  11. Effect of metal properties of casts of steel-15Kh1M1FL on the crack resistance at 565 deg C

    International Nuclear Information System (INIS)

    Gladshtejn, V.I.; Sheshenev, M.F.

    1976-01-01

    Results are given of prolonged tests of the metal of industrial casts with various fluidity limits. It has been shown experimentally that a quite satisfactory crack resistance is characteristic of a metal with a fluidity limit in the range 30-50 kgf/mm 2 . Metallographic studies have been conducted. Upon variation of the structure and properties of the 15Kh1M1FL steel during operation, the rate of growth of small cracks (up to 2.0 mm) decreases almost by 3 orders of ten (from 1.4x10 -4 to 2.0x10 -7 mm/hour). Subsequent structural changes during prolonged operation (over 50000 hours) result in a gradual increase in the rate of crack growth. At the same time resistance towards appearance of the impermissible high rate of the crack growth, Ksub(10sup(-3)), diminishes monotonically with the operation time. The metal of industrial 15Kh1M1FL steel casts has good crack resistance (Ksub(10sup(-3)) =30-70 kgf/mmsup(3/2) and Vsub(ef) =) kgf/mm 2 ) and a satisfactory local plasticity (critical opening being no more than 0.20 mm for 10 3 hours)

  12. Reliability and durability of the 12Kh1MF steel tubes of electroslag remelting and their welded joints

    International Nuclear Information System (INIS)

    Lanskaya, K.A.; Kulikova, L.V.; Mazel', R.E.; Khromchenko, F.A.; Strizhenova, V.F.

    1978-01-01

    Results of investigating the positive effect of electrolag remelting (ESR) on the properties of the base metal and welded joint of the 12Kh1MF steel steam pipes with the aim of increasing their durability up to 20,000 hrs, are presented. To estimate the quality and properties of tube billet metal, microstructure, content and nature of nonmetallic inclusions, content of gases, austenite grain size, austenite transformations during continuous cooling, metal ductility, mechanical properties at different temperatures and heat resisting properties, have been investigated. It is established, that the base metal in tubes of electroslag remelting possess higher heat resistance, while welded joints besides, have high deformability and resistance to brittle fracture

  13. 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

  14. Structural changes in complex steels with 12 % Cr during welding thermal cycle

    International Nuclear Information System (INIS)

    Ul'yanova, N.V.; Kurnosova, N.D.

    1981-01-01

    The structural changes in the heat affected zones of welded steam tubes of the 12Kh11V2MF and 18Kh12VMBFR steels, are investigated. A short-time heating of thin samples up to 1300-900 deg C with the aim of imitating the thermal welding cycle permits to determine temperatures of specific region formation in heat affeced zones of 12% Cr steels. The difference in the amounts and structure of σ-ferrite and γ-phase in these regions is established. A ''tongue'' nature of γ-phase grain growth is found in the temperature range of 1150-1100 deg C, while at 1300-1250 deg C σ-ferrite growth with the formation of saw-shape boundaries is observed. It is shown that tensile properties of imitated heat affected zone of 12Kh12VMBFP steel increase with heating temperature with the insignificant plasticity decrease. Impact strength on longitudinal samples decreases but remains higher than that determined by specifications [ru

  15. The Kinetics of Bainitic Transformation of Roll Steel 75Kh3MF

    Science.gov (United States)

    Kletsova, O. A.; Krylova, S. E.; Priymak, E. Yu.; Gryzunov, V. I.; Kamantsev, S. V.

    2018-01-01

    The critical points of steel 75Kh3MF and the temperature of the start of martensitic transformation are determined by a dilatometric method. The thermokinetic and isothermal diagrams of decomposition of supercooled austenite are plotted. The microstructure and microhardness of steel specimens cooled at different rates are studied. The kinetics of the occurrence of bainitic transformation in the steel is calculated using the Austin-Ricket equation.

  16. Effect of Cr, Ni, and Mo additions on the susceptibility of the 0Kh6n7m7c steel to hot cracking

    International Nuclear Information System (INIS)

    Tolstykh, L.G.; Pryakhin, A.V.; Popov, A.N.; Usynin, V.F.

    1977-01-01

    The effect of chromium, molybdenum, and nickel on the tendency of surfacing materials to form hot cracks (Vsub(kp) was studied using the mathematical statistics method. The St3 steel and 38KhN3MFA steel were used in the study. A device facilitating the hot cracking tendency test procedure was developed. It was found that, in the concentration range involved, Ni and Mo produce no effect on Vsub(kp), and Cr enhances it. A new powder wire, PP-OKh7N8M6S, capable of increasing surface material resistance by 1.5-2 times, has been developed

  17. 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

  18. Evolution of secondary-phase precipitates during annealing of the 12Kh18N9T steel irradiated with neutrons to a dose of 5 DPA

    Science.gov (United States)

    Tsai, K. V.; Maksimkin, O. P.; Turubarova, L. G.

    2007-03-01

    The formation and evolution of thermally-induced secondary precipitates in an austenitic stainless steel 12Kh18N9T irradiated in the core of a laboratory reactor VVR-K to a dose of 5 dpa and subjected to post-radiation isochronous annealings for 1 h in a temperature range from 450 to 1050°C have been studied using transmission electron microscopy (TEM) and microhardness measurements. It has been shown that the formation of stitch (secondary) titanium carbides and M 23C6 carbides at grain and twin boundaries after annealing at 1050°C is preceded by a complex evolution of fineparticles of secondary phases (titanium carbides and nitrides) precipitated at dislocation loops and dislocations during annealing at temperatures above 750°C.

  19. Effect of hot rolling on the structure and the mechanical properties of nitrogen-bearing austenitic-martensitic 14Kh15AN4M steel

    Science.gov (United States)

    Bannykh, O. A.; Betsofen, S. Ya.; Lukin, E. I.; Blinov, V. M.; Voznesenskaya, N. M.; Tonysheva, O. A.; Blinov, E. V.

    2016-04-01

    The effect of the rolling temperature and strain on the structure and the properties of corrosionresistant austenitic-martensitic 14Kh15AN4M steel is studied. The steel is shown to exhibit high ductility: upon rolling in the temperature range 700-1100°C at a reduction per pass up to 80%, wedge steel specimens are uniformly deformed along and across the rolling direction without cracking and other surface defects. Subsequent cold treatment and low-temperature tempering ensure a high hardness of the steel (50-56 HRC). Austenite mainly contributes to the hardening upon rolling in the temperature range 700-800°C at a reduction of 50-70%, and martensite makes the main contribution at higher temperatures and lower strains. Texture does not form under the chosen deformation conditions, which indicates dynamic recrystallization with the nucleation and growth of grains having no preferential orientation.

  20. Rupture of the steel-12KH1MF under creep at temperatures close to 0,5 Tsub(melt)

    International Nuclear Information System (INIS)

    Berezina, T.G.; Ashikhmina, L.A.; Karasev, V.V.

    1976-01-01

    Optical and transmission microscopy and fractography techniques have been employed in studying the peculiarities of nucleation and growth of micropores in steel 12Kh1MF at creep. The nucleation of micropores occurs at the initial stages of creep at stress concentration points, predominantly following the retarded shear mechanism. Micropores grow by the way of diffusion, as well as following the deslocation mechanism. An important role in the process of micropore growth is played by pore opening through grain-boundary slip. Pores of 1 to 5 microns in size can be formed along grain boundaries both due to the growth of individual micropores and by coalescence of micropores at points of their concentration. Transition of the creep to the critical phase coincides with the process of the pores blending together to

  1. The effect of laser treatment on the wear resistance of steel in corrosive media

    International Nuclear Information System (INIS)

    Plyatsko, G.V.; Porter, A.I.; Prejs, G.A.; Mojsa, M.I.

    1975-01-01

    The corrosion mechanical wearing properties of steel 45 treated with a laser beam (H 100 =7800 Mn/sq.m) under friction with nitrated steel 40KhNMA (HV=7000 Mn/sq.m), chrome cast iron Kh15M (hardened and low-temperature tempered, modified), perlite cast iron and bronze are studied. The aqueous buffers with pH=6 and 11 are used as a corrosion active media. In a weakly acid medium the most intensive wearing of steel 40KhNMA is observed at P=8 Mn/sq.m. Its wearing reduces due to increase of pressure to 12 Mn/sq.m. Extent of steel 45 wearing increases with pressure increase from 8 to 12 Mn/sg.m. Friction coefficient of this pair changes by jumps at an increase of normal pressure and its variation range is smaller than that observed in an alkaline medium. The maximum value of friction coefficient is shifted to the higher pressure. The wearing of cast iron Kh15M-steel 45 pair has an alternative pattern. In an alkaline medium the cast iron wearing intensity shows a linear increase with the normal contact pressure but that of the steel changes jumpwise attaining extreme at 8 and 12 Mn/sq.m. In a weak acid medium the intensity of grasping and graphitization at the friction surface of cast iron Kh15M-steel 45 pair is higher than that in the alkaline medium. Experiments demonstrate an effectiveness of the laser beam treatment of steel 45 for its friction in the alkaline medium with nitrated steel 40KhNMA and with hardened low-temperature tempered cast iron 45 under friction contact pressure as high as 8 Mn/sq.m, and in acid medium at 12 and 8 Mn/sq.m respectively. The laser treatment provides high corrosion-mechanical stability of steel 45 and the counterbodies described, as well as the low friction coefficient of these pairs

  2. Influence of sulphur and phosphorus impurities on ductility of 25Kh2NMFA steel during forging

    International Nuclear Information System (INIS)

    Onishchenko, A.K.

    1989-01-01

    Using cylindrical samples of the 25Kh2NMFA steel with sulfur and phosphorus content in the range of 0.001-0.030%, tensile test with the rate of deformation 10 -3 s -1 at the temperatures of 800-1200 deg C has been conducted. Analysis of fracture foci and plasticity diagrams has shown, that to ensure ductility during forging and high mechanical properties, the content of sulfur and phosphorus impurities in the 25Kh2NMFA steel must not exceed 0.015%

  3. Welding procedure for 06Kh13N7D2 steel

    International Nuclear Information System (INIS)

    Muromtsev, B.I.; Turkov, I.I.

    1990-01-01

    Based on the results of investigations into the process strength, mechanical and corrosion properties of 08Kh13N7D2 steel welded joints, the optimal method of its welding and a possibility of applying it for high-strength mounting in nuclear power plants are determined

  4. Hydrogen effect on mechanical properties and flake formation in the 10KhSND steel rolled plates

    Energy Technology Data Exchange (ETDEWEB)

    Muradova, R G; Zakharov, V A; Kuzin, A P; Gol' tsov, V A; Podgajskij, M S [Donetskij Politekhnicheskij Inst. (Ukrainian SSR); Donetskij Nauchno-Issledovatel' skij Inst. Chernoj Metallurgii (Ukrainian SSR))

    1982-01-01

    The effect of hydrogen on mechanical properties of the 10KhSND steel rolled plates during natural aging is studied. Optimum period of metal acceptance tests, which are advisable to conduct after 5-7 day natural aging of finished products, are found out. The technique is worked out and a safe hydrogen content to prevent flake formation in the 10KhSND steel is determined. It is shown that a safe hydrogen content is dependent on the experiment conditions (sample dimensions, conditions of cooling, and prehistory).

  5. Hydrogen effect on mechanical properties and flake formation in the 10KhSND steel rolled plates

    International Nuclear Information System (INIS)

    Muradova, R.G.; Zakharov, V.A.; Kuzin, A.P.; Gol'tsov, V.A.; Podgajskij, M.S.

    1982-01-01

    The effect of hydrogen on mechanical properties of the 10KhSND steel rolled plates during natural aging is studied. Optimum period of metal acceptance tests, which are advisable to conduct after 5-7 day natural aging of finished products, are found out. The technique is worked out and a safe hydrogen content to prevent flake formation in the 10KhSND steel is determined. It is shown that a safe hydrogen content is dependent on the experiment conditions (sample dimensions, conditions of cooling, and prehistory)

  6. Protective effect of KhOSP-10 inhibitor during corrosion, hydrogenadsorption and corrosion cracking of a steel in sulfuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Mindyuk, A K; Svist, E I; Savitskaya, O P; Goyan, E B; Gopanenko, A N [AN Ukrainskoj SSR, Lvov. Fiziko-Mekhanicheskij Inst.

    1975-01-01

    The protective propeties of inhibitor KhOSP-10 in the time of corrosion and corrosive cracking of steel 40Kh are higher then those of inhibitors KPI-1, KI-1, I-I-V etc. Its ability to reduce steel hydrogenation is the same as in the case of KPI-1 inhibitor i.e. below that of KI-1. HCl additives enhance the efficiency of inhibitors KPI-1, KI-1, I-1-V etc. up to the protective ability of KhOSP-10. Kinetics of the electrode processes was estimated from polarization curves.

  7. Cooling rate and microstructure of surface layers of 5KhNM steel, machined by electroerosion method

    International Nuclear Information System (INIS)

    Foteev, N.K.; Ploshkin, V.V.; Lyakishev, V.A.; Shirokov, S.V.

    1982-01-01

    The cooling rate and microstructure of surface layers of steel 5KhNM machined by electroerosion method have been studied. It is shown that the difference in heating rate of the surface layers with electric discharge over the 5KhNM steel samples depth results in the intensive size reduction of the microstructure. In the surface layer alongside with martensite residual austenite is present, the lattice period of which increases with the increase of pulse duration, carbide phase of complex composition appears, and concentrational heterogeneity in alloying elements (except carbon) is absent

  8. Cooling rate and microstructure of surface layers of 5KhNM steel, machined by electroerosion method

    Energy Technology Data Exchange (ETDEWEB)

    Foteev, N.K.; Ploshkin, V.V.; Lyakishev, V.A.; Shirokov, S.V.

    1982-01-01

    The cooling rate and microstructure of surface layers of steel 5KhNM machined by electroerosion method have been studied. It is shown that the difference in heating rate of the surface layers with electric discharge over the 5KhNM steel samples depth results in the intensive size reduction of the microstructure. In the surface layer alongside with martensite residual austenite is present, the lattice period of which increases with the increase of pulse duration, carbide phase of complex composition appears, and concentrational heterogeneity in alloying elements (except carbon) is absent.

  9. Corrosion of austenitic steels and their components in vanadium-containing chloride melts

    Science.gov (United States)

    Abramov, A. V.; Polovov, I. B.; Rebrin, O. I.; Lisienko, D. G.

    2014-08-01

    The corrosion of austenitic 12Kh18N10T, 10Kh17N13M2T, and 03Kh17N14M3 steels and their components (Cr, Fe, Ni, Mo) in NaCl-KCl-VCl2 melts with 5 wt % V at 750°C is studied. The rates and mechanisms of corrosion of the materials under these conditions are determined. The processes that occur during contact of the metals and steels with vanadium-containing chloride electrolytes are investigated.

  10. Ultrasound surface treatment of Kh18N10T steel with different structural state. Ul'trazvukovaya poverkhnostnaya obrabotka stali Kh18N10T s razlichnym strukturnym sostoyaniem

    Energy Technology Data Exchange (ETDEWEB)

    Aksenov, V K; Danilov, P A; Mats, A V; Netesov, V M; Yaes, A A [AN Ukrainskoj SSR, Kharkov (Ukrainian SSR). Fiziko-Tekhnicheskij Inst.

    1989-09-01

    Ultrasound surface treatment (USST) is studied for its effect on the structure and mechanical-and-physical properties of Kh18N10T steel with different prehistory. It is shown that surface treatment may both increase and decrease steel microhardness.

  11. On the protective effect of KhOSP-10 inhibitor during corrosion, hydrogenadsorption and corrosion cracking of a steel in sulfuric acid

    International Nuclear Information System (INIS)

    Mindyuk, A.K.; Svist, E.I.; Savitskaya, O.P.; Goyan, E.B.; Gopanenko, A.N.

    1975-01-01

    The protective propeties of inhibitor KhOSP-10 in the time of corrosion and corrosive cracking of steel 40Kh are higher then those of inhibitors KPI-1, KI-1, I-I-V etc. Its ability to reduce steel hydrogenation is the same as in the case of KPI-1 inhibitor i.e. below that of KI-1. HCl additives enhance the efficiency of inhibitors KPI-1, KI-1, I-1-V etc. up to the protective ability of KhOSP-10. Kinetics of the electrode processes was estimated from polarization curves

  12. Influence of local microplastic strains on stress corrosion of 08Kh18N10T steel

    International Nuclear Information System (INIS)

    Moskvin, L.N.; Efimov, A.A.; Sherman, Ya.I.; Fedorova, T.I.

    1987-01-01

    Study on specific features of microhomogeneous strain in the process of plastic strain development and their role in stress corrosion of 08Kh18N10T steel sheet specimens subject to preliminary strain by 1, 3, 6, 16 and 23% and subsequent tests of stress corrosion in magnesium chloride solution at 150 deg C 140 MPa has been carried out. Analysis of test results has shown that microplastic strain is distributed over a specimen nonuniformly and is accompanied with the slip bands formation which are sources of corrosion crack origination and development. 08Kh18N10T steel manifests the highest trend to stress corrosion under 1% microplastic strain

  13. Long-term strength and allowable stresses of grade 10Kh9MFB and X10CrMoVNb9-1 (T91/P91) chromium heat-resistant steels

    Science.gov (United States)

    Skorobogatykh, V. N.; Danyushevskiy, I. A.; Schenkova, I. A.; Prudnikov, D. A.

    2015-04-01

    Currently, grade X10CrMoVNb9-1 (T91, P91) and 10Kh9MFB (10Kh9MFB-Sh) chromium steels are widely applied in equipment manufacturing for thermal power plants in Russia and abroad. Compilation and comparison of tensile, impact, and long-term strength tests results accumulated for many years of investigations of foreign grade X10CrMoVNb9-1, T91, P91, and domestic grade 10Kh9MFB (10Kh9MFB-Sh) steels is carried out. The property identity of metals investigated is established. High strength and plastic properties of steels, from which pipes and other products are made, for operation under creep conditions are confirmed. Design characteristics of long-term strength on the basis of tests with more than one million of hour-samples are determined ( and at temperatures of 500-650°C). The table of recommended allowable stresses for grade 10Kh9MFB, 10Kh9MFB-SH, X10CrMoVNb9-1, T91, and P91 steels is developed. The long-time properties of pipe welded joints of grade 10Kh9MFB+10Kh9MFB, 10Kh9MFB-Sh+10Kh9MFB-Sh, X10CrMoVNb9-1+X10CrMoVNb9-1, P91+P91, T91+T91, 10Kh9MFB (10Kh9MFB-Sh)+X10CrMoVNb9-1(T/P91) steels is researched. The welded joint reduction factor is experimentally determined.

  14. Influence of structure and properties of tubular billets of the 12 Kh 18N10T steel on deformability of tubes at cold-rolling mills

    International Nuclear Information System (INIS)

    Vil'yams, O.S.; Bol'shova, N.M.; Olejnik, O.V.; Velikotnaya, E.S.

    1979-01-01

    Metallographic analysis of the defects of the ''oblique cracks'' type on the surface of hot-rolled tubes of the 12Kh18N10T steel has been carried out. Recommended is the complex of mechanical properties and the structure factors (grain size) of conversion hot-rolled tubes, providing the combination of ductility and high rapture strength during rolling at pilger mills. At a grain size not coarser than number 5, a billet must have σsub(T) 5 >=40 %. Hot-rolled coarse-grained billet is not recommended for warm rolng because of high strain hardening

  15. Corrosion behavior of austenitic steels and their components in niobium-containing chloride melts

    Science.gov (United States)

    Abramov, A. V.; Polovov, I. B.; Rebrin, O. I.; Volkovich, V. A.; Lisienko, D. G.

    2014-02-01

    The mechanism of corrosion of austenitic steels 12Kh18N10T, 10Kh17N13M2T, and 03Kh17N14M3 and metals Cr, Fe, Ni, and Mo in a NaCl-KCl-NbCl n ( n = 3.5, Nb content is 5 ± 0.1 wt %) melt at 750°C is studied. The metal and steel corrosion rates under these conditions are determined. The character of material fracture and the mechanisms of material corrosion are found.

  16. Quality of austenite chrome-nickel steel made by gas-oxygen refining

    International Nuclear Information System (INIS)

    Fel'dgandler, Eh.G.; Levin, F.L.; Moshkevich, E.A.; Shifrin, Eh.V.; Movshovich, V.S.; Pargamonov, E.A.

    1991-01-01

    Properties and structure were investigated of austenitic 03Kh18N11 and 08KhN10T steels melted at gas oxygen refining aggregates. It was established that mechanical and corrosion properties of rolling of such steels were in agreement with standard properties of metal of open melting. Sheet 08Kh18N10T steel has the level of strength and plasticity regulated for 12Kh18N10T steel. As steel of 08Kh18N10T holds the complex of high mechanical and corrosion properties, 08Kh18N10T is recommended to be replace by 12Kh18N10T with the aim of decrease of titanium usage and increase of process efficiency

  17. Effect of boron control of environment on corrosion and resistance to low-cycle corrosion fatigue in structural steels

    International Nuclear Information System (INIS)

    Babej, Yu.I.; Zhitkov, V.V.; Zvezdin, Yu.I.; Liskevich, I.Yu.; Nazarov, A.A.

    1982-01-01

    Tests of the specimens on total, contact and crevice corrosion, corrosion cracking and low-cycle fatigue are conducted for determination of corrosion and corrosion-fatigue characteristics in the 15Kh3NMFA, 10N3MFA, 10Kh16N4B, 05Kh13N6M2 structural steels, used in energetics. The environment is subjected to boron control and contacting with atmosphere for simulation of stop and operation modes of the facility. The experiments are carried out in the distilled water with 12g/l H 3 BO 3 and 10 mg/l Cl' at 25, 60, 100 deg C under contacting with atmosphere. It is established, that the pearlitic steels 15Kh3NMFA, 10N3MFA, as well as transition and martensitic 05Kh13N6M2 and 10Kh16N4B steels are highly stable to total, crevice and contact corrosion at the high parameters of aqueous boron-containing medium. Steel resistance to low-cycle fracture decreases slightly under the conditions similar to the operation ones, in the water with 12 g/l H 3 BO 3 . Durability of the pearlitic steels at the simulation of stop conditions decreases more noticeably, crack formation as a rule, initiating from corrosion spots

  18. On change of vanadium carbide state during 20Kh3MVF steel heat treatment

    International Nuclear Information System (INIS)

    Gitgarts, M.I.; Maksimenko, V.N.

    1975-01-01

    The Xray diffraction study of vanadium carbide MC has been made in the steel-20KH3MVF quenched from 970 and 1040 deg and tempered at 660 deg for 210 hrs. It has been found that the constant of the MC crystal lattice regularly varies with the temperature of isothermal hold-up. In the steel tempered after quenching two vanadium carbides of different content could co-exist simultaneously: carbide formed in the quenching process and carbide formed during tempering. The discovered effect of the temperature dependence of the MC content is, evidently, inherent also to other steels containing vanadium

  19. Superheat effect on bainite steel hardenability

    International Nuclear Information System (INIS)

    Kubachek, V.V.; Sklyuev, P.V.

    1978-01-01

    The bainite hardenability of 34KhN1M and 35 KhN1M2Ph steels has been investigated by the end-face hardening technique. It is established that, as the temperature of austenitization rises from 900 to 1280 deg C, the temperature of bainite transformation increases and bainite hardenability of the steels falls off. A repeated slow heating to 900 deg C of previously overheated 34KhN1M steel breaks up grain, lowers the temperature of the bainite transformation and raises the hardenability to values obtained with ordinary hardening from 900 deg C. A similar heating of previously overheated 35KhN1M2Ph steel is accompanied by restoration of initial coarse grains and maintenance of both the elevated bainite transformation temperature and to lower hardenability corresponding to hardening from the temperature of previous overheating

  20. Structural changes in surface layer of steel 08Kh18N10T during machining

    International Nuclear Information System (INIS)

    Palenik, J.; Vodarek, V.

    1989-01-01

    The results are reported of a study of the surface layer of steel 08Kh18N10T affected by machining. Structural changes were studied caused by finish turning and by additional roller burnishing. Multiple deformation bands were observed to occur under the given cutting conditions; they mainly consisted of deformation doublets and only in isolated cases of ε-martensite. The presence of α'-martensite was not shown in the specimen surface layer following finish turning. The deformation shear bands in the roller-burnished specimen consisted of both ε-martensite and of deformation doublets. The amount of ε-martensite in the structure was significantly higher than in the specimen worked by turning. Local presence of α'-martensite formations was observed inside the deformation bands. It thus follows that roller burnishing is unsuitable as part of the manufacture of components from steel 08Kh18N10T. (J.B.). 5 figs., 1 tab., 9 refs

  1. Study of surface layer on 08Kh15N5D2T steel

    International Nuclear Information System (INIS)

    Tyurin, A.G.; Povolotskij, V.D.; Zhivotovskij, Eh.A.; Berg, B.N.

    1986-01-01

    08Kh15N5D2T steel phase composition is investigated. Its surface layer was determined by X-ray diffraction analysis method. It is shown, that a subscale appears to be the reason for corrosion of products, made of EhP410 steel. Under the existing smelling technology the carbon content in it is ≥ 0.05%. Therefore to avoid the metal surface depletion with chromium, one must provide for titanium relation to carbon of not less than 4.5 and carry out the rolled product thermal treatment in a protective atmosphere; otherwise, the technology must include not only the removal of scale from steel but the metal subscale layer as well

  2. Chromium surface alloying of structural steels during laser treatment

    International Nuclear Information System (INIS)

    Kurov, I.E.; Nagornykh, S.N.; Sivukhin, G.A.; Solenov, S.V.

    1987-01-01

    Results of matrix alloying from the surface layer and creation of considerably increased chromium concentration in the depth which permits to increase the efficiency of laser treatment of steels (12Kh18N10T and 38KhN3M) in the process of their further mechanical polishing, are presented. The treatment was realized by continuous CO 2 -laser at different power densities and scanning rates are presented. A model describing the creation of anomalous distributions of the alloying element in steels is plotted

  3. Corrosion cracking of 03N18K1M3TYu and 02N12Kh5M3 maraging steels in chloride solutions

    Energy Technology Data Exchange (ETDEWEB)

    Pavlov, V.N.; Chumalo, G.V.; Vereshchagin, A.N.; Melekhov, R.K.

    1987-07-01

    The authors investigate the electrochemical behavior in 0.5% NaCl solution and 42% MgCl/sub 2/ solution and the tendency toward corrosion cracking was determined in boiling 0.5% chloride solution of the cobalt-containing maraging steels in the title. Weld specimens and specimens of the base metal of 03N18K1M3TYu steel were tested in 3% NaCl solution for resistance to corrosion cracking. Additional investigations were made of specimens of that steel with previously created fatigue cracks of the base metal and the weld specimens in 3% NaCl solutions, since that steel is a promising material for structures operating in sea water and low concentration chloride solutions.

  4. Ductile fracture of two-phase welds under 77K. [Steel-EhP810, steel-EhP666, steel-08Kh18N10T, steel-EhP659-VI, steel-chP810

    Energy Technology Data Exchange (ETDEWEB)

    Yushchenko, K.A.; Voronin, S.A.; Pustovit, A.I.; Shavel' , A.V.

    The effect of the type of welding and fillers on crack resistance of welded joints high-strength steel EhP810 and its various compounds with steels EhP666, 08Kh18N10T has been studied. For the welding of steel EhP810 with steels EhP810, EhP666, 08Kh18N10T electron-beam, automatic, argon tungsten arc with non-consumable electrode with various fillers, as well as argon metal-arc welding with consumable electrode, were used. It is shown, that for a joint, made by electron-beam welding, parameters sigmasub(u), Ksub(IcJ), KCV are higher than for a joint of a similar phase structure made using filler wire EhP659-VI. It is explained by the fact, that during electron-beam welding joint metal refining takes place, which removes gases. In welded joints of chP810 steel, having joints with austenitic structure, characteristic of crack resistance Ssub(c) increases by more than 0.2 mm in contrast to two-phase joints, which conventional yield strength at 77 K exceeds 1000 MPa. It is worth mentioning, that for other classes of steels formation of two-phase structure of joint increases welded joint resistance to brittle fracture. It is possible to obtain the required structure of joint with assigned level of resistance to brittle fracture by means of the use of different fillers, optimum and welding procedure, regulating the part of the basic metal in joint content.

  5. Corrosion failure of a bolt made of the 25Kh1MF material

    International Nuclear Information System (INIS)

    Liska, V.; Cechova, D.; Velkoborsky, J.

    1989-01-01

    M36x4 bolts, of which there are 222 at each nuclear power plant unit, are made of the 25Kh1MF or 38KhN3MFA steel. They are located in an environment with elevated temperature, with damp air and with boric acid. Corrosion of these bolts is due to the rather poor metallurgical quality of the steel. No inadmissible inhomogeneities of the type of lines of inclusions occur in the bolt material produced by cold rolling but defects of the type of laps were found on the threads. It is suggested that if the cold rolling technology were obviated, corrosion failure of the bolts might not occur. (M.D.). 7 figs., 3 refs

  6. Strain ageing of the 15Kh2MFA steel at 500 and 550 deg C

    International Nuclear Information System (INIS)

    Maksimovich, G.G.; Azbukin, V.G.; Krylova, R.P.; Tretyak, I.Yu.; Bardachevskaya, T.V.

    1978-01-01

    The effect of ageing at high temperatures and under high stresses on strength and plasticity of the 15Kh2MFA steel has been studied. The steel was kept at 500 and at 550 deg C for 100, 1000 and 2500 hours without stress and under stress of 0.5 and 0.9 of the long-term strength limit (sigmasub(ls)). Ageing at 500 deg C without stress and under 0.5 sigmasub(ls) changed neither strength nor plasticity of the steel; under 0.9 sigmasub(ls) the strength somewhat decreased. Ageing at 550 deg C for 1000 hours resulted in an appreciable stress drop

  7. Neutron diffraction study of a nitrogen martensitic steel 0Kh16N4AB under load

    Czech Academy of Sciences Publication Activity Database

    Sumin, V. V.; Papushkin, I.V.; Bannykh, O.A.; Blinov, V.M.; Lukáš, Petr

    2008-01-01

    Roč. 105, č. 1 (2008), s. 88-91 ISSN 0031-918X Institutional research plan: CEZ:AV0Z10480505 Keywords : steel 0Kh16N4AB * neutron diffraction * FSD Subject RIV: BG - Nuclear, Atomic and Molecular Physics , Colliders Impact factor: 0.412, year: 2008

  8. Changes in structure and phase composition of chromium diffusion layer on stainless steels after long annealing

    International Nuclear Information System (INIS)

    Knyazev, E.V.; Voshedchenko, B.M.; Voskresenskij, Yu.A.

    1985-01-01

    A study was made on the effect of elevated temperatures UU and long holdings at heat on structure, phase composition and properties of chromium diffusion layer on austenitic chromium-nickel stainless steels 10Kh18N10TVD, 10Kh15N30M4B, 10Kh11N23T3MR, 10Kh21N28V6M3. The following mechanism of processes taking place in diffusion chromium layer is presented. The steady drop of chromium concentrations is observed after diffusion saturation. Chromium redistribution related with system transformation to more equilibrium state and simultaneous decarburization of steel surfaces takes place in diffusion layers of 10Kh15N30M4B and 10Kh21N28V6M3 steels after annealing at different temperatures and holdings at heat. Decarburization of steel surface layers is practically excluded in diffusion layers of 10Kh18N10T-VD and 10Kh11N23T3MR steels. Diffusion chromium-saturated layer stays effective only on 10Kh18N10T-VD and 10Kh11N23T3MR steels on heating up to 1000 deq C with holding up to 250 h

  9. Preliminary tension effect on low-cycle fatigue of 40Kh13 steel in gaseous hydrogen

    International Nuclear Information System (INIS)

    Romaniv, A.N.

    1984-01-01

    Comparative bending tests of specimens deformed by tension at 65, 18 and 30% in hydrogen and vacuum were accomplished to reveal the effect of preliminary tension on low-cycle fatigue strength of 40Kh13 martensitic steel. It was found that small amounts of preliminary strains induced a considerable decrease in low-cycle durability in vacuum and hydrogen which was connected with developing defects arising at the early stages of plastic deformation. A rather high degree of preliminary tension promoted steel homogenization, hydrogen embrittlement decrease and service behaviour improvement

  10. Steel corrosion in tributyl phosphate in the presence of water and ethyl mercaptan

    International Nuclear Information System (INIS)

    Pischik, L.M.; Tsinman, A.I.

    1979-01-01

    Studied is the corrosion of steels St3, 15Kh5M, 08Kh13, 10Kh14G14N4T, 08Kh18G8N2T, 10Kh17N13M2T in TBP, in mixtures of TBP with ethyl mercaptan (EM) and two-phase systems TBP-water and TBP-water-EM at 50-150 deg. In pure TBP St3 corrosion rate is low even at 150 deg. In the presence of water St 3 strongly corrodes at above 50 deg temperature in organic and water layers and also in gas phase. The steel-08Kh18G8N2T at 90 deg in acid TBP is passive and its corrosion rate is lower than 0.01 mm/year. In identical conditions the resistance of stainless steels increases together with chromium content but in TBP with acid number 100 and above at 150 deg all tested steels including steel-10Kh17N13M2T are slightly resistant. Thus, even in absence of corrosion active additions of EM the mixture of TBP-water at higher temperature is agressive in relation not only to carbon steel but also to stainless steels

  11. Heating temperature effect on ferritic grain size of rotor steel

    International Nuclear Information System (INIS)

    Cheremnykh, V.G.; Derevyankin, E.V.; Sakulin, A.A.

    1983-01-01

    The heating temperature effect on ferritic grain size of two steels 13Kh1M1FA and 25Kh1M1FA is evaluated. It is shown that exposure time increase at heating temperatures below 1000 deg C up to 10h changes but slightly the size of the Cr-Mo-V ferritic grain of rotor steel cooled with 25 deg C/h rate. Heating up to 1000 deg C and above leads to substantial ferritic grain growth. The kinetics of ferritic grain growth is determined by the behaviour of phases controlling the austenitic grain growth, such as carbonitrides VCsub(0.14)Nsub(0.78) in 13Kh1M1FA steel and VCsub(0.18)Nsub(0.72) in 25Kh1M1FA steel. Reduction of carbon and alloying elements content in steel composition observed at the liquation over rotor length leads to a certain decrease of ferritic grain resistance to super heating

  12. Estimation of structural strength of 38KhN3MFA steel, melted using different methods

    International Nuclear Information System (INIS)

    Kudrya, A.V.; Mochalov, B.V.; Fadeev, Yu.I.

    1982-01-01

    Quantity of steel melted by different methods using criteria of fracture mechanics is evaluated. Three technological variants of the 38KhN3MFA steel melting: acid Martin steel prepared by the duplex-process (melt 1); the main Martin steel melting with deoxidation and alloying in a ladle by liquid alloy and treatment with synthetic slag with argon purging after production (melt 2) and its electroslag remelt - ESP process (melt 3) are investigated. The analysis of the investigated melts has revealed that crack resistances of the acid Martin steel is higher than that of other melts at practically similar standard mechanical properties with 0.35 probability at 0.05 significance level in the low-tempered state; in the tempered state the best crack resistance is observed in the ESP main Martin steel. Metal of the main Martin melting has lower crack resistance as compared with other meltings at both strength levels. The results of the work point out the necessity of applying the criteria of fracture mechanics for obtaining an objective evaluation of the steel quality

  13. Electroplastic drawing of stainless steels

    International Nuclear Information System (INIS)

    Troitskij, O.A.; Spitsyn, V.I.; Sokolov, N.V.; Ryzhkov, V.G.

    1977-01-01

    Effect of electroplastic drawing on mechanical, magnetic and electrical properties of wire of 12Kh18N10T and Kh13N13M2 steels was studied. Pulse, direct and alternating currents were used. Direct and alternating current densities were 400 A/mm 2 , mean density of pulse current was 200 A/mm 2 . The investigations have shown that the current density increase results in decreasing the wire strengthening intensity though in increasing plastic properties. As a result of electroplastic drawing the growth of magnetic characteristics of wire occurs

  14. Effect of Heat Treatment on the Structure and Properties of Die Steel 70Kh3G2FTR

    Science.gov (United States)

    Krylova, S. E.; Kletsova, O. A.; Gryzunov, V. I.; Fot, A. P.; Tavtilov, I. Sh.

    2018-01-01

    The effect of heat treatment parameters on the properties and structural and phase composition of a promising die steel 70Kh3G2FTR for hot deformation is studied. The temperature-and-stress state of a hammer die under a heat treatment is simulated.

  15. Praktik Pemikiran Inklusif-Sosial KH M Sholeh Bahruddin Ngalah sebagai Manifestasi Pendidikan Multikultural Pesantren

    Directory of Open Access Journals (Sweden)

    M Anang Sholikhudin

    2016-12-01

    Full Text Available Dalam sejarah hidupnya, praktik pemikiran inklusif-sosial Kiai Sholeh sangat dipengaruhi oleh beberapa hal. Pertama, atas perintah ayahanda dengan pesan seperti berikut: “sak temene dek pasar, dek masjid, dek dalan, kabeh iku dulurmu (sesungguhnya baik di pasar, di masjid, maupun di jalanan, di seluruh tempat itu ada saudaramu.” Kedua, penerapan teori Abraham, yakni mencontoh perilaku ayahanda KH M Bahruddin Kalam (almarhum dan juga perilaku kakek KH M Kalam (almarhum. Ketiga, praktik dari rukun Tarekat Naqshabandiyah pada poin kelima dan keenam, yakni “ambugusi kabeh konco, cilik gede, lanang wadon, enom tuo, lan ambagusi kabeh makhluk (bergaul secara baik dengan semua teman, baik kecil maupun besar, laki-laki maupun perempuan, muda maupun tua, dan bergaul secara baik dengan semua makhluk.” Penelitian ini memfokuskan pada praktik pemikiran inklusif-sosial KH M Sholeh Bahruddin dengan model studi kasus, pendekatan yang dipakai adalah expose facto. Data diambil melalui observasi, wawancara serta dokumentasi. Penelitian menyimpulkan bahwa praktik pemikiran inklusif-sosial KH.. M. Sholeh Bahruddin sebenarnya mempertemukan misi perintah masing-masing agama (Islam, Kristen, Katolik, Budha dan Konghucu untuk membangun perdamaian, keamanan dan memelihara kasih sayang bersama-sama dan meminimalisir terjadinya konflik agama. || In the history of his life, the practice of inclusive social thought by Kiai Sholeh greatly influenced by several things. First, on the orders of his father with the following message: “In the markets, in the mosques, as well as on the streets, all over the places there are your brothers.” Secondly, the application of Abraham’s theory, which was practiced by KH M Bahruddin Kalam, the father (deceased of Kiai Sholeh, as well as KH M Kalam, the grandfather (deceased of Kiai Sholeh. Third, the practice of the Naqshabandi pillars that say: “being good with all friends, both small and great, both men and women, young

  16. Irradiation and annealing behavior of 15Kh2MFA reactor pressure vessel steel

    International Nuclear Information System (INIS)

    Popp, K.; Bergmann, U.; Bergner, F.; Hampe, E.; Leonhardt, W.D.; Schuetzler, H.P.; Viehrig, H.W.

    1992-01-01

    This work deals with the mechanical properties of RPV steels used WWER-440. The materials under investigation were a forging (base metal 15Kh2MFA) and the corresponding weld. Charpy V-notch specimens and tensile test specimens were irradiated in the WWER-2 Rheinsberg at about 270 C up to the two neutron fluence levels of 4 x 10 18 and 5 x 10 19 n/cm 2 (E>1MeV). Post-irradiation annealing heat treatments were performed, among others a 475 C/152 h treatment of technical interest. (orig.)

  17. Effect of nonmetallic inclusions on anisotropy of ductility in 35KhN3MFA steel forgings

    International Nuclear Information System (INIS)

    Shtremel', M.A.; Yavojskij, V.I.; Volkov, V.A.; Chursin, G.M.; Chukhlov, V.I.; Fetisov, G.I.; Mochalin, N.K.; Smol'yaninov, L.V.

    1980-01-01

    Characteristics of nonmetaltic inclusions and anizotropy of ductility and of impuct strength of forgings of the 35KhN3MFA steel are compared at different variants of melting and outer-furnace treatment. It is shown that method of melting rugulates anisotropy of ductility primarily through deformability of large inclusions during forging. Deformability of inclusions considerably changes due to introduction of silicocalcium in iron mold [ru

  18. Effect of partial oxygen pressure on physicochemical properties of Kh18N10T steel at isothermal oxidation

    International Nuclear Information System (INIS)

    Alekseev, V.N.; Oshe, E.K.; Fokin, M.N.; Bogdanova, S.V.; Loskutov, A.I.

    1990-01-01

    Auger-electron spectroscopy, photoelectric polarization, conductometry methods have been used to analyze chemical and defect composition of surface oxide layers, formed on stainless steel Kh18N10T in vacuum (10 -9 - 10 -2 torr) and at temperatures 593-673 K. The boundary conditions of manifestation of extermal behaviour of the dependence of the surface oxide growth rate at isothermal oxidation of this steel are determined. The relation between passivation properties of the surface oxide and the magnitude of the edge angle of the surface wetting with molten tin is revealed

  19. Cyclic crack resistance of anticorrosion cladding-15Kh2MFA steel joint

    International Nuclear Information System (INIS)

    Zvezdin, Yu.I.; Nikiforchin, G.N.; Timofeev, B.T.; Zima, Yu.V.; Andrusiv, B.N.

    1985-01-01

    Cyclie crack resistance of transition zone in austenitic cladding steel 15Kh2MFA joint is studied, taking into account the geometry of fatigue cracks, fracture micromechanism and crack closure effect. Kinetics of crack development from the cladding to the basic metal and vice versa is considered. Microstructure of transition zone is investigated. The results obtained are considered as applied to WWER. It is emphasized, that the braking of fatigue cracks is observed at low asymmetry of loading cycle. Increased loading asymmetry accelerates sharply the alloy fracture due to the growth of subcladding crack, at that, the direction of crack propagation and the structure of transition zone are not of great importance

  20. Local corrosion of high alloy steels under biodeposits

    International Nuclear Information System (INIS)

    Korovyakova, M.D.; Nikitin, V.M.; Speshneva, N.V.

    1999-01-01

    Impact of the bacteriozenosis different structural-functional state under biodeposits on corrosion resistance of the 12Kh18N10T and Kh18N10T high-alloy steels in the natural seawater is studied. It is shown that saturation of natural micro communities by separate aerobic and facultative-anaerobic bacterial monocultures increases corrosion resistance of these steels by their overgrow with biodeposits [ru

  1. Investigation into the Cyclic Strength of the Bodies of Steam Shutoff Valves from 10Kh9MFB-Sh Steel

    Science.gov (United States)

    Skorobogatykh, V. N.; Kunavin, S. A.; Prudnikov, D. A.; Shchenkova, I. A.; Bazhenov, A. M.; Zadoinyi, V. A.; Starkovskii, G. L.

    2018-02-01

    Steam shutoff valves are operated under complex loading conditions at thermal and nuclear power stations. In addition to exposure to high temperature and stresses resulting in fatigue, these valves are subjected to cyclic loads in heating-up-cooling down, opening-closing, etc. cycles. The number of these cycles to be specified in designing the valves should not exceed the maximum allowable value. Hence, the problem of cyclic failure rate of steam shutoff valve bodies is critical. This paper continues the previous publications about properties of the construction material for steam shutoff valve bodies (grade 10Kh9MFB-Sh steel) produced by electroslag melting and gives the results of investigation into the cyclic strength of this material. Fatigue curves for the steal used for manufacturing steam shutoff valve bodies are presented. The experimental data are compared with the calculated fatigue curves plotted using the procedures outlined in PNAE G-002-986 and RD 10-249-98. It is confirmed that these procedures may be used in designing valve bodies from 10Kh9MFB-Sh steel. The effect of the cyclic damage after preliminary cyclic loading of the specimens according to the prescribed load conditions on the high-temperature strength of the steel is examined. The influence of cyclic failure rate on the long-term strength was investigated using cylindrical specimens with a smooth working section in the as-made conditions and after two regimes of preliminary cyclic loading (training) at a working temperature of 570°C and the number of load cycles exceeding the design value, which was 2 × 103 cycles. The experiments corroborated that the material (10Kh9MFB-Sh steel) of the body manufactured by the method of electroslag melting had high resistance to cyclic failure rate. No effect of cyclic damages in the metal of the investigated specimens on the high-temperature strength has been found.

  2. Effect of smelt aluminium on mechanical properties of steels

    International Nuclear Information System (INIS)

    Ryabov, V.R.; Dykhno, I.S.; Deev, G.F.; Karikh, V.V.

    1987-01-01

    Effect of smelt aluminium on mechanical properties of armco-iron and 12 Kh18N10T steel is studied. It is stated that in smelt aluminium and aluminium alloy contact with armco-iron the sample ductility is decreased. Corrosion effect of smelt alluminium on (18Kh15N5AM3) steel in the form of reinforced wire in aluminium-steel KAS-1A composite material is investigted. It is stated in experiment that during smelt alluminium-steel contact interaction of heterogeneous phases takes place

  3. Annealing effect on restoration of irradiation steel properties

    International Nuclear Information System (INIS)

    Vishkarev, O.M.; Kolesova, T.N.; Myasnikova, K.P.; Pecherin, A.M.; Shamardin, V.K.

    1986-01-01

    The effect of temperature and annealing time on the restoration of properties of the 15Kh2NMFAA and 15Kh2MFA steels after irradiation at 285 deg with the fluence of 6x10 23 neutr/m 2 (E>0.5 MeV) is studied. Microhardness (H μ ) restoration in the irradiated 15Kh2NMFAA steel is shown to start from 350 deg C annealing temperature. The complete microhardness restoration is observed at the annealing temperature of 500 deg C for 10 hours

  4. Development and industrial mastering hot rolling procedure for low-ductile steels and alloys

    International Nuclear Information System (INIS)

    Degterenko, V.K.; Sokolov, V.A.

    1980-01-01

    The technique for the development of the sheet hot rolling procedure for low-ductile steels and alloys (0Kh17N14M2, 12Kh21N5T, 20Kh25N20C2,40Kh13, 36NKhTYu etc.) is proposed, using plastometer which permits to obtain the data on the deformation resistance in the wide range of temperatures (800-1300 deg C), of deformation degrees (0.1-0.3) and deformation rates (0.001-300 c -1 ). With the help of the plastometric data processed on the computer the calculation of the rolling regimes for the sheet with improved surface quality is carried out at the more uniform loading on the mill stands

  5. Low-temperature nitriding of austenitic steel in a vibrofluidized bed

    Science.gov (United States)

    Baraz, V. R.; Grachev, S. V.

    1999-11-01

    The prospects for use of a vibrofluidized bed (VFB) for low-temperature nitrogen saturation of high-strength austenitic steel based on Cr-Ni-Mn (12Kh17N8G2S2MF) are considered. The positive effect of preliminary plastic deformation on the intensity of nitriding is described. The temperature and time parameters of nitriding in a VFB for strain-aging austenitic steel 12Kh17N8G2S2MF are shown to be adequate for the regimes of the final heat-treatment operation of aging. This creates the possibility of combining the operations of surface alloying and strain aging into a single cycle. This combined treatment increases substantially the resistance of the steel to cyclic loads while preserving the strength parameters. It is shown that the presented method of low-temperature nitriding in a VFB is expedient for improving the service characteristics of austenitic steel 12Kh17N8G2S2MF used for production of force springs of automobile brake systems.

  6. Corrosion behaviour of stainless steels by internal friction method

    International Nuclear Information System (INIS)

    Postnikov, V.S.; Kovalevskij, V.I.

    1987-01-01

    Corrosion of austenite chromium-nickel stainless steels 12 Kh18N9, 12Kh18N9T, 12Kh18N10 and 12Kh18N10T is investigated. Wire samples 0.7...0.8 mm in diameter before tests were subjected to quenching in water from the temperature of 1050...1100 deg C and part of them - to tempering at 650 deg C for 2 h. Pitting corrosion was brought about by different concentration of iron chloride solutions (C FeCl 3 ). Total corrosion has a slight effect on the character of IF (internal friction) variation that increases without the whole test period up to the moment when mechanical strength of the sample

  7. Plasticity of low carbon stainless steels

    International Nuclear Information System (INIS)

    Bulat, S.I.; Fel'dgandler, Eh.G.; Kareva, E.N.

    1975-01-01

    In the temperature range 800-1200 0 C and with strain rates of from 10 -3 to 3 s -1 , austenitic (000Kh18N12) and austenitic-ferrite (000Kh26N6) very low carbon stainless steels containing 0.02-0.03% C exhibit no higher resilience than corresponding ordinary steels containing 0.10-0.12% C. However, the plasticity of such steels (particularly two-phase steels) at 900-1100 0 C is appreciably inferior owing to the development of intergranular brittle fracture. Pressure treatment preceded by partial cooling of the surface to 850 0 C yields rolled and forged products with acceptable indices but is inconvenient technically. At the Zlatoustovsk and Ashin metallurgical plants successful tests have been performed involving the forging and rolling of such steels heated to 1280-1300 0 C without partial cooling; it was necessary to improve the killing conditions, correct the chemical composition (increasing the proportion of ferrite) and take measures against heat loss. (author)

  8. Effect of heat treatment and plastic deformation on the structure and the mechanical properties of nitrogen-bearing 04N9Kh2A steel

    Science.gov (United States)

    Blinov, V. M.; Bannykh, O. A.; Lukin, E. I.; Kostina, M. V.; Blinov, E. V.

    2014-11-01

    The effect of the conditions of heat treatment and plastic deformation on the structure and the mechanical properties of low-carbon martensitic nickel steel (9 wt % Ni) with an overequilibrium nitrogen content is studied. The limiting strain to failure of 04N9Kh2A steel is found to be 40% at a rolling temperature of 20°C and 80% at a rolling temperature of 900°C. Significant strengthening of the steel (σ0.2 = 1089 MPa) is obtained after rolling at a reduction of 40% at 20°C. The start and final temperatures of the α → γ transformation on heating and those of the γ → α transformation on cooling are determined by dilatometry. The specific features of the formation of the steel structure have been revealed as functions of the annealing and tempering temperatures. Electron-microscopic studies show that, after quenching from 850°C and tempering at 600°C for 1 h, the structure contains packet martensite with thin interlayers of retained austenite between martensite crystals. The strength of the nitrogen-bearing 04N9Kh2A steel after quenching from 850 and 900°C, cooling in water, and subsequent tempering at 500°C for 1 h is significantly higher than that of carboncontaining 0H9 steel used in cryogenic engineering.

  9. Nitrogen effect on the tendency of Cr-Ni-MN steels to delayed fracture under stress and hydrogen effects

    International Nuclear Information System (INIS)

    Suvorova, S.O.; Fillipov, G.A.

    1996-01-01

    Austenitic steels types 03Kh17N16G10AM5, 03Kh6N12G10AM5 and 07Kh13AG20 with various nitrogen contents were studied for their tendency to delayed fracture using mechanical tests, fractography and X ray diffraction analysis. The steel type 07Kh13G20 exhibited the highest strength in the initial state but showed an increase tendency to delayed fracture after hydrogenation. It is underlined that nitrogen additions essentially intensify the tendency of cold worked steels to delayed fracture. This fact should be taken into account when using nitrogen-containing Cr-Ni-Mn steels under severe operational conditions. 4 refs., 2 tabs

  10. Effect of nickel and MnS inclusions in the metal on the pitting corrosion of low-carbon stainless steels

    International Nuclear Information System (INIS)

    Frejman, L.I.; Nguen, The Dong; Volkov, D.E.; Konnov, Yu.P.

    1986-01-01

    The resistance to pitting corrosion of steels on the 03Kh17-03Kh18 base containing up to 20 % Ni at different levels of S and Mn impurities contamination is investigated. It is shown that up to 50 % of nickel introduced into ordinary steels with 5-6 % Ni is spent to compensate the resistance decrease caused by MnS inclusions. Full compensation is not attained even in the 10-20 %. Ni range in which nickel practically does not affect the resistance of neither ordinary, nor pure (without MnS) steels. Titanium introduction into ordinary steel on the Kh22N6 base permits to surpass the level of 03Kh17N3 pure steel resistance and attain the level of 03Kh17N6 pure steel almost by all characteristics (including passivated characteristics in sulfuric acid) besides pitting repassivity. In this property pure steels with Ni >or approx. 3 % surpass even the molybdenum containing 03Kh21NbM2T ordinary steel though they by far concede by passivation in sulfuric acid

  11. On the low-cycle fracture of chromium-nickel-molybdenum structural steels in seawater

    International Nuclear Information System (INIS)

    Karpenko, G.V.; Kobzaruk, A.V.; Malyshevskij, V.A.; Shul'te, A.Yu.; Rybin, V.V.; Silaev, I.I.

    1977-01-01

    The processes of low-cycle fracture of the chrome-nickel-molybdenum steels 15KhN5MF, 12KhN4MF and 15KhN3M in air, and in sea water have been investigated by the optical microscopy method, and electron microscopic examination of thin films. Bringing no change in the fracture character, sea water produces a speeding-up effect on the low-cycle fatigue fracture process. During long-time corrosion fatigue testing considerable importance lies with the electrochemical corrosion factor expediting the occurrence of corrosive pits acting as crack-initiation nuclei, fatigue crack attack, accumulation of corrosion products in fatigue cracks, etc

  12. Effect of hydrostatic pressure on phase transformations in Kh17N8 steel during deformation

    International Nuclear Information System (INIS)

    Eshchenko, R.N.; Teplov, V.A.

    1984-01-01

    The phase composition and structure of Kh17N8 steel strained to different degrees under atmospheric pressure and 1700 MPa are investigated. It has been found that deformation at 1700 MPa causes α and epsilon-martensite formation, the same deformation under atmospheric pressure - only α-martensite formation. The amount of the formed α-martensite is not changed with application of hydrostatic pressure. Electron-microscopic observations have shown that the dispersion of α-martensite formed under pressure is higher than in the absence of pressure; no interconnection in formation of α and epsilon-martensite in samples strained under pressure has been observed

  13. The effect of chromium diffusion redistribution on wear resistance of carburized 3Kh13 steel

    International Nuclear Information System (INIS)

    Shcherbedinskij, G.V.; Shumakov, A.I.; Zemskij, S.V.; Pereverzev, V.M.

    1977-01-01

    The redistribution of chromium in steel 3Kh13 on carburization in a high-activity carburizer and the wear-resistance of the steel have been investigated. Surface layers with an increased chromium concentration show the highest wear-resistance. The chromium content in the surface layer increases due to its diffusion from the interior. The distribution of carbon and chromium in the carburized layers has been studied with the aid of the radioactive isotope 14 C by the method of layer-by-layer spectral analysis on a vacuum quantometer, layer-by-layer chemical and X-ray structure analysis. The composition of the carbides has been determined by physicochemical analysis. It has been established that the carburized layer can be divided into four zones with respect to its phase composition: first zone - hematite and spinal with 0.5-2.0% C; second zone - solid carbides (Fe,Cr) 7 C 3 ; up to 5% C; third zone - globular carbides in a troostite matrix (Cr,Fe) 7 C 3 and Cr 23 C 6 ; up to 3.5% C; fourth, transitional, zone - troostite carbide mixture Cr 23 C 6 ; up to 1% C. The chromium diffusion in the carburized layer is faster than in the initial austenite. The chromium counterdiffusion is due to the development of a zone of solid carbides M 7 C 3

  14. Investigation of Creep Processes and Microdamages in 10Kh9V2MFBR-Sh High-Chromium Steel

    Science.gov (United States)

    Grin', E. A.; Pchelintsev, A. V.

    2018-01-01

    During the modernization and the new construction of power units at TPPs in Russia, high-chromium martensitic steels with higher heat-resistant properties than the traditional perlite steels are increasingly used as structural materials. High-chromium steels have a necessary regulatory support for their use in domestic power engineering. However, up to the present time, the issue of assessing the quality of these steels at the analysis of their state during long-term operation remains open. The article proposed is one of the first attempts to create a system of quality criteria for martensitic steels based on their microdamage parameters. Tests were carried out on the long-term strength and creep of samples from 10Kh9V2MFBR-Sh steel at high temperatures with the construction of creep curves in relative coordinates "deformation related to the deformation of fracture, current time related to time to failure." For some samples, the tests were interrupted and the metal was subjected to metallographic studies consisting of the analysis of microdamage with reference to the accumulated creep strain. It has been shown experimentally that the deformation curve of high-chromium steel differs from the analogous curve of pearlitic steel by a longer and flat section of steady creep and by a sharper transition to the third accelerated creep stage, which has a very short time period (approximately 10% of the total durability). The tendency to the increase in the microdamage of the structure of steel as the accumulated creep strain increases with time was confirmed. The beginning of transition to the final creep phase is characterized by the formation of contours of future pore chains and by the appearance of individual large pores of up to 6 μm in size, the presence of which in the microstructure of the martensitic steel indicates a very significant accumulation of creep strain, and corresponds to the predestruction stage of metal. It is necessary to continue the research to

  15. About Moral Ideals of Turkic Philosopher M.Kh. Dulaty

    Directory of Open Access Journals (Sweden)

    Botagoz S.Asankulova

    2015-04-01

    Full Text Available The ideas of moral upbringing during the period of Kazakh kingdom on the example of M.Kh.Dulaty ҆s work «Tarikh-i-Rashidi» are given in the article. The main idea is historical-pedagogical aspect of investigation of moral upbringing problems. Genesis of progressive ideas in this direction is the basis of historical experience, which allows to define the dynamics of upbringing process contributing to the moral perfection of personality.

  16. Corrosion resistance of heat exchange equipment in hydrotreating Orenburg Condensate

    International Nuclear Information System (INIS)

    Teslya, B.M.; Burlov, V.V.; Parputs, I.V.; Parputs, T.P.

    1986-01-01

    The authors study the corrosion resistance of materials of construction and select appropriate materials for the fabrication of heat exchange equipment that will be serviceable under hydrotreating conditions. This paper discusses the Orenburg condensate hydrotreating unit which has been shut down repeatedly for repair because of corrosion damage to components of heat exchangers in the reactor section: tube bundles (08Kh18N10T steel), corrugated compensators (12Kh18N10T steel), and pins of the floating heads (37Kh13N8G8MFB steel). The authors recommend that the tube bundles and the compensators in heat exchangers in the reaction section should be fabricated of 08Kh21N6M2T or 10Kh17N13M2T steel. The pins have been replaced by new pins made of 10Kh17N13 X M2T steel, increasing the service life from 6-12 months to 2 years

  17. Effect of partial oxygen pressure on physicochemical properties of Kh18N10T steel at isothermal oxidation. Vliyanie partsial'nogo davleniya kisloroda na fiziko-khimicheskie svojstva poverkhnosti stali Kh18N10T pri izotermicheskom okislenii

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, V N; Oshe, E K; Fokin, M N; Bogdanova, S V; Loskutov, A I [AN SSSR, Moscow (USSR). Inst. Fizicheskoj Khimii

    1990-10-01

    Auger-electron spectroscopy, photoelectric polarization, conductometry methods have been used to analyze chemical and defect composition of surface oxide layers, formed on stainless steel Kh18N10T in vacuum (10{sup -9} - 10{sup -2} torr) and at temperatures 593-673 K. The boundary conditions of manifestation of extermal behaviour of the dependence of the surface oxide growth rate at isothermal oxidation of this steel are determined. The relation between passivation properties of the surface oxide and the magnitude of the edge angle of the surface wetting with molten tin is revealed.

  18. Corrosion of chromium, nickel, titanium and steels in solutions of sodium and ammonium thiosulfates

    International Nuclear Information System (INIS)

    Grebenshchikova, S.V.; Kochergin, V.P.; Doronina, I.V.

    1983-01-01

    Results of gravimetric determinatiion of average rate of chromium, nickel, titatnium and steels 12Kh18N10T and VSt.3 corrosion rate in solutions 50 mass.% (NH 4 ) 2 S 2 O 3 and Na 2 S 2 O 3 in the air and nitrogen atmosphere at 333 K have been generalized. Anodic polarization curves are recorded and stationary potentials of metals and steels under the conditions are measured. It is shown that in (NH 4 ) 2 S 2 O 3 solution the rate of metal and steels corrosion is higher than in Na 2 S 2 O 3 solution indepenent of the nature of gaseous medium contacting with solution. In the series Ni → VSt.3 → 12Kh18N10T → VT1 → chromium in (NH 4 ) 2 S 2 O 3 and Na 2 S 2 O 3 solutions at 333 K corrosion resistance increases. Chromium, titanium and chromium-nickel steel 12Kh18N10T possess a high corrosion resistance

  19. Effect of silicon on the structure, tribological behaviour, and mechanical properties of nitrogen-containing chromium-manganese austenitic steels

    International Nuclear Information System (INIS)

    Korshunov, L.G.; Chernenko, N.L.; Gojkhenberg, Yu.N.

    2003-01-01

    The effect of silicon in quantity of 3.5-4.5 mass. % on tribological behaviour is studied for nitrogen-bearing (0.20-0.52 mass. % of nitrogen) chromium-manganese austenitic steels (10Kh15G23S4A0.20, 10Kh16G17N3S4A0.30, 10Kh19G20NS4A0.50, 12Kh19G19NS2A0.50, 10Kh18G19A0.50, 08Kh16G8N10S4A0.18). Mechanical properties and corrosion resistance of the steels are determined. Using metallographic, x-ray diffraction and electron microscopical methods a study is made into structural transformations running in the steels considered under friction and static tension. It is shown that additional silicon alloying of nitrogen-bearing chromium-manganese austenitic steels results in an essential increase of adhesion wear resistance of the materials on retention of low friction coefficient (f=0.25-0.33). A strong silicon effect on steel tribological behaviour is related with planar slip activation and with an increase of austenite strength and heat resistance [ru

  20. 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

  1. Parametrical limits of SCC-susceptibility of austenitic and austenitic-ferritic Cr-Ni steels

    International Nuclear Information System (INIS)

    Starosvetskij, D.I.; Baru, R.L.; Bondarenko, A.I.; Bogoyavlenskij, V.L.; Timonin, V.A.

    1990-01-01

    Comparative investigations into corrosion cracking (CC) of austenitic (12Kh18N10T) and austenitic-ferritic (08Kh22N6T) chromium-nickel steels are performed for various chloride media in a wide range of chloride concentrations and temperatures. It is shown that the ratio between steels in terms of their CC-susceptibility is not definite and can undergo a reversal depending on parameters of medium, level and conditions of loading. Differences in mechanisms of corrosion cracking of austenitic and austenitic-ferritic steels are established

  2. Close toleranoe forging of chromium steel blades for powerful steam turbines

    International Nuclear Information System (INIS)

    Shastin, Eh.G.; Kositskij, Yu.N.; Lyubchits, G.A.

    1989-01-01

    Work on simulating technological process on die-forging hammer was performed in order to reduce the preparation period bringing technology of close tolerance forging of turbine blades to a commercial level. A special attention was paid to development of accurate forming of forgings of 20Kh13Sh, 12Kh13 and 15Kh11MFSh steels on screw presses with nominal effort equal to 80 and 144 MN

  3. Effect of helium ion bombardment on hydrogen behaviour in stainless steel

    International Nuclear Information System (INIS)

    Guseva, M.I.; Stolyarova, V.G.; Gorbatov, E.A.

    1987-01-01

    The effect of helium ion bombardment on hydrogen behaviour in 12Kh18N10T stainless steel is investigated. Helium and hydrogen ion bombardment was conducted in the ILU-3 ion accelerator; the fluence and energy made up 10 16 -5x10 17 cm -2 , 30 keV and 10 16 -5x10 18 cm -2 , 10 keV respectively. The method of recoil nuclei was used for determination of helium and hydrogen content. Successive implantation of helium and hydrogen ions into 12Kh18N10T stainless steel results in hydrogen capture by defects formed by helium ions

  4. Specific features of precipitation hardening of austenitic steels with various base. 2. Kinetics and mechanism of carbide precipitation

    International Nuclear Information System (INIS)

    Kositsyna, I.I.; Sagaradze, V.V.; Khakimova, O.N.

    1997-01-01

    Electron microscopic studies were carried out to determine the kinetics and mechanisms of precipitation hardening in Fe-Mn, Fe-Mn-Cr, Fe-Cr-Mn-N, Fe-Cr-Ni and Fe-Ni base stainless steels (45G20M2F2, 50Kh16G15N6M2F2, 45Kh18N10G10M2F2, 40Kh18Ni18M2F2, 45N26M2F2). The steels were heat treated under various conditions. It is revealed that in manganese steels the particles of vanadium carbide nucleate according to homogeneous mechanism at all aging temperatures (600-750 deg C). The presence of chromium in the matrix promotes the transition to heterogeneous mechanism of carbide nucleation and growth. With nickel content increasing the plasticity of precipitation hardened steels gets better due to more intense diffusion of atoms and vacancies to grain boundaries and, hence, the widening of near-boundary zones free of carbide particles

  5. Radiation embrittlement of WWER 440 pressure vessel steel and of some improved steels by western producers

    International Nuclear Information System (INIS)

    Koutsky, J.; Vacek, M.; Stoces, B.; Pav, T.; Otruba, J.; Novosad, P.; Brumovsky, M.

    1982-01-01

    The resistance was studied of Cr-Mo-V type steel 15Kh2MFA to radiation embrittlement at an irradiation temperature of around 288 degC. Studied was the steel used for the manufacture of the pressure vessel of the Paks nuclear reactor in Hungary. The obtained results of radiation embrittlement and hardening of steel 15Kh2MFA were compared with similar values of Mn-Ni-Mo type steels A 533-B and A 508 manufactured by leading western manufacturers within the international research programme coordinated by the IAEA. It was found that the resistance of steel 15Kh2MFA to radiation embrittlement is comparable with steels A 533-B and A 508 by western manufacturers. (author)

  6. Structural steels for power generating equipment and heat and chemical heat treatments

    International Nuclear Information System (INIS)

    Astaf'ev, A.A.

    1979-01-01

    Development of structural steels for power generating equipment and for reactor engineering, in particular, is elucidated. Noted is utilization of the 15Kh2NMFA steels for the WWER-1000 reactor vessels, the 10GN2MFA steels for steam generators, pressurizers, vessels of the automatic emergency shut down and safety system; the 00Kh12N3DL steel for cast pump vessels and main locking bars. The recommendations on heat treatment of big forgings, for instance, ensuring the necessary complex of mechanical properties are given. Diffusion chromizing with subsequent nitriding of austenitic steels which increase durability of the components in BN reactors more than 4 times, is practised on a large scale

  7. X-ray spectrum microanalysis of copper and stainless steel surface layer after electroerosion machining

    International Nuclear Information System (INIS)

    Abdukarimov, Eh.T.; Saidinov, S.Ya.

    1989-01-01

    The results of experimental investigations of the surface layer of copper and steel 12Kh18N10T after electroerrosion treatment by a rotating tungsten electrode in natural and distilled water are presented. It is established that the quantity of electrode material transferred to the surface of the steel treated grows with the spark discharge energy increase. Tungsten concentration in the surface layer reaches 5-10% with the average depth of penetration 40-50 μm

  8. Low-temperature cyclic cracking resistance of Fe-Cr-Ni and Fe-Cr-Mn steels welded joints

    International Nuclear Information System (INIS)

    Ostash, O.P.; Zhmur-Klimenko, V.T.; Yarema, S.Ya.; Yushchenko, K.A.; Strok, L.P.; Belotserkovets, V.I.

    1983-01-01

    Results of further investigations into regularities of development of low-temperature fatigue fracture of welded oints in 07Kh13G20AN4 steel are presented, they are compared with analogous data traditional cryogenic 0Kh18N10T and 03Kh13AG19 steels. Welded joints have been prepared by means of automatic V-like level arc Welding of plates; 0Kh18N10T and 07Kh13G20AN4 steels have been welded by means of sv-04Kh19N9 wire, 03Kh13AG19 steel-by means of sv-07Kh13AG19 wire. Tests at almost zero (asymmetry coefficient R=0.05) cycle of extension at 15-20 Hz frequency have been conducted on 5 mm thick disk samples at 20 deg C and - 160 deg C according to the given methods. It is shown that by cyclic crack resistance of welded joint zones of 0Kh18N10T steel and chromium-manganese steels at normal temperature the 07Kh13G20AN4 steel exceeds 0Kh18N10T steel, at low temperature it yields to 0Kh18N10T only by fracture toughness of heat affected zones HAZ and weld metal (ne). 07Kh13G20AN4 steel and its welded joints as most hardened and cheap may be a good substituent for 0Kh18N10T steel. Optimization of WM alloying for increase of its cyclic fracture toughness at cryogenic temperatures is necessary

  9. Specific features of the occurrence, development, and re-compaction of spall and shear fractures in spherically-convergent shells made of unalloyed iron and some steels under their spherical explosive loading

    International Nuclear Information System (INIS)

    Kozlov, E.A.; Brichikov, S.A.; Gorbachev, D.M.; Brodova, I.G.; Yablonskikh, T.I.

    2007-01-01

    Results of comparative metallographic examination of recovered shells exposed to explosive loading in two modes (with and without a heavy casing confining explosion products scatter) are presented. The shells were made of high-purity and technical-grade unalloyed iron with the initial grain size 250 and 125 μm, steel 30KhGSA in delivery state and quenched up to HR C 35...40, austenitic stainless steel 12Kh18N10T. The heavy casing used in experiments is demonstrated to ensure a rather compact convergence of shells destroyed at high radii. In the described comparative experiments, one managed to compile the 12Kh18N10T steel shell, after it was spalled at high radii and exposed to shear fracture and spallation layer fragmentation at medium radii, into a compact sphere but failed to do the same with the 30KhGSA quenched steel shell after it was fractured according to spall and shear mechanisms at high and medium radii. Polar zones of this steel shell have obvious undercompressed areas due to significant dissipative losses to overcome the shear strength. Occurrence, development, and re-compaction of spall and shear fractures in spherically-convergent shells made of materials, which were already carefully investigated in 1D- and 2D-geometry experiments, were systematically studied in order to verify and validate new physical models of dynamic fractures, as well as up-to-date used in 1D-, 2D- and 3D-numerical algorithms [ru

  10. Stainless austenitic steels strengthened due to reversible phase transformations and by ageing

    International Nuclear Information System (INIS)

    Sagaradze, V.V.; Kositsyna, I.I.; Ozhiganov, A.V.

    1981-01-01

    The effect of the reversible phase transformations, consisting in the conduction of the direct and reverse martensite transformations and aging, during which the intermetallide γ'-phase of the composition Ni 3 Ti is formed, on the streng-thening of alloys in the Fe-Cr-Ni-Ti system is considered. Stainless austenitic steels Kh12N12T3 and Kh12N14T3, which acquire high mechanical properties: σsub(0.2)=685-785 MPa, σsub(B)=1275 MPa, delta >= 20%, as a result of reversible phase transformations and aging, are suggested. After the reversible phase transformations and ageing the steels possess a high resistance to γ-α-transformation during cold treatment [ru

  11. 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

  12. Quality of structural steel melted by single-slag process

    International Nuclear Information System (INIS)

    Levin, A.M.; Andreev, V.I.; Monastyrskij, A.V.; Drozdova, M.F.; Pashchenko, V.E.; Orzhekh, M.B.

    1982-01-01

    The 40Kh and 12KhN3A steels were used to compare the quality of the metal manufactured according to several variants of a single-slag process with the metal of a conventional melting technology. Investigation results show, that a single-slag process metal has higher sulfides and oxides contents as well as an increased anisotropy of mechanical properties while its tendency to flake formation is weaker due to a less degree of gas saturation. It is marked that anisotropy in the properties and a sulfide content may be decreased by out-of-furnace treatment of steels

  13. KH in Paraffin - KH(P): A Useful Base for Organic Synthesis

    Science.gov (United States)

    Taber, Douglass F.; Nelson, Christopher G.

    2011-01-01

    The preparation of KH as a one:one homogenate with paraffin, termed KH(P), is reported. KH(P), a solid at room temperature, is stable without special handling. On suspension in THF with a phosphonium salt, KH(P) rapidly generates the ylide. Wittig condensation with aromatic, aliphatic and α, β-unsaturated aldehydes proceeds with high Z-selectivity. KH(P) should be a generally useful base for organic synthesis. PMID:17081034

  14. Mechanical and fracture properties at impact loading of selected steels for nuclear power engineering

    International Nuclear Information System (INIS)

    Buchar, J.; Bilek, Z.

    1988-01-01

    The possibilities are briefly characterized of experimental research of mechanical and fracture properties of steels used in nuclear power engineering. Attention is paid to plastic deformation and the assessment of fracture formation during impact loading. The results are reported for steels 15Kh2MFA and 10GN2MFA. For steel 15Kh2MFA the effect was also studied of neutron radiation at different temperatures. From the theory developed for non-irradiated material 10GN2MFA, a prediction is made within the original model of the fracture stress value for steel 15Kh2MFA in both non-irradiated and irradiated states. The conclusion is arrived at that the existing methods of assessing steel properties at impact load allow obtaining knowledge of all significant effects during actual stress, this using only small specimens of the materials. (Z.M.). 4 figs., 8 refs

  15. Optimal control of conditions of deformation during rolling the bar alloy from alloy steel

    International Nuclear Information System (INIS)

    Inatovich, Yu.V.; Shilov, V.A.; Shvarts, D.L.; Kudelin, S.P.

    2001-01-01

    A complex of programs for determining the optimal gaps between rollers during rolling of simple merchant sections of alloy steels of a wide brand assortment (12KhN3A, Kh17N2, Kh18N10T) was elaborated. Experience in calculations made according to the programs suggests advisability of their use in the automated design systems for roller calibration and for adjustment of section mills [ru

  16. Effect of preliminary neutron irradiation on helium blistering of 0Kh16N15M3B steel

    International Nuclear Information System (INIS)

    Chernov, I.I.; Kalin, B.A.; Skorov, D.M.; Shishkin, G.N.; Ivanov, M.V.

    1982-01-01

    The method of electron microscopy has been applied to investigate the effect of preliminary neutron irradiation on the OKh16N15M3B steel blistering under irradiation by 20 keV helium ions with (1-10)x10 21 ion/m 2 doses at the temperature below 373 K. It is shown that neutron irradiation shifts critical doses of blister formation and intense scaling towards higher doses. But after the incubation period the erosion of steel preliminary neutron irradiated grows with the increase of helium ion dose above 7x10 21 ion/m 2 . Short-term heating of neutron irradiated samples during 15 min at 1173 K does not practically affect the beginning of intense scaling of the surface

  17. Development of production technology and investigation of quality for forged-welded turbine rotors of steel 25Kh2NVFA

    International Nuclear Information System (INIS)

    Borisov, I.A.; Merinov, G.N.; Slezkina, E.V.

    1997-01-01

    A study was made into mechanical properties and microstructure of turbine rotor components manufactured by forging and heat treated under various conditions. It is revealed that the optimal heat treatment of forgings must include double quenching with subsequent tempering at 630-640 deg C for 10-20 h. Forged and welded rotors should be tempered at 620-630 deg C for 50-100 h. Microscopic examination and mechanical tests showed that low alloy steel 25Kh2NMF can be successfully used for manufacturing rotors of high-, medium-and low-heat turbines

  18. Electron beam welding of flanges with tubular shafts of steel 40KhNMA

    International Nuclear Information System (INIS)

    Leskov, G.I.; Zhivaga, L.I.; Shipitsyn, B.N.; Savichev, R.V.

    1975-01-01

    The results are presented of elaborating the technological process for the electron beam welding of flanges with a tube of the 40KhNMA steel and of investigation into the quality of the welded joints. A welded piece has been fabricated conforming to the technology suggested observing the parameters worked-out in the following sequence: assembling the piece; pre-welding of the edges in some points; welding; high tempering; welds quality control; removal of the seam reinforcement inside of the tube and the weld root to the depth of 2 mm; quenching; tempering; welds quality control; finishing. The welds quality control consists in visual inspection, ultrasonic testing, magnetic flaw detection, as well as X-ray and metallographic analyses. The mechanical properties are studied on notched samples cut out of the welded joints. The test results have shown that the mechanical properties of the welded joints meet the requirements on the same level with the base metal

  19. Safety conditions of using structural steels under high temperature and pressures in hydrogen containing environment

    International Nuclear Information System (INIS)

    Asviyan, M.B.

    1984-01-01

    The method for establishing full-strength conditions was suggested on the base of results of creep-rupture test of tube samples under hydrogen pressure and according to permissible stresses in neutral medium. Applicability of the method was considered taking St3 and 12KhM steels as examples. It was shown that the use of suggested dependences and special efficiency factors enables to forecast endurance limit for the given steel grade and assigned partial hydrogen pressure without labour-intensive test conducting

  20. Properties of structural steels melted out of high-purity charge

    International Nuclear Information System (INIS)

    Marchenko, V.N.; Sergeeva, T.K.; Kondakova, N.K.; Morozov, V.P.; Madorskij, L.L.

    1993-01-01

    A comparative evaluation has been made of impurities, mechanical properties and hydrogen embirittlement parameters for steels type 40Kh and 40KhS produced by electrometallurgical method with the use of direct reduced charge (DR-steels) and melted in an open-hearth furnace. Investigation results have shown that 40Kh and 40KhS Dr-steels have more coarse austenitic grains and experience more complete transformation of martensite into ferritic-pearlitic mixture on tempering. Threshold stresses increase 2.5 times due to purity enhancement at the expense of application of direct reduced charge

  1. Determination of constant of chemical reaction rate in the process of steel treatment in the endothermal atmosphere

    International Nuclear Information System (INIS)

    Gyulikhandanov, E.L.; Kislenkov, V.V.

    1978-01-01

    The high-temperature method was applied to measuring a relative variation in the electrical resistance of a thin steel foil prepared from the 12KhN3A, 18Kh2N4VA, 20KhGNR, and 20Kh3MVF steels during its carburization and decarburization, and determined was the temperature dependence of the reaction rate of the interaction of the endothermal atmosphere of different compositions with the analloyed γ-Fe. A connection has been established between the reaction rate constant and the thermodynamic activity of carbon in the alloyed austenite at the temperature of about 925 deg C, corresponding to the cementation temperature. This provides the quantitative estimation of the above value for any alloyed steels and with the presence of numerical values of diffusion coefficients; this also enables one to carry out an accurate calculation of the distribution of carbon throughout the depth of a layer when effecting the cementation in the endothermal atmosphere

  2. The effect of thermoplastic treatment regimes on the microplastic strain of nitrogen-containing steel Kh21G10N7MBF

    International Nuclear Information System (INIS)

    Bannykh, O.A.; Blinov, V.M.; Kostina, M.V.; Grachev, S.V.; Mal'tseva, L.A.

    2005-01-01

    A study is made into the influence of a percentage reduction during cold rolling and subsequent holdings at heat on development of microplastic deformation when bending sheet specimens of stainless austenitic high-nitrogen steel Kh21G10N7MBF. It is revealed that a maximum value of apparent limit of elasticity (∼1800 MPa) is attained due to plastic deformation by rolling at 20 Deg C with a total percentage reduction of 60 % and subsequent aging at 500 Deg C for 1-4 h [ru

  3. Effect of austenitization conditions on kinetics of isothermal transformation of austenite of structural steels

    International Nuclear Information System (INIS)

    Konopleva, E.V.; Bayazitov, V.M.; Abramov, O.V.; Kozlova, A.G.

    1987-01-01

    Effect of austenization of kinetics of pearlite and bainite transformations for steels with different carbon content differing by alloying character and degree has been investigated. Austenization temperature increase is shown to leads to retardation of ferrite-pearlite transformation in low- and medium-carbon alloyed steels. Step-like holding in the region of austenite stable state (850, 950 deg) after high-temperature heating (1100 deg C) increases the rate of transformation partially recovering its kinetics and decomposition velocity after low-temperature heating in steels alloyed advantageously with carbide-forming elements (08Kh2G2F, 30Kh3) and does not affect kinetics in the 35Kh, 30KhGSN2A, 45N5 steels. Increase of heating temperature and growth of an austenite grain cause considerable acceleration of bainite transformation, increase of the temperaure of bainite transformation beginning and increase of the transformation amplitude in the 08Kh2G2F, 30Kh3 steels and affect weakly kinetics in steels with mixed alloying (30KhGSN2A) or low-alloy one (35Kh). The bainite transformation rate in the 45N5 steelite does not depend on austenization. The effect of additional acceleration of bainite transformation as a result holding after high-temperature heating in those steels, where activation of transformation occurs with increase of heating temperature

  4. Stationary potentials and corrosion of metals and steels in sodium and potassium chloride eutectic melts saturated with hydrogen chloride

    International Nuclear Information System (INIS)

    Belov, V.N.; Ershova, T.K.; Kochergin, V.P.

    1978-01-01

    Stationary potentials have been measured at 850 deg C and corrosion rates found gravimetrically for a number of metals and steels in the eutectic NaCl-KCl melt saturated with HCl. Periodic shifts of the stationary potentials towards positive values have been established in the Ti-V-Cr-Fe-Ni, Cu-Zr-Nb-Mo, Ag-Ta-W-Pt systems, with the corrosion rate of metals decreasing in them. The stationary potentials are shown to shift towards positive values in the series: st.08 KP, st.3, Kh17N2, Kh22N6T, Kh13NChG9, 1Kh18N10T, Kh17N13M2T, OKh17N16M3T, Kh23N18, Kh25N16G7, Kh23N28M3D3T, with corrosive resistance in this series increasing

  5. Choice of corrosion-resistant metal for fluotitanic acid

    International Nuclear Information System (INIS)

    Reingeverts, M.D.; Lapchenko, E.P.; Semenyuk, E.Y.

    1986-01-01

    The authors investigate the corrosion and anodic behavior of steels 12Kh18N10T, 08Kh21N6M2T, and 06KhN28MDT, nickel, and molybdenum in 10-40% naturally aerated solutions of H 2 TiF 6 at 20 and 50 degrees C. The authors found that in solutions of fluotitanic acid, as also in tetrafluoroboric and hydrofluoric acids, the most stable alloys are chromium-nickel-molybdenum alloy of type 06KhN28MDT and (for acid concentrations above 20%) copper-nickel-alloys of the monel metal type. Steels 12Kh18N10T and 08Kh21N6M2T can be used in acid concentrations of less than 10% and temperatures up to 20 degrees C with anodic protection

  6. Influence of quantity of non-martensite products of transformation on resistance to fracture of improving structural steel

    International Nuclear Information System (INIS)

    Gulyaev, A.P.; Golovanenko, Yu.S.; Zikeev, V.N.

    1978-01-01

    18KhNMFA, low-carbon, alloyed steel and 42KhMFA medium-carbon, alloyed steel have been examined. For the purpose of obtaining different structures in hardening the steel, different cooling rates, different temperatures and isothermal holding times are applied. The following has been shown: on tempering to the same hardness (HV 300), the presence of non-martensite structures in hardened state does not practically influence the standard mechanical properties of steel (sigmasub(B), sigmasub(0.2), delta, PSI). The resistance of steel to the brittle failure is enhanced by the uniform, fine-disperse distribution of the carbide phase in the structure of lower bainite (up to 80 % bainite in martensite for 42KhMF steel to be improved), as well as strongly fragmented packages of rack martensite-bainite (up to 50 % lower bainite in martensite of 18KhNMFA steel). The formation of the upper bainite in the structure of the hardened steels 18KhNMFA and 42KhMF results on tempering in the formation of coarse, non-uniform, branched carbide inclusions, and this, in its turn, leads to raising the cold-shortness threshold and to lowering the amount of work as required for propagation of a crack. The presence of ferritic-pearlitic structures in the structural steels hardened to martensite and bainite results in reducing the resistance of steel to the brittle failure; the presence of every 10 % ferritic-pearlitic component in martensite of the structural steels 18KhNMFA and 42KhMFA to be thermally improved, raises T 50 by 8 deg and 20 deg C, respectively

  7. Study of cast and thermo-mechanically strengthened chromium-nickel nitrogen-containing steel

    International Nuclear Information System (INIS)

    Prokoshkina, V.G.; Kaputkina, L.M.; Svyazhin, A.G.

    2000-01-01

    The effect of nitrogen on the structure and strength of corrosion-resistant chromium-nickel steels after thermal and thermomechanical treatment is studied. The 06Kh15N7AD and 07Kh15N7DAMB steels alloying by nitrogen was accomplished through the basic composition steels remelting in the molecular nitrogen atmosphere under the pressure of 0.1-2.5 MPa. The 02Kh15N5DAF and 05Kh15N5DAM steels ingots were obtained through melting in a plasma furnace under the nitrogen pressure of 0.4MPA. The high-temperature thermomechanical treatment (HTMT) was performed by rolling with preliminary blanks heating up to 1050 deg C and the rolling end temperature not below 950 deg C. It is shown, that the HTMT of the nitrogen-containing steels makes it possible to obtain strength characteristics by 1.5 times exceeding the properties of traditionally applicable corrosion-resistant steels, whereby sufficiently high plasticity of the nitrogen-containing steel is retained [ru

  8. Effect of neutron irradiation on the properties of the repair welds of the 15Kh2MFA steel

    International Nuclear Information System (INIS)

    Morozov, A.M.; Khachaturyants, L.V.

    1986-01-01

    The authors studied the effect of neutron irradiation on the tendency of the metal belonging to the heat affected zone of the weld toward brittle fracture (an increase in the critical temperature of brittleness). For comparison, the authors studied the radiation embrittlement of the original base metal (steel 15Kh2MFA) subjected to the conventional heat treatment of the reactor frames consisting of hardening and high-temperature tempering. Along with these materials, the radiational embrittlement of the base metal in the rehardened condition without tempering was studied. It was concluded that the presence of the regions repaired according to this technology and located in the frame at the level of the reactor core does not pose the problem of decreased resistance to brittle fracture

  9. Coarsening of (Fe, Cr)23C6 carbide phase on the tempering of 14Kh17N2 chromium-nickel steel

    International Nuclear Information System (INIS)

    Psarev, V.I.

    2002-01-01

    Paper lists the results of computer analysis of distribution according to sizes (Fe, Cr) 23 C 6 microparticles resulting from 14Kh17N2 steel tempering under 700 Deg C. Data were obtained at the maximum beneficial magnification of a light microscope. The mentioned curves of distribution densities are characterized by more reliable run from most permissible sizes of dispersed particles. Application of general rules of distributions and of previously elaborated procedure to identify experimental histograms with theoretical distributions enables to derive valuable information on dynamics of coarsening of a disperse phase in this case, as well [ru

  10. On the adsorption-induced fatigue of structural steels in the presence of alcohols

    International Nuclear Information System (INIS)

    Loboiko, V.I.; Karpenko, G.V.; Vasilenko, I.I.

    1976-01-01

    The purpose of the work was to study he effect of anhydrous alcohols on the cyclic fatigue of steels in the absence of contact of the alcohol with atmospheric moisture during the testing process. A vacuum was created in the operating space and then the vacuum annealing was carried out in a bath with the sample and through metal vacuum connection the bath was filled with anhydrous alcohol. Studies were made on several construction steels (20Kh, 40Kh, 50Kh, and ShKh15); steels 40Kh, 50Kh, and ShKh15 were quenched from 840-860 0 C in oil and then tempered at 200 0 C (2 h), steel 20Kh was studied in the as-received state. It was shown that with increase in the carbon content of steel with a martensite structure, the decrease in strength in the presence of anhydrous alcohol was greater than in dry air. Experiments showed that anhydrous alcohol causes an adsorption decrease in the strength both of samples with preliminarily formed cracks and V-shaped stress concentrators and of smooth samples. The greatest adsorption effect of alcohols in our case, as in static fatigue, was observed in samples with cracks. A dependence was shown between the length of the carbon chain and the fatigue limit. This dependence indicates the monotone nature of the decrease in the fatigue limit with transfer from methyl to butyl and then to octyl alcohol

  11. Application of experiment planning during investigation of cementation process in solid carburizers

    International Nuclear Information System (INIS)

    Lisenkov, A.N.; Denisov, V.M.; Prigozhina, E.L.

    1981-01-01

    A mathematical model of cementation process in solid carburizirs is obtained, the most effective contents of carburizers are chosen. Specimens are produced out of St20, 12KhN3A, 40Kh13, KhVG steels. It is shown that specimens of St20 and 12KhN3A steels have the higher depth of cementated layer, specimens made of 40Kh13 and KhVG steels-the lower depth. It is shown that the quality of cementated layer structure at recommended regimes improved, cementated layer depth for low-carbon steels changed a little and for tool steels increased infficiently: for KhVG steel in 2-3 times for 40Kh13 steel in 1.5-2.5 times

  12. Influence of isothermal thermomechanical treatment on structure and properties of structural steels

    International Nuclear Information System (INIS)

    Smirnov, M.A.; Kaletin, A.Yu.; Schastlivthev, V.M.; Kaletina, Yu.V.

    1997-01-01

    A study is made into the structure and mechanical properties of steel 35KhGSA and 37KhN3A after isothermal hardening resulting in bainitic structure formation as well as after low-temperature thermomechanical treatment (LTTMT) combining the plastic deformation at the temperature of bainitic transformation and subsequent isothermal hardening. It is shown that LTTMT permits and essential enhancement of strength properties in steel 35KhGSA, high plasticity and impact strength being reserved. This is associated with bainitic structure refinement. In steel 37KhN3A the process of carbide formation takes place along with bainitic transformation, and LTTMT results in lesser strengthening. LTTMT is fount to not practically affect the tendency of structural steels to bainitic brittleness. This treatment promotes some shift of brittleness manifestation to lower temperatures

  13. Effect of heat treatment and rotor steels composition on hydrogen solubility

    International Nuclear Information System (INIS)

    Ivanov, A.I.; Samojlenko, L.V.; Gorovaya, O.N.; Najdovskij, A.G.; Bilik, I.; Kret, Ya.

    1988-01-01

    Measurements of equilibrium hydrogen adsorption in samples of 27KhN3MFA and 25Kh2NMFA steels were conducted. Carbide inclusions and doping additions, typical for rotor steels, don't produce noticeable effect on hydrogen solubility in

  14. Effect of elevated temperature on the composition, structure, and mechanical properties of diffusion chromized steel

    International Nuclear Information System (INIS)

    Osintsev, V.D.

    1986-01-01

    The author studies the effect of operating temperature for equipment in contact sections of sulfuric acid workshops on the structure and mechanical properties of the chromized coatings and core of chromized articles. The ferrite lattice spacing was determined in a DRON-0.5 diffractometer according to the line in copper K /sub alpha/ radiation exposure was carried out after layer-by-layer anodic etching of the coating in an aqueous solution. It was shown that diffusion chromizing may lead to a reduction in strength properties compared with those of unchromized steel. As a base for chromized articles intended for operation at temperatures up to 475 0 C it is desirable to use steels 09G2 or 09G25, or for operation at temperatures up to 540 0 C, steels 12KhM and 12MKh

  15. Fracture of ledeburitic steel during hot plastic deformation

    International Nuclear Information System (INIS)

    Nikitin, V.P.; Borisov, Yu.A.; Bulat, S.I.; Zajtsev, V.V.

    1977-01-01

    The mechanisms of the high-temperature failure of high-carbon chromium Kh6F1, Kh6T2 and Kh6VF steels and a possibility to avoid their overheating have been investigated. At 1190 deg C and over the failure occurs along boundaries of grains at points of formation of the initial portions of the liquid phase as carbides are dissolved. If after a holding at 1190-1210 deg C the steels are cooled to 1120-1150 deg C and held for a sufficiently long time, secondary carbides are formed in the eutectic areas and, if the steels are deformed, the discontinuities present a rounded shape. Holding of an overheated steel at 1120-1150 deg C ensures its satisfactory workability in rolling. By choosing adequate overheating and subsequent slight cooling conditions, it is possible not only to retain, but even to improve the plasticity of carbide high-carbon steels. The results of laboratory tests have been confirmed under industrial conditions

  16. Effect of smelting method on the austenite grain size and properties of heat-resisting pearlitic steel

    International Nuclear Information System (INIS)

    Balakhovskaya, M.B.; Khusainova, N.A.; Davlyatova, L.N.

    1975-01-01

    Influence of smelting method on austenite grain size and properties of refractory perlite steel were studied. An opportunity was found to increase the steel refractoriness without deteriorating its other properties. The steel 12Kh1MF of electric or common open-hearth smelting was used. The dependence of kinetics of austenite grain growth on the smelting method was studied in the temperature range 950 deg - 1200 deg C with 1 hour exposure. The grain size of austenite in steel is supposedly determined by aluminium nitrides and vanadium carbides. In tests of normalized (kept for 20 minutes at 950-980 deg C) and tempered (kept for 3 hours at 730 deg C) transverse (tangential) pipe cross-section samples the electric steel had higher impact viscosity than the open-hearth metal. At working temperatures (540 deg -580 deg C) the difference in viscosity has its minimum. Viscosity of both steels 12Kh1MF begins to sharply decrease from 20 deg C. However, electric steel has rather high viscosity even at - 40 deg C, while the open-hearth one becomes brittle as early as at - 20 deg C. Long-term strength tests at 580 deg C under stresses 10-14 kG/mm 2 show that the coarse-grain steel is more refractory, i.e. time till fracture of open-hearth steel samples is twice as long as that of electric steel samples

  17. Boron effect on fabrication properties and service behaviour of complex corrosion-resistant steels

    International Nuclear Information System (INIS)

    Gol'dshtejn, Ya.E.; Piskunova, A.I.; Shmatko, M.N.

    1978-01-01

    In order to determine the optimum boron admixtures for the improvement of the technological plasticity without the considerable reduction in the corrosion resistance of the complex alloy Cr-Ni-Mo steels, industrial heats of the 03KH16N15M3, 03KH17N14M3 and other steels, containing 0.0005-0.003% boron, have been researched. The plasticity, corrosion resistance and microstructure of certain steels have been determined. It is shown that small additions of boron enhance the technological plasticity during the ingot rolling. In order to prevent a sharp reduction in the corrosion resistance, the boron content should be confined to 0.0015% and the quenching temperature raised to 1,120-1,150 deg C. The positive effect of the quenching temperature increase is accounted for by the solution of the excess phases and by the reduction of the dislocation density in the near-the-boundary zones

  18. X-ray diffraction study of slags forming during corrosion resistant steel production

    International Nuclear Information System (INIS)

    Slavov, V.I.; Zadorozhnaya, V.N.; Shurygina, A.V.

    1990-01-01

    Using X-ray diffraction analysis slags, forming during corrosion-resistant 12Kh18N10T grade steel production by two flowsheets, are studied. Standard two-slag technology of steel production does not provide efficient disintegration of chromospinelides in slags, gives high steel contamination with respect to nonmetallic impurities, coarse structure and, as a consequence, presence of macrodefects on rolled products surface. One-slag steel melting technology with titanium alloying of the steel at vacuum causes fast removal of chromospinelides at the beginning of reduction period, promotes titanium absorption by the steel, refines nonmetallic inclusions, provides more fine structure and steel plasticity, removes surface defects

  19. Long-term behaviour of heat-resistant steels and high-temperature materials

    International Nuclear Information System (INIS)

    1987-01-01

    This book contains 10 lectures with the following subjects: On the effect of thermal pretreatment on the structure and creep behaviour of the alloy 800 H (V. Guttmann, J. Timm); Material properties of heat resistant ferritic and austenitic steels after cold forming (W. Bendick, H. Weber); Investigations for judging the working behaviour of components made of alloy 800 and alloy 617 under creep stress (H.J. Penkalla, F. Schubert); Creep behaviour of gas turbine materials in hot gas (K.H. Kloos et al.); Effect of small cold forming on the creep beahviour of gas turbine blades made of Nimonic 90 (K.H. Keienburg et al.); Investigations on creep fatigue alternating load strength of nickel alloys (G. Raule); Change of structure, creep fatigue behaviour and life of X20 Cr Mo V 12 1 (by G. Eggeler et al.); Investigations on thermal fatigue behaviour (K.H. Mayer et al.); Creep behaviour of similar welds of the steels 13 Cr Mo 4 4, 14 MoV 6 3, 10 Cr Mo 910 and GS-17 Cr Mo V 5 11 (K. Niel et al.); Determining the creep crack behaviour of heat resistant steels with samples of different geometry (K. Maile, R. Tscheuschner). (orig.,/MM) [de

  20. Joint formation of dissimilar steels in pressure welding with superposition of ultrasonic oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Surovtsev, A P; Golovanenko, S A; Sukhanov, V E; Kazantsev, V F

    1983-12-01

    Investigation results of kinetics and quality of carbon steel joints with the steel 12Kh18N10T, obtained by pressure welding with superposition of ultrasonic oscillations with the frequency 16.5-18.0 kHz are given. The effect of ultrasonic oscillations on the process of physical contact development of the surfaces welded, formation of microstructure and impact viscosity of the compound, is shown.

  1. 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

  2. Investigation of intergranular corrosion resistance of Cr16Ni25NMo6 steel

    International Nuclear Information System (INIS)

    Kamenev, Yu.B.; Nazarov, A.A.; Kuusk, L.V.; Majdeburova, T.F.

    1990-01-01

    The effect of 08Kh16N25AM6 steel susceptibility to intergranular corrosion on its intergranular cracking resistance in high-temperature water is investigated. In addition, the performed tests point to the susceptibility of sensibilized Kh16N25AM6 steel to intergranular corrosion in media simulating an agressive environment of power generation equipment; the latter requires a strict control over the resistance of weld joints of the above steel to intergranular corrosion. It is shown that Kh16N25AM6 type steel in sensibilized state is susceptible to intercrystalline corrosion cracking in high-temperature water which correlates with its susceptibility to intergranular corrosion established by AM GOST 6032-84 and potentiodynamic reactivation methods

  3. 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

  4. Effect of smelting method on the austenite grain size and properties of heat-resisting pearlitic steel

    Energy Technology Data Exchange (ETDEWEB)

    Balakhovskaya, M B; Khusainova, N A; Davlyatova, L N [Vsesoyuznyj Nauchno-Issledovatel' skij Teplotekhnicheskij Inst., Moscow (USSR)

    1975-12-01

    Influence of smelting method on austenite grain size and properties of refractory perlite steel were studied. An opportunity was found to increase the steel refractoriness without deteriorating its other properties. The steel 12Kh1MF of electric or common open-hearth smelting was used. The dependence of kinetics of austenite grain growth on the smelting method was studied in the temperature range 950 deg - 1200 deg C with 1 hour exposure. The grain size of austenite in steel is supposedly determined by aluminium nitrides and vanadium carbides. In tests of normalized (kept for 20 minutes at 950-980 deg C) and tempered (kept for 3 hours at 730 deg C) transverse (tangential) pipe cross-section samples the electric steel had higher impact viscosity than the open-hearth metal. At working temperatures (540 deg -580 deg C) the difference in viscosity has its minimum. Viscosity of both steels 12Kh1MF begins to sharply decrease from 20 deg C. However, electric steel has rather high viscosity even at /sup -/40 deg C, while the open-hearth one becomes brittle as early as at /sup -/20 deg C. Long-term strength tests at 580 deg C under stresses 10-14 kG/mm/sup 2/ show that the coarse-grain steel is more refractory, i.e. time till fracture of open-hearth steel samples is twice as long as that of electric steel samples.

  5. Damping capacity of unstable steels on chromium-nickel-manganese base

    Energy Technology Data Exchange (ETDEWEB)

    Kochkin, L.I.; Rudakov, A.A. (Kirovskij Politekhnicheskij Inst. (USSR))

    1982-02-01

    The paper deals with results of a study on the energy scattering in OKh13N3G8, 20Kh13N3G4 and 30Kh13N3G4 unstable steels. It is shown that the development of microplastic strains most easily occurs in low-carbon steel having a two-phase structure in the initial state. The proceeding of microplastic deformations in carbon unstable steels is limited by the interstitial atom effect on the dislocation movement. It is established that in OKh13N3G8 steel the martensite ..cap alpha --> gamma..- transformation begins under the cyclic stress amplitudes below the yield point of this steel. The steels studied possess a high vibrostrength.

  6. Welding wires for high-tensile steels

    International Nuclear Information System (INIS)

    Laz'ko, V.E.; Starova, L.L.; Koval'chuk, V.G.; Maksimovich, T.L.; Labzina, I.E.; Yadrov, V.M.

    1993-01-01

    Strength of welded joints in arc welding of high-tensile steels of mean and high thickness by welding wires is equal to approximately 1300 MPa in thermohardened state and approximately 600 MPa without heat treatment. Sv-15Kh2NMTsRA-VI (EhK44-VI) -Sv-30Kh2NMTsRA-VI (EkK47-VI) welding wires are suggested for welding of medium-carbon alloyed steels. These wires provide monotonous growth of ultimate strength of weld metal in 1250-1900 MPa range with increase of C content in heat-treated state

  7. Effect of preliminary heat treatment on phase transformations and properties of the Kh15N5D2T (VNS-2) steel

    International Nuclear Information System (INIS)

    Madyanov, S.A.; Voronenko, B.I.; Makhnev, E.S.

    1978-01-01

    It is shown that preliminary heat treatment has a significant effect on the α→γ transformation kinetics, the quantity of residual austenite, the grain size and mechanical properties of the Kh15N5D2T steel after final heat treatment. The preliminary heat treatment regimes leading to the increase of the quantity of residual austenite and to grain refining increase the work of crack propagation in the finally strengthened state. The optimum properties were obtained after threefold preliminary tempering for 1h at 650 deg C. An approximately constant relation of α- and γ-phases (approximately 50%) is observed at 625 deg C irrespective of the investigated regimes of preliminary heat treatment

  8. Wear resistance and structural changes in nitrogen-containing high-chromium martensitic steels under conditions of abrasive wear and sliding friction

    International Nuclear Information System (INIS)

    Makarov, A.V.; Korshunov, L.G.; Schastlivtsev, V.M.; Chernenko, N.L.

    1998-01-01

    Martensitic nitrogen-containing steels Kh17N2A0.14, Kh13A0.14, Kh14G4A0.22 as well as steel 20Kh13 were studied for their wear resistance under conditions of friction and abrasion. Metallography, X ray diffraction analysis and electron microscopy were used to investigate the structural changes taking place in a thin surface layer on wearing. It is shown that an increase of nitrogen content of 0.14 to 0.22% promotes an enhancement of steel resistance to abrasive and adhesive wear, especially after tempering in the range of 500-550 deg C. Typically, the nitrogen-containing steels exhibit lower resistance to various types of wear in comparison with the steels with high-carbon martensite due to their lower deformability under conditions of friction loading

  9. Structural features and properties of the laser-deposited nickel alloy layer on a KhV4F tool steel after heat treatment

    Science.gov (United States)

    Shcherbakov, V. S.; Dikova, Ts. D.; Stavrev, D. S.

    2017-07-01

    The study and application of the materials that are stable in the temperature range up to 1000°C are necessary to repair forming dies operating in this range. Nickel-based alloys can be used for this purpose. The structural state of a nickel alloy layer deposited onto a KhV4F tool steel and then heat treated is investigated. KhV4F tool steel (RF GOST) samples are subjected to laser deposition using a pulsed Nd:YAG laser. A nickel-based material (0.02C-73.8Ni-2.5Nb-19.5Cr-1.9Fe-2.8Mn) is employed for laser deposition. After laser deposition, the samples are subjected to heat treatment at 400°C for 5 h, 600°C for 1 h, 800°C for 1 h, and 1000°C for 1 h. The microstructure, the phase composition, and the microhardness of the deposited layer are studied. The structure of the initial deposited layer has relatively large grains (20-40 μm in size). The morphology is characterized by a cellular-dendritic structure in the transition zone. The following two structural constituents with a characteristic dendritic structure are revealed: a supersaturated nickel-based γ solid solution and a chromium-based bcc α solid solution. In the initial state and after heat treatment, the hardness of the deposited material (210-240 HV 0.1) is lower than the hardness of the base material (400-440 HV 0.1). Only after heat treatment at 600°C for 1 h, the hardness increases to 240-250 HV0.1. Structure heredity in the form of a dendritic morphology is observed at temperatures of 400, 600, and 800°C. The following sharp change in the structural state is detected upon heat treatment at 1000°C for 1 h: the dendritic morphology changes into a typical α + γ crystalline structure. The hardness of the base material decreases significantly to 160-180 HV 0.1. The low hardness of the deposited layer implies the use of the layer material in limited volume to repair the forming surfaces of dies and molds for die casting. However, the high ductility of the deposited layer of the nickel

  10. Damping capacity of unstable steels on chromium-nickel-manganese base

    International Nuclear Information System (INIS)

    Kochkin, L.I.; Rudakov, A.A.

    1982-01-01

    The paper deals with results of a study on the energy scattering in OKh13N3G8, 20Kh13N3G4 and 30Kh13N3G4 unstable steels. It is shown that the development of microplastic strains most easily occurs in low-carbon steel having a two-phase structure in the initial state. The proceeding of microplastic deformations in carbon unstable steels is limited by the interstitial atom effect on the dislocation movement. It is established that in OKh13N3G8 steel the martensite α→γ- transformation begins under the cyclic stress amplitudes below the yield point of this steel. The steels studied possess a high vibrostrength [ru

  11. On effect of some thermodeformation parameters of welding cycle on tendency of pearlitic heat-resisting steels to fracture in reheating

    International Nuclear Information System (INIS)

    Prokhorov, N.N.; Bardokin, E.V.

    1979-01-01

    Studied is the inclination of the 12Kh1MF, 15Kh3M1F and N18K9M5T steels subject to thermodeformation cycle imitating a welding one, to fracture in reheating. A hot-rolled metal then subject to the same thermal treatment was used. The imitation of thermodeformation cycle of the welding permitted to vary maximum heating temperatures, the period during which the metal is kept at temperatures higher than 1100 deg C, and the cooling rate of ajacent zone metal. It is shown that the curve of the dependence of deformation ability and the tendency to fracture at the reheating of adjacent zone metal on the rate of its cooling at welding is U-shaped. Deformation ability has its maximum value at the cooling rate of 30 deg c/s in the range 1300 to 1000 deg C

  12. Chemical heat treatment of low alloyed maraging steels

    Energy Technology Data Exchange (ETDEWEB)

    Malinov, L S; Korotich, I K [Zhdanovskij Metallurgicheskij Inst. (Ukrainian SSR)

    1979-09-01

    The investigation concerned the nitriding, cementation, chromizing, borating of economically alloyed maraging grade 04Kh2N5MFYu steel. The investigated methods of chemothermal treatment were found to considerably increase the hardness of the surface layer of the maraging steel. The high tempering of the grade 04Kh2N5MFYu cemented and hardened steel was found to produce secondary hardening. On chromizing, the diffusion layer is an alloyed ferrite which strengthens because of the dispersion hardening on ageing. The formation of the plastic low-carbon martensite at relatively small cooling rates greatly decreases the tendency of the boride layer to cracking.

  13. Optimum conditions for aging of stainless maraging steels

    International Nuclear Information System (INIS)

    Mironenko, P.A.; Krasnikova, S.I.; Drobot, A.V.

    1980-01-01

    Aging kinetics of two 0Kh11N10M2T type steels in which 3 % Mo (steel 1), and 3 % Mo and 11 % Co (steel 2) had been additionally introduced instead of titanium were investigated. Electron microscopy and X-ray methods were used. It was ascertained that the process of steel aging proceeded in 3 stages. Steel 2 was hardened more intensively during the aging, had a higher degree of hardness and strength after the aging, weakened more slowly if overaged than steel 1. The intermetallide hcp-phase Fe 2 Mo was the hardening phase on steels extended aging. Optimum combination of impact strength and strength was was achieved using two-stage aging: the first stage - maximum strength aging was achieved, the second stage - aging at minimum temperatures of two-phase α+γ region

  14. Corrosion-electrochemical behavior of metals in alkali solutions

    International Nuclear Information System (INIS)

    Levin, V.A.; Levina, E.Eh.

    1995-01-01

    Results of an investigation into corrosion-electrochemical behaviour of 12Kh18N10T, 10Kh17N13M2T, 08Kh21N6M2T and 15Kh25T steels, 06KhN28MDT and KhN78T alloys as well as NP-2 nickel in sodium, potassium and lithium hydroxide solutions at 95-180 deg C temperatures are considered. It is ascertained, that anode polarization curves of all metals irrespective of hydroxide nature, concentration, temperature, presence of chloride and chlorate additions, are of identic character. The movement of anode polarization curves in the direction of lower current of hydroxide type in NaOH-KOH-LiOH series, temperature and solution concentration reduction at other equal terms. 12 refs.; 6 figs

  15. On the ways of improving mechanical properties of boiler steels subject to hydrogen effect

    International Nuclear Information System (INIS)

    Tkachev, V.I.; Litvin, A.K.; Zvezdin, Yu.I.

    1975-01-01

    The effect of oxygen on the strength properties of boiler steels Kh15M2 and 48TS subjected to heat treatment and preliminary plastic deformation has been studied. It is shown that changes in the strength properties of the steel are determined by the heterogeneity of its structure. Treatment which contributes to homogenization of the metal structure increases the resistance of the steel to detrimental effect of hydrogen. Absorption of hydrogen during cathode polarization at various current densities is shown

  16. Microstructure of a high boron 9-12% chromium steel

    Energy Technology Data Exchange (ETDEWEB)

    Andren, H.O. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Applied Physics

    2008-07-01

    Additions of small amounts of boron (10-100 ppm) to 9-12% chromium steels are often made since they have been found to be beneficial for the creep strength up to and above 600 C. The effect of boron is to restrict the coarsening of M{sub 23}C{sub 6} precipitates during service. It was found that increasing the boron content from 9 to 40 ppm gave a decrease in coarsening constant at 600 C by a factor of 2. The present understanding of boron solution, non-equilibrium grain boundary segregation, incorporation into M{sub 23}C{sub 6}, and diffusion is reviewed in the paper. A very high boron addition (300 ppm) was made in the trial TAF steel already in the 1950'ies. The microstructure of a similar trial steel, FT3B, has been studied detail. In this steel large Mo, Cr, Fe and V containing metal borides are formed rather than the expected BN, with the crystal structure M{sub 2}B{sub 2}. Nitrogen is therefore still available for the formation of VN. Due to tempering at a low temperature (690 C) to a high strength (830 MPa), this steel contained a dense distribution of very small VN precipitates, 5-15 nm in size. A similar VN distribution is probably the cause of the still unsurpassed creep strength of the TAF steel. (orig.)

  17. Role of grain refinement in hardening of structural steels at preliminary thermomechanical treatment

    International Nuclear Information System (INIS)

    Bukhvalov, A.B.; Grigor'eva, E.V.; Davydova, L.S.; Degtyarev, M.V.; Levit, V.I.; Smirnova, N.A.; Smirnov, L.V.

    1981-01-01

    The hardening mechanism during preliminary thermomechanical treatment with deformation by cold rolling or hydroextrusion is studied on structural 37KhN3M1 and 38KhN3MFA steels. Specimens have been tested on static tension, impact strength and fracture toughness. It is shown that hydroextrusion application instead of rolling does not change the hardening effect of preliminary thermomechanical treatment (PTMT). It is established that the increase of preliminary deformation degree and the use of accelerated short term hardening heating provides a bett er grain refinement and the increase of PTMT hardening effect [ru

  18. Manufacture of rings of 08Kh18N10T sheet for internal structures of WWER type reactors

    International Nuclear Information System (INIS)

    Fojta, A.; Nitka, B.

    1984-01-01

    Technology is presented of the manufacture of rings for the jacket, shaft, core catcher and shaft bottom of WWER-440 reactors produced by Vitkovice Steel Works. The rings are manufactured from sheets of austenitic steel 08Kh18N10T. The materials and technology problems are discussed of sheet production, ring welding technology and annealing following welding. The plastic properties are assessed of the welded joints and problems are outlined of ring production for WWER-1000 reactors. (B.S.)

  19. Operational reliability of high pressure steam lines of pearlitic steels after 150-200 thousand h service

    International Nuclear Information System (INIS)

    Veksler, E.Ya.; Chajkovskij, V.M.; Osasyuk, V.V.

    1980-01-01

    Usage of both calculational and physical methods is recommended to estimate a service operating life of long-term working steam line materials. Application of these methods is demonstrated when studying steam line bends made of 12MKh and 12Kh1MF pearlitic steels. Good coincidence of results for the determination of residual durability of steam lines is obtained using these two methods [ru

  20. Parameter optimization for steel quenching by C02-laser irradiation

    International Nuclear Information System (INIS)

    Moryashchev, S.F.; Kislitsyn, A.A.; Kosyrev, F.K.

    1984-01-01

    The dependence of average absorption factor on maximal temperature of the article surface during quenching by CO 2 -laser irradiation was determined empirically. The calculations of depth of a hardening zone and process productivity in 40 Kh, 4Kh13 steels and Armco-iron with regard to this dependence were conducted

  1. Effect of heat treatment regime on structural lamination in ferritic-austenitic steels

    International Nuclear Information System (INIS)

    Sizov, R.A.; Zakharova, M.I.; Novikov, I.I.; Bannykh, O.A.

    1983-01-01

    The effect of preliminary thermal treatment on lamination and viscosity of EhP-53 and KO-3 steels after durable aging at the temperature of 350 is studied. It is shown that preliminary heat treatment considerably affects lamination processes in the result of aging of 0Kh18G8N2T steel. The lowest rate of lamination and higher impact strength after aging at 350 deg C for 4500 hours corresponds to the following heat treatment: 10 hour aging at 650 deg C with cooling in the air, then quenching in water from 950 deg C after aging for 30 min and the following tempering (650 deg C, 5 hours). Unlike the 0Kh18G8N2T steel, lamination parameters of steel 0Kh22N6T practically do not change after the application of heat treatment. Nevertherless, taking into account results of impact strength, it is advisable to have thermal treatment according to the regime: quenching in water at 950 deg C after aging for 30 min

  2. Tantalum-containing Z-phase in 12%Cr martensitic steels

    DEFF Research Database (Denmark)

    Danielsen, Hilmar Kjartansson; Hald, John

    2009-01-01

    Z-phases in tantalum-containing 12%Cr steels have been investigated. In 12%Cr steel without any Nb or V, the formation of CrTaN Z-phases was observed. In 12%Cr steel which also contained V, the Ta entered Z-phase as a minor element, Cr(V,Ta)N. The crystal structure of Cr(V,Ta)N seems to be identi......Z-phases in tantalum-containing 12%Cr steels have been investigated. In 12%Cr steel without any Nb or V, the formation of CrTaN Z-phases was observed. In 12%Cr steel which also contained V, the Ta entered Z-phase as a minor element, Cr(V,Ta)N. The crystal structure of Cr(V,Ta)N seems...

  3. Material physical properties of 12 chromium ferritic steel

    International Nuclear Information System (INIS)

    Ando, Masanori; Wakai, Takashi; Aoto, Kazumi

    2003-09-01

    High chromium ferritic steel is an attractive candidate for structural material of the next Fast Breeder Reactor, since both of thermal properties and high temperature strength of the steel are superior to those of conventional austenitic stainless steels. In this study, physical properties of 12Cr steels are measured and compared to those obtained in the previous studies to discuss about stochastic dispersions. The effect of measurement technique on Young's modulus and the influence of the specimen size on coefficient of thermal expansion are also investigated. The following conclusions are obtained. (1) Young's modulus of 12Cr steels obtained in this study tends to larger than those obtained in the previous studies especially in high temperature. Such a discrepancy is resulted from the difference in measurement technique. It was clarified that Young's modulus obtained by free vibration method is more adequate those obtained by the cantilever characteristic vibration method. Therefore, the authors recommend using the values obtained by free vibration method as Young's modulus of 12Cr steels. (2) Both instant and mean coefficient of thermal expansion of 12Cr steels obtained in this study is in a good agreement with those obtained in the previous studies. However, the obviously different values are obtained from the measurement by large size specimens. Such a discrepancy is resulted from heterogeneous during heating process of the specimens. Therefore, the authors recommend using the values obtained by φ4 x 20 mm specimens as instant and mean coefficient of thermal expansion of 12Cr steels. (3) Specific heat of 12Cr steels obtained in this study agree with those obtained in the previous studies with a few exceptions. (4)Thermal conductivity of 12Cr steels obtained in this study agree with those obtained in the previous studies. (5) It was confirmed that instant and mean coefficient of thermal expansion, density, specific heat and thermal conductivity of 12Cr steels

  4. Crustal Structure of Khövsgöl, Mongolia

    Science.gov (United States)

    Scott, A. M.; Meltzer, A.; Stachnik, J.; Russo, R.; Munkhuu, U.; Tsagaan, B.

    2017-12-01

    Mongolia is part of the Central Asian Orogenic Belt, an accretionary event that spanned 800 million years from the mid-Proterozoic to mid-Phanerozoic. As a result of the past collisional and rifting events, the modern Khövsgöl rift system of northern Mongolia contains a heterogeneous lithospheric structure. The current rift system has three parallel N-S trending basins that roughly align with terrane boundaries. Structures inherited during the accretionary events may be a factor influencing regional deformation. The forces that drive local deformation are not well understood, but varying processes have been proposed: far-field effects of India-Eurasian plate convergence, westward subduction of the Pacific plate, magmatic underplating at the base of the crust, mantle plume activity, and asthenospheric mantle convection. Determining the nature of crustal features within this poorly understood region may illuminate processes that control rifting within intracontinental settings. A network of 26 broadband seismic stations encompassing 200 square kilometers of the Khövsgöl rift system were deployed from August 2014 to June 2016. More than 2100 events were detected, and most earthquakes were concentrated near rift structures. Events between Busiin-Gol and Darkhad, the westernmost and central basins of the Khövsgöl rift system, are distributed within the crust. An active fault is outlined along the eastern border of the Darkhad basin. Khövsgöl earthquakes bound both sides of the rift. Along the northern border of Lake Khövsgöl, seismic events define a shallow active fault orthogonal to the basin. The largest event recorded within the network was a magnitude ml=5.2 located near the northeastern border of Lake Khövsgöl on 12-05-2014. The focal mechanism of this earthquake is predominantly strike-slip, but also includes an extensional component. This work focuses on earthquake relocation and calculating moment tensors and focal mechanisms of larger regional

  5. Estimation of the Ultimate Tensile Strength of Steel from Its HB and HV Hardness Numbers and Coercive Force

    Science.gov (United States)

    Sandomirskii, S. G.

    2017-11-01

    A formula is derived to accurately describe the tabulated relation between the Brinell ( HB) and Vickers ( HV) hardnesses of steel over the entire range of their possible variation. This formula and the formulas describing the relation between the HB hardness of chromium-molybdenum and chromium-nickel steels and their ultimate tensile strength σu are used to analyze the change in σu of 38KhNM steel upon quenching and tempering. The data that reveal a relation between σu of 38KhNM steel and its coercive force are obtained.

  6. Study of radiation damage of steels for light water pressure vessels at UJV

    International Nuclear Information System (INIS)

    Vacek, N.; Stoces, B.

    1980-01-01

    Preoperational determination of radiation resistance of pressure vessel steels is performed at accelerated neutron exposure in a test or materials research reactor. The results obtained at accelerated and operating exposure are not fully identical and surveillance bodies are therefore used manufactured from the pressure vessel material. Currently, the following steels are used for the manufacture of light water reactor pressure vessels: Mn-Mo-Ni (ASTM-A533-B, ASTM-A508), Cr-Mo-V (15Kh2M1FA). At UJV Rez, for irradiation Chanca-M probes imported from France are used featuring electric temperature control. Almost identical radiation embrittlement was measured for all three steels after irradiation with a neutron fluence of 3x10 23 n.m -2 at a temperature of 290 degC. (H.S.)

  7. Tendency of the 18-8 type corrosion-resistant steel to cracking in automatic building-up of copper and copper base alloys in argon

    International Nuclear Information System (INIS)

    Abramovich, V.R.; Andronik, V.A.

    1978-01-01

    Studied was the tendency of the 18-8 type corrosion-resistant steel to cracking during automatic building-up of copper and bronze in argon. The investigation was carried out on the 0kh18n10t steel in argon. It had been established, that the degree of copper penetration into the steel inceases with the increase in the time of the 0Kh18n10t steel contact with liquid copper. Liquid copper and copper base alloys have a detrimental effect on mechanical properties of the steel under external tensile load during intercontant. It is shown that in building-up of copper base alloys on the steel-0Kh18n10t, tendency of the steel to cracking decreases with increase in stiffness of a surfaced weld metal plate and with decrease in building-up energy per unit length. The causes of macrocracking in steel at building-up non-ferrous metals are explained. The technological procedures to avoid cracking are suggested

  8. Properties of cast Ti-stabilised stainless steel after long-term ageing

    International Nuclear Information System (INIS)

    Ehrnsten, U.; Karjalainen-Roikonen, P.; Nenonen, P.; Ahlstrand, R.; Hietanen, O.; Timofeev, B.T.; Bloomin, A.A.

    2000-01-01

    Mechanical properties and microstructure are studied and compared for two kinds of specimens of cast Ti-stabilized stainless steel 08Kh18N10T used for manufacturing of valves and pumps in nuclear power plants. One set of specimens represents the main gate valve material after 106000 h (∼ 12 years) operation at 270 deg C. The comparison is made with reference specimens in as-fabricated state. The results of impact tests, hardness measurements and microscopic examination show that 12 year operation gives rise to the shift of ductile-brittle transition temperature to higher values (from - 68 deg C - 103 deg C). The microstructure of both materials is similar. The microhardness of δ-ferrite in the steel after long-term operation is slightly higher [ru

  9. Effect of reactor irradiation on long-term strength and creep of 0Kh16N15M3B steel under plane stressed state

    International Nuclear Information System (INIS)

    Khristov, G.P.; Kosov, B.D.

    1982-01-01

    The paper deals with analysis of results of experimental studies in creep of the austenitic OKh16n15m3b steel with various size of initial-structure grain under conditions of high-intensity reactor irradiation and control tests. It is suggested to consider the material initial structure effect on intensity of minimum creep rates both under ordinary and intrareactor conditions of loading by means of the function grain size effect on the equivalent stress. It is shown that the criterial expression previously suggested by the authors is invariant to the type of stressed and structural states and relative to intensity of minimal creep rates. It is established that the creep rate of the irradiated steel may be calculated from dependence for nonirradiated steel using as an argument a certain reduced equivalent stress which is a function of the acting stress and irradiation parameter

  10. Corrosion resistance of chromium-nickel steel containing rare earths

    International Nuclear Information System (INIS)

    Asatiani, G.N.; Mandzhgaladze, S.N.; Tavadze, L.F.; Chuvatina, S.N.; Saginadze, D.I.

    1983-01-01

    Effect of additional out-of-furnace treatment with complex alloy (foundry alloy) calcite-silicon-magnesium-rare earth metal on corrosion resistance of the 03Kh18N20M3D3C3B steel has been studied. It is shown that introduction of low additions of rare earths improves its corrosion resistance improves its corrosion resistance in agressive media (in 70% - sulfuric acid) in the range of transition from active to passive state. Effect of additional introduction of rare earth metals is not considerable, if potential of steel corrosion is in the range of stable passive state (32% - sulfuric acid). Additional out-of-furnace treatment with complex foundry alloy, containing rare earth metals, provides a possibility to use a steel with a lower content of Cr, Ni, Mo, than in conventional acid-resistant steels in highly agressive media

  11. PENDIDIKAN KARAKTER MENURUT KH. WAHID HASYIM

    Directory of Open Access Journals (Sweden)

    Rangga Sa’adillah S. A. P.

    2015-11-01

    Full Text Available This library research examined two research questions. They are what thoughts of KH. Wahid Hasyim about the character education are and how the concept of character education by KH. Wahid Hasyim is relevant to the current condition of education in Indonesia. This study reveals two findings through an inductive analysis. The chief finding of this study is that there are eight characteristic values taught by KH.Wahid Hasyim including religious, tolerant, independent, democratic, patriotic, nasionalist, communicative, and keen on reading. Second, this study disclosed that the thought of character education by KH. Wahid Hasyim is in line with the goal of character education. He strove to build a multicultural national life, educate an intelligent civilization, build a noble character, encourage people to contribute to the development of human life, and develop the potential of having kind hearts, positive thoughts and good behavior as well as exemplary models. He also sought to generate enthusiasm of citizens to keep the peace, creativity, independence, and to be able to coexist with other nations in a harmony.

  12. Innovative Education and Science in Information Technologies: Experience of M.Ye. Zhukovsky National Aerospace University «KhAI»

    Directory of Open Access Journals (Sweden)

    Kryvtsov, V.S.

    2015-05-01

    Full Text Available Information technologies are among the most promising and fastest growing sectors in the world and Ukrainian industry. In the paper the authors share the experience of National Aerospace University «KhAI» in personnel education and training for the IT industry and the results of successful cooperation with IT companies. Innovative education programs, scientific and practical researches in information technologies, which are implementing in KhAI are also discussed.

  13. Investigation of thermal fatigue of chromium-molybdenum steels, used for calcining and agglomeration constructions

    International Nuclear Information System (INIS)

    Sinyavskij, D.P.; Gorkalo, A.P.

    1979-01-01

    The technique for investigating thermal fatigue of materials is described. The data on sample stress deformed state and current temperature values are taken from the local volume of the material studied. Results of investigating thermal fatigue of the 15KhMl and 20KhMl steels are presented

  14. 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...

  15. Z-phase in 9-12% Cr Steels

    DEFF Research Database (Denmark)

    Danielsen, Hilmar; Hald, John

    2004-01-01

    The complex nitride Z-phase, Cr(V,Nb)N, has recently been identified as a major cause for premature breakdown in creep strength of a number of new 9-12%Cr martensitic steels. A thermodynamic model of the Z-phase has been created based on the Thermo-Calc software. The model predicts the Z-phase to......The complex nitride Z-phase, Cr(V,Nb)N, has recently been identified as a major cause for premature breakdown in creep strength of a number of new 9-12%Cr martensitic steels. A thermodynamic model of the Z-phase has been created based on the Thermo-Calc software. The model predicts the Z......-phase to be stable in all of the new 9-12%Cr martensitic steels. This has generally been confirmed by the performed experiments. Z-phase precipitation seems to be a kinetic problem, and drivning force calculations using Thermo-Calc with the developed model have been used to predict steel compositions, which...

  16. Topic 1. Steels for light water reactor pressure vessels

    International Nuclear Information System (INIS)

    Brumovsky, M.; Brynda, J.; Kepka, M.; Barackova, L.; Vacek, M.; Havel, S.; Cukr, B.; Protiva, K.; Petrman, I.; Tvrdy, M.; Hyspecka, L.; Mazanec, K.; Kupca, L.; Brezina, M.

    1980-01-01

    Part 1 of the Proceedings consists of papers on the criteria for the selection and comparison of the properties of steel for pressure vessels and on the metallurgy of the said steels, the selection of suitable material for internal tubing systems, the manufacture of high-alloy steels for WWER components, the mechanical and metallurgical properties of steel 22K for WWER 440 pressure components, and of steel 10MnNi2Mo for the WWER primary coolant circuit, and the metallographic assessment of steel 0Kh18N10T. (J.P.)

  17. Relationships of quenching stresses to structural transformations in steel

    International Nuclear Information System (INIS)

    Loshkarev, V.E.

    1985-01-01

    Technique for accountancy of the effect of stresses on structural transformations in steel when solving problems of thermoplasticity is suggested. It is revealed on the basis of the conducted calculations that accountancy of interrelation of stressed and structural states of 20Kh2MF steel essentially affects forecasting of results of quenching

  18. Influence of chemical heterogeneity of solid solutions on brittleness in chromium steels

    International Nuclear Information System (INIS)

    Madyanov, S.A.; Sedov, V.K.; Apaev, B.A.

    1985-01-01

    The role of chemical heterogeneity of solid solutions in formation of mechanical properties of Kh09, Kh15, Kh20, Kh19N2G5T chromium steels has been investigated. It is established that besides the known regioA of chemical heterogeneity in the vicinity of 475 deg C exists a high-temperature region (1000-1050 deg C), where maximum heteroge=- neity of chromium distribution in solid solution, is observed. Both types of chemical heterogeneity cause essential hardening of alloys, which becomes apparent in abrupt change of capability to microplastic deformation The mechanism of occurrence of the given temper brittleness consists in carbon diffusion into microvolunes enriched in carbide-forming elements

  19. Comportamiento parabólico del crecimiento de capas boradas en los aceros Y8A y X12M // Parabolic behavior of boriding layers growth in Y8A and X12M steels

    Directory of Open Access Journals (Sweden)

    C. Figueroa Hernández

    1999-01-01

    Full Text Available Se determina la influencia que tienen los principales parámetros tecnológicos del borado en el crecimiento de las capas y secorrobora el cumplimiento de la ley parabólica para predecir este comportamiento en los aceros Y8A y X12M.El proceso de borado se aplica en una mezcla de carburo de silicio y bórax (70 y 30 % a la temperatura de 850, 900 y 950 oCdurante un tiempo de 2, 4 y 6 horas. Como variable dependiente se seleccionó la profundidad del recubrimiento, a partir de lacual se obtuvieron los coeficientes del crecimiento parabólico y la energía de activación en función de la temperatura, el tiempodel proceso y el tipo de acero.La caracterización metalográfica reveló la presencia de la fase Fe2BPalabras claves: Borado, recubrimiento superf icial , t ecnología de recubrimiento.__________________________________________________________________________AbstractIt was determined the influence of the main technological parameters of the boriding process, and a mathematical model thatallows to predict this conduct on the steels Y8A and X12M steels was obtained.The boriding process is applied in a mixture of silicon carbide and borax (70 and 30% at 850, 900 and 950 oC temperatureduring a period of time 2, 4 and 6 hours. As an independent variable the depth of the coat was selected.It was obtained the parabolic growth coefficients, and the activation energy according to temperature, time and the chemicalcomposition of steel.Metallografic analysis reveals the presence of Fe2B phase.Key words: Boriding process, superf icial coat , coat technology.

  20. Improving composition of protective coatings for steel casting

    International Nuclear Information System (INIS)

    Kuz'kina, N.N.; Pegov, V.G.; Bogatenkov, V.F.; Shub, L.G.; Raspopova, N.A.

    1983-01-01

    A radically new fuel-free slag-forming mixture used as protective coating for steel casting is introduced. The lack of combustible powders precludes explosion and fire Lazard in mixture preparation. Usage of the new mixture in stainless steel casting of Kh18N10T type permitted to improve the ingot surface quality and reduce spoilage from 1.16 to 0.66%

  1. Long-term Stability of 9- to 12 % Cr Steels

    DEFF Research Database (Denmark)

    Hald, John

    2004-01-01

    In the recent 25 years creep rupture strength of 9- to 12 %Cr steels for steam pipes and turbines has been doubled by development of new alloys. This development has formed a basis for improved efficiency of fossil fired steam power plants by introduction of advanced steam temperatures...... and pressures. Newly developed steam pipe steels are based on modifications of well-established steels like the X 20CrMoV12 1. Balanced addition of V, Nb and N to a 9Cr 1 Mo steel led to the Modified 9 Cr steel P 91. Addition of 1% W to a 9Cr 1 MoVNbN base composition led to steel E 911 and partial replacement...... of Mo with 1.8 % W combined with a slight amount of Boron led to steel P 92. The creep rupture strength of these new alloys are now secured with long-term tests up to 100,000 hours, which demonstrate improvements of 50% (P 91), 75 % (E 911) and 100 % (P 92) in strength compared to X 20CrMoV12 1....

  2. Austenite strengthening and softening during hot deformation

    International Nuclear Information System (INIS)

    Tushinskij, L.I.; Vlasov, V.S.; Kazimirova, I.E.; Tokarev, A.O.

    1981-01-01

    Processes of formation of austenite structure of 20 and 12Kh18N10T steels during hot deformation and postdeformation isothermal holdings have been investigated by the methods of analysis of curves of hot deformation, high-temperature metallography and light microscopy. Deformation has been exercised by extention in vacuum with average 4x10 -2 s -1 rate. Deformation temperatures of steel 20 are 930 and 1000 deg C, of steel 12Kh18N10T - 1100 deg C. It is stated that dynamic recrystallization takes place in both investigated steels during hot deformation. In the carbonic steel it is developed by shifting sections of high-angular boundaries, flow stress in this case remains constant. Recrystallization is developed by subgrain coalescence in austenite steel, that brings about preservation of increased defect density in recrystallized volumes. As a result strengthening of steel is continued up to fracture during the increase of the deformation degree. Postdeformation weakening of 12Kh18N10T steel is slowed down as compared with weakening of carbonic steel [ru

  3. Cooling intensification during quenching of power plant components - the way to increase reliability

    International Nuclear Information System (INIS)

    Borisov, I.A.

    1989-01-01

    To enchance the complex of mechanical properties and to increase operation time of large components of power facilities, regimes of accelerated cooling are developed. Results of heat treatment with accelerated cooling of turbine rotor of steel 26KhN3M2FAA, disks of turbine welded rotor of steel 20KhN2MFAA, components of steel 35KhN3MFA, are given. Special steels with carbon content less than 0.30% for details of power machine-building are developed

  4. Microchemistry of neutron irradiated 12%CrMoVNb martensitic steel

    International Nuclear Information System (INIS)

    Little, E.A.; Morgan, T.S.; Faulkner, R.G.

    1992-01-01

    Non-equilibrium solute segregation has been studied in a 12%CrMoVNb martensitic steel following fast reactor irradiation at 465 C and correlated with the development of M 6 X η-phase. Cr, Ni, Si, Mo, P and Mn are all shown to exhibit positive segregation to lath boundaries and are subsequently incorporated into M 6 X precipitates. The co-segregation of a combination of these elements which include P and Si, and possibly Cr or Mo, appears to promote M 6 X formation

  5. Effect of KH2PO4 on gene expression, morphological and biochemical characteristics of stevia rebaudiana Bertoni under in vitro conditions.

    Science.gov (United States)

    Kahrizi, D; Ghari, S M; Ghaheri, M; Fallah, F; Ghorbani, T; Beheshti Ale Agha, A; Kazemi, E; Ansarypour, Z

    2017-08-15

    Stevia rebaudiana is one of the most important biologically sourced and low-calorie sweeteners Bertoni that has a lot of steviol glycosides. Tissue culture is the best for propagation of stevia and micro nutrients can affect both morphological traits and steviol glycosides production. Therefore, the effect of different concentrations of KH2PO4on stevia growth factors and gene expression had been studied by tissue culture methods, RT-PCR and HPLC. According the results, bud numbers had increased significantly in MS + 0.034 mMKH2PO4 media and the highest measured length was seen in plants grown under MS + 0.034 mM KH2PO4 treatment. Also, the highest growth rate (1.396 mm/d) was observed in MS + 0.034 mMKH2PO4.The best concentration of KH2PO4 for expression of UGT74G1 was 0.00425mMand the best one for UGT76G1 expression was 0.017mM. Interestingly, the best media for both stevioside and rebaudioside A accumulation was 0.017mM KH2PO4containing media. There was positive correlation between the best media for gene expression and the best one for steviol glycosides production.

  6. Structural changes IN THE Kh20N45M4B nickel alloys and THE Kh16N15M3B steel due to helium ion bombardment

    International Nuclear Information System (INIS)

    Kalin, B.A.; Chernikov, U.N.; Chernov, I.I.; Kozhevnikov, O.A.; Shishkin, G.N.; Yakushin, V.L.

    1986-01-01

    Using transmission electron microscopy, x-ray structural analysis, and the thermal desorption techniques, the authors carried out a detailed study of the structural and phase changes, defect formation, and helium accumulation in the He + -bombarded 16-15 austenitic steels and 20-45 nickel alloys. Microstructure of the bombarded specimens was studied using the methods of transmission electron microscopy of thin foils in the EVM-100, and EM-301G electron microscopes. Results of x-ray studies on the bombarded specimens are presented. The conducted studies show that bombardment of structural materials with light ions can lead to significant structural damages and changes in the chemical and phase composition of the surface layer. The possible mechanisms of the changes in the chemical and phase composition include selective sputtering and radiation-induced accelerated diffusion of elements in the field of internal lateral stresses developing during the He + implantation process

  7. Effect of cyclic electron irradiation on mechanical properties of austenite steel

    International Nuclear Information System (INIS)

    Tsepelev, A.B.; Sadykhov, S.I.O.; Chernov, A.I.; Sevost'yanov, M.A.

    2006-01-01

    To check the supposition on the possibility of radiation-stimulated process enhancement under cyclic irradiation conditions an experimental investigation is carried out to elucidate the effect of the mode of irradiation (continuous or cyclic) on mechanical properties of chromium-manganese austenitic stainless steel type 10Kh12G20V. The effect of some radiation hardening is observed under cyclic irradiation, however, the data obtained cannot be considered as good evidence for the validity of proposed model of dynamic preference if the scatter in experimental data is taken into account [ru

  8. SAE 1045 steel/WC-Co/Ni-Cu-Ni/SAE 1045 steel joints prepared by dynamic diffusion bonding: Microelectrochemical studies in 0.6 M NaCl solution

    International Nuclear Information System (INIS)

    Andreatta, Francesco; Matesanz, Laura; Akita, Adriano H.; Paussa, Luca; Fedrizzi, Lorenzo; Fugivara, Cecilio S.; Gomez de Salazar, Jose M.; Benedetti, Assis V.

    2009-01-01

    Corrosion of SAE 1045 steel/WC-Co/Ni-Cu-Ni/SAE 1045 steel interfaces was investigated in 0.6 M NaCl solution using an electrochemical microcell, which enables local electrochemical characterization at the micrometer scale. Two pieces of steel, one with a WC-Co coating covered with Ni (12 μm) and Cu (5 μm) layers, and the other with a Ni (15 μm) layer, were welded by dynamic diffusion bonding. A WC-Co coating was applied to the steel by the high velocity oxygen-fuel process, and Ni-Cu and Ni layers by electroplating. Polarization curves were recorded using an electrochemical microcell. Different regions of welded samples were investigated, including steel, cermet coating, and steel/cermet and steel/Ni-Cu-Ni/cermet interfaces. Optical and electronic microscopes were employed to study the corroded regions. Potentiodynamic polarization curves obtained using the microcell revealed that the base metal was more susceptible to corrosion than the cermet. In addition, cermet steel/cermet and steel/Ni-Cu-Ni/cermet joints exhibited different breakdown potentials. Steel was strongly corroded in the regions adjacent to the interfaces, while the cermet was less corroded. Iron oxides/hydroxides and chloride salts were the main corrosion products of steel. After removal of the superficial layer of corrosion products, iron oxides were mainly observed. Chloride ions were detected mainly on a copper-enriched layer placed between two Ni-enriched layers.

  9. Fouling and biocorrosion of a high-alloy steel in the Golden Horn bay

    International Nuclear Information System (INIS)

    Koryakova, M.D.; Nikitin, V.M.; Suponina, A.P.; Kharchenko, U.V.; Zvyagintsev, A.Yu.

    2002-01-01

    The studies on the effect of contamination of the Golden Horn bay waters (the Peter the Great Bay in the Japanese Sea) on formation of the community of the bacterio- and macrofouling and corrosion resistance of the Kh18N10T high-alloy steel are continued. The dissolved and chemically absorbed oxygen, pH, saprophytes, oil-oxidizing, sulfate-reducing bacteria and heavy metals are among the medium indicators, characterizing the level of pollution of the regions of the samples testing. It is shown, that the obtained experimental data extend our understanding of the dependent effect of three factors: the sea medium → fouling → corrosion resistance of the Kh18N10T high-alloy steel [ru

  10. Strength of low-carbon rotor steel

    International Nuclear Information System (INIS)

    Voropaev, V.I.; Filimonov, O.V.; Borisov, I.A.

    1988-01-01

    The results of studying the effect of chemical composition and thermal treatment regimes on the structural strength of steels of the 25KhN3MFA type are presented. It is shown that alloying with niobium from 0.01 to 0.08% steels with the increased nickel content (4.2-4.5%) contributes to the increase of structural strength and reduction of semibrittleness temperature. To obtain high values of strength and plastic properties cooling with the rate of 10 3 -10 5 K/hr is recommended

  11. Friction stir welding of F/M ODS steel plug and F/M steel tube

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Suk Hoon, E-mail: shkang77@kaeri.re.kr [Nuclear Materials Division, Korea Atomic Energy Research Institute (Korea, Republic of); Vasudevan, M. [Materials Technology Division, Indira Gandhi Centre for Atomic Research, Kalpakkam (India); Noh, Sanghoon; Jin, Hyun Ju; Jang, Jinsung; Kim, Tae Kyu [Nuclear Materials Division, Korea Atomic Energy Research Institute (Korea, Republic of)

    2016-11-01

    Highlights: • Friction stir welding (FSW) was used for joining of oxide dispersion strengthened (ODS) steel plug and F/M steel tube. • The curvature and smaller thickness of tube was the major limitation for applying FSW method, it was solved using specially designed jig. • Considerable hardening occurs in the joint because the cooling rate was sufficient to reproduce a martensitic microstructure. • The measured hoop strength of the FSWed joint was 70–90 MPa, the value was at around 70% of the tube. - Abstract: Friction stir welding (FSW) was used for joining of oxide dispersion strengthened (ODS) steel plug and F/M steel tube. The dimensions of the tube included outer diameter of 7 mm, wall thickness of 0.5 mm. The objective was to find suitable process variables for gaining enough frictional heat from those thin and curved pieces. A specially designed jig was used for stabilization and slow rotation of tube during FSW. Additionally, the plug was designed to overlap the tube. Inconel 718 was used as FSW tool, the diameter was 3.5 mm. The adequate rotation speed of the tool and jig were 1200 rpm and 1.5 rpm, respectively. The joining was successfully accomplished using above combination, showing a good possibility. The hoop stress tests of joint were conducted by blowing Ar gas into the tube, the flow rate of gas was 10 MPa/min. The measured hoop stress was 70–90 MPa, the value was at around 70% of the tube.

  12. Friction stir welding of F/M ODS steel plug and F/M steel tube

    International Nuclear Information System (INIS)

    Kang, Suk Hoon; Vasudevan, M.; Noh, Sanghoon; Jin, Hyun Ju; Jang, Jinsung; Kim, Tae Kyu

    2016-01-01

    Highlights: • Friction stir welding (FSW) was used for joining of oxide dispersion strengthened (ODS) steel plug and F/M steel tube. • The curvature and smaller thickness of tube was the major limitation for applying FSW method, it was solved using specially designed jig. • Considerable hardening occurs in the joint because the cooling rate was sufficient to reproduce a martensitic microstructure. • The measured hoop strength of the FSWed joint was 70–90 MPa, the value was at around 70% of the tube. - Abstract: Friction stir welding (FSW) was used for joining of oxide dispersion strengthened (ODS) steel plug and F/M steel tube. The dimensions of the tube included outer diameter of 7 mm, wall thickness of 0.5 mm. The objective was to find suitable process variables for gaining enough frictional heat from those thin and curved pieces. A specially designed jig was used for stabilization and slow rotation of tube during FSW. Additionally, the plug was designed to overlap the tube. Inconel 718 was used as FSW tool, the diameter was 3.5 mm. The adequate rotation speed of the tool and jig were 1200 rpm and 1.5 rpm, respectively. The joining was successfully accomplished using above combination, showing a good possibility. The hoop stress tests of joint were conducted by blowing Ar gas into the tube, the flow rate of gas was 10 MPa/min. The measured hoop stress was 70–90 MPa, the value was at around 70% of the tube.

  13. Mutation and crystallization of the first KH domain of human polycytosine-binding protein 1 (PCBP1) in complex with DNA

    International Nuclear Information System (INIS)

    Yoga, Yano M. K.; Traore, Daouda A. K.; Wilce, Jacqueline A.; Wilce, Matthew C. J.

    2011-01-01

    The successful preparation of a mutant KH domain representing the first KH domain of PCBP1 and its crystallization in complex with a C-rich DNA are reported. This structure is anticipated to provide high-resolution information that will allow better understanding of the basis of cytosine specificity by PCBPs. Polycytosine-binding proteins (PCBPs) are triple KH-domain proteins that play an important role in the regulation of translation of eukaryotic mRNA. They are also utilized by viral RNA and have been shown to interact with ssDNA. Underlying their function is the specific recognition of C-rich nucleotides by their KH domains. However, the structural basis of this recognition is only partially understood. Here, the preparation of a His-tagged KH domain is described, representing the first domain of PCBP1 that incorporates a C54S mutation as well as the addition of a C-terminal tryptophan. This construct has facilitated the preparation of highly diffracting crystals in complex with C-rich DNA (sequence ACCCCA). Crystals of the KH1–DNA complex were grown using the hanging-drop vapour-diffusion method in 0.1 M phosphate–citrate pH 4.2, 40%(v/v) PEG 300. X-ray diffraction data were collected to 1.77 Å resolution and the diffraction was consistent with space group P2 1 , with unit-cell parameters a = 38.59, b = 111.88, c = 43.42 Å, α = γ = 90.0, β = 93.37°. The structure of the KH1–DNA complex will further our insight into the basis of cytosine specificity by PCBPs

  14. Properties of 40N3M powder structural steel

    International Nuclear Information System (INIS)

    Moskvina, T.P.; Gulyaev, A.P.; Gulyaev, I.A.; Byakov, S.V.; Melent'ev, I.V.; Morgun, G.N.

    1984-01-01

    Effect of the fabrication technique of compact slabs made of the 40N3M powder structural steel on mechanical properties with determination of a cold brittleness threshold was studied. It is established that after a thermal treatment at a density close to 100% a powder steel is sufficiently close to steel, rolled of an ingot, but is second in reference to steel in its ductility and impact strength. Properties of powder steel obtained by the method of dynamic hot forming (DHF) and hot extrusion are practically equal, but the first method has definite advantages as it allows to obtain details with a definitive form. The above investigation permits to recommend an application of the 40N3M powder steel fabricated by the DHF methods. The optimum thermal treatment course is: quenching+high annealing

  15. Methods for protection of high-strength welded stainless steel from corrosion cracking

    International Nuclear Information System (INIS)

    Lashchevskij, V.B.; Gurvich, L.Ya.; Batrakov, V.P.; Kozheurova, N.S.; Molotova, V.A.; Shvarts, M.M.

    1978-01-01

    The efficiency of protection from corrosion cracking under a bending stress of 100 kgf/mm 2 in a salt mist and in a sulphur dioxide atmosphere, of welded joints of steel 08Kh15N5D2T with metallizing, galvanic and varnish coatings and lubricants, and of steel 1Kh15N4AM3 with sealing compounds has been investigated. Metallization of welded joints with aluminium and zinc efficiently increases corrosion resistance in a salt mist. Galvanic coatings of Cd, Zn, and Cr increase the time to cracking in a salt mist from 2-3 to 60-80 days. The protective properties of varnishes under the effect of a salt mist decrease in the following sequence: epoxy-polyamide enamel EP-140, acrylic enamel C-38, silicone enamels KO-834, KO-811, and KO-814. In an atmosphere containing SO 2 0.15 vol.% at 100% relative humidity, the varnishes investigated, with the exception of the inhibited coating XC-596, show lower protective properties than in a salt mist. The high efficiency of protection from corrosion cracking in a salt mist of slots of steel 1Kh15N4AM3 when using organic sealing compounds U4-21 and U5-21, and also slushing lubricants and oils PVK, TsIATIM-201, K17, and AMS3 was established

  16. Smelting of high-quality boiler steel in large-load arc furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Kablukovskij, A F; Breus, V M; Tyurin, E I; Khristich, V D; Dumchev, Ya P [Tsentral' nyj Nauchno-Issledovatel' skij Inst. Chernoj Metallurgii, Moscow (USSR)

    1975-02-01

    High-grade steel can be obtained in large-capacity furnaces if the smelting technology used takes account of the size of the aggregates, the course of the metal fusion process, interaction with slag, furnace atmosphere, reducing agents, and other process characteristics. 12Kh1MF boiler steel smelted in a 100-ton electric arc furnace by an oxidizing process with oxygen bath blow and cast by the siphon method into 6.5-ton ingots using a slag-forming mixture (240 mm diameter billets and 219 to 245 mm diameter tubes) is satisfactory with regard to macro and microstructure, oxygen and nonmetallic oxide inclusion content, and mechanical properties. The stress rupture strength of 10/sup 5/ h at 570/sup 0/C is similar to that of open-hearth steel. Sulfides larger than a 3.5 spheroid have been detected in it. The nitrogen content of the electric steel is 0.0090 to 0.0120%, which is somewhat greater than usual in open-hearth metal. Of the oxygen inclusions in the steel, spinel-alumina predominates. Large inclusions were represented mainly by brittle silicates which appeared to be of exogenous origin.

  17. Investigation into mechanical properties of joints of heterogeneous materials brazed with high-temperature solders

    International Nuclear Information System (INIS)

    Lomenko, V.I.; Merkushev, V.P.; Borodina, L.M.; Sycheva, T.S.; Tokhtina, O.A.; Frolov, N.N.

    1988-01-01

    Mechanical properties of copper joints with copper, 12Kh18M10T steel and KhD50 composite obtained by vacuum brazing by copper-titanium solder as compared with properties of joints brazed by PSr 72 and PMFOTsr 6-4-0.03 solders in hydrogen are studied. Dependences of joints strength on temperature of contact - reactive vacuum brazing are obtained. Possible applications of joints of dissimilar materials in electrovacuum devices subjected to the effect of dynamic loadings are established

  18. A new 12% chromium steel strengthened by Z-phase precipitates

    DEFF Research Database (Denmark)

    Liu, Fang; Rashidi, Masoud; Johansson, Lennart

    2016-01-01

    In order to increase the corrosion resistance and simultaneously maintain the creep resistance of 9-12% Cr steels at 650 degrees C, a new alloy design concept was proposed, using thermodynamically stable Z-phase (CrTaN) precipitates to strengthen the steel. A new trial Z-phase strengthened 12% Cr...

  19. Microstructure and Mechanical Property of 12Cr Oxide Dispersion Strengthened Steel

    Science.gov (United States)

    Xu, Haijian; Lu, Zheng; Jia, Chunyan; Gao, Hao; Liu, Chunming

    2016-03-01

    Nanostructured oxide dispersion strengthened (ODS) steels with nominal compositions (wt%): Fe-12Cr-2W-0.3Ti-0.3Y2O3 were produced by mechanical alloying and hot isostatic pressing. The microstructure was characterized by means of electron microscopy (EBSD, TEM and HRTEM) and the hardness and the tensile properties at different temperatures were measured. The results showed that the ultimate tensile strength of the fabricated 12Cr-ODS steel reached nearly 1,100 MPa at room temperature and maintained around 340 MPa at 700°C. Nano-oxide particles with size ranging from several nm to 30 nm and the number density was 3.6 × 1020/m3 were observed by TEM. Following heat treatment, including normalizing at 1,100°C for 1 h and tempering at 750°C for 2 h, the average grain size was a little decreased. The number of nano-oxide particles increased and the number density was 8.9 × 1020/m3. Specimens showed much higher ductility and there was a slight increase of ultimate tensile strength and Vickers hardness at the same time.

  20. Fatigue resistance of Cr-Ni-Mo-V steel

    International Nuclear Information System (INIS)

    Naumchenkov, N.E.; Filimonova, O.V.; Borisov, I.A.

    1985-01-01

    A study was made on the effect of additional alloying (Ni, Ni+Co), stress concentration, surface plastic strain on fatigue resistance of rotor steel of Cr-Ni-Mo-V-composition. It is shown that the steel with decreased carbon content possesses high complex of mechanical properties. Fatigue characteristics are not inferior to similar characteristics of steels of 25KhN3MFA type. Additional alloying of the steel containing 0.11...0.17% C and 4.5...4.7% N:, with niobium separately or niobium and cobalt in combination enabled to improve fatigue resistance of samles up to 25%. Strengthening of stress concentration zones by surface plastic strain is recommended for improving rotor suppporting 'nower under cyclic loading

  1. Boron content effect on the high-temperature plasticity of corrosion resistant low-carbon austenite type steels

    International Nuclear Information System (INIS)

    Gol'dshtejn, Ya.E.; Shmatko, M.N.; Chuvatina, S.N.

    1976-01-01

    With the concept that the state of grain and subgrain boundaries influences the hot plasticity of corrosion resistant steel as a starting point, the study was undertaken of the effect of boron microalloying up on the intergranular strength and of the action boron exerts upon the distribution (redistribution) of other phases present in austenitic 03Kh16N14M3 steels. An electron microscope study of the composition of redundant phases and that of the fine structure of steel have shown the effect of small additions of boron upon the hot plasticity of steel to be linked directly to its influence upon austenite disintegration and the precipitation along the boundaries of crystals of redundant phases in the course of hot plastic deformation. The action of boron upon the process plasticity of steel depends on the temperature and the rate of deformation which govern the kinetics of the precipitation of the redundant phases

  2. The effect of alloying and treatment on martensite transformation during deformation in Fe-Cr-Mn steels with unstable austenite

    International Nuclear Information System (INIS)

    Malinov, L.S.; Konop, V.I.; Sokolov, K.N.

    1977-01-01

    The effect is studied of alloying with chromium (6-10%), silicon (1-2%), molybdenum (1-3%), and copper (2%), the heat treatment conditions, and the deformation conditions, or the martensitic transformation and mechanical properties of Fe-Cr-Mn steels of the transitional class based on 0G8AM2S. It is shown that appropriate alloying and treatment, taking into account the degree of stability of the austenite, can ensure a complex of high mechanical properties of the steels investigated. For instance, the treatment of steel 0Kh10AG8MD2S by the technique: hardening+ 40% deformation at 400 deg C + 10% deformation at room temperature has yielded the following mechanical properties: sigmasub(B)=150 kgf/mm 2 , sigmasub(T)=110 kgf/mm 2 , sigma=18%, psi=32%

  3. Influence of heating temperature on bainite transformation proceeding in chromium-nickel-molybdenum steels

    International Nuclear Information System (INIS)

    Kaletin, Yu.M.; Kaletin, A.Yu.

    1983-01-01

    The purpose of the present paper is to investigate the effect of heating and cooling from austenization temperature on development of bainite transformation in 37KhN3MFA and 18Kh2N4MA structural alloyed steels. The metallographical analysis of specimens has revealed that first crystals of bainite under slow heating up to 770-790 deg C appear at the temperature of about 500 deg C and at 475 deg C there has been much bainite over the whole cross section of the specimen. It is revealed that an increase of heating temperature and cooling rate replace the starting point of bainite transformation upwards. The strongest displacement of the point Bsub(S) into hogh-temperature range takes place after heating steel with the initial bainite structure in intercritical temperature range

  4. The influence of heating rate on reheat-cracking in a commercial 2 1/4Cr1Mo steel

    International Nuclear Information System (INIS)

    Hippsley, C.A.

    1983-03-01

    The effects of elevated heating rate on stress-relief cracking in a commercial 2 1/4 Cr1Mo steel have been investigated. A SEN bend-specimen stress-relaxation test was used to assess reheat cracking susceptibility and fracture mechanisms for an initial post-weld heating rate of 1000 Kh - 1 . Two factors controlling the influence of heating rate on the final severity of cracking were identified, i.e. the rate of stress-relaxation with respect to temperature, and the time available for crack-growth. The factors were found to counteract each other, but in the case of commercial 2 1/4 Cr1Mo steel, the crack-growth factor outweighed the relaxation factor, resulting in a reduction in the propensity to stress-relief cracking at the elevated heating rate. However, by reference to the results of a separate investigation concerning A508/2 MnMoNiCr steel it was demonstrated that the balance between these two factors may be reversed in other alloy systems, with the consequence that reheat cracking is exacerbated by increasing the initial heating rate. A computer model was addressed to the stress-relaxation test conditions using data from the commercial 2 1/4 Cr1Mo steel. The model predictions exhibited reasonable agreement with experimental test results for both 100 Kh - 1 and 1000 Kh - 1 heating rates. (author)

  5. Room and elevated temperature Mechanical Behavior of 9-12% Cr Steels

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, Omer N.; Hawk, Jeffrey A.; Schrems, Karol K.

    2005-02-01

    The mechanical properties of medium Cr steels used in fossil fired power plants are very good because of their excellent high temperature microstructural stability. However, as the desire to increase the operating temperature (>650C) of the plant goes up, the need for steels that maintain their strength at these temperatures also increases. The mechanical properties of three medium Cr steels (0.08C-(9-12)Cr-1.2Ni-0.7Mo-3.0Cu-3.0Co-0.5Ti) were investigated through hardness, hot hardness and tensile measurements. The strength of the 9-12%Cr steels at room temperature after long-term isothermal aging (750C; 1000 hours) compares favorably with that of other power plant steels (e.g., P91). In addition, the elevated temperature strength and hot hardness also behave similarly. The mechanical behavior will be discussed in terms of the strength, elongation and tensile fracture characteristics.

  6. Quality control of chemical heat treatment by the fractography method

    International Nuclear Information System (INIS)

    Tamarina, A.M.; Parygin, V.A.; Karpov, V.N.

    1978-01-01

    A fractographic investigation is carried out of fracture of a nitrided layer of 38KhMYuA steel and of cemented and cyanided layers of 12KhM3A steel. It is established that a fracture of the nitrided layer consists of three zones of crystalline facets: 1) a surface zone of fine crystalline facets located in a single plane and having the appearance of a white band (Σ-phase zone); 2) zone of acicular facets whose presence is due to the break-down of the carbonitride phase; 3) zone of large facets of boundary breakdown. The fractures of cemented and cyanided samples consist of multiple fine facets of multi-face shapes. It has been found that the depth and the microstructure of a diffusion layer in steel after chemothermal processing can be most rapidly and objectively evaluated by the fractographic method

  7. Design of the WWER-440 pressurizer

    International Nuclear Information System (INIS)

    Bednarek, L.

    1978-01-01

    The main specifications are presented of a pressurizer for the WWER-440 reactor as are factors securing operating reliability and the required life of the equipment. Ferritic-pearlite steel 22K is the basic material for the manufacture of the shell, support and couplings. The internal parts and the heads are manufactured from the 08KH18N10T chromium-nickel austenitic steel, the bolts and nuts of manholes from chromium-molybdenum steels 25KH1MF and 25KH2MFA. Quality testing of basic materials and quality control during the process of manufacture are briefly described. (Z.M.)

  8. Water vapor pressure over molten KH2PO4 and demonstration of water electrolysis at ∼300ºC

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Nikiforov, Aleksey Valerievich; Petrushina, Irina

    2016-01-01

    A new potentially high-efficiency electrolyte for water electrolysis: molten monobasic potassium phosphate, KH2PO4 or KDP has been investigated at temperatures ∼275–325 °C. At these temperatures, KH2PO4 was found to dissociate into H2O gas in equilibrium with a melt mixture of KH2PO4—K2H2P2O7—KPO3...... of water and methane or hydrogen to be 0.40 ± 0.02 or 1.2 ± 0.03. At equilibrium the vapor pressure was much lower than the vapor pressure above liquid water at the same temperature. Electrolysis was realized by passing current through closed ampoules (vacuum sealed quartz glass electrolysis cells...... with platinum electrodes and the electrolyte melt). The formation of mixtures of hydrogen and oxygen gases as well as the water vapor was detected by Raman spectroscopy. In this way it was demonstrated that water is present in the new electrolyte: molten KH2PO4 can be split by electrolysis via the reaction 2H2O...

  9. Microstructure and elevated temperature stability of 9-12% Cr steels

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, Omer N.; Hawk, Jeffrey A.

    2005-02-01

    Medium Cr steels have been used in fossil fired power plants for many years because of their excellent high temperature stability and mechanical properties. As the desire to increase the efficiency of power plants continues, the operating temperature (>650C) continues to go up. Currently available low and medium Cr containing steels will not withstand the new operating temperature and must be reassessed in terms of their solid-solution and precipitation strengthening schemes. Three medium Cr steels were developed to investigate high temperature alloy strengthening strategies: 0.08C-(9-12)Cr-1.2Ni-0.7Mo-3.0Cu-3.0Co-0.5Ti. The microstructure of the alloy will be described in the as-cast and thermo-mechanically worked states. In addition, the effect on microstructure from long-term high temperature exposure will also be discussed. Finally, the overall stability of these steels will be compared against currently available power plant steels.

  10. Investigation of fretting corrosion of vacuum-chrome-plated vt3-1 titanium alloy in pair with unprotected vt3-1 alloy and 40khnma steel

    International Nuclear Information System (INIS)

    Rojkh, I.L.; Koltunova, L.N.; Vejtsman, M.G.; Birman, Ya.N.; Skosarev, A.V.; Kogan, I.S.

    1978-01-01

    The character of destruction of contacting surfaces in the process of fretting corrosion of titanium alloy VT3-1 chromized in vacuum in pair with unprotected alloy VT3-1 and steel 40KhNMA has been studied by scanning electron microscopy, electronography, and recording the surface profile. The specific load was 200 kg/cm 2 , vibration amplitude 50 mkm and frequency 500 Hz. It has been established that pairs unprotected with coating are subjected to intensive fretting corrosion especially when they are made of titanium alloy. For the pair chromized alloy VT3-1 - unprotected alloy VT3-1 no destruction of a chromized surface is observed. Vacuum chromium coating in the pair with steel 40KhNMA reveals similar properties as in pair with a titanium alloy. The surface of a steel sample is destroyed because of fretting corrosion, though the intensity of corrosion is lower than in the case of unprotected pairs. Vacuum chromium coating is recommended for protection of titanium alloy VT3-1 from fretting corrosion in pair with steel 40KhNMA or an alloy VT3-1 especially in those cases when various organic coatings are unsuitable

  11. Durability of bends in high-temperature steam lines under the conditions of long-term operation

    Science.gov (United States)

    Katanakha, N. A.; Semenov, A. S.; Getsov, L. B.

    2015-04-01

    The article presents the results of stress-strain state computations and durability of bent and steeply curved branches of high-temperature steam lines carried out on the basis of the finite element method using the modified Soderberg formula for describing unsteady creep processes with taking the accumulation of damage into account. The computations were carried out for bends made of steel grades that are most widely used for manufacturing steam lines (12Kh1MF, 15Kh1M1F, and 10Kh9MFB) and operating at different levels of inner pressure and temperature. The solutions obtained using the developed creep model are compared with those obtained using the models widely used in practice.

  12. Certain peculiarities of structural inheritance in phase recrystallization of steel

    International Nuclear Information System (INIS)

    Mukhamedov, A.A.

    1978-01-01

    The structural inheritance in phase recrystallization of previously overheated to various temperatures industrially melted 40Kh steel and of Armco-iron has been investigated. The steels have been heated to 100O, 11O0, 1200 and 1260 deg C and cooled in the air, and in some instances, hardened (quenched) in water. The physical broadening of X-ray lines points to a nonmonotonous variation of fine structure parameters as a function of the temperature and the heating time. The inheritance effect of fine structure defects affects the steel properties obtained in a final heat treatment. The structural inheritance effect has an important bearing upon the wear resistance of steel. A purpose-oriented use of the structural inheritance effect can enhance service properties of steel parts

  13. Comparative estimation of weld-ability of medium-alloy steels

    International Nuclear Information System (INIS)

    Makarov, Eh.L.; Laz'ko, V.E.

    1977-01-01

    Weldability of various industrial steels has been investigated as affected by mutual presence of carbon and alloying elements in a wide range of concentrations. Mechanical properties and technological strength of medium alloyed steel welded joints have been compared. Technological strength parameters have been found to sharply decrease with increasing carbon content, the decrease depending on the alloying system. Resistance to hot and cold cracking is somewhat decreased by nickel and increased by molibdenum and tungsten. The best mechanical properties are displayed by steels of the Kh2GSNVM type. Industrial evidence on argon arc welding of different constructions made of steels 1.5-20 mm thick is compared to laboratory results. Accordingly, the high strength steels are divided into three groups, i.e. those manifesting good, satisfactory and poor weldability

  14. Self-ion Irradiation Damage of F/M and ODS steels

    International Nuclear Information System (INIS)

    Kang, Suk Hoon; Chun, Young-Bum; Noh, Sanghoon; Jang, Jinsung; Kim, Tae Kyu

    2014-01-01

    Oxide dispersion strengthened (ODS) ferritic steels are potential high-temperature materials that are stabilized by dispersed particles at elevated temperatures. These dispersed particles improve the tensile strength and creep rupture strength, they are expected to increase the operation temperature up to approximately 650 .deg. C and also enhance the energy efficiency of the fusion reactor. Some reports described that the nano-clusters are strongly resistant to coarsening by annealing up to 1000 .deg. C, and nanoclusters do not change after ion irradiation up to 0.7 dpa at 300 .deg. C. ODS steels will be inevitably exposed to neutron irradiation condition; the irradiation damages, creep and swelling are always great concern. The dispersed oxide particles are believed to determine the performance of the steel, even the radiation resistance. In this study, F/M and ODS model alloys of Korea Atomic Energy Research Institute (KAERI) were irradiated by Fe 3+ self-ion to emulate the neutron irradiation effect. In this study, Fe 3+ self-ion irradiation is used as means of introducing radiation damage in F/M steel and ODS steel. The ion accelerator named DuET (in Kyoto University, Japan) was used for irradiation of Fe 3+ ion by 6.4 MeV at 300 .deg. C. The maximum damage rate in F/M and ODS steels were estimated roughly 6 dpa. After radiation, point or line defects were dominantly observed in F/M steel, on the other hands, small circular cavities were typically observed in ODS steel. Nanoindentation is a useful tool to determine the irradiationinduced hardness change in the damage layer of ionirradiated iron base alloys

  15. Conversion of MX Nitrides to Modified Z-Phase in 9-12%Cr Ferritic Steels

    DEFF Research Database (Denmark)

    Cipolla, Leonardo

    for Z-phase formation was highlighted during the studies. Several 9-12%Cr commercial steels with prolonged high-temperature exposures have been investigated, too. The same mechanism of Z-phase formation observed in 12%Cr model alloys was identified in industrial 9-12%Cr steels after thousands of hours......The 9-12%Cr ferritic steels are extensively used in modern steam power plants at service temperature up to 620°C. Currently the best perform ing ferritic creep resistance steel is the ASTM Grade 92, whose high temperature strength has recently been assessed by European Creep Collaborative Committee...... in 2005 as 600°C/113MPa/10 5h. All previous attempts made in the last twenty years to develop ferritic steels for 650°C applications have failed due to the incapacity to combine the superior oxidation resistance, given by 12%Cr content, with excellent creep resistance of high-alloyed ferritic steels...

  16. Fundamental modelling of particle strengthened 9-12% Cr steels

    Energy Technology Data Exchange (ETDEWEB)

    Magnusson, Hans; Sandstroem, Rolf [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Materials Science and Engineering; Royal Inst. of Tech., Stockholm (Sweden). Brinell Centre

    2010-07-01

    Creep strength of particle strengthened 9-12% Cr steels can be predicted by fundamental modelling. The creep strength is evaluated from the state of the microstructure during creep. Particle hardening at high temperatures can be predicted by taking dislocation climb across particles into account. Work hardening is calculated from immobile dislocations in subgrain interiors and at boundaries using the composite theory. Subgrain coarsening will lower the influence of the mechanically hard boundaries. Recovery in dislocation density is predicted through static recovery by climb and dynamic recovery by locking and dipole formation. Solid solution hardening is needed in order to explain the difference in creep strength between different 9-12% Cr steels. The accumulation of large atoms such as Mo and W will slow down the dislocation climb velocity, and thereby the microstructure recovery rate. 100000h rupture strength is predicted for X20, P91, P92 steels without any use of fitting parameters. The creep strength of P91 steel with different microstructure due to Al additions. Z-phase transformation and heat affected material is presented. (orig.)

  17. Special Features of Induction Annealing of Friction Stir Welded Joints of Medium-Alloy Steels

    Science.gov (United States)

    Priymak, E. Yu.; Stepanchukova, A. V.; Bashirova, E. V.; Fot, A. P.; Firsova, N. V.

    2018-01-01

    Welded joints of medium-alloy steels XJY750 and 40KhN2MA are studied in the initial condition and after different variants of annealing. Special features of the phase transformations occurring in the welded steels are determined. Optimum modes of annealing are recommended for the studied welded joints of drill pipes, which provide a high level of mechanical properties including the case of impact loading.

  18. Creep rupture properties of oxidised 20%Cr austenitic stainless steels

    International Nuclear Information System (INIS)

    Lobb, R.C.; Ecob, R.C.

    1989-02-01

    Sheet specimens of stabilised 20%Cr/25%Ni/Nb and nitrided 20%Cr/25%Ni/Ti stainless steels, both used as fuel cladding materials in CAGRs, have been oxidised in simulated reactor gas (Co 2 /1-2%CO) for up to l.9kh at 850 0 C, including intermediate thermal cycles to room temperature. The oxidised specimens have been creep tested subsequently at 750 0 C, under conditions of constant stress. The creep rupture properties are affected differently for the two materials. For 20%Cr/25%Ni/Nb stainless steel, there was no effect of oxidation on the intrinsic microstructure, when compared with thermally aged, non-oxidised material. Any differences in creep ductility were ascribed to geometric effects in specimens of this alloy. Lower ductilities were associated with an increased incidence of pitting attack (higher oxide spallation) and it was concluded that the extent of local, rather than general, loss of section controlled the ductility. For nitrided 20%Cr/25%Ni/Ti stainless steel, the intrinsic microstructure was affected by oxidation, such that increased grain boundary precipitation of M 23 C 6 occurred. The resultant effect was for a greater tendency for intergranular failure at lower ductility than for the thermally aged material. The magnitude of this reduction could not be quantified because the specimen geometry was also changed by oxidation. In this instance, the oxidation mode that produced the most severe loss of section was grain boundary, rather than pitting, attack. This mode of attack was not linked directly to oxide fracture/spallation, but to the period of oxidation. (author)

  19. Principles of alloy design in high nitrogen 12% chromium steels

    International Nuclear Information System (INIS)

    Goecmen, A.; Ernst, P.; Holmes, P.

    1999-01-01

    12% chromium steels are hardened by a martensitic transformation and by precipitation reactions of the martensite during a subsequent tempering treatment. The original alloy design of these steels is based on the intensifying effect of C on the martensitic transformation hardening as well as on the effects of V and Mo on intensity and stability of carbide precipitation hardening reactions. Advanced alloy design of high carbon 12% chromium steels makes use of f.c.c.-MX type carbonitrides to improve grain refinement and tempering resistance, whereas alloying with about 0.05 wt.-% nitrogen already plays a decisive role. In this paper, new alloy design opportunities provided by high nitrogen are reviewed, which promise to achieve a best possible compromise between grain size limitation, particle hardening and particle stability of 12% chromium steels. The crucial effects of the solubility product of MX-type phases on grain coarsening resistance, precipitation hardening and particle stability are reviewed. The advantages of high nitrogen steels to improve these properties are rationalized to result from the lower solubility of nitrides compared with carbides. As an advantageous opportunity of the achievable higher grain coarsening resistance, the normalizing temperature in high nitrogen steels can be increased in order to increase the amount of the less soluble and thereby slow coarsening f.c.c.-nitrides. In addition, as a consequence of a higher normalizing temperature, the solubility gap of nitrides in the austenite is expanded, which in turn enables an effective precipitation hardening due to low soluble nitrides in the metastable austenite before the martensitic transformation

  20. Positron annihilation and Moessbauer studies of neutron irradiated reactor pressure vessel steels

    International Nuclear Information System (INIS)

    Brauer, G.; Matz, W.; Liszkay, L.; Molnar, B.

    1990-11-01

    Positron annihilation (lifetime, Doppler broadening) and Moessbauer studies on unirradiated, neutron irradiated and neutron irradiated plus annealed reactor pressure vessel steels (Soviet type 15Kh2NMFA) are presented. The role of microstructural properties and the formation of irradiation-induced precipitates is discussed. (orig.) [de

  1. Heat treatment effect on the properties of the EhP767 maraging steel welded joints

    International Nuclear Information System (INIS)

    Taver, E.I.; Piskarev, M.N.; Yushchenko, K.A.; Pustovit, A.I.; Anisimova, M.S.

    1977-01-01

    Heat treatment effect on properties of welded joints of maraging 03Kh13N4K13M3T (EhP767) steel with yield strength over 150 kgs/mm 2 has been investigated. It is shown, that change in impact strength of aged joints at - 196 deg C depends on the amount of residual austenite and grain size. To stabilize 20-40 % residual austenite heat treatment regimes have been developed. Recommended are quenching at 1030-1050 deg C, sub-zero treatment and aging at 520 deg C for 16 hrs

  2. Behaviour of glass and thermal protective coatings on stainless steels in the nitrogen tetroxide based coolant

    International Nuclear Information System (INIS)

    Bakalin, Yu.I.; Dobrunova, V.M.; Doroshkevich, V.N.; Nesterenko, V.B.; Trubnikov, V.P.

    1985-01-01

    The technology of application of glass and enamel protective coatings on stainless steel has been examined, their testing in the medium of nitrogen tetroxide based coolant with different content of nitric acid has been carried out, the basic characteristics of the coatings after testing have been defined. Chromium-nickel austenitic 12kh18n10t steel, widely used in the nuclear power, have been chosen as a basic object of examination. The coatings have been tested in nitrogen oxide at P=12.0 MPa, temperature 310 deg C and 0.1% HNO 3 , and also in the medium of vat residue of the rectifying tower with nitric acid content up to 25 mass %. Tests of the coatings have demonstrated their sufficiently high stability, especially of those based on enamels A-20 and BK-5. These coatings are characterised by satisfactory performance and can be used for corrosion protection of the materials used in nuclear power

  3. Structure and phase composition of titanium nitride coating on austenitic steel

    International Nuclear Information System (INIS)

    Dubovitskaya, N.V.; Kolenchenko, L.D.; Larikov, L.N.

    1989-01-01

    Structure and phase composition of titanium nitride coating deposited on 08Kh18N10T steel substrate using ''Bulat'' device are studied. Use of complex investigation methods permitted despite small coating thickness (1μm) to aquire information on hardness, porosity, to study phase composition in all coating thickness. The surface layer (∼0.1 μm) consists of ε-Ti 2 N, TiN 0.6 , TiC 0.35 , that is formed with carbon participation from oil vacuum. In more deeper layers beside ε-Ti 2 N TiC 0.14 N 0.77 is present. Effect of carbon diffusion from substrate to forming coating is stated. Gradient of element concentrations in the substrate-coating interface causes recrystallization of austenite

  4. Water vapor pressure over molten KH_2PO_4 and demonstration of water electrolysis at ∼300 °C

    International Nuclear Information System (INIS)

    Berg, R.W.; Nikiforov, A.V.; Petrushina, I.M.; Bjerrum, N.J.

    2016-01-01

    Highlights: • The vapor pressure over molten KH_2PO_4 was measured by Raman spectroscopy to be about 8 bars at ∼300 °C. • Raman spectroscopy shows that molten KH_2PO_4 under its own vapor pressure contains much dissolved water. • It is demonstrated spectroscopically that water electrolysis is possible in KH_2PO_4 electrolyte forming H_2 and O_2 at 300 °C. • Molten KH_2PO_4 is a possible electrolyte for water electrolysis. - Abstract: A new potentially high-efficiency electrolyte for water electrolysis: molten monobasic potassium phosphate, KH_2PO_4 or KDP has been investigated at temperatures ∼275–325 °C. At these temperatures, KH_2PO_4 was found to dissociate into H_2O gas in equilibrium with a melt mixture of KH_2PO_4−K_2H_2P_2O_7−KPO_3−H_2O. The water vapor pressure above the melt, when contained in a closed ampoule, was determined quantitatively vs. temperature by use of Raman spectroscopy with methane or hydrogen gas as an internal calibration standard, using newly established relative ratios of Raman scattering cross sections of water and methane or hydrogen to be 0.40 ± 0.02 or 1.2 ± 0.03. At equilibrium the vapor pressure was much lower than the vapor pressure above liquid water at the same temperature. Electrolysis was realized by passing current through closed ampoules (vacuum sealed quartz glass electrolysis cells with platinum electrodes and the electrolyte melt). The formation of mixtures of hydrogen and oxygen gases as well as the water vapor was detected by Raman spectroscopy. In this way it was demonstrated that water is present in the new electrolyte: molten KH_2PO_4 can be split by electrolysis via the reaction 2H_2O → 2H_2 + O_2 at temperatures ∼275–325 °C. At these temperatures, before the start of the electrolysis, the KH_2PO_4 melt gives off H_2O gas that pressurizes the cell according to the following dissociations: 2KH_2PO_4 ↔ K_2H_2P_2O_7 + H_2O ↔ 2KPO_3 + 2H_2O. The spectra show however that the water by

  5. Phosphorus effect on fracture properties of structural steels

    International Nuclear Information System (INIS)

    Goritskij, V.M.; Guseva, I.A.

    1985-01-01

    Phosphorus content is studied for its effect on fracture peculiarities and fracture toughness. It is supposed that the phosphorus effect on ductile fractures is associated with phosphorus segregation on the ferrite-carbide interfaces. An increase of the phosphorus content in heat-treated 10KhSND steel from 0.020 up to 0.043 wt.% results in a decrease of the pore size and asub(p) value. Close linear correlation is established between critical temperature of embrittlement T 50 and √ asub(p) or √ KC values for a number of structural steels with different phosphorus content

  6. Microstructural Evolution of AerMet100 Steel Coating on 300M Steel Fabricated by Laser Cladding Technique

    Science.gov (United States)

    Liu, Jian; Li, Jia; Cheng, Xu; Wang, Huaming

    2018-02-01

    In this paper, the process of coating AerMet100 steel on forged 300M steel with laser cladding was investigated, with a thorough analysis of the chemical composition, microstructure, and hardness of the substrate and the cladding layer as well as the transition zone. Results show that the composition and microhardness of the cladding layer are macroscopically homogenous with the uniformly distributed bainite and a small amount of retained austenite in martensite matrix. The transition zone, which spans approximately 100 μm, yields a gradual change of composition from the cladding layer to 300M steel matrix. The heat-affected zone (HAZ) can be divided into three zones: the sufficiently quenched zone (SQZ), the insufficiently quenched zone (IQZ), and the high tempered zone (HTZ). The SQZ consists of martensitic matrix and bainite, as for the IQZ and the HTZ the microstructures are martensite + tempered martensite and tempered martensite + ferrite, respectively. These complicated microstructures in the HAZ are caused by different peak heating temperatures and heterogeneous microstructures of the as-received 300M steel.

  7. Wastage-resistant characteristics of 12Cr steel tube material. Small leak sodium-water reaction test

    International Nuclear Information System (INIS)

    Shimoyama, Kazuhito

    2004-03-01

    In the water leak accident of a steam generator designed for a sodium cooled reactor in the Feasibility Study, the localization of tube failure propagation by using an advanced water leak detector will be required from the viewpoints of the safety and economical efficiency of the plant. So far, the conventional knowledge and analytical tools have been used in the investigation and evaluation of water leak phenomenon; nevertheless, there was neither test data nor the study of quantitative evaluation on the corrosion behavior, so-called wastage-resistant characteristics, of 12Cr steel tube material in sodium-water reactions. Wastage tests for the 12Cr steel tube material were conducted in small water leaks by use of the Sodium-Water Reaction Test Rig (SWAT-1R), and the data of wastage rate were obtained in the parameter of water leak rate under the constant sodium temperature and distance between leak and target tubes. The test results lead to the following conclusions: (1) The wastage-resistibility of 12Cr steel is 1.6 times greater than that of 9Cr steel and is 2.7 times greater than that of 2.25Cr-1Mo steel. (2)The wastage-resistibility of 12Cr steel increases in smaller water leaks; especially in water leak rates of 1 g/sec or less, it is more excellent than that of SUS321 stainless steel used as Monju superheater tube material. (3) Based on the correlation of wastage rate for the 9Cr steel, the correlation for the 12Cr steel has been obtained to be used for the evaluation of tube failure propagation. As the correlation of wastage rate for the 12Cr steel is based on the correlation for the 9Cr steel, it gives enough conservatism in smaller water leaks. To serve in accurately evaluating the tube failure propagation in smaller water leaks, it is necessary to obtain new correlation of wastage rate for the 12Cr steel based on the data in the wide range of water leak rates. (author)

  8. Influence of prolonged service of steam turbines on the properties of materials of rotor and vessel components

    International Nuclear Information System (INIS)

    Anfimov, V.M.; Artamonov, V.V.; Chizhik, T.A.

    1984-01-01

    The structure and mechanical properties of steam turbine elements of 25Kh1MF, 25Kh1M1FA (rotors), 15Kh1M1FL (vessel components) steels have been investigated both in initial state and after 200 000 h operation. The structure stability and phase composition of rotor steels providing conservation of heat resistance at a required level was established. Examination of vessel components showed a decrease in the yield strength by 15-20% and durability - by 10% as compared to initial ones. The conclusion on a possible prolongation of the steam turbine service life to 200 000 h is drawn. The nominal service life equals 100 000 h

  9. 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...

  10. Experimental assessment of welded joints brittle fracture on the crack arrest criterion for WWER-1000 RPV

    International Nuclear Information System (INIS)

    Blumin, A.A.; Timofeev, B.T.

    2000-01-01

    The crack arrest fracture toughness in a vessel steel used in WWER-1000 reactor, namely in steel 15Kh2NMFA and its submerged arc welded joints, produced with Sv-08KhGNMTA, Sv-12 Kh2NMFA welding wires and NF-18 M, FZ-16 A welding fluxes, is under study. Experimental studies are carried out using three heats with the chemical composition meeting the specifications. Weld specimens 100-200 mm thick are subjected to tempering according various regimes to induce the embrittlement and simulate mechanical properties (yield strength and ductile-brittle transition temperature) corresponding to those at the end of service life under neutron radiation effect. Base metal and weld properties are compared. The wide scatter is noted for experimental data on fracture toughness temperature dependences. A possibility to use the dependence of K Ia = f (T-T k ) for determining the crack arrest fracture toughness is discussed taking in account that K Ia is a stress intensity factor calculated within the frame of static fracture mechanics [ru

  11. Surface finishing and levelling of thermomechanically hardened rolled steel

    International Nuclear Information System (INIS)

    Grosval'd, V.G.; Bashchenko, A.P.; Grishkov, A.I.; Gutnik, M.V.; Kanevskij, B.L.; Nikozov, A.I.; Sedov, N.D.; Prosin, K.A.; Safonov, L.I.

    1975-01-01

    The finishing of high-strength merchant shapes from alloy steel was tried out under industrial conditions with the equipment of metallurgical plants. After thermomechanical hardening in the production line of the rolling mill, 30KhGSN2A and 40Kh1NVA steel rounds 32 and 31 mm in diameter were straightened on a two-roller straightening machine designed by the All-Union Scientific Research Institute for Metallurgical Machinery (VNII Metmash). This made possible subsequent turning and grinding of the rods. The conditions of straightening, turning and grinding have been worked so as to obtain thermomechanically strengthened and ground rolled products approximating the gauged and ground metal in shape geometry and surface finish. It is shown that the labour-consuming operation of turning can be eliminated by reducing the machining pass of the rolled product, and this lowers the labour required for the finishing operations by 75%. After grinding with 40- and 25-grain abrasive wheels, high strength rolled shapes were obtained with a diameter of 30-0.20 mm and a surface finish of class 6-5 satisfying the technical specifications. (author)

  12. The Inhibitive Effect of 2-Phenyl-3-nitroso-imidazo [1, 2-a]pyridine on the Corrosion of Steel in 0.5 M HCl Acid Solution

    Directory of Open Access Journals (Sweden)

    K. Bouhrira

    2010-01-01

    Full Text Available The effect of 2-phenyl-3-nitroso-imidazo[1,2-a]pyridine (PNIP on the corrosion inhibition of carbon-steel in 0.5 M HCl was studied by weight loss and different electrochemical techniques such as electrochemical impedance spectroscopy (EIS, potentiodynamic polarization. The obtained results showed that PNIP effectively reduces the corrosion rate of carbon steel. Inhibition efficiency (E% increases with inhibitor concentration to attain 88% at 10-3 M. Adsorption of that PNIP on the carbon steel surface in 0.5 M HCl follows the Langmuir isotherm model. E% values obtained from various methods used are in good agreement. SEM characterization of the steel surface is made.

  13. Effect of operational conditions of electroerosion machining on the surface microgeometry parameters of steels and alloys

    International Nuclear Information System (INIS)

    Foteev, N.K.

    1976-01-01

    Studies the influence of pulse duration and a series of operating conditions of a ShGI-40-440 spark-machining generator on changes in the basic surface microgeometry characteristics of components of stainless steel 1Kh18N10T, steel St 45 and hard alloy T14K8. The microgeometry characteristics of spark-machined surfaces differ significantly from the corresponding characteristics of surfaces machined by cutting and vibro-rolling

  14. Microstructural evolution in austenitic heat-resistant cast steel 35Cr25Ni12NNbRE during long-term service

    International Nuclear Information System (INIS)

    Liu Jiangwen; Jiao Dongling; Luo Chengping

    2010-01-01

    The microstructural evolution of austenitic heat-resistant cast steel 35Cr25Ni12NNbRE during aging and long-term service was investigated using optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The microstructure of the as cast steel consists of the dendritic austenite, the block-like eutectic carbide M 7 C 3 spreaded among austenitic dendrite, and a small quantity of M 23 C 6 carbide. The microstructure of the steel aged at 600 deg. C consists of eutectic carbide M 23 C 6 transformed from eutectic carbide M 7 C 3 and dendritic austenite in which fine secondary carbide particles M 23 C 6 precipitated. The precipitated carbide M 23 C 6 kept a cubic-cubic orientation relationship (OR) with austenite matrix. There existed a carbide precipitation free zone (PFZ) around the eutectic carbide. For the long-term serviced samples, the secondary carbide precipitated in the austenite strikingly increased and the PFZ disappeared. Part of the M 23 C 6 transformed into M 6 C, which always kept a twin OR, [114] M 6 C //[110] A //[110] M 23 C 6 , with the austenite and the M 23 C 6 secondary carbide. In addition, a small quantity of σ phase FeCr and ε-Cr 2 N were also identified. The effects of alloy composition and service condition on the microstructural evolution of the steel were discussed.

  15. Non-destructive automated express method for determining the inclination of chromium-nickel steels IGC

    International Nuclear Information System (INIS)

    Nazarov, A.A.; Kamenev, Yu.B.; Kuusk, L.V.; Kormin, E.G.; Vasil'ev, A.N.; Sumbaeva, T.E.

    1986-01-01

    Methods of automated control of 18-10-type steel inclination to IGC are developed and a corresponding automated testing complex (ATS) is created. 08Kh18N10T steel samples had two variants of thermal treatment: 1) 1200 deg (5 h), 600 deg (50 h); 2) 1200 deg (5 h). Methods of non-destructive automated control of 18-10-type steel inclination to IGC are developed on the basis of potentiodynamic reactivation (PR) principle. Automated testing complex is developed, which has undergone experimental running and demonstrated a high confidence of results, reliability and easy operation

  16. Nitrogen ion implantation effect on friction coefficient of tool steel

    International Nuclear Information System (INIS)

    Velichko, N.I.; Udovenko, V.F.; Markus, A.M.; Presnyakova, G.N.; Gamulya, G.D.

    1988-01-01

    Effect of nitrogen molecular ion implantation into KhVSG steel on the friction coefficient in the air and vacuum is investigated. Irradiation is carried out by the N 2 + beam with energy 120 keV and flux density 5 μ/cm 2 at room temperature in vacuum 5x10 -4 Pa. The integral dose of irradiation is 10 17 particle/cm 2 . Nitrogen ion implantation is shown to provide the formation of the modified layer changing friction properties of steel. The friction coefficient can either increase or decrease depending on implantation and test conditions. 4 refs.; 2 figs

  17. Microstructural stability of fast reactor irradiated 10 to 12% Cr ferritic-martensitic stainless steels

    International Nuclear Information System (INIS)

    Little, E.A.; Stoter, L.P.

    1982-01-01

    The strength and microstructural stability of three 10 to 12% Cr ferritic-martensitic stainless steels have been characterized following fast reactor irradiation to damage levels of 30 displacements per atom (dpa) at temperatures in the range 380 to 615 0 C. Irradiation results in either increases or decreases in room temperature hardness depending on the irradiation temperature. These strength changes can be qualitatively rationalized in terms of the combined effects of irradiation-induced interstitial dislocation loop formation and recovery of the dislocation networks comprising the initial tempered martensite structures. Precipitate evolution in the irradiated steels is associated with the nonequilibrium segregation of the elements nickel, silicon, molybdenum, chromium and phosphorus, brought about by solute-point defect interactions. The principal irradiation-induced precipitates identified are M 6 X, intermetallic chi and sigma phases and also α' (Cr-rich ferrite). The implications of the observed microstructural changes on the selection of martensitic stainless steels for fast reactor wrapper applications are briefly considered

  18. Analytical description of changes in the magnetic states of chromium-nickel steel under uniaxial elastic deformation

    Science.gov (United States)

    Gorkunov, E. S.; Yakushenko, E. I.; Zadvorkin, S. M.; Mushnikov, A. N.

    2017-12-01

    Dependences of magnetization and magnetic permeability of the 15KhN4D structural steel on the value of uniaxial stresses and magnetic field strength are obtained. A polynomial approximation fairly accurately describing the observed changes is proposed on the basis of experimental data.

  19. Impact behavior of 9-Cr and 12-Cr ferritic steels after low-temperature irradiation

    International Nuclear Information System (INIS)

    Klueh, R.L.; Vitek, J.M.; Corwin, W.R.; Alexander, D.J.

    1987-01-01

    Miniature Charpy impact specimens of 9Cr-1MoVNb and 12Cr-1MoVW steels and these steels with 1 and 2% Ni were irradiated in the High-Flux Isotope Reactor (HFIR) at 50 0 C to displacement damage levels of up to 9 dpa. Nickel was added to study the effect of transmutation helium. Irradiation caused an increase in the ductile-brittle transition temperature (DBTT). The 9Cr-1MoVNb steels, with and without nickel, showed a larger shift than the 12Cr-1MoVW steels, with and without nickel. The results indicated that helium also increased the DBTT. The same steels were previously irradiated at higher temperatures. From the present and past tests, the effect of irradiation temperature on the DBTT behavior can be evaluated. For the 9Cr-1MoVNb steel, there is a continuous decrease in the magnitude of the DBTT increase up to an irradiation temperature of about 400 0 C, after which the shift drops rapidly to zero at about 450 0 C. The DBTT of the 12Cr-1MoVW steel shows a maximum increase at an irradiation temperature of about 400 0 C and less of an increase at either higher or lower irradiation temperatures

  20. Konsep Pendidikan Akhlak dan Dakwah dalam Perspektif Dr. KH. Zakky Mubarak, MA

    Directory of Open Access Journals (Sweden)

    Muchtar Muchtar

    2017-09-01

    Full Text Available Research aims to understand role, and the concept of education and dakwah in perspective Dr. KH. Zakky Mubarak, MA. This research departs from looking at the phenomenon of human life is increasingly complex, entered the modern life and globalization present and the future, wich is characterized by technical and professional paced lives, is forecast to many people ignore the moral and religious in individual and social life. The concept of moral education in the perspective of Dr. KH. Zakky Mubarak, MA that establishes the character of the learners, provide good role models, develop the moral high level, and then apply the knowledge of good character and exemplary in real life so it can become an ingrained habit. The concept of dakwah in perspective Dr. KH. Zakky Mubarak, MA at least two steps that need to be understood by a preacher, first that of bringing the wisdom, it means explaining the wisdoms contained in worship and other Islamic activities without patronizing impression, meaning a preacher should put the words and appropriate sentence appropriate to the circumstances . The second is to mau'idlah hasanah , means giving advice that touch the heart so that the message can be embedded in the memories of audience. Dr. KH. Zakky Mubarak, MA is one of the Nahdlatul Ulama cleric who spend their time preaching, either through a lecture or through scientific papers, scientific papers written contains a lot of moral education that can be used as a reference.  Keywords: Concept of Education and Dakwah, Zakky Mubarak, Nahdlatul Ulama Abstrak Penelitian ini bertujuan untuk mengetahui peran, serta konsep pendidikan akhlak dan dakwah dalam perspektif Dr. KH. Zakky Mubarak, MA. Kesimpulan penelitian ini bahwa Konsep pendidikan akhlak dalam perspektif Dr. KH. Zakky Mubarak, MA yaitu menanamkan pemahaman tentang akhlak terhadap peserta didik, memberikan keteladanan yang baik, mengembangkan pada akhlak tingkat tinggi, dan kemudian mengaplikasikan

  1. Structure and properties of joints of two-ply steel using ''elastic'' explosives

    International Nuclear Information System (INIS)

    Gel'man, A.S.; Savel'ev, S.A.; Kulakevich, Ya.S.; Sharypov, N.A.; Drogovejko, I.Z.; Domolego, I.E.

    1980-01-01

    Some experimental data on structure and properties of compounds during cladding of sheets made of St3 with sheets of nichrome and steel 12Kh18N10T with the use of ''elastic'' explosives are presented. It is shown that the use of ''elastic'' explosives permits to decrease r parameter sufficiently, (where r - is the ratio of explosive mass to the mass of throwen phate) that reduces considerably the specific consumption explosives in comparison with the consumption conventional mixture explosives. Peculiarities of tested ''elastic'' explosives make their application perspective in two cases - at cladding of complex curved surfaces (drums, tube blanks etc.), as sell as at applications of burst chambers, where explosive mass limits dimensions of cladding blanks and details [ru

  2. High temperature strength and aging behavior of 12%Cr-15%Mn austenitic steels

    International Nuclear Information System (INIS)

    Miyahara, Kazuya; Bae, Dong-Su; Sakai, Hidenori; Hosoi, Yuzo

    1993-01-01

    High Mn-Cr austenitic steels are still considered to be an important high temperature structural material from the point of view of reduced radio-activation. The objective of the present study is to make a fundamental research of mechanical properties and microstructure of 12%Cr-15%Mn austenitic steels. Especially the effects of alloying elements of V and Ti on the mechanical properties and microstructure evolution of high Mn-Cr steels were studied. Precipitation behaviors of carbides, nitrides and σ phase are investigated and their remarkable effects on the high temperature strength are found. The addition of V was very effective for strengthening the materials with the precipitation of fine VN. Ti was also found to be beneficial for the improvement of high temperature strength properties. The results of high temperature strengths of the 12Cr-15Mn austenitic steels were compared with those of the other candidate and/or reference materials, for example, JFMS (modified 9Cr-2Mo ferritic stainless steel) and JPCAs (modified 316 austenitic stainless steels). (author)

  3. Comparison of extrapolation methods for creep rupture stresses of 12Cr and 18Cr10NiTi steels

    International Nuclear Information System (INIS)

    Ivarsson, B.

    1979-01-01

    As a part of a Soviet-Swedish research programme the creep rupture properties of two heat resisting steels namely a 12% Cr steel and an 18% Cr12% Ni titanium stabilized steel have been studied. One heat from each country of both steels were creep tested. The strength of the 12% Cr steels was similar to earlier reported strength values, the Soviet steel being some-what stronger due to a higher tungsten content. The strength of the Swedish 18/12 Ti steel agreed with earlier results, while the properties of the Soviet steel were inferior to those reported from earlier Soviet creep testings. Three extrapolation methods were compared on creep rupture data collected in both countries. Isothermal extrapolation and an algebraic method of Soviet origin gave in many cases rather similar results, while the parameter method recommended by ISO resulted in higher rupture strength values at longer times. (author)

  4. Effect of aging on the tribological and mechanical properties of a high-nitrogen stainless austenitic steel

    International Nuclear Information System (INIS)

    Korshunov, L.G.; Chernenko, N.L.; Tereshchenko, N.A.; Uvarov, A.I.

    2005-01-01

    The effect of aging, associated with predominant precipitation of vanadium nitrides (VN), on tribological and mechanical properties of austenitic steel 10Kh18AG18N5MF hardened from 1100 Deg C is studied. Metallographic, X-ray diffraction and electron microscopical methods are used to study structural transformations proceeding in the steel on aging as well as on friction loading under conditions of dry slipping friction in steel-abrasive and steel-steel pairs. It is shown that the aging at temperatures of 600-700 Deg C resulting in a considerable increase of strength properties of the steel demonstrates a relatively weak positive effect on steel resistance to abrasive and adhesive wear. It is stated that the use of aging by continuous mechanism permits attaining favourable mechanical and tribological properties in vanadium-alloying nitrogen-bearing austenitic steels [ru

  5. A KH-Domain RNA-Binding Protein Interacts with FIERY2/CTD Phosphatase-Like 1 and Splicing Factors and Is Important for Pre-mRNA Splicing in Arabidopsis

    KAUST Repository

    Chen, Tao; Cui, Peng; Chen, Hao; Ali, Shahjahan; Zhang, ShouDong; Xiong, Liming

    2013-01-01

    Eukaryotic genomes encode hundreds of RNA-binding proteins, yet the functions of most of these proteins are unknown. In a genetic study of stress signal transduction in Arabidopsis, we identified a K homology (KH)-domain RNA-binding protein, HOS5 (High Osmotic Stress Gene Expression 5), as required for stress gene regulation and stress tolerance. HOS5 was found to interact with FIERY2/RNA polymerase II (RNAP II) carboxyl terminal domain (CTD) phosphatase-like 1 (FRY2/CPL1) both in vitro and in vivo. This interaction is mediated by the first double-stranded RNA-binding domain of FRY2/CPL1 and the KH domains of HOS5. Interestingly, both HOS5 and FRY2/CPL1 also interact with two novel serine-arginine (SR)-rich splicing factors, RS40 and RS41, in nuclear speckles. Importantly, FRY2/CPL1 is required for the recruitment of HOS5. In fry2 mutants, HOS5 failed to be localized in nuclear speckles but was found mainly in the nucleoplasm. hos5 mutants were impaired in mRNA export and accumulated a significant amount of mRNA in the nuclei, particularly under salt stress conditions. Arabidopsis mutants of all these genes exhibit similar stress-sensitive phenotypes. RNA-seq analyses of these mutants detected significant intron retention in many stress-related genes under salt stress but not under normal conditions. Our study not only identified several novel regulators of pre-mRNA processing as important for plant stress response but also suggested that, in addition to RNAP II CTD that is a well-recognized platform for the recruitment of mRNA processing factors, FRY2/CPL1 may also recruit specific factors to regulate the co-transcriptional processing of certain transcripts to deal with environmental challenges. © 2013 Chen et al.

  6. A KH-Domain RNA-Binding Protein Interacts with FIERY2/CTD Phosphatase-Like 1 and Splicing Factors and Is Important for Pre-mRNA Splicing in Arabidopsis

    KAUST Repository

    Chen, Tao

    2013-10-17

    Eukaryotic genomes encode hundreds of RNA-binding proteins, yet the functions of most of these proteins are unknown. In a genetic study of stress signal transduction in Arabidopsis, we identified a K homology (KH)-domain RNA-binding protein, HOS5 (High Osmotic Stress Gene Expression 5), as required for stress gene regulation and stress tolerance. HOS5 was found to interact with FIERY2/RNA polymerase II (RNAP II) carboxyl terminal domain (CTD) phosphatase-like 1 (FRY2/CPL1) both in vitro and in vivo. This interaction is mediated by the first double-stranded RNA-binding domain of FRY2/CPL1 and the KH domains of HOS5. Interestingly, both HOS5 and FRY2/CPL1 also interact with two novel serine-arginine (SR)-rich splicing factors, RS40 and RS41, in nuclear speckles. Importantly, FRY2/CPL1 is required for the recruitment of HOS5. In fry2 mutants, HOS5 failed to be localized in nuclear speckles but was found mainly in the nucleoplasm. hos5 mutants were impaired in mRNA export and accumulated a significant amount of mRNA in the nuclei, particularly under salt stress conditions. Arabidopsis mutants of all these genes exhibit similar stress-sensitive phenotypes. RNA-seq analyses of these mutants detected significant intron retention in many stress-related genes under salt stress but not under normal conditions. Our study not only identified several novel regulators of pre-mRNA processing as important for plant stress response but also suggested that, in addition to RNAP II CTD that is a well-recognized platform for the recruitment of mRNA processing factors, FRY2/CPL1 may also recruit specific factors to regulate the co-transcriptional processing of certain transcripts to deal with environmental challenges. © 2013 Chen et al.

  7. Experimental verification of the statistical theories of scaling factor effect in fatigue fracture of steel

    International Nuclear Information System (INIS)

    Svistun, R.P.; Babej, Yu.I.; Tkachenko, N.N.

    1976-01-01

    Statistical theories of the scale effect in the fatigue failure of 40KH18N9T, 10 and 20 steels have been verified. The theories are shown to be not invariably suitable for a satisfactory exlanation of the fatigue strength of the samples with respect to their dimensions. One of the main reasons for displaying the scale effect in the process of steel fatigue is the sample self-heating, i.e. a temperature factor which in many cases overlaps a statistical one

  8. Experimental verification of the statistical theories of scaling factor effect in fatigue fracture of steel

    Energy Technology Data Exchange (ETDEWEB)

    Svistun, R P; Babei, Yu I; Tkachenko, N N [AN Ukrainskoj SSR, Lvov. Fiziko-Mekhanicheskij Inst.; L' vovskij Lesotekhnicheskij Inst. (Ukrainian SSR))

    1976-01-01

    Statistical theories of the scale effect in the fatigue failure of 40KH18N9T, 10 and 20 steels have been verified. The theories are shown to be not invariably suitable for a satisfactory exlanation of the fatigue strength of the samples with respect to their dimensions. One of the main reasons for displaying the scale effect in the process of steel fatigue is the sample self-heating, i.e. a temperature factor which in many cases overlaps a statistical one.

  9. Analysis of ductile-brittle transition shifts for standard and miniature bending specimens of irradiated steel

    International Nuclear Information System (INIS)

    Korshunov, M.E.; Korolev, Yu.N.; Krasikov, E.A.; Gabuev, N.N.; Tykhmeev, D.Yu.

    1996-01-01

    A study is made to reveal if there is a correlation between shifts in temperature curves obtained when testing thin plates and standard specimens on impact bending and fracture toughness. The tests were carried out using steel 25Kh3NM specimens irradiated by 6 x 10 19 cm -2 neutron fluence. A conclusion is made about the possibility to evaluate the degree of radiation-induced embrittlement of reactor steels on the basis of thin plate testing under quasistatic loads [ru

  10. TRANSFORMASI KURIKULUM PESANTREN: Telaah Pemikiran KH. MA. Sahal Mahfudh dan Nurcholish Madjid

    OpenAIRE

    Mukhlison Effendi; Suradi Suradi

    2016-01-01

    Abstract; Islamic boarding school is an indigenous Indonesia. Some contribution that given in the Islamization process, create a good community literacy and culture are very large. One reason, because there are Islamic boarding school curriculum transformation. Most influential enticement are KH. MA. Sahal Mahfudh and Nurcholish Madjid enticement. To knowing and determine the transformation both of those figures, the researcher take focus of study as: 1) the speculation of KH. MA. Sahal Mahfu...

  11. New method for NPP sodium coolant pipeline austenization

    International Nuclear Information System (INIS)

    Malashonok, V.A.; Rotshtejn, A.V.; Gotshalk, A.L.; Miryushchenko, E.F.

    1980-01-01

    Heat treatment technology is considered for pipelines intended for the NPP cooling systems employing sodium coolant. Various techniques are discussed which are used for protecting the pipeline internal surfaces against oxidation in the process of heat treatment. It is noted that the austenite formation of welded joints of steel 12Kh18N9 and steel Kh16N11M3 at temperatures of 1050 and 1100 deg C releases welding-induced stresses and reduces a possibility of local damages. Evacuation down to 1 mm Hg appears to be the most rational protective technique. The considered procedure of the pipeline heat treatment has been utilized for mounting the equipment of the BN-600 reactor at the Beloyarskaya NPP. The economic gain resulting from the use of the procedure, owing to decrease in argon consumption and reduction of labour input, makes up 150 000 roubles

  12. Precipitation process of Z-phase in 9-12%CR steels

    DEFF Research Database (Denmark)

    Danielsen, Hilmar Kjartansson

    2014-01-01

    Precipitation of Z-phase, Cr(V,Nb)N, is known to negatively affect creep properties of 9-12%Cr steels for power plant applications as it dissolves finely distributed MX particles, (V,Nb)N, especially in high Cr steels. As the Z-phase precipitates slowly as large particles, this causes a net drop ...... and crystallographically into Z-phase CrTaN particles. Copyright © 2014 Electric Power Research Institute, Inc. Distributed by ASM International®. All rights reserved....

  13. Enhancement of strength properties of hot rolled 10KHSND steel

    International Nuclear Information System (INIS)

    Nasibov, A.G.; Popova, L.V.; Pikulin, S.A.; Globa, N.I.

    1989-01-01

    To find out the reasons of low hot rolling yield for 10KhSND steel sheets in mechanical properties, titanium effect in the range of 0.008-0.03% concentrations is studied. It is established that the titanium content in a solid solution is conserved within 0.003-0.005%, the rest of titanium is bound to carbonitrides Ti(C, N). It is shown that alloys with 0.025-0.03% titanium content possess the increased values of ultimate and yield strength the necessary level of impact strength and good wealdability. The good steel yield, when the titanium content is sustained at the given level, increases from 40 to 85%

  14. Quality of the KhN73MBTYu alloy after electroslag remelting and vacuum arc remelting

    International Nuclear Information System (INIS)

    Shelgaeva, A.V.; Krichevets, M.I.; Shinkina, N.S.; Komissarov, A.I.

    1978-01-01

    The structure and properties of the heat-resisting KhN73MBTYu alloy are investigated after electroslag remelting (ESR) and vacuum arc (VAR) remelting in commercial furnaces. The complex investigations of the casted metal were carried out by modern methods along with the standard acceptance tests, and a number of service properties were determined. It is established that the ESR metal contains magnesium and has the reduced sulphur concentration; the alloy has more fine-grained structure at high isotropy of the properties at room and operating temperatures; higher endurance is achieved under reversal rotational bending; no laminated fractures are observed. According to the basic quality factors the ESR metal satisfies all requirements for the VAR metal. Due to exclusion of strippling of ESR electrodes and ingots the yield of steel forgings increases by 20-25% and the prime cost decreases in comparison with the industrial production of VAR metal

  15. On superplasticity of corrosion resistant ferritic-austenitic chromium-nickel steels

    Energy Technology Data Exchange (ETDEWEB)

    Surovtsev, A P; Sukhanov, V E

    1988-01-01

    The deformability of corrosion resistant chromium-nickel ferritic austenitic steel type O8Kh22N6T under tension, upsetting and torsion in the 600-1200 deg C temperature range is studied. For the deformation rate of the order of 10/sup -3/ s/sup -1/ the effect of superelasticity reveals itself at 850 deg C in the process of ferrite dynamic polymerization, in the 925-950 deg C range, at initial stages of dynamic recrystallization - the dynamic polygonization controlled by chromium carbide dissolving in steel and maximum at 1050 deg C in the process of development of austenite dynamic recrystallization with grain refinement with F/A ratio equalling 1. After upsetting in the elasticity mode at 1050 deg C the impact strength of the above steel is maximum.

  16. microstructure change in 12 % Cr steel during creep

    International Nuclear Information System (INIS)

    Winatapura, D. S.; Panjaitan, E.; Arslan, A.; Sulistioso, G.S.

    1998-01-01

    The microstructure change in steel containing of 12% Cr or DIN X20CrMoV 12 1 during creep has been studied by means of optical microscopy and Transmission Electron Microscope (TEM). The creep testing at 650 o C was conducted under constant load of 650 Mpa. The heat treatment of the specimen before creep testing was austenization, followed by tempering for 2 hours. The obtained microstructure was tempered martensitic. This microstructure consisted of the martensite laths, and distributed randomly in the matrix. During tempering, chromium carbide particles of Cr 7 C 6 less than 0,2 μmin-size were precipitated on or and in the subgrain and lath martensite grain boundary. During creep testing those particles transformed and precipitated as chrome carbide precipitates of Cr 23 C 6 . At the secondary creep stage, the void formation occurred, and then it developed into the creep cracks. At tertiary creep stage for 3554 hours, the specimen was failure. The creep cracks were informs of transgranular and intergranular modes which propagated almost perpendicular to the stress axis. From this observation, it is suggested that tempering caused the ductility of martensitic microstructure, which increased the creep resistant or Cr 12% steel

  17. Creep and long-term strength of heat-resistant steels with different structures with the account taken of the type of stress deviator

    International Nuclear Information System (INIS)

    Giginyak, F.F.; Dragunov, Yu.G.; Mozharovskaya, T.N.; Titov, V.F.

    1993-01-01

    The results of the experimental investigations into creep and long-term strength of heat-resistant steels 15Kh2MFA and 15Kh2NMFA in the initial state and after heat-treatment simulating the metal irradiation embrittlement at the end of the product service date under static loading at the complex stress state and at high temperatures are presented. The experimentally substantiated equations of state describing creep and long-term stability of materials taking into account the type of the stress state are derived. (author)

  18. Influence of crystallization conditions on formation and distribution of nonmetallic inclusions in steels

    International Nuclear Information System (INIS)

    Efimov, V.A.

    1977-01-01

    The processes were studied of the formation and the distribution of nonmetallic inclusions and the chemical inhomogeneity formation during the solidification of h steel. The variation of the character of oxides and sulfides across ingots was shown by considering st 25 and 20 Kh steels. To improve the distribution of inclusions and the stability of properties throughout the body of ingots, it is recommended to throughly deoxidize the metal, to raise the rate of solidification, to reduce the temperature gradient, to employ powder cooling agents, to use casting under a blanket of slag, to modify steel by active elements (r.e.e., Ca, Ba, Zr, B) which affect favourably the nature and the shape of the nonmetallic phase

  19. Interaction of steel, titanium and zirconium with melted chlorides containing copper and zinc

    International Nuclear Information System (INIS)

    Ozeryanaya, I.N.; Manukhina, T.I.; Shibanov, B.S.

    1976-01-01

    Cu and Zn coatings were obtained by contact displacement of their molten chlorides. Cu was deposited on Kh18N10T stainless steel, and Zn was deposited on Ti or Zr at 400-550 0 . Cu was displaced from the electrolyte by all components in the steel. A smooth coating exhibited high adhesion. According to metallography there was a transition layer of a Ni-Cr solid solution between the surface Cu layer and steel. With electronegetiol Ti and Zr, contact deposition of Zn or Cu from chloride melts was possible. The coatings were multilayer and exhibited adequate adhesion. The coating consisted of an intermetallic compound of Ti or Zr with Zn

  20. Killing Effects of an Isolated Serratia marcescens KH-001 on Diaphorina citri via Lowering the Endosymbiont Numbers

    Directory of Open Access Journals (Sweden)

    Wei Hu

    2018-05-01

    Full Text Available Huanglongbing (HLB is the most devastating citrus disease worldwide, and suppression of the Asian citrus psyllid (Diaphorina citri is regarded as an effective method to inhibit the spread of HLB. In this study, we isolated a strain named as Serratia marcescens KH-001 from D. citri nymphs suffering from disease, and evaluated its killing effect on D. citri via toxicity test and effect on microbial community in D. citri using high-throughput sequencing. Our results indicated that S. marcescens KH-001 could effectively kill 83% of D. citri nymphs, while the fermentation products of S. marcescens KH-001 only killed 40% of the D. citrinymphs. High-throughput sequencing results indicated that the S. marcescens KH-001 increased the OTU numbers from 62.5 (PBS buffer to 81.5, while significantly lowered the Shannon index compared with Escherichia coli DH5α (group E (p < 0.05. OTU analysis showed that the S. marcescens KH-001 had significantly reduced the relative abundance of endosymbionts Wolbachia, Profftella, and Carsonella in group S compared with that in other groups (p < 0.05. Therefore, the direct killing effect of the fermentation products of S. marcescens KH-001 and the indirect effect via reducing the numbers of endosymbionts (Wolbachia, Profftella, and Carsonella of D. citri endow S. marcescens KH-001 a sound killing effect on D. citri. Further work need to do before this strain is used as a sound biological control agents.

  1. Microstructural Stability and Oxidation Resistance of 9-12 Chromium Steels at Elevated Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, O.N.; Alman, D.E.; Jablonski, P.D.; Hawk, J.A.

    2006-05-01

    Various martensitic 9-12 Cr steels are utilized currently in fossil fuel powered energy plants for their good elevated temperature properties such as creep strength, steam side oxidation resistance, fire side corrosion resistance, and thermal fatigue resistance. Need for further improvements on the properties of 9-12 Cr steels for higher temperature (>600oC) use is driven by the environmental concerns (i.e., improve efficiency to reduce emissions and fossil fuel consumption). In this paper, we will discuss the results of the research done to explore new subsitutional solute solution and precipitate hardening mechanisms for improved strength of 9-12 Cr martensitic steels. Stability of the phases present in the steels will be evaluated for various temperature and time exposures. A comparison of microstructural properties of the experimental steels and commercial steels will also be presented.

    The influence of a Ce surface treatment on oxidation behavior of a commercial (P91) and several experimental steels containing 9 to 12 weight percent Cr was examined at 650ºC in flowing dry and moist air. The oxidation behavior of all the alloys without the Ce modification was significantly degraded by the presence of moisture in the air during testing. For instance the weight gain for P91 was two orders of magnitude greater in moist air than in dry air. This was accompanied by a change in oxide scale from the formation of Cr-based scales in dry air to the formation of Fe-based scales in moist air. The Ce surface treatment was very effective in improving the oxidation resistance of the experimental steels in both moist and dry air. For instance, after exposure to moist air at 650ºC for 2000 hours, an experimental alloy with the cerium surface modification had a weight gain three orders of magnitude lower than the alloy without the Ce modification and two orders of magnitude lower than P91. The Ce surface treatment suppressed the formation of Fe-based scales and

  2. TEM characterization of microstructure evolution of 12%Cr heat resistant steels

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, D.; Prat, O.; Sauthoff, G. [Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany); Garcia, J. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany); Kaysser-Pyzalla, A.R. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany); Bochum Univ. (Germany)

    2010-07-01

    A detailed characterization of the microstructure evolution of 12%Cr heat resistant steels at different creep times (100 MPa / 650 C / 8000 h) were carried out by scanning transmission electron microscopy (STEM). The results of the microstructure analysis are correlated with the mechanical properties in order to investigate the influence of different precipitates (especially M{sub 23}C{sub 6}) on the creep strength of the alloys. Precipitation of Laves phase and Z-phase was observed after several hours creep time. Very few Z-phase of the type Cr(V,Ta)N nucleating from existing (V,Ta)(C,N) was observed. Both alloys show growth and coarsening of Laves phase, meanwhile the MX carbonitrides present a very slow growth and coarsening rate. Alloys containing Laves phase, MX and M{sub 23}C{sub 6} precipitates show best creep properties. (orig.)

  3. Influence of 12% Cr martensite steel quality on power generation reliability

    International Nuclear Information System (INIS)

    Smolenska, H.; Labanowski, J.; Cwiek, J.; Glowacka, M.; Serbinski, W.

    2001-01-01

    Influence of manufacturing process and heat treatment on microstructure and mechanical properties of 12% Cr heat resistance martensitic steels has been discussed. These steels are used for elevated temperatures applications like: heat and power plants, chemical and petrochemical installations. Some cases of manufacturing mistakes of steam pipelines and turbine blades had been presented. These mistakes led to imperfect microstructure resulting in reduced lifetime and insufficient reliability of installations. (author)

  4. Microstructure and mechanical properties of two Z-phase strengthened 12%Cr martensitic steels: the effects of Cu and C

    Energy Technology Data Exchange (ETDEWEB)

    Rashidi, Masoud, E-mail: masoud.rashidi@chalmers.se [Department of Physics, Chalmers University of Technology, SE-412 96 Gothenburg (Sweden); Johansson, Lennart [Siemens Industrial Turbomachinery AB, SE-612 83 Finspong (Sweden); Andrén, Hans-Olof; Liu, Fang [Department of Physics, Chalmers University of Technology, SE-412 96 Gothenburg (Sweden)

    2017-05-10

    Z-phase strengthened 12% Cr steels are designed to combine good corrosion and creep resistance for applications in fossil fuel power plants with steam temperatures up to 650 °C. Two trial Z-phase strengthened steels were investigated, Z-steel with ultra-low C content, and ZCuC-steel with relatively high C content and Cu addition. The Z-steel has better creep strength; however, the alloy has low impact toughness due to the formation of continuous Laves-phase films at grain boundaries. Atom probe tomography, transmission electron microscopy, and scanning electron microscopy were employed to study the effects of C and Cu on the microstructure of the two steels in the as-tempered condition, and after ageing for different times. The Z-steel shows a fast transformation from TaN to Z-phase. The relatively high C content in the ZCuC-steel resulted in the formation of two categories of MX: Ta(C, N) and TaN. The phase transformation from Ta(C, N) to Z-phase is slower compared to that from TaN to Z-phase. In addition, precipitation of M{sub 23}C{sub 6} and Cu particles in the ZCuC-steel led to easier nucleation of Laves-phase, and hence a much improved toughness.

  5. Effect of Tempering Temperature on the Microstructure and Properties of Fe-2Cr-Mo-0.12C Pressure Vessel Steel

    Science.gov (United States)

    Wang, Qi-wen; Li, Chang-sheng; Peng, Huan; Chen, Jie; Zhang, Jian

    2018-03-01

    To obtain the high-temperature strength and toughness of the medium-high-temperature-pressure steel, the microstructure evolution and mechanical properties of Fe-2Cr-Mo-0.12C steel subjected to three different tempering temperatures after being normalized were investigated. The results show that the microstructure of the sample, tempered in the range 675-725 °C for 50 min, did not change dramatically, yet the martensite/austenite constituents decomposed, and the bainite lath merged together and transformed into polygonal ferrite. At the same time, the precipitate size increased with an increase in tempering temperature. With the increase in the tempering temperature from 675 to 725 °C, the impact absorbed energy of the Fe-2Cr-Mo-0.12C steel at -40 °C increased from 257 to 325 J, and the high-temperature yield strength decreased; however, the high-temperature ultimate tensile strength tempered at 700 °C was outstanding (422-571 MPa) at different tested temperatures. The variations of the properties were attributed to the decomposition of M/A constituents and the coarsening of the precipitates. Fe-2Cr-Mo-0.12C steel normalized at 930 °C and tempered at 700 °C was found to have the best combination of ductility and strength.

  6. Properties and Microstructure of Laser Welded VM12-SHC Steel Pipes Joints

    Directory of Open Access Journals (Sweden)

    Skrzypczyk A.

    2016-06-01

    Full Text Available Paper presents results of microstructure and tests of welded joints of new generation VM12-SHC martensitic steel using high power CO2 laser (LBW method with bifocal welding head. VM12-SHC is dedicated to energetic installation material, designed to replace currently used. High content of chromium and others alloying elements improve its resistance and strength characteristic. Use of VM12-SHC steel for production of the superheaters, heating chambers and walls in steam boilers resulted in various weldability researches. In article are presented results of destructive and non-destructive tests. For destructive: static bending and Vickers hardness tests, and for non-destructive: VT, RT, UT, micro and macroscopic tests were performed.

  7. Study of effect of austenite prehistory of 03Ch20N16AG6 steel on it structure and properties

    Energy Technology Data Exchange (ETDEWEB)

    Demchuk, I S; Krakhmalev, V I; Manninen, A I [Leningradskij Politekhnicheskij Inst. (USSR)

    1981-01-01

    Effect of preliminary cold working and different procedures of thermal treatment on structure and mechanical properties of stable austenite of 03Kh20N16AG6 steel is found out. It is shown that the degree of defectability of initial austenite structure predetermines the further deformation behaviour of the steel (level of strength characteristics, plasticity storage, hardening degree etc.) in the wide temperature range. Close connection of structural changes with properties should determine the choice of preliminary treatment of stable austenitic steel as applied to concrete condition of operation.

  8. Peculiar features of determination of plastic properties in bimetals

    International Nuclear Information System (INIS)

    Voronin, A.V.; Zhadan, V.T.; Osadchij, V.A.; Rumyantsev, A.V.

    1993-01-01

    Method for calculating relative elongation of sheet bimetal on the basis of data of plastic characteristics of bimetal components has been developed. Results of calculation according to suggested method differ slightly from experimental values. It was shown analytically and supported by experiments (taking St3+12Kh18N10T samples, 45+Kh12 steel as examples), that the value of bimetal area reduction coincides with the value of area reduction of less plastic component

  9. Fatigue fracture of steel after mechanical and ultrasonic strengthening

    International Nuclear Information System (INIS)

    Stotskij, I.M.

    1978-01-01

    Fatigue fracture surfaces of samples after mechanical and ultrasonic strengthening have been studied metallographically and by electron fractography. Studied was the 40Kh steel hardened from 850 deg and then tempered at 180 deg or at 550 deg C. The ultrasound power was 25 kWt, the frequency was 20 kHz, the sample rotation velocity was 39.5 m/min. Mechanical and ultrasonic treatment was found to cause structural changes (formation of a white layer) and deformation of the material under the layer. The fatigue cracks were extending beyond the white layer; their propagation involved generation and coalescence of microcracks on account of segregation of carbides. It is concluded that mechanical and ultrasonic treatment should be used for increasing the fatigue strength of low and average strength materials rather than hardened or low-tempered ones

  10. Influence of Z-phase on long-term creep stability of martensitic 9-12% Cr steels

    Energy Technology Data Exchange (ETDEWEB)

    Danielsen, Hilmar K. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Mechanical Engineering; Hald, John [DONG Energy A/S (Denmark); Vattenfall (Denmark)

    2010-07-01

    The long-term creep strength of the new generation of martensitic creep resistant 9-12%Cr steels since the well-known steel Grade 91 relies strongly on particle strengthening by fine Mn nitrides based on V and Nb. During long-term high-temperature exposures the Mn nitrides may be replaced by the thermodynamically more stable Z-phases (Cr(V,Nb)N) causing a breakdown in creep strength. Cr contents above 10.5% strongly accelerate Z-phase precipitation, which explains the lack of success for all attempts to develop martensitic creep resistant steels with high Cr content for oxidation protection. However 9%Cr steels do not seem to be affected by the Z-phase. Careful control of the Z-phase precipitation process has led to the design of experimental 12%Cr martensitic steels strengthened by fine Z-phase nitrides based on Nb or Ta. Such steels may again enable the combination of high strength and oxidation resistance in the same alloy. This opens a new pathway for further alloy development of the heat resistant martensitic steels. (orig.)

  11. Review of Z phase precipitation in 9–12 wt-%Cr steels

    DEFF Research Database (Denmark)

    Danielsen, Hilmar Kjartansson

    2016-01-01

    For high temperature applications, 9–12 wt-%Cr steels in fossil fired power plants rely upon precipitate strengthening from (V,Nb)N MX nitrides for long term creep strength. During prolonged exposure at service temperature, another nitride precipitates: Cr(V,Nb)NZ phase. The Z phases lowly replace......MX, eventually causing a breakdown in creep strength. The present paper reviews the Z phase and its behaviour in 9–12 wt-%Cr steels including thermodynamic modelling, crystal structure, nucleation process and precipitation rate as a function of chemical composition. The influence of Z phase precipitation upon...

  12. Surface deformation effects on stainless steel, Ni, Cu and Mo produced by medium energy He ions irradiation

    International Nuclear Information System (INIS)

    Constantinescu, B.; Florescu, V.; Sarbu, C.

    1993-01-01

    To investigate dose and energy dependence of surface deformation effects (blistering and flaking), different kinds of candidate CTR first wall materials as 12KH18N10T, W-4541, W-4016 and SS-304 stainless steels, Ni, Cu, Mo were irradiated at room temperature with 3.0, 4.7 and 6.8 MeV He + ions at IAP Cyclotron. The effects were investigated by means of a TEMSCAN 200 CX electron microscope and two metallographic Orthoplan Pol Leitz and Olympus microscopes. We observed two dose dependent main phenomena: blistering and flaking (craters). So, blisters occurrence on the irradiated surface is almost instantaneous when a critical dose (number of He ions accumulated in the region at the end of alpha particles range) is reached. Increasing irradiation dose, we reached flaking stage. So, isolated submicronic fissures along grain boundaries were observed on the blister skin, chronologically followed by large (5-20 μm) deep cracks of hundreds of microns in length, blisters opening and, finally, flaking appearance. (author) 8 figs., 1 tab

  13. 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)

  14. Killing Effects of an Isolated Serratia marcescens KH-001 on Diaphorina citri via Lowering the Endosymbiont Numbers.

    Science.gov (United States)

    Hu, Wei; Kuang, Fan; Lu, Zhanjun; Zhang, Ning; Chen, Tingtao

    2018-01-01

    Huanglongbing (HLB) is the most devastating citrus disease worldwide, and suppression of the Asian citrus psyllid ( Diaphorina citri ) is regarded as an effective method to inhibit the spread of HLB. In this study, we isolated a strain named as Serratia marcescens KH-001 from D. citri nymphs suffering from disease, and evaluated its killing effect on D. citri via toxicity test and effect on microbial community in D. citri using high-throughput sequencing. Our results indicated that S. marcescens KH-001 could effectively kill 83% of D. citri nymphs, while the fermentation products of S. marcescens KH-001 only killed 40% of the D. citri nymphs. High-throughput sequencing results indicated that the S. marcescens KH-001 increased the OTU numbers from 62.5 (PBS buffer) to 81.5, while significantly lowered the Shannon index compared with Escherichia coli DH5α (group E) ( p citri endow S. marcescens KH-001 a sound killing effect on D. citri . Further work need to do before this strain is used as a sound biological control agents.

  15. Acoustic emission during tensile deformation of M250 grade maraging steel

    Science.gov (United States)

    Mukhopadhyay, Chandan Kumar; Rajkumar, Kesavan Vadivelu; Chandra Rao, Bhaghi Purna; Jayakumar, Tamanna

    2012-05-01

    Acoustic emission (AE) generated during room temperature tensile deformation of varyingly heat treated (solution annealed and thermally aged) M250 grade maraging steel specimens have been studied. Deformation of microstructure corresponding to different heat treated conditions in this steel could be distinctly characterized using the AE parameters such as RMS voltage, counts and peak amplitude of AE hits (events).

  16. Cold-rolled sheets production of stainless martensite-ageing steel smelted by vacuum arc and electroslag techniques

    Energy Technology Data Exchange (ETDEWEB)

    Rivkin, A A; Grishkov, A I; Suslin, A P; Nesterenko, A A; Lola, V N [Tsentral' nyj Nauchno-Issledovatel' skij Inst. Chernoj Metallurgii, Moscow (USSR)

    1975-05-01

    In cooperation with a number of metallurgical works the production of a high strength sheet stainless maraging steel EHP678 (000KH11N10M2T) has been tested by rolling cylindrical ingots of vacuum arc smelting at the blooming (the mass of rough ingots was 5.1 to 6.0 t, that of cleaned ingots - 3.8 to 5.1 t) or rectangular ingots of electroslag smelting (13 t) at the slabbing. The recommended regimes of heating and deformation are much similar to those used for the steel-KH18N10T. The output of valid cold-rolled sheets proved to be rather low (0.24 t/t for the vacuum arc smelting and 0.30 t/t for the electroslag smelting) mainly due to the losses on cleaning and a considerable portion of wrong-size slabs. The data are presented on the steel-EHP678 properties after various heat treatments. For the production of wide cold-rolled sheets of the steel EHP678 it is recommended to use steelmaking procedure with electroslag smelting including open-hearth melting in arc furnaces, rolling of ingots at the slabbing with heating up to 1260-1280 deg C (hold-up of 4.5 to 5 hrs); electroslag smelting for rectangular section slabs, rolling of ingots of electroslag smelting at the slabbing with their heating up to 1250 deg C (hold-up of 5.5 to 6 hrs), rolling at the 1680-type mill with heating up to 1250-1260 deg C (hold-up of 4 to 4.5 hrs ensuring the rolling temperature after a rough group not below 1100 deg C), quenching of hot-rolled sheets heating up to 920-940 deg C (hold-up of 3 to 3.5 min/mm), shot peening of sheets for descaling (provided the respective equipment is available) with a subsequent short-time pickling in an acid solution and cold rolling with a summary deformation of 35 to 45 %. The steelmaking with the electroslag smelting is much more profitable as regards to the fine technology of number of the main procedures, convenient cooperation of the works and a considerably greater output of the final products out of one ton of the steel produced.

  17. A prominent figure in tatar dryhaeology. A. Kh. Khalikov’S 85th birthday anniversary

    Directory of Open Access Journals (Sweden)

    Khuzin Fayaz Sh.

    2014-06-01

    Full Text Available The article is devoted to scientific activity of Alfred Khasanovich Khalikov (May 30, 1929–July 24, 1994, an outstanding scholar, Dr. habil. (History, Professor, corresponding member of the Academy of Sciences of Tatarstan, a renowned specialist in archaeology and ancient history of the Turkic and Finno-Ugric peoples of the Volga-Ural region. A.Kh. Khalikov was a pioneer discoverer of hundreds of monuments referring to different archaeological periods, from the Paleolithic to modern times. However, the principal sphere of his scientific interests was medieval archaeology and history of the Volga region peoples. As head of major archaeological expeditions, such as the Mari, Tatar, Bilyar, “The Kazan Kremlin”, etc. ones, A.Kh. Khalikov had emerged as organizer of large-scale research in the territory of Tatarstan and other republics and regions of the Middle Volga region for 40 years,. A.Kh. Khalikov created an extensive cultural-chronological scheme of the Stone, the Chalcolithic, the Bronze and Early Iron ages in the Volga region, offered his own concept of ethnogenesis of the Finno-Ugric and Turkic peoples of the region. A.Kh. Khalikov authored over 400 articles and 20 books covering the origin and early history of the peoples of the Middle Volga and Ural regions. On his initiative, a complete list of archaeological monuments of Tatarstan in 6 volumes was created. Preservation of monuments of history and culture was an important direction of his activities. Professor A.Kh. Khalikov was engaged in fruitful teaching process at Kazan State University and created his own scientific school.

  18. The Historiography of Islamic Law: The Case of Tārīkh al-Tashrī‘ Literature

    Directory of Open Access Journals (Sweden)

    Arif Maftuhin

    2016-12-01

    Full Text Available Tārīkh al-Tashrī‘ (the history of sharia affairs is a relatively new genre of Islamic historiography and very popular among students of Islamic Law. Despite its popularity, academics of Islamic historiography seem not interested in studying it. There is hardly any academic paper seriously studied the literature. This paper is a first effort to explore the Tārīkhu’t-tashrī‘ literature through a historiographical analysis. As an initial exploration, it argues that Tārīkh al-Tashrī‘ is the latest development of Islamic historiography, developed in the 19th century, but it is a genre of the old Islamic historiography with some new elements. The new elements are influenced by both modern Western historiography and the need to re-open the supposedly closed gate of ijtihād. The paper studied books of Tārīkh al-Tashrī‘ available during the research between 2013-2015. [Tārīkh al-Tashrī‘ adalah genre yang relatif ‘baru’ dalam matarantai perkembangan historiografi Islam­. Literatur ini sangat popular dan menjadi mata kuliah wajib di fakultas-fakultas Syariah di Indonesia maupun Timur Tengah. Hanya saja, meskipun ia sangat populer sebagai mata pelajaran, Tārīkh al-Tashrī‘ belum banyak menarik minat para peneliti historiografi. Makalah in berusaha mengeksplorasi literatur Tārīkh al-Tashrī‘ dengan pendekatan historiografi. Makalah ini berpendapat bahwa Tārīkh al-Tashrī‘, meski terlihat ‘modern’ dari segi kelahirannya, tidak banyak berbeda dengan literatur historiografi klasik. Perbedaan terjadi karena adanya pengaruh historiografi Barat dalam model penulisannya dan karena kebutuhan untuk membuka kembali pintu ijtihad yang tertutup. Kajian dilakukan terhadap kitab-kitab Tārīkh al-Tashrī‘ yang dapat ditemukan selama riset antara 2013-2015 

  19. Metastable structure formation during high velocity grinding

    International Nuclear Information System (INIS)

    Samarin, A.N.; Klyuev, M.M.

    1984-01-01

    Metastable structures in surface layers of samples are; investigated during force high-velocity abrasive grinding. Samples of martensitic (40Kh13), austenitic (12Kh18N10T), ferritic (05Kh23Yu5) steels and some alloys, in particular KhN77TYuR (EhI437B), were grinded for one pass at treatment depth from 0.17 up to 2.6 mm. It is established that processes of homogenizing, recrystallization and coagulation are; developed during force high-velocity grinding along with polymorphic transformations in the zone of thermomechanical effect, that leads to changes of physical and mechanical properties of the surface

  20. Effect of laser absorption on picosecond laser ablation of Cr12MoV mold steel, 9Cr18 stainless steel and H13A cemented carbide

    Science.gov (United States)

    Wu, Baoye; Liu, Peng; Wang, Xizhao; Zhang, Fei; Deng, Leimin; Duan, Jun; Zeng, Xiaoyan

    2018-05-01

    Due to excellent properties, Cr12MoV mold steel, 9Cr18 stainless steel and H13A cemented carbide are widely used in industry. In this paper, the effect of absorption of laser light on ablation efficiency and roughness have been studied using a picosecond pulse Nd:YVO4 laser. The experimental results reveal that laser wavelength, original surface roughness and chemical composition play an important role in controlling ablation efficiency and roughness. Firstly, higher ablation efficiency with lower surface roughness is achieved on the ablation of 9Cr18 at 532, comparing with 1064 nm. Secondly, the ablation efficiency increases while the Ra of the ablated region decreases with the decrease of original surface roughness on ablation of Cr12MoV mold steel at 532 nm. Thirdly, the ablation efficiency of H13A cemented carbide is much higher than 9Cr18 stainless steel and Cr12MoV mold steel at 1064 nm. Scanning electron microscopy images reveals the formation of pores on the surface of 9Cr18 stainless steel and Cr12MoV mold steel at 532 nm while no pores are formed at 1064 nm. As to H13A cemented carbide, worm-like structure is formed at 1064 nm. The synergetic effects of the heat accumulation, plasma shielding and ablation threshold on laser ablation efficiency and machining quality were analyzed and discussed systematically in this paper.

  1. Fireside corrosion and steamside oxidation of 9-12% Cr martensitic steels exposed for long term testing

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Jensen, S. A.; Rasmussen, F.

    2009-01-01

    MoV121 and HCM12 for the 12% Cr steels. The test tubes were welded in as part of the existing final superheaters in actual plants and exposure has been conducted over a ten year period (1994-2005). Compared to the older steel types, T92 and HCM12 utilise tungsten to improve their creep strength. From......To obtain long term corrosion and steam oxidation data for the 9-12%Cr ferritic steels, test tube sections have been exposed in Amager 3 and Avedore 1 coal fired power plants in Denmark (formerly run by ENERGI E2). Thus direct comparisons can be made for T91 and T92 for the 9% Cr steels and X20Cr...... Avedore I testing, T91 and T92 can be compared for exposure times up to similar to 48 000 h exposure. From Amager 3 testing, X20, HCM12 and T92 were tested; T92 has been exposed for up to 31 000 h and X20 and HCM12 have had 84 500 h exposure. Tube sections were removed for various exposure durations...

  2. High-cycle fatigue characteristics of weldable steel for light-water reactors

    International Nuclear Information System (INIS)

    Klesnil, M.; Polak, J.; Obrtlik, K.; Troshchenko, V.T.; Mishchenko, Yu.I.; Khamaza, L.A.

    1982-01-01

    Czechoslovak and Soviet 15Kh2NMFA steel was used for running fatigue tests at temperatures of 20, 350 and 400 degC in the high-cycle range with various loading regimes. The results show that at the given temperatures in this type of steel a cyclic softening occurs. The fatigue characteristics were measured with great dispersion of results, but within this dispersion they are almost identical for various steels at the same temperature. Increased temperature results in the decrease in the amplitude of cyclic deformation stress and in the increase in the amplitude of plastic deformation. The diversity in the values of cyclic plasticity and stress response measured in the given mode may be explained by the lower level of softening and the non-homogeneous cyclic plastic deformation of material under the given constant conditions. (J.B.)

  3. Specific electrical conductivity in molten potassium dihydrogen phosphate KH2PO4 - An electrolyte for water electrolysis at ∼300°C

    DEFF Research Database (Denmark)

    Nikiforov, Aleksey Valerievich; Berg, Rolf W.; Petrushina, Irina

    2016-01-01

    The conductivity of pure molten KH2PO4 salt and four mixtures with more or less water (KH2PO4-H2O and KH2PO4-KPO3 systems, respectively) were measured at temperatures of 240-320°C and under their own water vapor pressures. Molten KH2PO4 has been proven to be a promising electrolyte for an elevated...

  4. Carbides crystalline structure of AISI M2 high-speed steel

    International Nuclear Information System (INIS)

    Serna, M.M.; Galego, E.; Rossi, J.L.

    2005-01-01

    The aim of this study was to identify the crystallographic structure of the extracted carbides of AISI M2 steel spray formed The structure determination of these carbides. The structure determination of these carbides is a very hard work. Since these structures were formed by atom migration it is not possible to reproduce them by a controlled process with a determined chemical composition. The solution of this problem is to obtain the carbide by chemical extraction from the steel. (Author)

  5. 1x2M steel performance in the BOR-60 steam generator

    International Nuclear Information System (INIS)

    Golovanov, V.N.; Shamardin, V.K.; Kondratiev, V.I.; Kryukov, F.N.; Chernobrovkin, Yu.V.; Bulanova, T.M.; Bai, V.F.

    The results from studies of 1x2M steel characteristics are presented. This steel was used as the material for the BOR-60 steam generator that had been in operation under the steam generating mode for 18,000 hs (35,000 hs in sodium). It was revealed that the pit corrosion depth on the water/steam side evaporative tube surfaces was about 0.25 μm and less and the total corrosion rate was less than 0.06 mm/y. The mechanical properties of the material were essentially similar both in the evaporator and superheater and met all the requirements imposed on. Based on the analysis of data on the decarbonizaton depth in sodium and on the corrosion damage in water and steam it was concluded that 1x2M steel can be successfully used as the steam generator material at the operating temperatures up to 470 deg. C and had sufficiently longer service-life as compared to 18,000 hs. (author)

  6. The effect of ammonium partial pressure on residual stresses in surface layer of SW7M HSS steel after vacuum nitriding 'NITROVAC'79'

    International Nuclear Information System (INIS)

    Gawronski, Z.

    1997-01-01

    The effect of the nitriding atmosphere on the residual stresses in the surface layer of the SW7M HSS steel has been investigated in the work. It has been proved that the pressure influences the distribution of those stresses to a great extent. At lower pressures (20 hPa and 40 hPa) at which only one zone is being created - the one of internal nitriding, without that of ε type nitrides on the surface - the highest residual stresses are operating on the HSS steel surface itself or eventually in the subsurface region very close to the surface. In the difference, in case of higher pressure (120 hPa and 240 hPa), the highest stresses are operating at great depth 8-12 μm from the steel surface - depending on the thickness of the ε type nitride layer created on the steel surface at those pressure. All the relevant stresses are compressive one. (author). 6 refs, 4 figs, 1 tab

  7. Microstructure and long-term creep properties of 9–12% Cr steels

    DEFF Research Database (Denmark)

    Hald, John

    2008-01-01

    Advanced microstructure characterisation and microstructure modelling has demonstrated that long-term microstructure stability in 9–12% Cr steels under technical loading conditions is equivalent to precipitate stability. Mo and W can have a positive influence on long-term creep strength of 9–12% Cr...

  8. Microstructural characterization of second phases in X10CrMoVNb9-1 and 12CrMoWCuVNb steels after long steam exposure time at 550 C

    International Nuclear Information System (INIS)

    Rodak, Kinga; Hernas, Adam; Vodarek, Vlastimil

    2015-01-01

    Microstructural changes in high alloy (9-12% Cr) creep resistant martensitic X10CrMoVNb9-1 and 12CrMoW . CuVNb steels after 100 000 h of steam exposure at 550 C have been studied using scanning transmission electron microscopy. Precipitates were identified using electron diffraction patterns and energy dispersive X-ray spectroscopy analysis. After long time exposure, a significant coarsening of M 23 C 6 carbides, and intensive precipitation of the coarse Laves phase were observed. Moreover, in the 12CrMoW . CuVNb steel, a low amount of the modified Z-phase particles was detected. The microstructures of the X10Cr . MoVNb9-1 and 12CrMoWCuVNb steels after 100 000 h of exposure differ in several aspects.

  9. Microstructural characterization of second phases in X10CrMoVNb9-1 and 12CrMoWCuVNb steels after long steam exposure time at 550 C

    Energy Technology Data Exchange (ETDEWEB)

    Rodak, Kinga; Hernas, Adam [Silesian Univ. of Technology, Inst. of Materials Science, Katowice (Poland); Vodarek, Vlastimil [VSB-Technical Univ. of Ostrava (Czech Republic)

    2015-07-15

    Microstructural changes in high alloy (9-12% Cr) creep resistant martensitic X10CrMoVNb9-1 and 12CrMoW . CuVNb steels after 100 000 h of steam exposure at 550 C have been studied using scanning transmission electron microscopy. Precipitates were identified using electron diffraction patterns and energy dispersive X-ray spectroscopy analysis. After long time exposure, a significant coarsening of M{sub 23}C{sub 6} carbides, and intensive precipitation of the coarse Laves phase were observed. Moreover, in the 12CrMoW . CuVNb steel, a low amount of the modified Z-phase particles was detected. The microstructures of the X10Cr . MoVNb9-1 and 12CrMoWCuVNb steels after 100 000 h of exposure differ in several aspects.

  10. Corrosion fatigue investigation of a high nitrogen 12% Cr-steel and of a high strength martensitic PH 13-8 Mo steel under simulated steam turbine conditions. Final report

    International Nuclear Information System (INIS)

    Schmitt-Thomas, K.G.; Schweigart, H.

    1992-01-01

    This report summarizes the results of the corrosion fatigue investigations of two martensitic stainless steels (PH 13-8 Mo, X20 CrMoV 12 1; corrosion medium: 0,01 m NaCl or 22 wt% NaCl; pH value 3 or 7). The working programm includes electrochemical and corrosion fatigue tests. Also chemical analysis, mechanical-technological and metallographical as SEM investigations were performed. (orig.)

  11. Improved the microstructures and properties of M3:2 high-speed steel by spray forming and niobium alloying

    Energy Technology Data Exchange (ETDEWEB)

    Lu, L. [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Xueyuan Road 30, Haidian District, Beijing 100083 (China); Hou, L.G., E-mail: lghou@skl.ustb.edu.cn [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Xueyuan Road 30, Haidian District, Beijing 100083 (China); Zhang, J.X.; Wang, H.B.; Cui, H.; Huang, J.F. [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Xueyuan Road 30, Haidian District, Beijing 100083 (China); Zhang, Y.A. [State Key Laboratory of Non-Ferrous Metals and Process, General Research Institute for Non-Ferrous Metals, Beijing 100088 (China); Zhang, J.S. [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Xueyuan Road 30, Haidian District, Beijing 100083 (China)

    2016-07-15

    The microstructures and properties of spray formed (SF) high-speed steels (HSSs) with or without niobium (Nb) addition were studied. Particular emphasis was placed on the effect of Nb on the solidification microstructures, decomposition of M{sub 2}C carbides, thermal stability and mechanical properties. The results show that spray forming can refine the cell size of eutectic carbides due to the rapid cooling effect during atomization. With Nb addition, further refinement of the eutectic carbides and primary austenite grains are obtained. Moreover, the Nb addition can accelerate the decomposition of M{sub 2}C carbides and increase the thermal stability of high-speed steel, and also can improve the hardness and bending strength with slightly decrease the impact toughness. The high-speed steel made by spray forming and Nb alloying can give a better tool performance compared with powder metallurgy M3:2 and commercial AISI M2 high-speed steels. - Highlights: • Spray forming can effectively refine the microstructure of M3:2 steel. • Niobium accelerates the decomposition of M{sub 2}C carbides. • Niobium increases the hardness and bending strength of spray formed M3:2 steel. • Spray-formed niobium-containing M3:2 steel has the best tool performance.

  12. Influence of Z-phase on long-term creep stability of martensitic 9-12%Cr steels

    Energy Technology Data Exchange (ETDEWEB)

    Hald, J. [DONG Energy (Denmark)]|[Vattenfall Europe AG, Berlin (Germany)]|[DTU Mechanical Engineering (Denmark); Danielsen, H.K. [DTU Mechanical Engineering (Denmark)

    2008-07-01

    The long-term creep strength of the new generation of martensitic creep resistant 9- 12% Cr steels since the well-known steel Grade 91 relies strongly on particle strengthening by fine MN nitrides based on V and Nb. During long-term hightemperature exposures the MN nitrides may be replaced by the thermodynamically more stable Z-phases (Cr(V,Nb)N) causing a breakdown in creep strength. Cr contents above 10.5% strongly accelerate Z-phase precipitation, which explains the lack of success for all attempts to develop martensitic creep resistant steels with high Cr content for oxidation protection. The Z-phase nucleation process by Cr-diffusion into pre-existing MN nitrides is rate controlling for the Z-phase transformation. More work is needed before effects of chemical composition on the nucleation process can be reliably modeled. Careful control of the Z-phase precipitation process has led to the design of experimental 12%Cr martensitic steels strengthened by Z-phase. Such steels may again enable the combination of high strength and oxidation resistance in the same alloy. This opens a new pathway for further alloy development of the heat resistant martensitic steels. (orig.)

  13. Effect of cryogenic treatment on tensile behavior of case carburized steel-815M17

    International Nuclear Information System (INIS)

    Bensely, A.; Senthilkumar, D.; Mohan Lal, D.; Nagarajan, G.; Rajadurai, A.

    2007-01-01

    The crown wheel and pinion represent the most highly stressed parts of a heavy vehicle; these are typically made of 815M17 steel. The reasons for the frequent failure of these components are due to tooth bending impact, wear and fatigue. The modern processes employed to produce these as high, durable components include cryogenic treatment as well as conventional heat treatment. It helps to convert retained austenite into martensite as well as promote carbide precipitation. This paper deals with the influence of cryogenic treatment on the tensile behavior of case carburized steel 815M17. The impetus for studying the tensile properties of gear steels is to ensure that steels used in gears have sufficient tensile strength to prevent failure when gears are subjected to tensile or fatigue loads, and to provide basic design information on the strength of 815M17 steel. A comparative study on the effects of deep cryogenic treatment (DCT), shallow cryogenic treatment (SCT) and conventional heat treatment (CHT) was made by means of tension testing. This test was conducted as per ASTM standard designation E 8M. The present results confirm that the tensile behavior is marginally reduced after cryogenic treatment (i.e. both shallow and deep cryogenic treatment) for 815M17 when compared with conventional heat treatment. Scanning electron microscopic (SEM) analysis of the fracture surface indicates the presence of dimples and flat fracture regions are more common in SCT specimens than for CHT and DCT-processed material

  14. KOMPARASI PENDIDIKAN ISLAM K.H. AHMAD DAHLAN DAN MUHAMMAD FETHULLAH GÜLEN

    Directory of Open Access Journals (Sweden)

    Mohamad Ali

    2016-05-01

    Full Text Available Islamic education is considered only oriented to the hereafter alone, teach rituals and develop a defensive posture and formisme paradigm. On the other hand, Islamic education is faced with the phenomenon of discontinuity which marked the waning value of respect for the basic values and ethics, such as honesty, discipline, tolerance. This Problem is what ignited K.H. Ahmad Dahlan (1868-1923 and Muhammad Fethullah Gülen (1838 - ... strengthening Islamic education. This study aims to understand the concepts, practices, and comparative Islamic education K.H. Ahmad Dahlan and Muhammad Fethullah Gülen. This type of research is the study of literature  with historical and philosophical approach. The results show: first, the concept of Islamic education K.H. Ahmad Dahlan stressed intregration of religious sciences and the modern sciences, tolerance, open to modernity and perfection of mind (intellect; for Fethullah Gülen education is a manifestation of Allah, which emphasizes ethics, science, and theology. Secondly, the common the sharing concept between the two are at: ideas, foundation, educational goals and teaching methods. Third, while the point of difference lies in the educational materials, dormitory educational models (boarding school and implementing a system of moving class.

  15. Protective Behavior of Poly(m-aminophenol) and Polypyrrole Coatings on Mild Steel

    Science.gov (United States)

    Yahaya, Sabrina M.; Harun, M. K.; Rosmamuhamadani, R.; Bonnia, N. N.; Ratim, S.

    2018-01-01

    Electrodeposition of polypyrrole (PPy) and poly (m-aminophenol) (PMAP) films on mild steel (MS) substrate was achieved in 0.3M oxalic acid solution and 0.3M NaOH, water:ethanol (70:30) solvent respectively using cyclic voltammetry technique. The morphology of the films constructed was determined by scanning electron microscope (SEM) while energy dispersive X-Ray analyzer (EDX) was used to establish the presence of organic PMAP and PPy film coating and its compositions. The corrosion performance of MS coated with both polymer films were investigated after 0.5 hours immersed in 0.5M NaCl aqueous solution by using polarization curves. It was found that PPy coating provides anodic protection while PMAP coating provides cathodic protection towards corrosion protection of mild steel substrate.

  16. Prospects for Martensitic 12 % Cr Steels for Advanced Steam Power Plants

    DEFF Research Database (Denmark)

    Hald, John

    2016-01-01

    and FB2 are now used in power plants up to 600–620 °C steam temperature. For higher steam temperatures up to 650 °C steels with 11–12 % Cr are needed for better resistance against steam oxidation. However, fine V and Nb based nitrides may transform to coarse Z-phase [Cr(V,Nb)N] nitrides in steels...

  17. Residual stress in a M3:2 PM high speed steel; effect of mechanical loading

    DEFF Research Database (Denmark)

    Højerslev, Christian; Odén, Magnus; Carstensen, Jesper V.

    2001-01-01

    X-ray lattice strains were investigated in an AISI M3:2 PM high-speed steel in the as heat treated condition and after exposure to alternating mechanical load. The volume changes during heat treatment were monitored with dilatometry. Hardened and tempered AISI M3:2 steel consists of tempered lath...

  18. The relation between experiments and modeling of rapidly solidified 12Cr-Mo-V stainless steel

    DEFF Research Database (Denmark)

    Pryds, Nini; Hattel, Jesper Henri

    1998-01-01

    Solidification during melt spinning of a 12Cr-Mo-V stainless steel has been experimentally studied and numerically simulated. The resulting microstructures have been related to the unknown parameter h, i.e. the heat transfer coefficient between the substrate and the melt, by fitting the heat flow...... of metastable austenite as the primary phase near the chill side of the ribbon. Upon quenching to room temperature, this austenite transformed into martensite. At a distance of about 15 mu m from the chill surface, the growth velocity of the solid/liquid interface decreased (

  19. REVIVALISME PENDIDIKAN ISLAM AWAL ABAD 20 (STUDI KRITIS PEMBARUAN PENDIDIKAN ISLAM PERSPEKTIF KH. AHMAD DAHLAN

    Directory of Open Access Journals (Sweden)

    Zetty Azizatun Ni'mah

    2016-05-01

    Full Text Available The idea of Islamic educational reform in Indonesia began in the early twentieth century. This was caused by out of concerns Muslim intellectual leaders of the secular education system which implemented the Dutch East Indies and then has a negative impact on the condition of Islamic education in Indonesia. KH. Ahmad Dahlan is pioneer figure of Islamic educational reform in Indonesia. He is of leaders respond to the condition of Islamic education in Indonesia needs to be updated in terms of objectives, materials, methods and management. This article aims to analyze thoughts KH. Ahmad Dahlan. KH. Ahmad Dahlan reform of Islamic education as well as his correlation with the current education system. This issues is examined using research methods “library research” using written materials in the form of books, magazines, journals, articles and other literatures relevant to the discussion. For data analysis the authors use the approach of history, sociology and anthropology. The results of the research that has been conducted by the author suggests that the concept of Islamic education reform in perspective KH. Ahmad: the aim of Islamic education leads to increased economic, politic, social race with modernism education, the Qur’an and Hadits are direct material examined by leaving the classic are often assessed the traditionalists, Islamic education methods abandon traditional methods, the Islamic educational institutions organized under auspices of the Muhammadiyah organization with a model of organizational leadership. Educational issues such as character building, problem solving, integration of scientific and educational innovation are concepts of education offered by KH.Ahmad Dahlan which it is an attempt to anticipate the renewal of the times and the situation in the subsequent periods.

  20. A theory of piezoelectric, elastic, and dielectric properties of the KH2PO4 family crystals under the strain u6. Phase transition and the piezoelectric effect in the KH2PO4 crystal

    International Nuclear Information System (INIS)

    Levits'kij, R.R.; Lyisnij, B.M.

    2003-01-01

    In order to study the dielectric, piezoelectric and elastic properties of ferroelectrics and antiferroelectrics of the KH 2 PO 4 family, we consider an extended proton tunneling model that takes into account the shear strain u 6 . In the four-particle cluster approximation for the short-range interactions and the mean field approximation for the long-range interaction we calculate the transverse components of the dielectric susceptibility tensor of the KH 2 PO 4 family ferroelectrics

  1. Relationship of acoustic emission to the kinetics and micromechanism of fatigue failure of high-strength steel with a martensitic structure

    International Nuclear Information System (INIS)

    Romaniv, O.N.; Kirillov, K.I.; Zima, Yu.V.; Nikiforchin, G.N.

    1987-01-01

    Techniques and results are presented for the rules of change in acoustic emission in fatigue crack propagation in hardened and low-temperature tempered 40Kh steel intended, in this study, for use as a reactor material. The results of the acoustic measurements are compared with data of quantitative aimed microfractography conducted during mechanical fracture tests

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

    International Nuclear Information System (INIS)

    Novick, V.J.; Brodrick, C.J.; Crawford, S.; Nasiatka, J.; Pierucci, K.; Reyes, V.; Sambrook, J.; Wrobel, S.; Yeary, J.

    1996-01-01

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

  3. Influence of corrosion environment composition on crack propagation in high-strength martensitic steel

    International Nuclear Information System (INIS)

    Romaniv, O.N.; Nikiforchin, G.N.; Tsirul'nik, A.T.

    1984-01-01

    The 40 Kh steel is taken as an example to investigate the dependence of electrochemical parameters in the crack tip and characteristics of corrosion static cracking resistance of martensitic steel on the composition of environment. The tests are performed in acidic and alkaline solutions prepared by adding HC or NaOH in distilled water. It is established that growth of pH value of initial solutions trom 0 to 13 brings about linear increase of a threshold stress intensity factor. It is found that acidic medium in the crack tip preserves up to pH 13 of initial medium. The possibility of corrosion crack propagation in alkaline solutions according to the mechanism of hydrogen embrittlement is proved

  4. Characterization of Aging Behavior in M250 Grade Maraging Steel Using Ultrasonic Measurements

    Science.gov (United States)

    Rajkumar, K. V.; Kumar, Anish; Jayakumar, T.; Raj, Baldev; Ray, K. K.

    2007-02-01

    Ultrasonic measurements have been carried out in M250 grade maraging steel specimens subjected to solution annealing at 1093 K for 1 hour followed by aging at 755 K for various durations in the range of 0.25 to 100 hours. The influence of aging on microstructure, room temperature hardness, and ultrasonic parameters (longitudinal and shear wave velocities and Poisson’s ratio) has been studied in order to derive correlations among these parameters in aged M250 maraging steel. Both hardness and ultrasonic velocities exhibit almost similar behaviors with aging time. They increase with the precipitation of intermetallic phases, Ni3Ti and Fe2Mo, and decrease with the reversion of martensite to austenite. Ultrasonic shear wave velocity is found to be more influenced by the precipitation of intermetallic phases, whereas longitudinal wave velocity is influenced more by the reversion of martensite to austenite. Unlike hardness and ultrasonic velocities, the Poisson’s ratio exhibits a monotonous decrease with aging time and, hence, can be used for unambiguous monitoring of the aging process in M250 maraging steel. Further, none of the parameters, i.e., hardness, ultrasonic velocity, or Poisson’s ratio, alone could identify the initiation of the reversion of austenite at early stage; however, the same could be identified from the correlation between ultrasonic velocity and Poisson’s ratio, indicating the advantage of using the multiparametric approach for comprehensive characterization of complex aging behavior in M250 grade maraging steel.

  5. Creep strength and microstructural evolution of 9-12% Cr heat resistant steels during creep exposure at 600 C and 650 C

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Martin, Francisca [Graz Univ. of Technology (Austria). Inst. for Materials Science and Welding; Panait, Clara Gabriela [MINES ParisTech, UMR CNRS, Evry (France). Centre des Materiaux; V et M France CEV, Aulnoye-Aymeries (France); Bendick, Walter [Salzgitter Mannesmann Forschung GmbH (SZMF), Duisburg (DE)] (and others)

    2010-07-01

    9-12% Cr heat resistant steels are used for applications at high temperatures and pressures in steam power plants. 12% Cr steels show higher creep strength and higher corrosion resistance compared to 9% Cr steels for short term creep exposure. However, the higher creep strength of 12 %Cr steels drops increasingly after 10,000-20,000 h of creep. This is probably due to a microstructural instability such as the precipitation of new phases (e.g. Laves phases and Z-phases), the growth of the precipitates and the recovery of the matrix. 9% Cr and 12% Cr tempered martensitic steels that have been creep tested for times up to 50,000 h at 600 C and 650 C were investigated using Transmission Electron Microscopy (TEM) on extractive replicas and thin foils together with Backscatter Scanning Electron Microscopy (BSE-SEM) to better understand the different creep behaviour of the two different steels. A significant precipitation of Laves phase and low amounts of Z-phase was observed in the 9% Cr steels after long-term creep exposure. The size distribution of Laves phases was measured by image analysis of SEM-BSE images. In the 12% Cr steel two new phases were identified, Laves phase and Z-phase after almost 30,000 h of creep test. The quantification of the different precipitated phases was studied. (orig.)

  6. [Effect of KH2PO4 on the odonto- and osteogenic differentiation potential of human stem cells from apical papillae].

    Science.gov (United States)

    Wang, Yan-ping; Wu, Jin-tao; Wang, Zi-lu; Zheng, Yang-yu; Zhang, Guang-dong; Yu, Jin-hua

    2013-01-01

    To determine the effects of KH2PO4 on the odonto- and osteogenic differentiation potential of human stem cells from apical papillae (SCAP) in vitro. SCAP were isolated and cultured respectively in alpha minimum essential medium (α-MEM) or α-MEM containing 1.8 mmol/L KH2PO4. Alkaline phosphatase (ALP) activity, alizarin red staining, real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blotting were used to examine the odonto and osteogenic potential of SCAP in the two media. SCAP cultured in α-MEM containing 1.8 mmol/L KH2PO4 exhibited a higher ALP activity [(0.370 ± 0.013) Sigma unit×min(-1)×mg(-1)] at day 3 than control group [(0.285 ± 0.008) Sigma unit×min(-1)×mg(-1)] and KH2PO4-treated SCAP formed more calcified nodules at day 5 [(0.539 ± 0.007) µg/g] and day 7 [(1.617 ± 0.042) µg/g] than those in normal medium [(0.138 ± 0.037) µg/g, P odonto- and osteogenic markers were significantly up-regulated after the stimulation of KH2PO4 at day 3 and 7 respectively, as compared with control group. 1.8 mmol/L KH2PO4 can promote the odonto and osteogenic differentiation potential of human SCAP.

  7. Comparative study of AISI M3:2 high speed steel produced through different techniques of manufacturing

    International Nuclear Information System (INIS)

    Araujo Filho, Oscar Olimpio de

    2006-01-01

    In this work AISI M3:2 high speed steels obtained through different techniques of manufacturing, submitted to the same heat treatment procedure were evaluated by measuring their mechanical properties of transverse rupture strength and hardness. Sinter 23 obtained by hot isostatic pressing (HIP), VWM3C obtained by the conventional route and a M3:2 high speed steel obtained by cold compaction of water atomized powders and vacuum sintered with and without the addition of a small quantity of carbon were evaluated after the same heat treatment procedure. The vacuum sintered M3:2 high speed steel can be an alternative to the more expensive high speed steel produced by hot isostatic pressing and with similar properties presented by the conventional one. The characterization of the vacuum sintered M3:2 high speed steel was performed by measuring the densities of the green compacts and after the sintering cycle. The sintering produced an acceptable microstructure and densities near to the theoretical. The transverse rupture strength was evaluated by means of three point bending tests and the hardness by means of Rockwell C and Vickers tests. The technique of scanning electronic microscopy (SEM) was used to evaluate the microstructure and to establish a relation with the property of transverse rupture strength. The structure was determined by means of X-ray diffraction (XRD) patterns and the retained austenite was detected to all the conditions of heat treatment. The main contribution of this work is to establish a relation between the microstructure and the mechanical property of transverse rupture strength and to evaluate the AISI M3:2 vacuum sintered high speed steel as an alternative to the similar commercial high speed steels. (author)

  8. A Study on the Fatigue-Fractured Surface of Normalized SS41 Steel and M.E.F. Dual Phase Steel by an X-ray Diffraction Technique

    International Nuclear Information System (INIS)

    Oh, Sae Wook; Park, Young Chul; Park, Soo Young; Kim, Deug Jin; Hue, Sun Chul

    1996-01-01

    This study verified the relationship between fracture mechanics parameters and X-ray parameters for normalized SS41 steel with homogeneous crystal structure and M.E.F. dual phase steel(martensite encapsulated islands of ferrite). The fatigue crack propagation test were carried out and X-ray diffraction technique was applied to fatigue fractured surface. The change in X-ray parameters(residual stress, half-value breadth) according to the depth of fatigue fractured surface were investigated. The depth of maximum plastic zone, W y , were determined on the basis of the distribution of the half-value breadth for normalized SS41 steel and that of the residual stress for M.E.F. dual phase steel. K max could be estimated by the measurement of W y

  9. Evolution of the structure and the phase composition of a bainitic structural steel during plastic deformation

    Science.gov (United States)

    Nikitina, E. N.; Glezer, A. M.; Ivanov, Yu. F.; Aksenova, K. V.; Gromov, V. E.; Kazimirov, S. A.

    2017-10-01

    The evolution of the phase composition and the imperfect substructure of the 30Kh2N2MFA bainitic structural steel subjected to compressive deformation by 36% is quantitatively analyzed. It is shown that deformation is accompanied by an increase in the scalar dislocation density, a decrease in the longitudinal fragment sizes, an increase in the number of stress concentrators, the dissolution of cementite particles, and the transformation of retained austenite.

  10. Reflection of K.H. Ahmad Dahlan’s educational ideas for school development

    Directory of Open Access Journals (Sweden)

    S. Suripto

    2017-09-01

    Full Text Available This research was aimed to reflect the form of K.H. Ahmad Dahlan’s educational ideas in schools. The kind of this research was qualitative with multi sites approach.  The research was conducted at MTs Muhammadiyah 2 and Muhammadiyah 1 Vocational School – Trenggalek.The object of this research was the form of K.H. Ahmad Dahlan’s educational ideas whereas the subject was all the school's administrators. Data were collected through deep interview, documentation and observation techniques. Data validity was tested with; credibility, transferability, and confirmability. Data analysis model was interractionally each other; data reduction, data presentation, conclusion withdrawal, and verification. The research result were; first, at MTs Muhammadiyah 2, the form of K.H. Ahmad Dahlan’s educational ideas covered: Muhammadiyah values, such as a. TBC eradication, worry attitude towards the improvement of fundamentalist religious culture in the society (LDII, b. Willingness to sacrifice attitude grown by the school founders’ core team, organizers, and administrators; c. The spirit of dakwah and dedication for the nation and the religion. Second, at Muhammadiyah 1 Vocational School, it covered a. Charity effort movement for all (rahmatan lilalamin; b. Amar maruf nahy munkar was formed in the construction of all field of life, c. Working was the spirit of movement organization. Keywords: educational ideas, school development

  11. High-Temperature Oxidation Behavior and Kinetics of Forged 12Cr-MoVW Steel

    Directory of Open Access Journals (Sweden)

    Kim Yong Hwan

    2017-06-01

    Full Text Available The oxidation kinetics of forged 12Cr-MoVW steel was investigated in an air (N2+O2 atmosphere at 873-1073 K (Δ50 K using thermogravimetric analysis. The oxidized samples were characterized using X-ray diffraction, and the surface and cross-sectional morphologies were examined using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. The forged 12Cr-MoVW steel samples exhibited parabolic behavior and a low oxidation rate compared with their as-cast counterparts. A protective oxide layer was uniformly formed at relatively low temperature (≤973 K for the forged samples, which thus exhibited better oxidation resistance than the as-cast ones. These oxides are considered solid-solution compounds such as (Fe, Cr2O3.

  12. Corrosion Fatigue Characteristics of 12Cr Alloy Steel in Na2SO4 Solution

    Science.gov (United States)

    Bae, D. H.; Cho, S. Y.

    In order to estimate reliability of 12Cr alloy steel using as the turbine blade material of the steam power plant, its corrosion fatigue characteristics in Na2SO4 solution considering its percentage and temperature that were determined from the polarization test results were investigated, and compared with the results in air. The corrosion characteristic of 12Cr alloy steel was remarkably susceptible in 12.7wt.% (IM) Na2SO4 solution, and its susceptibility increased with the solution temperature increase. The corrosion fatigue characteristics in 12.7wt.% Na2SO4 solution were similar to that of in air at 25°C. The crack growth rate was however increased with the temperature of solution increase. The reasons showing such results are due to the difference of the crack growth mechanism according to the electro-chemical activity of the corrosion factors.

  13. Specific Features of Structural-Phase State and Properties of Reactor Pressure Vessel Steel at Elevated Irradiation Temperature

    Directory of Open Access Journals (Sweden)

    E. A. Kuleshova

    2017-01-01

    Full Text Available This paper considers influence of elevated irradiation temperature on structure and properties of 15Kh2NMFAA reactor pressure vessel (RPV steel. The steel is investigated after accelerated irradiation at 300°C (operating temperature of VVER-1000-type RPV and 400°C supposed to be the operating temperature of advanced RPVs. Irradiation at 300°C leads to formation of radiation-induced precipitates and radiation defects-dislocation loops, while no carbide phase transformation is observed. Irradiation at a higher temperature (400°C neither causes formation of radiation-induced precipitates nor provides formation of dislocation loops, but it does increase the number density of the main initial hardening phase—of the carbonitrides. Increase of phosphorus concentration in grain boundaries is more pronounced for irradiation at 400°C as compared to irradiation at 300°C due to influence of thermally enhanced diffusion at a higher temperature. The structural-phase changes determine the changes of mechanical properties: at both irradiation temperatures irradiation embrittlement is mainly due to the hardening mechanism with some contribution of the nonhardening one for irradiation at 400°C. Lack of formation of radiation-induced precipitates at T = 400°C provides a small ΔTK shift (17°C. The obtained results demonstrate that the investigated 15Kh2NMFAA steel may be a promising material for advanced reactors with an elevated operating temperature.

  14. Microstructure of HFIR-irradiated 12-Cr 1 MoVW ferritic steel

    International Nuclear Information System (INIS)

    Vitek, J.M.; Klueh, R.L.

    1983-01-01

    As part of the fusion materials development program in the United States, a 12 Cr-1 MoVW ferritic steel was irradiated in the High Flux Isotope Reactor (HFIR) to a damage level of 36 dpa at 300, 400, 500, and 600 0 C. During irradiation in HFIR, a transmutation reaction of nickel results in the production of helium, to a level of 99 at. ppM in the present experiment. The microstructures were evaluated after irradiation and the results are presented. Cavities were found at all temperatures. Small cavities (3 to 9 nm) were observed after irradiation at 300, 500 and 600 0 C. At 500 and 600 0 C, the cavities were found preferentially at dislocations, lath boundaries, and prior austenite grain boundaries. After irradiation at 400 0 C, larger cavities (4 to 30 nm) were observed homogeneously distributed throughout the tempered martensite structure. The maximum swelling was 0.07% after irradiation at 400 0 C. Comparision of the results with other studies in which helium was not present at such high levels indicated helium enhances the swelling of 12 Cr-1 MoVW

  15. A luminary of tatar archaeology. To the 85th anniversary of the birth of A.Kh. Khalikov

    Directory of Open Access Journals (Sweden)

    Khuzin Fayaz Sh.

    2014-06-01

    Full Text Available The article is devoted to scientific activity of Alfred Khasanovich Khalikov (May 30, 1929–July 24, 1994, an outstanding scholar, Dr. habil. (History, Professor, corresponding member of the Academy of Sciences of Tatarstan, a renowned specialist in archaeology and ancient history of the Turkic and Finno-Ugric peoples of the Volga-Ural region. A.Kh. Khalikov was a pioneer discoverer of hundreds of monuments referring to different archaeological periods, from the Paleolithic to modern times. However, the principal sphere of his scientific interests was medieval archaeology and history of the Volga region peoples. As head of major archaeological expeditions, such as the Mari, Tatar, Bilyar, “The Kazan Kremlin”, etc. ones, A.Kh. Khalikov had emerged as organizer of large-scale research in the territory of Tatarstan and other republics and regions of the Middle Volga region for 40 years,. A.Kh. Khalikov created an extensive cultural-chronological scheme of the Stone, the Chalcolithic, the Bronze and Early Iron ages in the Volga region, offered his own concept of ethnogenesis of the Finno-Ugric and Turkic peoples of the region. A.Kh. Khalikov authored over 400 articles and 20 books covering the origin and early history of the peoples of the Middle Volga and Ural regions. On his initiative, a complete list of archaeological monuments of Tatarstan in 6 volumes was created. Preservation of monuments of history and culture was an important direction of his activities. Professor A.Kh. Khalikov was engaged in fruitful teaching process at Kazan State University and created his own scientific school.

  16. M-X Environmental Technical Report. Environmental Characteristics of Alternative Designated Deployment Areas, Steel Industry.

    Science.gov (United States)

    1980-12-22

    180,000 Utah Pl’!nouth Nucor Steel (Proposed) 350,000 I 50 175,000 ,rem Unied State Steel Corp. 2,500,000 0 0 Arizona Tempe urathion Steel Co. 180,300 75...allocated to the M-X system construction without disrupting supply to its existing customers. h. Nucor Corporation. Nucor Corporation operates three...amount of this, at least 40 percent to possibly one half, could be in the form of rebar. Nucor will have an obvious freight advantage. i. Ameron, Inc

  17. Effect of carbon content on microstructure and mechanical properties of hot-rolled low carbon 12Cr-Ni stainless steel

    International Nuclear Information System (INIS)

    Zheng, H.; Ye, X.N.; Li, J.D.; Jiang, L.Z.; Liu, Z.Y.; Wang, G.D.; Wang, B.S.

    2010-01-01

    Research highlights: → Hot-rolled ultra low carbon martensite is characterized by dislocation cells substructure. → The formation of dislocation cells is attributed to high Ms and low interstitial atoms content. → Hot-rolled ultra low carbon 12Cr-Ni stainless steel has excellent impact toughness. → Delta ferrite deteriorates the impact toughness of hot-rolled 12Cr-Ni stainless steel. - Abstract: 12Cr-Ni stainless steels containing different carbon contents from 0.004 wt.% to 0.034 wt.% were hot-rolled and air-cooled. Their corresponding microstructures were observed with optical microscope and transmission electron microscope, and the Vickers hardness, tensile and impact tests were also carried out. It was found that the martensitic morphology was significantly influenced by carbon content. The as-received ultra low carbon martensite in the steel containing 0.004 wt.% C is characterized by dislocation cells substructure. The formation of dislocation cells is attributed to high martensite finishing point (above 400 deg. C) and low interstitial atoms content. On the other hand, the martensite in the steel containing 0.034 wt.% C consists mainly of typical martensite laths because of low martensite finishing point and high interstitial atoms content which hinder dislocation motion. Furthermore, carbon content has an evident effect on the mechanical properties of 12Cr-Ni steels. The hardness and strength of the as-received steels increase with an increase in carbon content, but their elongation and impact toughness decrease with the carbon content. The steel containing 0.004 wt.% C has excellent impact toughness due to the ultra low carbon content in the martensite composed of dislocation cells.

  18. Surface modification of M50 steel by dual-ion-beam dynamic mixing

    International Nuclear Information System (INIS)

    Kuang Yuanzhu; Jan Jun; Qin Ouyang

    1994-01-01

    TaN films have many attractive characteristics, and so have been used for electronic and mechanical applications. There are many methods used for deposition of TaN films. Recently, the ion-beam dynamic mixing method has been used for thin film deposition and materials modification. In order to obtain high performance, stoichiometric composition and good adhesion we have deposited TaN films by a dual-ion-beam dynamic mixing method. This paper introduces the deposition and properties of TaN films on M50 steel by dual-ion-beam dynamic mixing. The microstructure of films was analysed by X-ray diffraction and Auger electron spectroscopy (AES). The microhardness, resistance to wear and erosion of these films were determined. The results showed that (1) the TaN films were successfully deposited on M50 steel by this method, (2) the performance, resistance to wear and erosion of M50 steel were improved by ion-beam-mixing deposition of the TaN thin films, (3) AES showed there was a mixed layer on the film interface, (4) the microhardness of the thin film depends on microstructure and thickness and (5) the microstructure and quality of the films depends on the deposition conditions, so it is important to select the proper operational parameters of ion sources. ((orig.))

  19. Hot deformation effect on the kinetics of austenite transformation under continuous cooling conditions

    International Nuclear Information System (INIS)

    Bernshtejn, M.L.; Zajmovskij, V.A.; Kisteh, N.V.; Samedov, O.V.; Faldin, S.A.

    1979-01-01

    The effect of hot deformation on the kinetics of austenite transformations in the commercial 4040Kh 40KhN, and 40KhNMA steels on continuous cooling was studied. The transformations were studied using a dilatometer of a special design which permits a specimen to be fixed quickly in holders after hot deformation. It is stated that in hot-deformed austenite the pearlite transformation proceeds at higher temperatures and in a narrower temperature range. Austenite deformation provides an opportunity to obtain a more fine ferrite-pearlite structure and ensures a uniform distribution of a structurally free ferrite in the steel bulk. The effect of hot deformation on the structure of ferrite decomposition products in the 40KhN and 40KhNMA steels is more complicated, which is connected with a substantial change in the kinetics of pearlite and intermediate transformations

  20. Effect of methanol extract of Prosopis juliflora on mild steel corrosion in 1M HCl

    OpenAIRE

    Zulfareen, Nasarullah; Kannan, Kulanthi; Venugopal, Thiruvengadam

    2016-01-01

    The Prosopis juliflora extract was investigated as a corrosion inhibitor for mild steel in 1M HCl using weight loss measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The inhibition efficiency of Prosopis juliflora increases with an increase in inhibitor concentration and temperature. Polarization studies revealed that Prosopis juliflora acts as a mixed type inhibitor for mild steel in 1M HCl. AC impedance indicates that the value of charge transfer ...

  1. Specific electrical conductivity in molten potassium dihydrogen phosphate KH2PO4 - An electrolyte for water electrolysis at ∼300°C

    DEFF Research Database (Denmark)

    Nikiforov, Aleksey Valerievich; Berg, Rolf W.; Petrushina, Irina

    2016-01-01

    The conductivity of pure molten KH2PO4 salt and four mixtures with more or less water (KH2PO4-H2O and KH2PO4-KPO3 systems, respectively) were measured at temperatures of 240-320°C and under their own water vapor pressures. Molten KH2PO4 has been proven to be a promising electrolyte for an elevated...... temperature pressurized water electrolyzer demonstrating high conductivity of ∼0.30Scm-1 at 300°C. The conductivity data are given as polynomial functions of temperature and composition. The melting point of the pure salt under its own water vapor pressure was determined to be ∼272°C....

  2. Study of strength of Dsub(y)150 gate valve case, manufactured by centrifugal casting

    International Nuclear Information System (INIS)

    Umanskaya, L.G.; Semenov, P.V.; Tinyakov, V.G.; Babkina, R.I.; Khatuntsev, Eh.V.

    1982-01-01

    A process for manufacturing centrifugal-cast gate valve body is developed. Structural strength of such items, homogeneity, ductile and strength properties over the cross section as well as the metal susceptibility to embrittlement have been investigated. Three cast gate valve bodies have been taken: one - of 20GSL steel - for hydraulic testing, and two - of 15Kh1MFL steel - for investigation into the metal properties across the valve thickness. The strength properties of the centrifugal-cast gate valve body of 15Kh1M1FL steel are stated to meet the specifications. The gate valve metal ductility (delta and PSI) is twice as high as that of a sand-cast valve. The microstructure, strength and ductility are uniform both over wall thickness and over different body cross sections

  3. AERODYNAMIC IMPROVEMENT OF KhADI 33 RACING CAR RADIATOR COMPARTMENT

    Directory of Open Access Journals (Sweden)

    A. Avershyn

    2011-01-01

    Full Text Available Aerodynamic characteristics of radiator compartment of KhADI 33 racing car on the basis of the decision of the interfaced problem of internal and external aerodynamics are numerically investigated. The rational variant of radiator compartment which is characterized by high throughput and low level of non-uniformity of speed field at the input is offered.

  4. Characterization of aging-induced microstructural changes in M250 maraging steel using magnetic parameters

    Energy Technology Data Exchange (ETDEWEB)

    Rajkumar, K.V. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Vaidyanathan, S. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Kumar, Anish [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Jayakumar, T. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India)]. E-mail: tjk@igcar.gov.in; Raj, Baldev [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Ray, K.K. [Indian Institute of Technology, Kharagpur 721302 (India)

    2007-05-15

    The best combinations of mechanical properties (yield stress and fracture toughness) of M250 maraging steel is obtained through short-term thermal aging (3-10 h) at 755 K. This is attributed to the microstructure containing precipitation of intermetallic phases in austenite-free low-carbon martensite matrix. Over-aged microstructure, containing reverted austenite degrades the mechanical properties drastically. Hence, it necessitates identification of a suitable non-destructive evaluation (NDE) technique for detecting any reverted austenite unambiguously during aging. The influence of aging on microstructure, room temperature hardness and non-destructive magnetic parameters such as coercivity (H {sub c}), saturation magnetization (M {sub s}) and magnetic Barkhausen emission (MBE) RMS peak voltage is studied in order to derive correlations between these parameters in aged M250 maraging steel. Hardness was found to increase with precipitation of intermetallics during initial aging and decrease at longer durations due to austenite reversion. Among the different magnetic parameters studied, MBE RMS peak voltage was found to be very sensitive to austenite reversion (non-magnetic phase) as they decreased drastically up on initiation of austenite reversion. Hence, this parameter can be effectively utilized to detect and quantify the reverted austenite in maraging steel specimen. The present study clearly indicates that the combination of MBE RMS peak voltage and hardness can be used for unambiguous characterization of microstructural features of technological and practical importance (3-10 h of aging duration at 755 K) in M250 grade maraging steel.

  5. Characterization of aging-induced microstructural changes in M250 maraging steel using magnetic parameters

    International Nuclear Information System (INIS)

    Rajkumar, K.V.; Vaidyanathan, S.; Kumar, Anish; Jayakumar, T.; Raj, Baldev; Ray, K.K.

    2007-01-01

    The best combinations of mechanical properties (yield stress and fracture toughness) of M250 maraging steel is obtained through short-term thermal aging (3-10 h) at 755 K. This is attributed to the microstructure containing precipitation of intermetallic phases in austenite-free low-carbon martensite matrix. Over-aged microstructure, containing reverted austenite degrades the mechanical properties drastically. Hence, it necessitates identification of a suitable non-destructive evaluation (NDE) technique for detecting any reverted austenite unambiguously during aging. The influence of aging on microstructure, room temperature hardness and non-destructive magnetic parameters such as coercivity (H c ), saturation magnetization (M s ) and magnetic Barkhausen emission (MBE) RMS peak voltage is studied in order to derive correlations between these parameters in aged M250 maraging steel. Hardness was found to increase with precipitation of intermetallics during initial aging and decrease at longer durations due to austenite reversion. Among the different magnetic parameters studied, MBE RMS peak voltage was found to be very sensitive to austenite reversion (non-magnetic phase) as they decreased drastically up on initiation of austenite reversion. Hence, this parameter can be effectively utilized to detect and quantify the reverted austenite in maraging steel specimen. The present study clearly indicates that the combination of MBE RMS peak voltage and hardness can be used for unambiguous characterization of microstructural features of technological and practical importance (3-10 h of aging duration at 755 K) in M250 grade maraging steel

  6. Fatigue-creep of martensitic steels containing 9-12% Cr: behaviour and damage

    International Nuclear Information System (INIS)

    Fournier, B.

    2007-09-01

    It is in the framework of the research programs on nuclear reactors (generation IV) that the martensitic steels containing 9-12% Cr are studied by the CEA. Most of the structures for which they are considered will be solicited in fatigue-creep at high temperature (550 C). The aim of this work is to understand and model the cyclic behaviour and the damage of these materials. The proposed modelling are based on detailed observations studies (SEM, TEM, EBSD...). The cyclic softening is attributed to the growth of the microstructure. A micro-mechanical model based on the physical parameters is proposed and leads to encouraging results. The damage results of interactions between fatigue, creep and oxidation. Two main types of damage are revealed. A model of anticipation of service time is proposed and gives very satisfying results. The possible extrapolations are discussed. (O.M.)

  7. On abnormal decomposition of supercooled austenite in carbon and alloy steels

    International Nuclear Information System (INIS)

    Parusov, V.V.; Dolzhenkov, I.I.; Podobedov, L.V.; Vakulenko, I.A.

    1980-01-01

    Residual stresses which appear as a result of thermal cycling in the temperature range of 300-700 deg C are investigated in an austenitic class steel (03Kh18N11) to ground the assumption on the effect of plastic deformation, appearing due to thermal stresses, on the mechanism of supercooled austenite decomposition. The determination of residual stresses is carried out with the help of X-ray diffraction analysis. It is established that the deformation brings about an increase in density of dislocation the interaction of which leads to the formation of a typical austenite substructure which conditions the proceeding of the eutectoid transformation according to an abnormal mechanism. It is noted, that the grain pearlite formation due to plastic and microplastic deformation of supercooled austenite induced by thermal stresses should be taken into account when developing steel heat treatment shedules [ru

  8. The design of an Fe-12Mn-O.2Ti alloy steel for low temperature use

    Science.gov (United States)

    Hwang, S. K.; Morris, J. W., Jr.

    1977-01-01

    An investigation was made to improve the low temperature mechanical properties of Fe-8 approximately 12% Mn-O 2Ti alloy steels. A two-phase(alpha + gamma) tempering in combination with cold working or hot working was identified as an effective treatment. A potential application as a Ni-free cryogenic steel was shown for this alloy. It was also shown that an Fe-8Mn steel could be grain-refined by a purely thermal treatment because of its dislocated martensitic structure and absence of epsilon phase. A significant reduction of the ductile-brittle transition temperature was obtained in this alloy. The nature and origin of brittle fracture in Fe-Mn alloys were also investigated. Two embrittling regions were found in a cooling curve of an Fe-12Mn-O 2Ti steel which was shown to be responsible for intergranular fracture. Auger electron spectroscopy identified no segregation during solution-annealing treatment. Avoiding the embrittling zones by controlled cooling led to a high cryogenic toughness in a solution-annealed condition.

  9. Inhibition of mild steel corrosion by 1,4,6-trimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile and synergistic effect of halide ion in 0.5 M H{sub 2}SO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Mourya, Punita, E-mail: mouryapunita025@gmail.com [Department of Chemistry, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005 (India); Singh, Praveen [Department of Chemistry, Banaras Hindu University, Varanasi 221005 (India); Rastogi, R.B.; Singh, M.M. [Department of Chemistry, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005 (India)

    2016-09-01

    Highlights: • TODPCN is a good corrosion inhibitor for mild steel in 0.5 M H{sub 2}SO{sub 4} solution. • Addition of iodide ion increases the inhibition efficiency of the studied nitrile derivative. • Inhibition efficiency successively increases with concentration. • XPS study has revealed the chemical composition of the protective film. - Abstract: The effect of iodide ions on inhibitive performance of 1,4,6-trimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile (TODPCN) on mild steel (MS) corrosion in 0.5 M H{sub 2}SO{sub 4} was studied using gravimetric and electrochemical measurements. TODPCN inhibits the corrosion of MS to the extent of 62.3% at its lowest concentration (0.5 mM) and its inhibition efficiency (η) further increases on increasing concentration at 298 K. The adsorption of TODPCN on MS was found to follow the Langmuir adsorption isotherm. The value of η increased on the addition of 2.0 mM KI. The value of synergism parameter being more than unity indicates that the enhanced η value in the presence of iodide ions is only due to synergism. Thus, a cooperative mechanism of inhibition exists between the iodide anion and TODPCN cations. The increase in surface coverage in the presence of KI indicates that iodide ions enhance the adsorption of TODPCN. The surface morphology of corroded/inhibited MS was studied by atomic force microscopy. X-ray photoelectron spectroscopy of inhibited MS surface was carried out to determine the composition of the adsorbed film. Some quantum chemical parameters and the Mulliken charge densities for TODPCN calculated by density functional theory provided further insight into the mechanism of inhibition.

  10. Ultrasonic Characterization of Aging Behavior in M250 Grade Maraging Steel

    Science.gov (United States)

    Yeheskel, Ori

    2009-03-01

    The increase in sound velocities during the aging of M250 maraging steel reported by Rajkumar et al. was analyzed. The present article provides a new perspective on why and to what extent the sound velocities change during aging. The main parameter that affects the elastic moduli and the sound velocities in the early and intermediate stages of aging in maraging steel is the depletion of Ni from the martensitic matrix due to Ni3Ti and Ni3Mo formation. The issue of sound velocity increase with aging time was addressed here in a few different ways to support the validity of Ni depletion.

  11. Study of the solidification of M2 high speed steel Laser Cladding coatings

    Directory of Open Access Journals (Sweden)

    Candel, J. J.

    2013-10-01

    Full Text Available High speed steel laser cladding coatings are complex because cracks appear and the hardness is lower than expected. In this paper AISI M2 tool steel coatings on medium carbon AISI 1045 steel substrate have been manufactured and after Laser Cladding (LC processing it has been applied a tempering heat treatment to reduce the amount of retained austenite and to precipitate secondary carbides. The study of metallurgical transformations by Scanning Electron Microscopy (SEM and Electron Back Scattered Diffraction (EBSD shows that the microstructure is extremely fine and complex, with eutectic transformations and MC, M2C and M6C precipitation. Therefore, after the laser coating is necessary to use post-weld heat treatments.Los recubrimientos de acero rápido por Laser Cladding (LC son complejos porque aparecen fisuras y la dureza es menor a la esperada. En este trabajo se han fabricado recubrimientos de acero AISI M2 sobre acero al carbono AISI 1045 y tras el procesado por láser, se han revenido para reducir la cantidad de austenita retenida y precipitar carburos secundarios. El estudio de las transformaciones metalúrgicas con Microscopía Electrónica de Barrido (MEB y Difracción de Electrones Retrodispersados (EBSD muestra que la microestructura es extremadamente fina y compleja, presenta transformaciones eutécticas y precipitación de carburos MC, M2C y M6C. Por tanto, tras el recubrimiento por láser es necesario recurrir a tratamientos térmicos post-soldeo.

  12. Influence of ion implanted helium on deuterium trapping in Kh18N10T stainless steel

    International Nuclear Information System (INIS)

    Tolstolutskaya, G.D.; Ruzhitskij, V.V.; Kopanets, I.E.

    2004-01-01

    The results are presented on evolution of distribution profiles and helium and deuterium thermal desorption ion implanted in steel 18Cr10NiTi. Accumulation, trapping, retention and microstructure evolution are studied; effect helium and hydrogen simultaneous implantation on these processes is also studied

  13. Structural sensitivity of cyclic crack resistance of rotor steel in gaseous hydrogen

    International Nuclear Information System (INIS)

    Romaniv, O.N.; Nikiforchin, G.N.; Kozak, L.Yu.

    1984-01-01

    Comparative evaluation of cyclic crack resistance of hardened rotor set steel 35KhN3MFA in different cstructural states during tesis in agea geseous hydrogen, in the air and in vacuum, has been mde made. It is shown, that structural sensitivity of near-threshold crack resistance of the studied rotor steel in gaseous hydrogen is to a high extent determined by the closing and morphology of fatigue crack. The decrease in crack closing (CC) observed during tests in hydrogen in low-strenght and crack branching in high-strength steels results in the fact, that in contrast to well-known notions on a higher sensitivity to hydrogen embrittlement of high-strenght alloys the negative effect of hydrogen on the near-threshold cyclic crack resistance is manifested only in steel in low-strenght state. The considered regularities in crack growth in low-alloyed steel under the effect of gaseous hydrogen are just only for high-frequency loading. In all probability in the case of fatigue crack growth (GCG) at low frequencies of loading not only the medium activity, but also the role o, closing and crack geometty in the kinetics of fatigue fracture, the clarifying of which requires further studieds, will change

  14. Development and use of data base on mechanical properties of materials in power engineering

    International Nuclear Information System (INIS)

    Popov, A.A.; Shchukina, E.G.; Karaev, A.B.

    1987-01-01

    The structure of a data base on the properties of materials used in reactor engineering is considered. The data base presents a factographic automated data retrieval system, containing test results on the 15Kh2NMFA, 15Kh2NMFA-A, 15Kh2MFA, 10GN2MFA, 22K reactor vessel steels and also the data on the A533, A508 and A304 steels taken from literature. The system is realized using the VAN6 minicomputer and operates in a dialogue mode. Software of the system is arranged by module scheme and realized using the BASIC language. Results of tensile, impact, hardness, fatigue, brittle hardness, radiation resistance, high-temperature strength and heat-resistance tests and data on the thermal properties of the alloys are introduced into the system. Prior to the input in the system the information is subjected to additional expert analysis for completeness and authenticity. The main function of the data base considered consists in the systematization of a large volume of experimental data, which envisages arbitrary retrieval and subsequent analysis using statistical methods. The system contains approximately 15 thousand records on magnetic discs. The total volume of the store is 20 M byte. The system capabilities are demonstrated when analyzing the effects of aalloying additions on mechanical properties of the 15Kh2NMFA steel

  15. Numerical and experimental study of creep of grade 91 steel at high temperature

    International Nuclear Information System (INIS)

    Lim, R.

    2011-01-01

    Grade 91 steel is a suitable candidate for structural components of the secondary and the vapour of the generation IV nuclear reactors. Their in-service lifetime will be extended to 60 years. It is necessary to consider the mechanisms involved-term during long creep to propose more reliable predictions of creep lifetimes. Necking is the main failure mechanism for creep lifetimes up to 160 kh at 500 C and 94 kh at 600 C. Necking modelling including the material creep softening leads to two bound laws including experimental lifetimes of a large number of tempered martensitic steels loaded up to 200 kh at temperature 500-700 C. The observed creep intergranular cavities are shown to affect very weekly creep strain rate. The prediction of the cavity evolution will allow estimating creep lifetimes out of experimental data domain. Their nucleation and growth, supposed to be associated to vacancy diffusion, are modelled using two classical models. The first one considers instantaneous nucleation (Raj and Ashby) and the second one continuous nucleation obeying the Dyson law (Riedel). The second one leads to two bound laws, more stable with respect to the parameter values. It allows predicting final sizes of cavities in reasonable agreement with the measured ones. Nevertheless, nucleation rate should be estimated from measured cavity densities. Nucleation of cavities by diffusion is simulated using the Raj model. This model does not allow predicted final cavity densities in agreement with the measured ones, even by considering cavity nucleation at precipitates/Laves interfaces experimentally observed and the maximum local stress concentration of a factor 2 computed using finite element calculation in a 2D plane strain hypothesis based on either simulated or real microstructures containing triple points or precipitates/Laves phases. The use of the Dyson law allows us to propose predictions of long-term creep lifetimes. Lifetime predicted using the diffusion-induced growth

  16. Metallurgic study of the steel Z8CDWV12

    Energy Technology Data Exchange (ETDEWEB)

    Loier, C.; Ottmann, M.C.; Risacher, R.; Leymonie, C.

    1984-01-01

    Steel Z8CDWV12 has a duplex structure showing ferrite and carbide-rich areas. It is used by Alsthom-Atlantique for making steam turbine nozzles. CCT diagram was plotted and enabled carbide-rich areas transformations to be understood. It was demonstrated that treatments commonly called temperings were in fact intercritical treatments. The variation of tensile and impact properties was determined as a function of the initial quenching rate and of intercritical treatment temperature. Results enable convenient heat treatments to be determined as a function of plate thickness.

  17. Analysis of nature of brazed joints fracture under operating conditions

    International Nuclear Information System (INIS)

    Orlov, A.V.; Gura, P.M.

    1985-01-01

    Technique establishing causes leading to brazed joint fracture in pressure boundary components, operating under heavy conditions of high temperature and corrosive medium is described. Some cases of tube brazed joint fractures in a superheater of 12Kh1MF and 08Kh18N10T steels are considered. The attention is paid on using metallography for determination of mechanical or corrosion fracture properties. The diagram is developed permitting to take into account the interrelation between the fracture area in the given zone and its strength

  18. 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)

  19. Studies on the effect of a newly synthesized Schiff base compound from phenazone and vanillin on the corrosion of steel in 2M HCl

    International Nuclear Information System (INIS)

    Emreguel, Kaan C.; Hayvali, Mustafa

    2006-01-01

    The inhibiting action of a Schiff base 4-[(4-hydroxy-3-hydroxymethyl-benzylidene)-amino]-1,5-dimethyl-2-phenyl-1,2 -dihydro-pyrazol-3-one (phv), derived from 4-amino-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (phz) and 4-hydroxy-3-methoxy-benzaldehyde (vn), towards the corrosion behavior of steel in 2M HCl solution has been studied using weight loss, polarization and electrochemical impedance spectroscopy (EIS) techniques. Although vn and phz were found to retard the corrosion rate of steel, the compound synthesized from vn and phz was seen to retard the corrosion rate even more. At constant temperature, the corrosion rate decreases with increasing inhibitor concentration. However, at any inhibitor concentration the increase in temperature leads to an increase in the corrosion rate of steel. The activations energies, ΔE a , as well as other thermodynamic parameters (ΔG ads 0 , ΔH ads 0 ) for the inhibitor process were calculated. The inhibitor efficiencies calculated from all the applied methods were in agreement and were found to be in the order: phv>phz>vn

  20. Thermodynamics of complex structures formed between single-stranded DNA oligomers and the KH domains of the far upstream element binding protein

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Kaushik; Sinha, Sudipta Kumar; Bandyopadhyay, Sanjoy, E-mail: sanjoy@chem.iitkgp.ernet.in [Molecular Modeling Laboratory, Department of Chemistry, Indian Institute of Technology, Kharagpur 721302 (India)

    2016-05-28

    The noncovalent interaction between protein and DNA is responsible for regulating the genetic activities in living organisms. The most critical issue in this problem is to understand the underlying driving force for the formation and stability of the complex. To address this issue, we have performed atomistic molecular dynamics simulations of two DNA binding K homology (KH) domains (KH3 and KH4) of the far upstream element binding protein (FBP) complexed with two single-stranded DNA (ss-DNA) oligomers in aqueous media. Attempts have been made to calculate the individual components of the net entropy change for the complexation process by adopting suitable statistical mechanical approaches. Our calculations reveal that translational, rotational, and configurational entropy changes of the protein and the DNA components have unfavourable contributions for this protein-DNA association process and such entropy lost is compensated by the entropy gained due to the release of hydration layer water molecules. The free energy change corresponding to the association process has also been calculated using the Free Energy Perturbation (FEP) method. The free energy gain associated with the KH4–DNA complex formation has been found to be noticeably higher than that involving the formation of the KH3–DNA complex.

  1. Synthesis and characterization of a novel organic corrosion inhibitor for mild steel in 1 M hydrochloric acid

    Science.gov (United States)

    Ahmed, Mohammed H. Othman; Al-Amiery, Ahmed A.; Al-Majedy, Yasmin K.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Gaaz, Tayser Sumer

    2018-03-01

    The synthesis and characterization of a novel organic corrosion inhibitor (4-(3-mercapto-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazin-6-yl)phenol), for mild steel in 1 M hydrochloric acid (HCl) has been successfully reported for the first time. The inhibitor evaluated as corrosion inhibitor for mild steel in 1 M of Hydrochloric acid solution using electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation (EFM) measurement techniques. Changes in the impedance parameters suggested an adsorption of the inhibitor onto the mild steel surface, leading to the formation of protective films. The results show that the inhibition efficiencies increased with increasing the concentrations of the inhibitors and decreased with increasing temperature. The maximum inhibition efficiency up to 67% at the maximum concentration 0.5 mM. This shows that those inhibitors are effective in helping to reduce and slowing down the corrosion process that occurs to mild steel with a hydrochloric acid solution by providing an organic inhibitor for the mild steel that can be weakened by increasing the temperature. The adsorption process of the synthesized organic inhibitor depends on its electronic characteristics in addition to steric effects and the nature of metal surface, temperature degree and the varying degrees of surface-site activity. The synthesized inhibitor molecules were absorbed by metal surface and follow Langmuir isotherms.

  2. Changing in Fatigue Life of 300 M Bainitic Steel After Laser Carburizing and Plasma Nitriding

    Directory of Open Access Journals (Sweden)

    Abdalla Antonio J.

    2018-01-01

    Full Text Available In this work 300M steel samples is used. This high-strength steel is used in aeronautic and aerospace industry and other structural applications. Initially the 300 M steel sample was submitted to a heat treatment to obtain a bainític structure. It was heated at 850 °C for 30 minutes and after that, cooled at 300 °C for 60 minutes. Afterwards two types of surface treatments have been employed: (a using low-power laser CO2 (125 W for introducing carbon into the surface and (b plasma nitriding at a temperature of 500° C for 3 hours. After surface treatment, the metallographic preparation was carried out and the observations with optical and electronic microscopy have been made. The analysis of the coating showed an increase in the hardness of layer formed on the surface, mainly, among the nitriding layers. The mechanical properties were analyzed using tensile and fatigue tests. The results showed that the mechanical properties in tensile tests were strongly affected by the bainitic microstructure. The steel that received the nitriding surface by plasma treatment showed better fatigue behavior. The results are very promising because the layer formed on steel surface, in addition to improving the fatigue life, still improves protection against corrosion and wear.

  3. INFLUENCE OF HEAT TREATMENT ON THE MICROSTRUCTURE AND TOUGHNESS OF BÖHLER M333 ISOPLAST STEEL

    OpenAIRE

    Perko, J.; Redl, C.; Leitner, H.

    2009-01-01

    In this work the through hardenability and the influence of the heat treatment parameters (austenitizingtemperature, cooling parameter ? and tempering temperature) on the microstructure and the achievabletoughness level of Böhler M333 ISOPLAST are investigated. The results are compared to the standardizedtool steel grade DIN 1.2083. The investigations showed that the cooling parameter ? has a strong influenceon the impact toughness of M333 ISOPLAST plastic mould steel. The toughness is reduce...

  4. Account of low temperature hardening in calculation of permissible stresses

    International Nuclear Information System (INIS)

    Novikov, N.V.; Ul'yanenko, A.P.; Gorodyskij, N.I.

    1980-01-01

    Suggested is a calculation scheme of permissible stresses with the account of temperature hardening for steels and alloys, the dependences of strength, plasticity and rupture work of which on cooling temperature do not have threshold changes in a wide range of low temperatures (from 300 to 4.2 K). Application of the suggested scheme is considered on the example of 12Kh18N10T austenitic chromium-nickel steel

  5. Characterization of aging-induced microstructural changes in M250 maraging steel using magnetic parameters

    Science.gov (United States)

    Rajkumar, K. V.; Vaidyanathan, S.; Kumar, Anish; Jayakumar, T.; Raj, Baldev; Ray, K. K.

    2007-05-01

    The best combinations of mechanical properties (yield stress and fracture toughness) of M250 maraging steel is obtained through short-term thermal aging (3-10 h) at 755 K. This is attributed to the microstructure containing precipitation of intermetallic phases in austenite-free low-carbon martensite matrix. Over-aged microstructure, containing reverted austenite degrades the mechanical properties drastically. Hence, it necessitates identification of a suitable non-destructive evaluation (NDE) technique for detecting any reverted austenite unambiguously during aging. The influence of aging on microstructure, room temperature hardness and non-destructive magnetic parameters such as coercivity ( Hc), saturation magnetization ( Ms) and magnetic Barkhausen emission (MBE) RMS peak voltage is studied in order to derive correlations between these parameters in aged M250 maraging steel. Hardness was found to increase with precipitation of intermetallics during initial aging and decrease at longer durations due to austenite reversion. Among the different magnetic parameters studied, MBE RMS peak voltage was found to be very sensitive to austenite reversion (non-magnetic phase) as they decreased drastically up on initiation of austenite reversion. Hence, this parameter can be effectively utilized to detect and quantify the reverted austenite in maraging steel specimen. The present study clearly indicates that the combination of MBE RMS peak voltage and hardness can be used for unambiguous characterization of microstructural features of technological and practical importance (3-10 h of aging duration at 755 K) in M250 grade maraging steel.

  6. Lattice defect inheritance during γ-α-γ transformation in steel having no ''reverse'' (martensite) transition during austenization

    International Nuclear Information System (INIS)

    Bernshtejn, M.L.; Zajmovskij, V.A.; Kozlova, A.G.; Kolupaeva, T.L.

    1979-01-01

    An investigation was carried out, using an electron microscope technique, of the substructure of austenite in the 120Kh3G steel. It was shown that the austenite substructure, resulting from high-temperature mechanical working, is inherited on deep cooling by the low-temperature phase (martensite), and in subsequent heating is again inherited by austenite. If the disintegration of the hot-deformed austenite takes place in the pearlite phase, reheating gives rise to an austenite free from the substructure

  7. Synthesis and characterization of a novel organic corrosion inhibitor for mild steel in 1 M hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Mohammed H. Othman Ahmed

    2018-03-01

    Full Text Available The synthesis and characterization of a novel organic corrosion inhibitor (4-(3-mercapto-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazin-6-ylphenol, for mild steel in 1 M hydrochloric acid (HCl has been successfully reported for the first time. The inhibitor evaluated as corrosion inhibitor for mild steel in 1 M of Hydrochloric acid solution using electrochemical impedance spectroscopy (EIS, and electrochemical frequency modulation (EFM measurement techniques. Changes in the impedance parameters suggested an adsorption of the inhibitor onto the mild steel surface, leading to the formation of protective films. The results show that the inhibition efficiencies increased with increasing the concentrations of the inhibitors and decreased with increasing temperature. The maximum inhibition efficiency up to 67% at the maximum concentration 0.5 mM. This shows that those inhibitors are effective in helping to reduce and slowing down the corrosion process that occurs to mild steel with a hydrochloric acid solution by providing an organic inhibitor for the mild steel that can be weakened by increasing the temperature. The adsorption process of the synthesized organic inhibitor depends on its electronic characteristics in addition to steric effects and the nature of metal surface, temperature degree and the varying degrees of surface-site activity. The synthesized inhibitor molecules were absorbed by metal surface and follow Langmuir isotherms. Keywords: Corrosion, Inhibitor, Mild steel, EIS spectroscopy

  8. Effect of hydroxyl group position at imine structure on corrosion inhibition of mild steel in 0.5 m NaCl

    Science.gov (United States)

    Mohd, Yusairie; Dzolin, Syaidah Athirah; Bahron, Hadariah; Halim, Nurul Huda Abdul

    2017-12-01

    Corrosion is inherent for mild steel and it can be retarded through many approaches including electrodeposition of inert inhibitors in the form of organic molecules. Salicylideneaniline (L1) and 4-hydroxybenzalaniline (L2) were electrodeposited on mild steel using cyclic voltammetry (CV) using 0.1 M inhibitor concentration in 0.3 M NaOH. The scanning potential range for coating via CV was set from 0 - 2 V and back to 0 V for five cycles. A yellow film was observed covering the surface of the mild steel. The corrosion behavior of coated and uncoated mild steel was studied using Linear Polarization Resistance (LPR) in 0.5 M NaCl. Both coated mild steel specimens showed better corrosion resistance than the uncoated, with L1 providing a better inhibition protection with the inhibition efficiency of 80.51 %.

  9. Manufacture of tube billets for fuel cans by vacuum centrifugal casting

    International Nuclear Information System (INIS)

    Zelenskij, V.F.; Neklyudov, I.M.; Chernyj, B.P.

    1989-01-01

    Vacuum device for induction melting with centrifugal casting in the ingot mold with rotation vertical or horisontal axis is presented. Removing and grinding of nonmetallic inclusions are realized by selection of casting conditions and of chemically active reducer, sound metal with high ductility is obtained. Data on micro- and macrostructure of casted tube billets made of 08Kh18N10T and 06Kh16H15M3B stainless steels, designed for manufacture of fuel cans are presented

  10. Automation of ultrasonic testing of turbine disk billets

    International Nuclear Information System (INIS)

    Gorodkov, V.E.; Domashevskij, B.N.; Pron', N.I.; Tkachenko, V.A.

    1984-01-01

    cations of ultrasonic facility for automation of testing turbine disk billets of 25Kh2PMFA and 34KhM1A steels are considered. The operating principle and the design of ''Disk-1'' facility are described, its test results are presented. It is shown that the facility increases the test efficiency five times, enables to estimate dimensions of revealed defect with regard to the quality of acoustic contact, thus facilitating the work of personnel and improving the test quality

  11. Friction stir processing on high carbon steel U12

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-10-27

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

  12. Electrochemical studies of novel corrosion inhibitor for mild steel in 1 M hydrochloric acid

    Directory of Open Access Journals (Sweden)

    Ahmed A. Al-Amiery

    2018-06-01

    Full Text Available The electrochemical performance of a novel organic corrosion inhibitor 6-(4-hydroxyphenyl-3-mercapto-7,8-dihydro-[1,2,4]triazolo[4,3-b][1,2,4,5]tetrazine [HT3], for mild steel in 1 M hydrochloric acid is evaluated by potentiodynamic curves. The experimental results show that the investigated inhibitor [HT3], which can effectively retard the corrosion process that occurs to mild steel with a hydrochloric acid solution by providing a protective coating for the mild steel that, can be weakened by increasing the temperature. Furthermore, the inhibition efficiency of [HT3] increased with increasing the concentrations of the inhibitors and decreased with increasing temperature. Keywords: Corrosion, Inhibitor, Mild steel, Potentiodynamic polarization, HT3, NMR, FT-IR

  13. Creep cavity and carbide studies during creep of a 12%CrMoV-steel

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Henrik; Storesund, J.; Seitisleam, F.

    1997-03-01

    Uniaxial creep tests of a X20CrMoV 12 1 steel has been carried out. The work was performed as a follow-up on earlier investigations on a similar steel with lower creep ductility. A comparison with this previous work is included. Both interrupted and rupture tests were performed and studies were made of cavity formation processes and carbide transformations. The creep curves could be reproduced using an analytical model. No secondary creep was observed. Cavities were found to form already at a strain of 1%. The cavity density, mean diameter and cavitated area fraction were found to have a linear relationship with the strain for strains up to about 10%. The mean carbide diameter was observed to be a function of time at temperature. A small decrease in carbide density with strain was detected 12 refs, 28 figs, 6 tabs

  14. 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

  15. The effect of sulphite on crevice corrosion and pitting on various steels in 0.5 M sodium chloride

    International Nuclear Information System (INIS)

    Hemmingsen, T.; Nielsen, L.V.; Maahn, E.

    1992-01-01

    A carbon steel, st 37, and two stainless steels, AISI 304 SS and AISI 316 SS were exposed to 0.5 M NaCl with 10 mM sulphite under anaerobic conditions. The sulphite ions may, under these conditions, be reduced to sulphide ions, and cause pitting or crevice corrosion. Electrochemical and bottle-test experiments were done to determine the effect of the sulphite addition. These effects were highly dependant on the pH

  16. Static Recrystallization Behavior of Z12CN13 Martensite Stainless Steel

    Science.gov (United States)

    Luo, Min; Zhou, Bing; Li, Rong-bin; Xu, Chun; Guo, Yan-hui

    2017-09-01

    In order to increase the hot workability and provide proper hot forming parameters of forging Z12CN13 martensite stainless steel for the simulation and production, the static recrystallization behavior has been studied by double-pass hot compression tests. The effects of deformation temperature, strain rate and inter-pass time on the static recrystallization fraction by the 2% offset method are extensively studied. The results indicate that increasing the inter-pass time and the deformation temperature as well as strain rate appropriately can increase the fraction of static recrystallization. At the temperature of 1050-1150 °C, inter-pass time of 30-100 s and strain rate of 0.1-5 s-1, the static recrystallization behavior is obvious. In addition, the kinetics of static recrystallization behavior of Z12CN13 steel has been established and the activation energy of static recrystallization is 173.030 kJ/mol. The substructure and precipitates have been studied by TEM. The results reveal that the nucleation mode is bulging at grain boundary. Undissolved precipitates such as MoNi3 and Fe3C have a retarding effect on the recrystallization kinetics. The effect is weaker than the accelerating effect of deformation temperature.

  17. High Strength-High Ductility Combination Ultrafine-Grained Dual-Phase Steels Through Introduction of High Degree of Strain at Room Temperature Followed by Ultrarapid Heating During Continuous Annealing of a Nb-Microalloyed Steel

    Science.gov (United States)

    Deng, Yonggang; Di, Hongshuang; Hu, Meiyuan; Zhang, Jiecen; Misra, R. D. K.

    2017-07-01

    Ultrafine-grained dual-phase (UFG-DP) steel consisting of ferrite (1.2 μm) and martensite (1 μm) was uniquely processed via combination of hot rolling, cold rolling and continuous annealing of a low-carbon Nb-microalloyed steel. Room temperature tensile properties were evaluated and fracture mechanisms studied and compared to the coarse-grained (CG) counterpart. In contrast to the CG-DP steel, UFG-DP had 12.7% higher ultimate tensile strength and 10.7% greater uniform elongation. This is partly attributed to the increase in the initial strain-hardening rate, decrease in nanohardness ratio of martensite and ferrite. Moreover, a decreasing number of ferrite grains with {001} orientation increased the cleavage fracture stress and increased the crack initiation threshold stress with consequent improvement in ductility UFG-DP steel.

  18. Corrosion of an Fe-12 Cr-1 Mo VW steel in thermally-convective lithium

    International Nuclear Information System (INIS)

    Tortorelli, P.F.; DeVan, J.H.

    1983-01-01

    A thermal-convection loop of Fe-12 Cr-1 Mo VW steel circulated pure lithium between 500 and 350 0 C for 10,088 h. Periodic weighings of coupons at different temperatures around the loop revealed small weight losses and corrosion rates. Surface analysis showed a relatively thin corrosion layer with an underlying carbide-free zone and some depletion of chromium from the hottest specimen. While some mass transfer of chromium and nickel was detected, this mechanism did not strongly influence the weight loss process as it does with austenitic steels. Therefore, it appeared that reactions with carbon and nitrogen must be the dominant corrosion processes such that weight loss was maximized at the lowest temperature (350 0 C). Overall, the lithium-steel reactions in the temperature range of this experiment were relatively sluggish and the corrosion was not severe

  19. Kankaan tuotekehittäminen erikoisolosuhteisiin K&H Annala Oy:lle

    OpenAIRE

    Koski, Marjo

    2017-01-01

    Opinnäytetyö tehtiin yhteistyössä Suomen ainoan huonekalukankaita valmistavan yrityksen K&H Annala Oy:n kanssa. Työn aiheena oli suunnitella ja tuotteistaa kangasmallisto erikoisolosuhteisiin innovatiivisesta, Italiassa valmistettavasta Flyer-langasta. Projektin lähtökohtana oli opinnäytetyöntekijän kasvava kiinnostuneisuus kudottuja tekstiilejä kohtaan ja kankaan suunnitteluprosessin vieminen teollisen tuotannon puolelle. Projektissa tähdättiin uudentyyppiseen kankaaseen ilmeen ja materiaali...

  20. On the problem of safe usage of 12MKh steel at elevated temperatures and high hydrogen pressures

    International Nuclear Information System (INIS)

    Archakov, Yu.I.; Teslya, B.M.

    1982-01-01

    The behaviour of the 12MKh steel in hydrogen at pressures of 4-100 MPa and temperatures of 450-600 deg C has been investigated to study the regularities of hydrogen corrosion process. The samples are held in hydrogen under all-round compression in autoclaves with subsequent determination of mechanical properties, carbon content and microstructure. Dependencies of time to begining of intensive embrittlement under given conditions are found. The empiric equation for the calculation of time to beginning of hydrogen corrosion is derived, the safe usage of the 12MKh steel at different temperatures and pressures are determined

  1. Susceptibility to stress corrosion in stainless steels type AISI 321 and 12X18H10T used in PWR type reactors (WWER)

    International Nuclear Information System (INIS)

    Matadamas C, N.

    1995-01-01

    Titanium stabilized stainless steels have been utilized in sovietic pressurized water reactors (VVER) for avoid the susceptibility to Intergranular Corrosion (IGC) present in other austenitic stainless steels. However the Intergranular Corrosion resistance of this kind of materials has been questioned because of Intergranular Stress Corrosion Cracking failures (IGSCC) have been reported. This paper study the electrochemical behavior of the AISI 321 stainless steel in a H 3 BO 3 Solution contaminated with chlorides and its susceptibility to Intergranular Corrosion.Electrochemical prediction diagrams of the stainless steels AISI 321 and 12X18H10T (sovietic) sensitized (600 Centigrade, 3 h.) were compared. Cylindrical and conical samples were used in Slow Strain Rate Tests (SSRT), to determine the susceptibility to Stress Corrosion Cracking (SCC) in AISI 321 and 12X18H10T stainless steels. The results obtained showed that the temperature of the solution is a very important factor to detect this susceptibility. Fractography studies on the fracture surfaces of the samples obtained in the SSRT at high temperature were realized. Corrosion velocities of both AISI 321 and 12X18H10T stainless steels were determined using conical samples in the CERT system at high temperature. E.D.A.X. analysis was employed in both AISI 321 and 12X18H10T stainless steels in order to explain the degree of sensitization. (Author)

  2. Improved hardness of laser alloyed X12CrNiMo martensitic stainless steel

    CSIR Research Space (South Africa)

    Adebiyi, DI

    2011-07-01

    Full Text Available The improvement in hardness of X12CrNiMo martensitic stainless steel laser alloyed with 99.9% pure titanium carbide, stellite 6 and two cases of premixed ratio of titanium carbide and stellite 6 [TiC (30 wt.%)- stellite 6 (70 wt.%) and TiC (70 wt...

  3. Influence of ausaging on microstructure and mechanical properties of high nitrogen 12% Cr steel for power plant applications

    International Nuclear Information System (INIS)

    Dymek, S.; Blicharski, M.

    2004-01-01

    The paper presents an investigation of a martensitic high-nitrogen steel with 12% Cr content designed for potential applications in power plants. The steel was subjected to ausaging before martensitic transformation or ausaging by tempering. The ausaging influenced greatly the precipitation reactions as well as yield strength at elevated temperatures. It was dissolution and reprecipitation of MN-type vanadium nitrides with a face-centered cubic crystal structure which controlled the dispersion of precipitates and thus mechanical properties of the steel. (author)

  4. Changes in mechanical properties and structure of electrolytic plasma treated X 12 CrNi 18 10 Ti stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Kurbanbekov, Sherzod; Baklanov, Viktor; Karakozov, Batyrzhan [Republican State Enterprise National Nuclear Center of Kazakhstan, Kurchatov (Kazakhstan). Inst. of Atomic Energy Branch; Skakov, Mazhyn [Republican State Enterprise National Nuclear Center of Kazakhstan, Kurchatov (Kazakhstan)

    2017-05-01

    The paper addresses findings regarding the influence of electrolytic plasma treatment on the mechanical properties as well as structural and phase states of X 12 CrNi 18 10 Ti steel. Electrolytic plasma treatment is based on carburizing of stainless steel heated in electrolytes. Treatment of steel samples has been performed as follows: the samples were heated up to a temperature between 850 and 950 C and then they were cured for 7 minutes in an electrolyte of an aqueous solution containing 10 % glycerol (C{sub 3}H{sub 8}O{sub 3}) and 15 % sodium carbonate (Na{sub 2}CO{sub 3}). It is found that, after plasma electrolytic treatment, the surface of X 12 CrNi 18 10 Ti steel had a modified structure and high hardness. Increasing wear resistance of X 12 CrNi 18 10 Ti steel has been observed after carburizing and the coefficient of friction has been reduced. X-ray analysis showed that retained austenite γ-Fe is a main phase, and there are some diffraction lines of orthorhombic Fe{sub 3}C phase as well as Fe{sub 3}O{sub 4} cubic phase. It has been determined, that, after plasma electrolytic treatment, a carbide phase in the modified surface layer, irrespective of the location in the steel structure has the chemical composition Fe{sub 3}C. High concentration of carbon atoms in a solid solution based on γ- and α-iron, a large dislocation density, presence of particles of carbide phase and retained austenite layers have been found.

  5. Alfinated coating structure on HS6-5-2 (SW7M high speed steel

    Directory of Open Access Journals (Sweden)

    T. Szymczak

    2010-10-01

    Full Text Available The paper presents the results of immersion alfinated coating structure in AlSi5 silumin on HS6-5-2 (SW7M high speed steel. Alfinating bath temperature was 750 ± 5 ° C, time of sample immersion was τ = 180s. Thickness of obtained coating under specified conditions was g = 150μm. Manufactured coating consists of three layers of different construction phase. The first layer from the substrate „g1`” constructed with a AlFe phase consist of alloy additives constituents of HS6-5-2 (SW7M steel: W, Mo, V, Cr and Si. On it crystallizes the second layer „g1``” of AlFeWMoCr intermetallic phases also containing Si and small amount of V. Last, the outer layer „g2” of the coating is composed with silumin including AlFeWMoCrVSi intermetallic phases. Within all layers of the coating occurs carbides. Penetration of carbides to individual coating layers is mainly due to steel surface partial melting and crystallizing layers „g1`” and „g1``” by alfinating liquid and shifting into her of carbides as well as partial carbides rejection by crystallization front of intermetallic phases occurs in coating.

  6. Fabrication of welded pipes of the KhN45Yu alloy

    International Nuclear Information System (INIS)

    Lyapunov, A.I.; Krichevskij, E.M.; L'vov, V.N.; Kozlov, N.N.; Kireeva, T.S.

    1977-01-01

    A highly heat-resistant KhN45Yu (EP 747) alloy has been developed; the alloy is designed to withstand prolonged service in the temperature range of 1000-1300 deg C, or short-term service at 1300-1400 deg C. The satisfactory ductility and good weldability of the alloy have made it possible to obtain sheets and pipes (32 x 2.0 mm) by argon arc welding. The ductility of pipes from EP 747 alloy exceeds that of pipes from KhN78T (EI 435) alloy by 5.10%, the strength being approximately equal. In regard to strength the welded joint differs little from the base metal. The ductility characteristics up to 900 deg C are also equal, since failure occurs in the base metal. At higher temperatures the welded joint fails in the metal of the weld, and its ductility drops sharply. The grain size of the base metal corresponds to No. 3-4. The welded joint has a cast structure with a grain size larger than No. 1, but its ductility characteristics are satisfactory. This structure ensures an increased long-term strength of the material at 1000-1200 deg C

  7. Metodologi Fatwa K.H. Muhammad Syaf’i Hadzami

    Directory of Open Access Journals (Sweden)

    Muhammad Ardiansyah

    2018-01-01

    Full Text Available Fatwa is one of the heavy mandates on the shoulders of Moslem scholars. There are some conditions that must be fulflled before the fatwa could be used to solve the problems of the people. Basically, the fatwa replaces the task of the Prophet in conveying the shari’a law, then the scholars did not dare to be reckless in declaring any fatwa. Therefore, being a mufti is not only required by reading the translation of al-Qur’an or Hadith, or by searching on the google, or by copying broadcasts in social media. According to al-Shirazi, the intellectual condition that must be required to be a mufti is deep understanding toward al-Qur’an and Hadith, also understanding sources of speech such as ḥaqîqah-majâz, ‘âmm-khâṣṣ, Arabic language, nâsikh-mansûkh, ijmâ’, ikhtilaf, and tartîb al-adillah. While the moral requirements to be a mufti according to Imam Ahmad bin Hanbal are having pure intention, having broad knowledge, patience, and soul, having strong mentality to fulfl the task, having suffciency of life to avoid being influenced by others, and understanding the condition of society. This paper attempts to examine the fatwas of a mufti from Betawi who had lived in the modern era known as Mu’allim Syaf’i Hadzami. The fatwas were collected in a work entitled Tawḍîḥ al-Adillah. In this article, the author has concluded that Mu’allim uses eight complementary and relevant fatwa methodologies to solve today’s problems

  8. Mitigation of sensitisation effects in unstabilised 12%Cr ferritic stainless steel welds

    International Nuclear Information System (INIS)

    Warmelo, Martin van; Nolan, David; Norrish, John

    2007-01-01

    Sensitisation in the heat-affected zones of ferritic stainless steel welds is typically prevented by stabilisation of the parent material with titanium or niobium, and suitable design of the overall composition to produce a suitably high ferrite factor. However, such alloy modification has proven to be economically unviable for thick gauge (>10 mm) plate products and therefore unstabilised 12%Cr (3CR12) material is still currently being used for heavy gauge structural applications in many parts of the world. The aim of the current work was to review the mechanisms responsible for sensitisation in these unstabilised ferritic stainless steels, and to characterise the sensitisation effects arising from multipass welding procedures. The objective was to determine the influence of welding parameters, and thereby to recommend mitigating strategies. Two particular sensitisation modes were found to occur in the current work, although only one was predominant and considered problematic from a practical perspective. It was found that with proper positioning of weld capping runs and control of weld overlap, it is possible to ensure that sensitising isotherms remain buried beneath the parent surface, and so reduce harmful corrosion effects

  9. Conversion of MX nitrides to Z-phase in a martensitic 12% Cr steel

    DEFF Research Database (Denmark)

    Cipolla, L.; Danielsen, Hilmar Kjartansson; Venditti, D.

    2010-01-01

    A 12% Cr model steel was designed with the purpose of studying the nucleation and growth of modified Z-phase, Cr(V,Nb)N. The model alloy develops Z-phase after relatively short ageing times and contains only nitrides of Cr, V and Nb. Interferences from the presence of carbides and the development...

  10. MTS-MD of Biomolecules Steered with 3D-RISM-KH Mean Solvation Forces Accelerated with Generalized Solvation Force Extrapolation.

    Science.gov (United States)

    Omelyan, Igor; Kovalenko, Andriy

    2015-04-14

    We developed a generalized solvation force extrapolation (GSFE) approach to speed up multiple time step molecular dynamics (MTS-MD) of biomolecules steered with mean solvation forces obtained from the 3D-RISM-KH molecular theory of solvation (three-dimensional reference interaction site model with the Kovalenko-Hirata closure). GSFE is based on a set of techniques including the non-Eckart-like transformation of coordinate space separately for each solute atom, extension of the force-coordinate pair basis set followed by selection of the best subset, balancing the normal equations by modified least-squares minimization of deviations, and incremental increase of outer time step in motion integration. Mean solvation forces acting on the biomolecule atoms in conformations at successive inner time steps are extrapolated using a relatively small number of best (closest) solute atomic coordinates and corresponding mean solvation forces obtained at previous outer time steps by converging the 3D-RISM-KH integral equations. The MTS-MD evolution steered with GSFE of 3D-RISM-KH mean solvation forces is efficiently stabilized with our optimized isokinetic Nosé-Hoover chain (OIN) thermostat. We validated the hybrid MTS-MD/OIN/GSFE/3D-RISM-KH integrator on solvated organic and biomolecules of different stiffness and complexity: asphaltene dimer in toluene solvent, hydrated alanine dipeptide, miniprotein 1L2Y, and protein G. The GSFE accuracy and the OIN efficiency allowed us to enlarge outer time steps up to huge values of 1-4 ps while accurately reproducing conformational properties. Quasidynamics steered with 3D-RISM-KH mean solvation forces achieves time scale compression of conformational changes coupled with solvent exchange, resulting in further significant acceleration of protein conformational sampling with respect to real time dynamics. Overall, this provided a 50- to 1000-fold effective speedup of conformational sampling for these systems, compared to conventional MD

  11. Kinetics and mechanism of oxidation of carbidized electrolytic chromium coatings

    International Nuclear Information System (INIS)

    Arkharov, V.I.; Yar-Mukhamedov, Sh.Kh.

    1978-01-01

    Thermal stability carbidized electrolytic chromium coatings has been studied depending on the conditions of their formation; the specific features of the mechanism of oxidation at 1200 deg in an air atmosphere have been elucidated. It has been established that kinetics of high temperature oxidation of the coatings depends essentially on the conditions of their formation and on the composition of steel to which the coating is applied. It has been shown that two oxidation mechanisms are possible: by diffusion of the residual chromium through a carbide layer along the carbide grain boundaries outwards or, when there is no residual chromium, by chemical reaction of carbon combustion and oxidation of the liberated chromium. The comparison of oxidation kinetic curves of the samples of 38KhMYuA, 35KhGSA, and DI-22 steels with and without coating has shown that the coatings under study have a better protective effect on 38KhMYuA steel than on 35KhGSA, although without coating oxidability of the first steel is higher than that of the second

  12. Octanol-Water Partition Coefficient from 3D-RISM-KH Molecular Theory of Solvation with Partial Molar Volume Correction.

    Science.gov (United States)

    Huang, WenJuan; Blinov, Nikolay; Kovalenko, Andriy

    2015-04-30

    The octanol-water partition coefficient is an important physical-chemical characteristic widely used to describe hydrophobic/hydrophilic properties of chemical compounds. The partition coefficient is related to the transfer free energy of a compound from water to octanol. Here, we introduce a new protocol for prediction of the partition coefficient based on the statistical-mechanical, 3D-RISM-KH molecular theory of solvation. It was shown recently that with the compound-solvent correlation functions obtained from the 3D-RISM-KH molecular theory of solvation, the free energy functional supplemented with the correction linearly related to the partial molar volume obtained from the Kirkwood-Buff/3D-RISM theory, also called the "universal correction" (UC), provides accurate prediction of the hydration free energy of small compounds, compared to explicit solvent molecular dynamics [ Palmer , D. S. ; J. Phys.: Condens. Matter 2010 , 22 , 492101 ]. Here we report that with the UC reparametrized accordingly this theory also provides an excellent agreement with the experimental data for the solvation free energy in nonpolar solvent (1-octanol) and so accurately predicts the octanol-water partition coefficient. The performance of the Kovalenko-Hirata (KH) and Gaussian fluctuation (GF) functionals of the solvation free energy, with and without UC, is tested on a large library of small compounds with diverse functional groups. The best agreement with the experimental data for octanol-water partition coefficients is obtained with the KH-UC solvation free energy functional.

  13. Inhibitor effect on corrosion of titanium alloys in muriatic solutions of titanium-magnesium production

    International Nuclear Information System (INIS)

    Dobrunov, Yu.V.; Volynskij, V.V.; Kolobov, G.A.; Kuznetsov, S.I.

    1977-01-01

    Corrosion tests of titanium alloys VTI-0, OT4, VT5-1 and steel Kh18N1OT in 10% and 18% HCl with additions of carnallite at 40 deg C have been carried out. It has been established that titanium alloys in 10% and 18% HCl containing 5 and 10% carnallite are sufficiently corrosion resistant in the presence of 0.1-1% FeCl or HNO 3 and can be used for manufacturing the equipment of recirculation gas scrubbers. Steel Kh18N10T is unstable in all the media tested. It is subjected to intensive pitting. Specimens of steel Kh18N10T have also revealed edge cracking

  14. Effect of heating and deformation conditions on the depth of surface defects in alloyed steel rolling

    International Nuclear Information System (INIS)

    Malygin, R.Z.; Karyakin, B.P.; Grosman, A.B.; Simovskikh, V.N.; Storozhev, V.I.

    1978-01-01

    The effect of heating and deformation conditions on the depth change of artificial defects in the 50 KhFA alloyed steel rolling on the 850 blooming and 450 section mill was studied. Quite a definite regularity in the arrangement of defects (cracks and hairlines) along the circumference of the round steel bar and obvious relation with the defect distribution on the bloom faces are established. Oxidation is shown to diminish defect depth while ingot and billet heating especially on the faces under direct firing. Blooms should be placed in the furnace with 90 deg canting in relation to the faces position while ingot heating. Round rolling must be performed with one or several 45 deg strip cantings. The defect depth for the ingots to be rolled without chipping is set up

  15. Investigations on the growth kinetics of Laves phase precipitates in 12% Cr creep-resistant steels: Experimental and DICTRA calculations

    Energy Technology Data Exchange (ETDEWEB)

    Prat, O. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany)] [Universidad de Concepcion, Departamento de Ingenieria de Materiales, Edmundo Larenas 270, Concepcion (Chile); Garcia, J., E-mail: jose.garcia@helmholtz-berlin.de [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Rojas, D. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany); Carrasco, C. [Universidad de Concepcion, Departamento de Ingenieria de Materiales, Edmundo Larenas 270, Concepcion (Chile); Inden, G. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany)

    2010-10-15

    The growth kinetics of Laves phase precipitates (type Fe{sub 2}W) in the early stage of creep (650 deg. C for 10,000 h) in two 12% Cr ferrite-martensitic steels has been investigated. In one alloy the Laves phase formed on tempering, while in the second alloy the Laves phase precipitated during creep. Kinetic simulations were performed using the software DICTRA. The particle size of the Laves phase was measured on transmission electron microscopy samples. The equilibrium phase fraction of the Laves phase was reached in the first thousand hours. Simulations of particle growth showed good agreement with the experimental results. Competitive growth between M{sub 23}C{sub 6} and the Laves phase showed that M{sub 23}C{sub 6} carbides reached their equilibrium after 12 days, whereas the Laves phase reached equilibrium after 3 months. Simulations of the influence of the interfacial energy and addition of Co, Cu and Si on Laves phase precipitation are presented.

  16. Investigations on the growth kinetics of Laves phase precipitates in 12% Cr creep-resistant steels: Experimental and DICTRA calculations

    International Nuclear Information System (INIS)

    Prat, O.; Garcia, J.; Rojas, D.; Carrasco, C.; Inden, G.

    2010-01-01

    The growth kinetics of Laves phase precipitates (type Fe 2 W) in the early stage of creep (650 deg. C for 10,000 h) in two 12% Cr ferrite-martensitic steels has been investigated. In one alloy the Laves phase formed on tempering, while in the second alloy the Laves phase precipitated during creep. Kinetic simulations were performed using the software DICTRA. The particle size of the Laves phase was measured on transmission electron microscopy samples. The equilibrium phase fraction of the Laves phase was reached in the first thousand hours. Simulations of particle growth showed good agreement with the experimental results. Competitive growth between M 23 C 6 and the Laves phase showed that M 23 C 6 carbides reached their equilibrium after 12 days, whereas the Laves phase reached equilibrium after 3 months. Simulations of the influence of the interfacial energy and addition of Co, Cu and Si on Laves phase precipitation are presented.

  17. Microstructure and creep properties of 9-12 % Cr-steels. The influence of Co

    Energy Technology Data Exchange (ETDEWEB)

    Kauffmann, F.; Zies, G.; Maile, K. [Stuttgart Univ. (Germany). MPA; Straub, S. [ALSTOM Power Systems, Mannheim (Germany); Mayer, K.H. [ALSTOM Power System, Nuernberg (Germany)

    2008-07-01

    The martensitic 9-12 wt. % Cr steels currently developed for the application in steam power plants are aimed for service temperatures above 600 C and steam pressures above 250 bar. The creep strength of these steels strongly depends on the microstructure and thereby on the chemical composition. In the present work, a combination of various microscopy techniques is used to study the microstructural changes of creep relevant features like subgrain-size, dislocation density, the chemical composition and crystallographic structure of the occurring precipitates as well as their density and size distribution in dependence of the addition of Co for several steels developed in the frame of the COST programs. These features are then correlated with the creep strength of the materials. The behavior of the alloy CB6 with a high Co content is compared to the low Co containing CB2 and the Co free B0 at 650 C. Similar comparisons are made for the alloy FN2, FN3 and FN 4 at 600 C. (orig.)

  18. Gas Furnace with Pulsed Feeding of the Heating Agent for Volume Precision Heat Treatment of CCM Rolls

    Science.gov (United States)

    Moroz, V. I.; Egorova, V. M.; Gusev, S. V.

    2001-05-01

    A standard chamber batch furnace of the Severstal' plant has been modified for precision heat treatment of CCM rolls. The certification tests of a charge of rolls from steel 24KhM1F have shown the technical and economical advantages of the new design.

  19. Practical domain for ultrasonic testing of stainless steel over plain carbon steel layered components using M21 waves

    International Nuclear Information System (INIS)

    Grewal, D.S.; Bray, D.E.

    1995-01-01

    The first higher order mode of the Rayleigh wave was discussed by Sezawa in the early part of this century in context of seismological wave studies. These Sezawa, or M 21 , or first higher order mode Rayleigh waves, have subsequently been used in the field of nondestructive testing of layered materials based on the development of the seismological model of the Sezawa waves by others. In this paper the study of the Tiersten formulation in context with slow speed over high speed materials, e.g. stainless steel overlay on plain carbon steel, the limitations and applicability of that formulation is reported. This study illustrates the practical bounds for testing such layered media, using numerical analysis of this formulation for the first higher-order mode to establish theoretical limits, and corroboration of these bounds by experimental results

  20. Mechanical Suppression of SCC and Corrosion Fatigue Failures in 300M Steel Landing Gear

    National Research Council Canada - National Science Library

    Prevey, Paul; Jayaraman, N; Ontko, Neal; Shepard, Mike; Ware, Robert; Coate, Jack

    2004-01-01

    300M steel is widely used in landing gear because of its ultra high strength with high fracture toughness, but is vulnerable to both corrosion fatigue and stress corrosion cracking, with potentially...

  1. Corrosion resistance of metals and alloys in molten alkalies

    International Nuclear Information System (INIS)

    Zarubitskij, O.G.; Dmitruk, B.F.; Minets, L.A.

    1979-01-01

    Literature data on the corrosion of non-ferrous and noble metals, iron and steels in the molten alkalis and mixtures of their base are presented. It is shown that zirconium, niobium and tantalum are characterized by high corrosion stability in the molten NaOH. Additions of NaOH and KOH to the alkali chloride melts result in a 1000 time decrease of zirconium corrosion rate at 850 deg. The data testify to the characteristic passivating properties of OH - ions; Mo and W do not possess an ability to selfpassivation in hydroxide melts. Corrosion resistance of carbon and chromium-nickel steels in hydroxide melts depends considerably on the temperature, electrolyte composition and atmosphere over them. At the temperatures up to 600 deg C chromium-nickel steel is corrosion resistant in the molten alkali only in the inert atmosphere. Corrosion rate of chromium-nickel alloy is the lower the less chromium and the more nickel it contains. For the small installations the 4Kh18N25S2 and Kh23N28M3D3T steels can be recommended

  2. Functional characterization of a wheat NHX antiporter gene TaNHX2 that encodes a K(+/H(+ exchanger.

    Directory of Open Access Journals (Sweden)

    Yuanyuan Xu

    Full Text Available The subcellular localization of a wheat NHX antiporter, TaNHX2, was studied in Arabidopsis protoplasts, and its function was evaluated using Saccharomyces cerevisiae as a heterologous expression system. Fluorescence patterns of TaNHX2-GFP fusion protein in Arabidopsis cells indicated that TaNHX2 localized at endomembranes. TaNHX2 has significant sequence homology to NHX sodium exchangers from Arabidopsis, is abundant in roots and leaves and is induced by salt or dehydration treatments. Western blot analysis showed that TaNHX2 could be expressed in transgenic yeast cells. Expressed TaNHX2 protein suppressed the salt sensitivity of a yeast mutant strain by increasing its K(+ content when exposed to salt stress. TaNHX2 also increased the tolerance of the strain to potassium stress. However, the expression of TaNHX2 did not affect the sodium concentration in transgenic cells. Western blot analysis for tonoplast proteins indicated that the TaNHX2 protein localized at the tonoplast of transgenic yeast cells. The tonoplast vesicles from transgenic yeast cells displayed enhanced K(+/H(+ exchange activity but very little Na(+/H(+ exchange compared with controls transformed with the empty vector; Na(+/H(+ exchange was not detected with concentrations of less than 37.5 mM Na(+ in the reaction medium. Our data suggest that TaNHX2 is a endomembrane-bound protein and may primarily function as a K(+/H(+ antiporter, which is involved in cellular pH regulation and potassium nutrition under normal conditions. Under saline conditions, the protein mediates resistance to salt stress through the intracellular compartmentalization of potassium to regulate cellular pH and K(+ homeostasis.

  3. Sigma phases in an 11%Cr ferritic/martensitic steel with the normalized and tempered condition

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Yinzhong, E-mail: shenyz@sjtu.edu.cn [School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Zhou, Xiaoling; Shi, Tiantian; Huang, Xi [School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Shang, Zhongxia [School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Liu, Wenwen; Ji, Bo; Xu, Zhiqiang [School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)

    2016-12-15

    At the present time 9–12% Cr ferritic/martensitic (F/M) steels with target operating temperatures up to 650 °C and higher are being developed in order to further increase thermal efficiency so as to reduce coal consumption and air pollution. An 11% Cr F/M steel was prepared by reference to the nominal chemical composition of SAVE12 steel with an expected maximum use temperature of 650 °C. The precipitate phases of the 11% Cr F/M steel normalized at 1050 °C for 0.5 h and tempered at 780 °C for 1.5 h were investigated by transmission electron microscopy. Except for Cr-/Cr-Fe-Co-rich M{sub 23}C{sub 6}, Nb-/V-/Ta-Nb-/Nd-rich MX, Fe-rich M{sub 5}C{sub 2}, Co-rich M{sub 3}C and Fe-Co-rich M{sub 6}C phases previously identified in the steel, two types of sigma phases consisting of σ-FeCr and σ-FeCrW were found to be also present in the normalized and tempered steel. Identified σ-FeCr and σ-FeCrW phases have a simple tetragonal crystal structure with estimated lattice parameters a/c = 0.8713/0.4986 and 0.9119/0.5053 nm, respectively. The compositions in atomic pct of the observed sigma phases were determined to be approximately 50Fe-50Cr for the σ-FeCr, and 30Fe-55Cr-10W in addition to a small amount of Ta, Co and Mn for the σ-FeCrW. The sigma phases in the steel exhibit various blocky morphologies, and appear to have a smaller amount compared with the dominant phases Cr-rich M{sub 23}C{sub 6} and Nb-/V-/Ta-Nb-rich MX of the steel. The σ-FeCr phase in the steel was found to precipitate at δ-ferrite/martensite boundaries, suggesting that δ-ferrite may rapidly induce the formation of sigma phase at δ-ferrite/martensite boundaries in high Cr F/M steels containing δ-ferrite. The formation mechanism of sigma phases in the steel is also discussed in terms of the presence of δ-ferrite, M{sub 23}C{sub 6} precipitation, precipitation/dissolution of M{sub 2}X, and steel composition. - Highlights: •Precipitate phases in normalized and tempered 11%Cr F/M steel are

  4. The influence of welding and post heat treatment parameters on the diffusion and precipitation processes in dissimilar metal joints of a 1% and a 12% Cr-steel

    International Nuclear Information System (INIS)

    Kullik, M.; Katerbau, K.H.

    1989-05-01

    The influences of different weld metals, welding processes and post weld heat treatments (PWHT) on mechanical properties, carbon diffusion and precipitation processes were investigated by studying dissimilar metal welds between the cast steel GS-17 CrMoV 5 11 (1% Cr) and the steel X 20 CrMoV 12 1 (12% Cr). By means of tensile and impact tests, metallographic investigation, hardness measurements, electron beam X-ray microanalysis and transmission electron microscope examination changes in the welded joints were shown after different PWHT's as well as after creep tests. It was found that the joint with a 5% CrMoV-weld metal shows higher yield and rupture strength than the joint with a 12% CrMoV-weld metal. With increasing heat input during PWHT the strength decreases for both welds, but always remains higher than the values of the base materials. During PWTH as well as during service at elevated temperatures carbon diffuses from the lower chromium material to the higher chromium material. Width and carbon concentration of the carburized and decarburized zones depend on the heat input. A simple diffusion model was developed to describe the carbon profile for any annealing time and temperature. The consequence of the decarburization is a microstructural change in the heat effected zone of the cast steel. During longer annealing the fine M 2 C-carbides dissolve and coarse M 6 C-crbides form, resulting in a lower creep ductility of this zone. (orig.) With 19 refs., 15 tabs., 104 figs [de

  5. Irradiation behavior evaluation of oxide dispersion strengthened ferritic steel cladding tubes irradiated in JOYO

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Shinichiro, E-mail: yamashita.shinichiro@jaea.go.jp; Yano, Yasuhide; Ohtsuka, Satoshi; Yoshitake, Tsunemitsu; Kaito, Takeji; Koyama, Shin-ichi; Tanaka, Kenya

    2013-11-15

    Irradiation behavior of ODS steel cladding tubes was evaluated for the further progress in understanding of the neutron-irradiation effects on ODS steel. Two types of ODS (9Cr–ODS{sub F}/M, 12Cr–ODS{sub F}) steel cladding tubes with differences in basic compositions and matrix phases were irradiated in JOYO. Post-irradiation examination data concerning hardness, ring tensile property, and microstructure were obtained. Hardness measurement after irradiation showed that there was an apparent irradiation temperature dependence on hardness for 9Cr–ODS{sub F}/M steel whereas no distinct temperature dependence for 12Cr–ODS{sub F} steel. Also, there was no significant change in tensile strengths after irradiation below 923 K, but those above 1023 K up to 6.6 × 10{sup 26} n/m{sup 2} (E > 0.1 MeV) were decreased by about 20%. TEM observations showed that the radiation-induced defect cluster formation during irradiation was suppressed because of high density sink site for defect such as initially-existed dislocation, and precipitate interfaces. In addition, oxide particles were stable up to the maximum doses of this irradiation test.

  6. Reliability of non-heated tube bends of boilers

    International Nuclear Information System (INIS)

    Bugaj, N.V.; Akhremenko, V.L.; Zamotaev, V.S.

    1984-01-01

    Bend failures are described for non-heated boiler tubes of 12Kh1MF and 20 steels. Methods of reliability evaluations are presented which permit revealing and replacing the bends with inadequate resources. Influences of operation conditions on bend durability is shown as well as the factors which are dominating at bend failures

  7. V and Nb Influence on the Austenitic Stainless Steel Corrosion in 0.1 M HCl

    Directory of Open Access Journals (Sweden)

    Amel GHARBI

    2014-05-01

    Full Text Available Vanadium and niobium were added in AISI309 austenitic stainless steel composition to modify their structure and pitting corrosion resistance in 0.1 M HCl. The structural characterization was carried out by X-rays diffraction and optical microscopy. Corrosion behavior was investigated using potentiodynamic tests and electrochemical impedance measurements (EIS .Results showed that vanadium and niobium addition precipitated stable carbides (VC, NbC to chromium carbides’ detriment and improved austenitic stainless steel corrosion resistance.

  8. Annealing dislocation loops in OKh16N15M3T steel implanted by helium

    International Nuclear Information System (INIS)

    Utkelbaev, B.D.; Reutov, V.F.; Zhdan, G.T.

    1993-01-01

    With the use of electron microscopy a study was made into the influence of preliminary thermomechanical treatment on the process of dislocation loop development in austenitic stainless steel type OKh16N15M3T with helium on annealing. Preliminary treatment was shown to prevent dislocation loop formation to a greater or lesser extent. Preliminary 'cold' working and thermal ageing of the material are the most effective ways to suppress radiation defect formation when annealing helium implanted steel

  9. Study of fatigue crack nucleation in 12% chromium stainless steel in sulphate and phosphate solutions

    International Nuclear Information System (INIS)

    Shalaby, H.M.; Begley, J.A.; Macdonald, D.D.

    1989-01-01

    The morphology of fatigue crack nucleation has been studied in 12%Cr stainless steel at a single stress level of 448 MN m -2 in deaerated H 2 SO 4 -Na 2 SO 4 -NaOH ([SO 4 2- ] = 0.01M and 1M) and in H 3 PO 4 -NaOH ([PO 4 3- ] = 0.01M and 1M) solutions at pH 2, 7 and 10 at 100 0 C. In sulphate solutions at pH 2, the specimen suffered overall surface attack without the initiation of microcracks. The surface attack intensified at the prior austenite grain boundaries, martensite platelet boundaries, and non-metallic inclusions. In contrast, cracks initiated transgranularly in sulphate solutions at pH 7 and 10 with the development of selective attack at crack sites at later stages in the fatigue life. This attack was ascribed to local acidification as a result of hydrolysis of corrosion products extruded from inside the cracks. Long cracks with crack branching and debonded zones were observed in all phosphate solutions, except in 0.01M phosphate solution at pH 7. In this latter environment, short intrusion-extrusion microcracks were observed. This difference in behaviour was attributed to changes in the characteristics of the passive film as influenced by the local environmental conditions, mechanical rupture by plastic deformation, and electrochemical differences at the metal surface. (author)

  10. LOCATING THE TRAILING EDGE OF THE CIRCUMBINARY RING IN THE KH 15D SYSTEM

    International Nuclear Information System (INIS)

    Capelo, Holly L.; Herbst, William; Leggett, S. K.; Hamilton, Catrina M.; Johnson, John A.

    2012-01-01

    Following two years of complete occultation of both stars in the binary T Tauri star KH 15D by its opaque circumbinary ring, KH 15D has abruptly brightened again during apastron phases, reaching I = 15 mag. Here, we show that the brightening is accompanied by a change in spectral class from K6/K7 (the spectral class of star A) to ∼K1, and a bluing of the system in V – I by about 0.3 mag. A radial velocity measurement confirms that, at apastron, we are now seeing direct light from star B, which is more luminous and of earlier spectral class than star A. Evidently, the trailing edge of the occulting screen has just become tangent to one anse of star B's projected orbit. This confirms a prediction of the precession models, supports the view that the tilted ring is self-gravitating, and ushers in a new era of the system's evolution that should be accompanied by the same kind of dramatic phenomena observed from 1995 to 2009. It also promotes KH 15D from a single-lined to a double-lined eclipsing binary, greatly enhancing its value for testing pre-main-sequence models. The results of our study strengthen the case for truncation of the outer ring at around 4 AU by a sub-stellar object such as an extremely young giant planet. The system is currently at an optimal configuration for detecting the putative planet and we urge expedient follow-up observations.

  11. Study of the first stages of oxidation of a ferritic-martensitic steel Fe-12Cr in CO2

    International Nuclear Information System (INIS)

    Bouhieda, S.

    2012-01-01

    In the framework of the development of Sodium Fast Reactors in France, supercritical carbon dioxide integrated in the Brayton cycle is proposed as new cycle energy conversion system to replace current steam generators. Ferritic-Martensitic steels with 9-12 wt% Cr are good candidates for heat exchanger application because they have good mechanical properties up to a temperature of 600 C, a high thermal conductivity, a low coefficient of thermal expansion and a lower cost than that of austenitic steels. However, it has been found that these steels present a high parabolic oxide growth rate and a strong carburization in the temperature and pressure conditions of the SC-CO 2 cycle (550 C, 250 bar). This study aims to investigate the influence of different parameters (impurities present in CO 2 , thermal ramp rate and surface state) on the oxidation mechanism of a Fe-12 Cr steel in CO 2 at 550 C. It has been shown that depending on these parameters, a thin protective oxide scale without any strong carburization can be obtained. A model is proposed to explain the experimental results. (author) [fr

  12. Evaluation of Corrosion Inhibition of Mild Steel in 1 M Hydrochloric Acid Solution by Mollugo cerviana

    Directory of Open Access Journals (Sweden)

    P. Arockiasamy

    2014-01-01

    Full Text Available The inhibiting effect of methanolic extract of Mollugo cerviana plant on the corrosion of mild steel in 1 M HCl solution has been investigated by different techniques like potentiodynamic polarization, electrochemical impedance spectroscopy, and weight loss methods for five different concentrations of plant extract ranging from 25 to 1000 mg/L. The results indicated that the corrosion inhibition efficiency increased on increasing plant extract concentration till 500 mg/L and decreased on further increasing concentration. The extract was a mixed type inhibitor with the optimum inhibition concentration of 500 mg/L in potentiodynamic polarization. The adsorption of the plant extract on the mild steel surface was found to obey Langmuir adsorption isotherm. Surface analysis was also carried out to find out the surface morphology of the mild steel in the presence and in the absence of the inhibitor to find out its efficiency. The obtained results showed that the Mollugo cerviana extract acts as a good inhibitor for the corrosion of mild steel in 1 M HCl solution.

  13. High temperature tensile properties and fracture characteristics of bimodal 12Cr-ODS steel

    International Nuclear Information System (INIS)

    Chauhan, Ankur; Litvinov, Dimitri; Aktaa, Jarir

    2016-01-01

    This article describes the tensile properties and fracture characteristics of a 12Cr oxide dispersion strengthened (ODS) ferritic steel with unique elongated bimodal grain size distribution. The tensile tests were carried out at four different temperatures, ranging from room temperature to 700 °C, at a nominal strain rate of 10"−"3 s"−"1. At room temperature the material exhibits a high tensile strength of 1294 MPa and high yield strength of 1200 MPa. At 700 °C, the material still exhibits relatively high tensile strength of 300 MPa. The total elongation-to-failure exceeds 18% over the whole temperature range and has a maximum value of 29% at 600 °C. This superior ductility is attributed to the material's bimodal grain size distribution. In comparison to other commercial, as well as experimental, ODS steels, the material shows an excellent compromise between strength and ductility. The fracture surface studies reveal a change in fracture behavior from a mixed mode fracture at room temperature to fully ductile fracture at 600 °C. At 700 °C, the fracture path changes from intragranular to intergranular fracture, which is associated with a reduced ductility. - Highlights: • The steel has a unique elongated bimodal grain size distribution. • The steel shows an excellent compromise between strength and ductility. • Superior ductility in comparison to other commercial and experimental ODS steels. • Fracture behavior changes from mixed mode fracture at room temperature to fully ductile fracture at 600 °C. • Fracture path changes from intragranular to intergranular fracture at 700 °C.

  14. Microstructure evolution and mechanical properties of X12CrMoWVNbN10-1-1 steel during quenching and tempering process

    Directory of Open Access Journals (Sweden)

    Xingang Tao

    2016-01-01

    Full Text Available The effect of heat treatments was investigated on the microstructure evolution and mechanical properties of X12CrMoWVNbN10-1-1 steel. The as-received steel was austenitized at 1080 °C for 16 h and cooled in furnace, following tempered in two steps, i.e. at 570 °C for 18 h and then at 690 °C for 24 h. The austenitized sample had a typical lath martensite structure with some retained austenite and no delta ferrite was observed after austenitization. After the first tempering at 570 °C, there was no retained austenite remained but it resulted in the forming of precipitates, such as Cr-rich M7C3, Cr-rich M23C6, Cr-rich M2N, Nb-rich MN, and the subgrain, as well as the reduction in dislocation density. However, microstructure observation after secondary tempering proved the further arrangement of dislocation, subgrain growth and the coarsening of precipitates. Hardness and impact tests were carried out for establishing a correlation between microstructure and mechanical properties. Finally, a careful fractographic analysis of impact samples had been done using SEM and EDS.

  15. 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

  16. [Effects of different amounts of phosphate fertilizers on copper, zinc transfer in red soil under the application of KH2PO4].

    Science.gov (United States)

    Guo, Liang; Li, Zhong-wu; Huang, Bin; Wang, Yan; Zhang, Yan

    2014-09-01

    In order to study the effects of different phosphate addition amounts on migration and transformation of heavy metals (Cu, Zn) in soil, an indoor leaching experiment using soil columns was carry out to study the leaching behavior of Cu and Zn. The KH2PO4 was chosen as the fertilizer application at the doses of 5 mg.kg-1, 15 mg.kg-1 and 25 mg.kg-1. The results showed that KH2PO4, could reduce the leachate pH, but different phosphate amounts had little effect on leachate pH, pH in leachate kept rising in the whole leaching process. With the application of KH2PO4, Cu migration was mainly in the surface layer while Zn migrated into deeper soil. Concentrations of Cu, Zn in deep soil leachate were low indicating that it was harmless to the shallow groundwater. After leaching, heavy metals mainly existed in the residual form in soil, the proportion of residual form of Cu was around 60% and the proportion of residual form of Zn was around 40%. High concentration of KH2PO4 helps the transformation of Zn from residual organic combination state to exchange state.

  17. Comparative assessment of microstructure and texture in the Fe-30.5Mn-8.0Al-1.2C and Fe-30.5Mn-2.1Al-1.2C steels under cold rolling

    Directory of Open Access Journals (Sweden)

    Fabrício Mendes Souza

    Full Text Available Abstract Investigation of microstructure and texture has been done for cold rolled Fe-30.5Mn-8.0Al-1.2C (8Al and Fe-30.5Mn-2.1Al-1.2C (2Al (wt.% steels. They were rolled to a strain of ~0.70. Refinement of a crystallographic slip band substructure in low to medium rolling strain and nucleation of twins on the mature slip bands at a higher strain were suggested as deformation mechanisms in the 8Al steel. Mainly shear banding contributed to the formation of a Copper texture in such steel. Brass-texture development in the 2Al steel is mainly due to deformation twinning and shear banding formation. Detailed images of KAM maps showed that the stored deformation energy was mainly localized in the twinned areas and shear bands, which generated the inhomogeneous deformation microstructures in both steels at a higher strain. Goss and Brass texture intensity decreases and Cu-texture intensity increases as the Al wt.% increases in different cold rolled High-Mn (Mn ~30 wt.% steels.

  18. Changes In Properties and Microstructure of High-Chromium 9-12%Cr Steels Due to Long-Term Exposure at Elevated Temperature

    Directory of Open Access Journals (Sweden)

    Zieliński A.

    2016-06-01

    Full Text Available This paper presents the characteristics of the performance of P91 (X10CrMoVNb9-1, P92 (X10CrWMoVNb9-2 and VM12 (X12CrCoWVNb12-2-2 steels used for condition assessment of the pressure components of boilers with supercritical steam parameters. Studies on the mechanical properties, microstructure tests using scanning and transmission electron microscopy, and X-ray analysis of the phase composition of precipitates were performed for selected steels in the as-received condition and after long-term annealing. These steel characteristics are used for the evaluation of the microstructural changes and mechanical properties of the material of components after long-term service. The result of this study is the database of material characteristics representing the mechanical properties related to the microstructure analysis and it can be used for diagnosis of the components of pressure parts of power boilers.

  19. Influence of heat treatment on microstructure and properties of GX12CrMoVNbN9-1 cast steel

    Directory of Open Access Journals (Sweden)

    G. Golański

    2010-07-01

    Full Text Available The paper presents results of research on the influence of multistage heat treatment on microstructure and properties of high-chromiummartensitic GX12CrMoVNbN9 – 1 (GP91 steel. The material under investigation were samples taken out from a test coupon. Heattreatment of GP91 cast steel was performed at the parameters of temperature and time typical of treatment for multi-ton steel casts. The research has proved that in the as-received condition (as-cast state GP91 cast steel was characterized by a coarse grain, martensitic microstructure which provided the required standard mechanical properties. The heat treatment of GP91 cast steel contributed to obtainment of a fine grain microstructure of high tempered martensite with numerous precipitations of carbides of diverse size. The GP91 cast steel structure received through heat treatment made it possible to obtain high plastic properties, particularly impact strength, maintaining strength properties on the level of the required minimum.

  20. Bulgarian ethnos according to A.Kh. Khalikov’ works: scientific concept and its theoretical bases

    Directory of Open Access Journals (Sweden)

    Izmaylov Iskander L.

    2017-02-01

    Full Text Available The article is devoted to the problems of Bulgar and Tatar ethnogenesis studied in the works of the prominent Kazan archaeologist A.Kh. Khalikov. His concept was based on the fact that a number of ethnic groups (Turkic, Finno-Ugric, and East Slavic participated in the formation of these peoples and that the key role in these processes was played by their mutual cultural influence. The concept of ethnogenesis and ethnic history of the Tatar people offered by A.Kh. Khalikov was a serious theoretical breakthrough against the background of both ideology-biased historical schemes of the Soviet era and the various nationalist ideas, differing from them by a comprehensive, integral scientific analysis of predominantly archaeological data. At present, however, when theoretical and factual bases of historical and ethnological research have considerably expanded, a number of conflicting issues have arisen in the framework of this concept, which, therefore, require new approaches to their solution.

  1. Comparative study of AISI M3:2 high speed steel produced through different techniques of manufacturing; Estudo comparativo de acos rapidos AISI M3:2 produzidos por diferentes processos de fabricacao

    Energy Technology Data Exchange (ETDEWEB)

    Araujo Filho, Oscar Olimpio de

    2006-07-01

    In this work AISI M3:2 high speed steels obtained through different techniques of manufacturing, submitted to the same heat treatment procedure were evaluated by measuring their mechanical properties of transverse rupture strength and hardness. Sinter 23 obtained by hot isostatic pressing (HIP), VWM3C obtained by the conventional route and a M3:2 high speed steel obtained by cold compaction of water atomized powders and vacuum sintered with and without the addition of a small quantity of carbon were evaluated after the same heat treatment procedure. The vacuum sintered M3:2 high speed steel can be an alternative to the more expensive high speed steel produced by hot isostatic pressing and with similar properties presented by the conventional one. The characterization of the vacuum sintered M3:2 high speed steel was performed by measuring the densities of the green compacts and after the sintering cycle. The sintering produced an acceptable microstructure and densities near to the theoretical. The transverse rupture strength was evaluated by means of three point bending tests and the hardness by means of Rockwell C and Vickers tests. The technique of scanning electronic microscopy (SEM) was used to evaluate the microstructure and to establish a relation with the property of transverse rupture strength. The structure was determined by means of X-ray diffraction (XRD) patterns and the retained austenite was detected to all the conditions of heat treatment. The main contribution of this work is to establish a relation between the microstructure and the mechanical property of transverse rupture strength and to evaluate the AISI M3:2 vacuum sintered high speed steel as an alternative to the similar commercial high speed steels. (author)

  2. Hot ductility of structural steels melted with the use of direct reduction charge

    International Nuclear Information System (INIS)

    Marchenko, V.N.; Bulat, S.I.; Litvinenko, D.A.

    1982-01-01

    A possibility of the use of direct reduction charge during the open arc melting of the 40Kh2N2MA steel with the subsequent electroslag remelting was investigated. It is shown that the use of such charge free from non-ferrous metal admixtures permits to increase an alloy hot ductility in the hot-brittleness range from 900 up to 1500 deg C. An increase of the deformation rate from 0.1 up to 1 s - 1 increases 1.5-3 times a level of minimum ductility within this temperature range. It is established that antimony and bismuth impurities considerably decrease hot ductility

  3. Irradiation performance of 9--12 Cr ferritic/martensitic stainless steels and their potential for in-core application in LWRs

    International Nuclear Information System (INIS)

    Jones, R.H.; Gelles, D.S.

    1993-08-01

    Ferritic-martensitic stainless steels exhibit radiation stability and stress corrosion resistance that make them attractive replacement materials for austenitic stainless steels for in-core applications. Recent radiation studies have demonstrated that 9% Cr ferritic/martensitic stainless steel had less than a 30C shift in ductile-to-brittle transition temperature (DBTT) following irradiation at 365C to a dose of 14 dpa. These steels also exhibit very low swelling rates, a result of the microstructural stability of these alloys during radiation. The 9 to 12% Cr alloys to also exhibit excellent corrosion and stress corrosion resistance in out-of-core applications. Demonstration of the applicability of ferritic/martensitic stainless steels for in-core LWR application will require verification of the irradiation assisted stress corrosion cracking behavior, measurement of DBTT following irradiation at 288C, and corrosion rates measurements for in-core water chemistry

  4. Organizational and technological compatibility of the technological processes of second and third line maintenance of KhTZ-3522 tractors

    Directory of Open Access Journals (Sweden)

    Kyzminskyj Roman

    2018-01-01

    Full Text Available The work is devoted to systematic substantiation of productivity, production structure and specialization of service stations of KhTZ-3522 tractors. Based on the technical and economic comparative analysis of the results of the technological processes modeling of the second and third line maintenance of KhTZ-3522 tractors, the parametrical series of production structures of service stations both mono- and polytechnological specialization, which can work effectively in a wide range of the general annual program of orders, and in the conditions of seasonal fluctuations of orders for the maintenance of these tractors, are found. The results of calculations of the indicators system for organizational and technological compatibility of technological processes of the second and third line maintenance of KhTZ-3522 tractors in the joint technological flow are presented. The dependencies of these indicators on the total annual program of orders for service stations of different productivity are analyzed. According to the results of the analysis, the polytechnological specialization of such service stations is substantiated.

  5. Hasan Basri Çantay’ın “On Kere Kırk Hadis” Adlı Eserinde Ahkâm Hadislerine Getirdiği Fıkhî Yorumlar

    Directory of Open Access Journals (Sweden)

    Mehmet Özkan

    2015-06-01

    Full Text Available Milli mücadele yıllarının öne çıkan isimlerinden biri olan Hasan Basri Çantay yazarlık, gazetecilik, öğretmenlik ve milletvekilliği gibi birçok alanda faaliyet göstermiş, çeşitli konularda yazılar yazmış, eserler kaleme almıştır. İslami ilimler alanında da kendini yetiştiren Çantay’ın bu alandaki en önemli eseri “Kur’an-ı Hakîm ve Meal-i Kerîm” adlı Kur’an mealidir. İkinci önemli eseri, “On Kere Kırk Hadis” adlı kitabıdır. 1955-1962 yılları arasında üç cilt halinde basılan bu kitap iman, ibâdet, temizlik, ahlak, muâmelat, evlenme, boşanma, suç ve cezalar, şûra, askerlik ve cihat, savaş hukuku,  helal,  haram gibi birçok konuyla ilgili bin iki yüz hadisten oluşmaktadır. Bunların yaklaşık dört yüz yirmisi ahkâm hadisidir. Çantay, hadisleri tercüme etmekle kalmamış yeri geldikçe izahlarda da bulunmuştur. Bu çalışmada Çantay’ın yaklaşık yüz otuz ahkâm hadisine yaptığı izah ve fıkhî değerlendirmelerden örneklere yer verilecektir.

  6. Steam oxidation of 9-12%Cr steels. Critical evaluation and implications for practical application

    Energy Technology Data Exchange (ETDEWEB)

    Zurek, J.; Quadakkers, W.J. [Forschungszentrum Juelich GmbH (DE). Inst. fuer Energieforschung (IEF); Bruycker, E. de; Huysmans, S. [Laborelec, Linkebeek (Belgium)

    2010-07-01

    In new and future generation Power Plants, creep resistant steels selected for high-temperature components are subjected to a large variety of service environments. In many of these applications, water vapor has been found to substantially alter the technologically relevant properties mainly growth rate and adherence, of the surface oxides. Various data sets exist in the literature for steam oxidation for this type of steels, however these data show a substantial deviation. These differences can be related to e.g. ''batch to batch'' variation, oxidation conditions, surface treatment, difference between laboratory/power plants data, etc. Therefore these literature data need careful and critical verification when being used to estimate the long term materials behaviour in real power generation plants. The paper discusses the existing steam oxidation data for a number of selected steels, i.e. P91, P92 and VM12, thereby putting main emphasis on discussing the parameters which are responsible for observed variations in oxidation rates for the various types of materials. (orig.)

  7. Fabrication and characterization of reference 9Cr and 12Cr-ODS low activation ferritic/martensitic steels

    Energy Technology Data Exchange (ETDEWEB)

    Muroga, T., E-mail: muroga@nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Nagasaka, T. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Li, Y.; Abe, H. [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Ukai, S. [Graduate School of Engineering, Hokkaido University, N13, W8, Kita-ku, Sapporo 060-8628 (Japan); Kimura, A. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Okuda, T. [Kobelco Research Institute, 1-5-5 Takatsukadai, Nishi-ku, Kobe, Hyogo 651-2271 (Japan)

    2014-10-15

    For the purpose of arranging reference alloys available for various characterization efforts by Japanese fusion research groups, fabrication of reference 9Cr and 12Cr-ODS steels have been carried out with similar manufacturing processes followed by various characterizations. The fabrication proceeded with powder mixing, MA, encapsulation into mild steel cases, hot extrusion and hot forging, followed by final heat treatments. Each alloy was extruded into three bars. The characterization included chemical composition analysis, SEM and TEM microstructural observations, hardness tests, tensile tests at RT and 973 K, and relatively short-term thermal creep tests at 973 K. Room temperature hardness for 9Cr-ODS was larger than 12Cr-ODS, the former showing large increase when annealing temperature exceeded 1200 K and the latter showing no significant change with annealing temperature. Tensile strength of 9Cr-ODS was significantly larger than that of 12Cr-ODS at RT but comparable at 973 K. 9Cr-ODS showed longer and shorter creep rupture time than 12Cr-ODS at high and low stress levels, respectively. The mechanism of the difference in creep properties of the two alloys was discussed.

  8. PENDIDIKAN KARAKTER MENURUT K.H. HASYIM ASY’ARI DALAM KITAB ADÂB AL-‘ÂLIM WA AL-MUTA‘ALLIM

    OpenAIRE

    Sholikah Sholikah

    2015-01-01

    The article deals with K.H. Hasyim Asy’ari’s thought of character education. The result of the study indicates that according to K.H. Hasyim Asy’ari the characters of teachers and students in his work Adab al-‘Âlim wa al-Muta’allim can be classified into three parts, are mentality or character, which should be possessed by teachers and learners: attempts to be done in order to become characterized teachers and learners, and: teaching strategies employed by educators and learning strategies us...

  9. Optimum tungsten content in high strength 9 to 12% chromium containing creep resistant steels

    International Nuclear Information System (INIS)

    Hasegawa, Y.; Muraki, T.; Mimura, H.

    2000-01-01

    Tungsten containing ferritic creep resistant steels are the candidate materials for ultra-super-critical fossil power plant because of their high creep rupture strength. But the strengthening mechanisms by tungsten addition have not yet been completely studied. In this report, creep rupture time and creep strain rate measurement decided the optimum tungsten content in 9 to 12% chromium ferritic steels. The precipitation behavior of Laves phase and the precise discussion of creep strain rate analyses explain the contribution of Laves phase at the lath boundary and the contribution of tungsten in solid solution. P92 contains the optimum amount of tungsten and chromium, 1.8 mass% and 9 mass% respectively judging from the creep rupture strength point of view. (orig.)

  10. Continuous cooling transformation behaviors of CLAM steel

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qing-sheng, E-mail: qingsheng.wu@fds.org.cn; Zheng, Shu-hui; Huang, Qun-ying; Liu, Shao-jun; Han, Yang-yang

    2013-11-15

    The continuous cooling transformation (CCT) behaviors of CLAM (China Low Activation Martensitic) steel were studied, the CCT diagram was constructed, and the influence of cooling rates on the microstructures was also investigated. The microstructures were investigated using optical microscopy (OM) and microhardness tests were also carried out. The results showed that CLAM steel possessed high hardenability and there were ferrite and martensite transformation regions only. The maximum cooling rate to form ferrite microstructure was found to be 10–12 K/min. In order to obtain fully ferrite microstructure, the cooling rate should be lower than 1 K/min. The CCT diagram also gave relevant parameters such as the transformation temperatures, i.e., A{sub c1}, A{sub c3}, M{sub s} and M{sub f} were 1124 K, 1193 K, 705 K and 593 K, respectively. The diagram made it possible to predict the microstructures and properties of CLAM steel with different cooling rates.

  11. Continuous cooling transformation behaviors of CLAM steel

    International Nuclear Information System (INIS)

    Wu, Qing-sheng; Zheng, Shu-hui; Huang, Qun-ying; Liu, Shao-jun; Han, Yang-yang

    2013-01-01

    The continuous cooling transformation (CCT) behaviors of CLAM (China Low Activation Martensitic) steel were studied, the CCT diagram was constructed, and the influence of cooling rates on the microstructures was also investigated. The microstructures were investigated using optical microscopy (OM) and microhardness tests were also carried out. The results showed that CLAM steel possessed high hardenability and there were ferrite and martensite transformation regions only. The maximum cooling rate to form ferrite microstructure was found to be 10–12 K/min. In order to obtain fully ferrite microstructure, the cooling rate should be lower than 1 K/min. The CCT diagram also gave relevant parameters such as the transformation temperatures, i.e., A c1 , A c3 , M s and M f were 1124 K, 1193 K, 705 K and 593 K, respectively. The diagram made it possible to predict the microstructures and properties of CLAM steel with different cooling rates

  12. Density functional calculations on 13-atom Pd12M (M = Sc—Ni) bimetallic clusters

    International Nuclear Information System (INIS)

    Tang Chun-Mei; Chen Sheng-Wei; Zhu Wei-Hua; Tao Cheng-Jun; Zhang Ai-Mei; Gong Jiang-Feng; Zou Hua; Liu Ming-Yi; Zhu Feng

    2012-01-01

    The geometric structures, electronic and magnetic properties of the 3d transition metal doped clusters Pd 12 M (M = Sc—Ni) are studied using the semi-core pseudopots density functional theory. The groundstate geometric structure of the Pd 12 M cluster is probably of pseudoicosahedron. The I h -Pd 12 M cluster has the most thermodynamic stability in five different symmetric isomers. The energy gap shows that Pd 12 M cluster is partly metallic. Both the absolutely predominant metal bond and very weak covalent bond might exist in the Pd 12 M cluster. The magnetic moment of Pd 12 M varies from 0 to 5 μ B , implying that it has a potential application in new nanomaterials with tunable magnetic properties

  13. Statistical analysis of fatigue crack growth behavior for grade B cast steel

    International Nuclear Information System (INIS)

    Li, W.; Sakai, T.; Li, Q.; Wang, P.

    2011-01-01

    Tests for fatigue crack growth rate (FCGR) and crack-tip opening displacement (CTOD) were performed to clarify the fatigue crack growth behavior of a railway grade B cast steel. The threshold values of this steel with specific survival probabilities are evaluated, in which the mean value is 8.3516 MPa m 1/2 , very similar to the experimental value, about 8.7279 MPa m 1/2 . Under the conditions of plane strain and small-scale yielding, the values of fracture toughness for this steel with specific survival probabilities are converted from the corresponding critical CTOD values, in which the mean value is about 138.4256 MPa m 1/2 . In consideration of the inherent variability of crack growth rates, six statistical models are proposed to represent the probabilistic FCGR curves of this steel in entire crack propagation region from the viewpoints of statistical evaluation on the number of cycles at a given crack size and the crack growth rate at a given stress intensity factor range, stochastic characteristic of crack growth as well as statistical analysis of coefficient and exponent in FCGR power law equation. Based on the model adequacy checking, result shows that all models are basically in good agreement with test data. Although the probabilistic damage-tolerant design based on some models may involve a certain amount of risk in stable crack propagation region, they just accord with the fact that the dispersion degree of test data in this region is relatively smaller.

  14. Isolation of HL-60 cancer cells from the human serum sample using MnO2-PEI/Ni/Au/aptamer as a novel nanomotor and electrochemical determination of thereof by aptamer/gold nanoparticles-poly(3,4-ethylene dioxythiophene) modified GC electrode.

    Science.gov (United States)

    Amouzadeh Tabrizi, Mahmoud; Shamsipur, Mojtaba; Saber, Reza; Sarkar, Saeed

    2018-07-01

    Herein, aptamer-modified self-propelled nanomotors were used for transportation of human promyelocytic leukemia cells (HL-60) from a human serum sample. For this purpose, the fabricated manganese oxide nanosheets-polyethyleneimine decorated with nickel/gold nanoparticles (MnO 2 -PEI/Ni/Au) as nanomotors were added to a vial containing thiolated aptamer KH1C12 solution as a capture aptamer to attach to the gold nanoparticles on the surface of nanomotors covalently. The aptamer-modified self-propelled nanomotors (aptamer KH1C12 /nanomotors) were then separated by placing the vial in a magnetic stand. The aptamer-modified self-propelled nanomotors were rinsed three times with water to remove the non-attached aptamers. Then, the resulting aptamer KH1C12 /nanomotors were applied for the on-the-fly" transporting of HL-60 cancer cell from a human serum sample. To release of the captured HL-60 cancer cells, the complementary nucleotide sequences of KH1C12 aptamer solution (releasing aptamer) that has a with capture aptamer was added to phosphate buffer solution (1 M, pH 7.4) containing HL-60/aptamer KH1C12 /nanomotors. Because of the high affinity of capture aptamer to complementary nucleotide sequences of aptamer KH1C12 , the HL-60 cancer cells released on the surface of aptamer KH1C12 /nanomotors into the solution. The second goal of the present work was determining the concentration of HL-60 cancer cell in the human serum samples. The electrochemical impedance spectroscopy technique (EIS) was used for the determination of HL-60 cancer cell. The concentration of separated cancer cell was determined by aptamer/gold nanoparticles-poly(3,4-ethylene dioxythiophene) modified GC electrode (GC/PEDOT-Au nano /aptamer KH1C12 ). The proposed aptasensor exhibited a good response to the concentration of HL-60 cancer cells in the range of 2.5 × 10 1 to 5 × 10 5 cells mL -1 with a low limit of detection of 250 cells mL -1 . Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Hot rolling of chromium - nickel - manganese stainless steel containing nitrogen and boron

    International Nuclear Information System (INIS)

    Khorosh, V.A.; Bulat, S.I.; Mukhina, M.A.; Sorokina, N.A.; Yushchenko, K.A.; Tsentral'nyj Nauchno-Issledovatel'skij Inst. Chernoj Metallurgii, Moscow; AN Ukrainskoj SSR, Kiev. Inst. Ehlektrosvarki)

    1976-01-01

    The strength of stainless steel of the 03Kh2ON16AG6 type increases perceptibly with an increase in the nitrogen content from 0.11 to 0.37%. At the same time, however, its ductility in the region of hot deformation temperatures (red brittleness range of 800 to 1,000 deg C) decreases. Microalloying with boron (0.002 to 0.005% by calculation) permits enhancing the hot ductility to an acceptable level without adversely affecting the working properties. The mechaniusm of boron effect is analyzed. The temperature at which ingots are heated prior to rolling to achieve the desired effect must be sufficiently low. Optimum condition for two stage heating of 6.2-ton ingots are recommeded

  16. Effect of microplastic strain on hydrogen behaviour in steel and resistance to hydrogen embrittlement

    Energy Technology Data Exchange (ETDEWEB)

    Gribanova, L.I.; Sarrak, V.I.; Filippov, G.A.; Shlyafirner, A.M. (Tsentral' nyj Nauchno-Issledovatel' skij Inst. Chernoj Metallurgii, Moscow (USSR))

    1981-01-01

    A connection between the tendency to delayed fracture and resistance to microplastic deformation is studied in the presence of hydrogen on smooth samples of the 40Kh steel. Tests for delayed fracture have been carried out at the ''Instron'' machine. Two critical levels of strains during delayed fracture in the hydridation process are found out (sigmasub(cr1)=0.3sigmasub(0.2) and sigmasub(cr2)=0.5sigmasub(0.2)). At stresses below the sigmasub(cr1) hydrogen does not influence on the resistance to microplastic deformation of steel and does not cause delayed fracture. Propagation of cracks arising from defects occurring as a result of mutual effect of hydrogen and elastic stresses runs in the stress range from sigmasub(cr1) up to sigmasub(cr2). At stresses higher than sigmasub(cr2) the crack propagates from defects existing in the moment of hydridation process beginning.

  17. Refining the microstructure of an AISI M2 tool steel by high-energy milling

    International Nuclear Information System (INIS)

    Postiglioni, R.V.; Alamino, A.E; Vurobi Junior, S.

    2009-01-01

    Samples of AISI M2 steel were produced by high-energy milling from chips of machining in Spex high energy mill, compaction and sintering of the powder obtained. The powder was analyzed by X-ray diffraction, and then compressed in discs of 8mm in diameter. The specimens have sintering at 1200 deg C for 1 hour under vacuum atmosphere, followed by annealing, quenching and tempering for 1 hour at 315 deg C and 540°C. Along with each disc, a sample of as-received steel was subjected to the same heat treatments to compare the final microstructure. After standard metallographic preparation, samples were etched with Beraha's reagent, characterized by optical microscopy, quantitative metallography, scanning electron microscopy with micro analysis and mapping by EDS, besides Vickers hardness. The steel produced by high-energy milling presented more refined carbide and better distribution in the microstructure. There was also reduction in the size of prior austenitic grains. (author)

  18. Production of oxytetracycline by Streptomyces rimosus 12,907 as an animal feed supplement

    Energy Technology Data Exchange (ETDEWEB)

    Baghlaf, A O; Abou-Zeid, A; El-Dewany, A I; Eissa, I; Fouad, M; Yassein, M

    1980-01-01

    Production of oxytetracycline by S. rimosus 12,907 as an animal feed supplement was achieved with a fermentation medium containing the following ingredients: blackstrap molasses 30, fodder yeast 20, rice bran 10, KH2PO4 0.2%, and water to 1000 mL. The dry mash, containing oxytetracycline, was 50 g/L of fermentation medium. The amount of oxytetracycline, present in the dry mash, was approximately 4.0%. The dry mash, also contained the following amino acids: L-arginine, L-histidine, L-lysine, L-isoleucine, L-leucine, L-phenylalanine, DL-methionine, and L-tryptophan.

  19. Constructing kinetics fatigue diagrams using testing results obtained on a machine with rigid loading for specimens of various thickness

    International Nuclear Information System (INIS)

    Simin'kovich, V.N.; Gladkij, Ya.N.; Deev, N.A.

    1981-01-01

    Bending tests of 40KhS steel specimens, tempered at 200 and 500 deg C, are conducted to investigate the possible effects of specimen thickness on fatigue crack growth. Kinetic fatigue diagrams are constructed using the investigation results. An increase in crack growth with thickness is observed only in high-tempered specimens. Changes in specimen thickness do not affect crack growth in 40KhS low-tempered steel [ru

  20. Pendidikan Karakter Menurut K.H. Hasyim Asy'ari Dalam Kitab Adâb Al-‘Âlim Wa Al-Muta‘Allim

    OpenAIRE

    Sholikah, Sholikah

    2015-01-01

    The article deals with K.H. Hasyim Asy'ari's thought of character education. The result of the study indicates that according to K.H. Hasyim Asy'ari the characters of teachers and students in his work Adab al-‘Âlim wa al-Muta'allim can be classified into three parts, are mentality or character, which should be possessed by teachers and learners: attempts to be done in order to become characterized teachers and learners, and: teaching strategies employed by educators and learning strategies us...

  1. The inhibitory effect of different concentrations of KH902 eye drops on corneal neovascularization induced by alkali burn

    Directory of Open Access Journals (Sweden)

    Yan Wu

    2017-01-01

    Full Text Available Purpose: The aim of this study was to evaluate the inhibitory effect of different concentrations of KH902 eye drops on rabbit corneal neovascularization (CNV induced by alkali burn. Methods: Forty-eight adult rabbits were randomized into four groups after alkali burning: Group A (2.5 mg/ml, Group B (5 mg/ml, and Group C (10 mg/ml by different concentrations of KH902 eye drops and Group D by saline solution as control with three times a day for 2 weeks. At days 7, 14, and 28, the anterior segment photographs, confocal microscopy, and histopathology were performed to evaluate corneal opacity, neovascularization, inflammatory cell density, vessel size, and edema. Immunohistochemistry was applied to analyze the vascular endothelial growth factor (VEGF level. Results: (1 The CNV in the medicine-treated groups showed a reduction without obvious corneal side effects histologically. (2 Compared to the control group, the three medicine-treated groups showed a reduction in the VEGF levels and CNV areas on days 7, 14, and 28 and in the inflammatory cell density on days 14 and 28 (P 0.05. Conclusion: KH902 eye drops in lower concentration showed an obvious reduction of the CNV growing for rabbit corneal alkali burn without side effects.

  2. On the hypothesis of agressive environment effect evaluation on the cyclic cracking resistance in metals and alloys

    International Nuclear Information System (INIS)

    Romaniv, O.N.; Gladkij, Ya.N.; Nikiforchin, G.N.

    1978-01-01

    Experimental data on studying static and cyclic cracking resistances of steels in water and inert gaseous media are given. Presented are experimental values of threshold coefficients of stress intensities for a series of the systems: metal (the 4340 steel of the 45KhN2MFA type, 12Ni-5Cr-3Mo steel, 9Ni-4Co-0.25C steel and others)-medium. On the base of the above data analysis and representations on the mechanism of crack growth under conditions of permanent and variable load effects the conclusion is drawn on the groundlessness of the hypothesis of contribution superposition resulted from pure fatigue and corrosion-static factors when estimating cracking resistance of metals and alloys

  3. Fatigue-creep of martensitic steels containing 9-12% Cr: behaviour and damage; Fatigue-fluage des aciers martensitiques a 9-12% Cr: comportement et endommagement

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, B

    2007-09-15

    It is in the framework of the research programs on nuclear reactors (generation IV) that the martensitic steels containing 9-12% Cr are studied by the CEA. Most of the structures for which they are considered will be solicited in fatigue-creep at high temperature (550 C). The aim of this work is to understand and model the cyclic behaviour and the damage of these materials. The proposed modelling are based on detailed observations studies (SEM, TEM, EBSD...). The cyclic softening is attributed to the growth of the microstructure. A micro-mechanical model based on the physical parameters is proposed and leads to encouraging results. The damage results of interactions between fatigue, creep and oxidation. Two main types of damage are revealed. A model of anticipation of service time is proposed and gives very satisfying results. The possible extrapolations are discussed. (O.M.)

  4. Effects of Static Recrystallization and Precipitation on Mechanical Properties of 00Cr12 Ferritic Stainless Steel

    Science.gov (United States)

    Shao, Yi; Liu, Chenxi; Yue, Tengxiao; Liu, Yongchang; Yan, Zesheng; Li, Huijun

    2018-05-01

    The 00Cr12 ferritic stainless steel samples were isothermally held at different temperatures in the range of 700 °C to 1000 °C to investigate the effect of static recrystallization and precipitation on mechanical properties, such as microhardness, tensile strength, and yield strength. The results show that the formation of the fine recrystallized grain, as well as precipitation, coarsening, and dissolution of the second-phase particles, influences the mechanical properties remarkably. The fine recrystallized grain can provide a positive grain boundary-strengthening effect in the sample under a relatively high holding temperature. Coarsening and dissolution of M23C6 result in partial depletion of precipitate hardening. In contrast, the size and number density of MX particles are almost constant, regardless of the holding temperature; therefore, it can provide a better precipitation-hardening effect.

  5. Preliminary evaluation of a constructed wetland for treating extremely alkaline (pH 12) steel slag drainage.

    Science.gov (United States)

    Mayes, W M; Aumônier, J; Jarvis, A P

    2009-01-01

    High pH (> 12) leachates are an environmental problem associated with drainage from lime (CaO)-rich industrial residues such as steel slags, lime spoil and coal combustion residues. Recent research has highlighted the potential for natural ('volunteer') wetlands to buffer extremely alkaline influent waters. This appears ascribable to high CO(2) partial pressures in the wetland waters from microbial respiration, which accelerates precipitation of calcium carbonate (CaCO(3)), and the high specific surface area for mineral precipitation offered by macrophytes. The research presented here builds on this and provides preliminary evaluation of a constructed wetland built in March 2008 to buffer drainage from steel slag heaps in north-east England. The drainage water from the slag mounds is characterised by a mean pH of 11.9, high concentrations of Ca (up to 700 mg/L), total alkalinity (up to 800 mg/L as CaCO(3)) and are slightly brackish (Na = 300 mg/L; Cl = 400 mg/L) reflecting native groundwaters at this coastal setting. Documented calcite precipitation rates (mean of 5 g CaCO(3)/m(2)/day) from nearby volunteer sites receiving steel slag drainage were used to scale the constructed wetland planted with Phragmites australis; a species found to spontaneously grow in the vicinity of the discharge. Improved performance of the wetland during summer months may at least in part be due to biological activity which enhances rates of calcite precipitation and thus lowering of pH. Secondary Ca-rich precipitates also serve as a sink for some trace elements present at low concentrations in the slag leachate such as Ni and V. The implications for scaling and applying constructed wetlands for highly alkaline drainage are discussed.

  6. High temperature oxidation of 9% and 12% Cr steel: effect of water vapour; Oxidation haute temperature d'un acier 9% et 12% de teneur Cr. Effet de la vapeur d'eau

    Energy Technology Data Exchange (ETDEWEB)

    Evin, H.; Heritier, D.; Chevalier, S. [Universite de Bourgogne, Institut Carnot de Bourgogne UMR 5209 CNRS, 21 - Dijon (France); Fojer, C. [OCAS N.V. ArcelorMittal Research Industry Gent, Zelzate (Belgium)

    2008-07-01

    Isothermal tests were performed on commercial 9%Cr and 12%Cr steels between 600 and 750 deg C in air under atmospheric pressure. The same steels were also tested in oxidizing atmosphere enriched with 12% H{sub 2}O at 700 deg C for 24 hours. Kinetics data were registered and the corrosion products were analyzed using different characterization tools such as scanning electron microscope, x-ray diffraction and secondary ions mass spectrometry. 9%Cr steels showed very limited high temperature corrosion behavior in air, because a breakaway appeared after less than 80 hours at 750 deg C. Spinel oxides composed of iron, chromium and manganese (Mn{sub 1.5}Cr{sub 1.5}O{sub 4} and MnFe{sub 2}O{sub 4}) were identified over the surfaces of both steel grades after oxidation. (Cr,Fe){sub 2}O{sub 3} was also identified especially at 700 deg C and 750 deg C, whereas Fe{sub 2}O{sub 3} mainly grew at 600 and 650 deg C. Differences in oxide morphology and composition were noticed between the samples oxidized under air and air + 12 % water vapor. (authors)

  7. Study of regularities in propagation of thermal fatigue cracks

    International Nuclear Information System (INIS)

    Tachkova, N.G.; Sobolev, N.D.; Egorov, V.I.; Rostovtsev, Yu.V.; Ivanov, Yu.S.; Sirotin, V.L.

    1978-01-01

    Regularities in the propagation of thermal fatigue cracks in the Cr-Ni steels of the austenite class depending upon deformation conditions in the crack zone, have been considered. Thin-walled tube samples of the Kh16N40, Kh18N20 and Kh16N15 steels have been tested in the 10O reversible 400 deg C and 100 reversible 500 deg C regimes. The samples have possessed a slot-shaped stress concentrator. Stress intensity pseudocoefficient has been calculated for the correlation of experimental data. The formula for determining crack propagation rate has been obtained. The experiments permit to conclude that propagation rate of thermal fatigue cracks in the above steels depends upon the scope of plastic deformation during a cycle and stress intensity pseudocoefficient, and is determined by plastic deformation resistance during thermal cyclic loading

  8. Inhibition of salt precipitation, corrosion and corrosion fatigue of steel in neutral environments

    International Nuclear Information System (INIS)

    Mikhajlovskij, V.Ya.; Slobodyan, Z.V.; Soprunyuk, N.G.; Ivanov, A.M.

    1983-01-01

    Processes of salt precipitation, corrosion under dynamic and static conditions, are studied as well as corrosion fatigue of 20 and 40Kh steels in neutral aqueous media without and with the addition of compounds of several classes. The solution of calcium bicarbonate with the initial concentration [Ca(HCO 3 ) 2 ]=1.3 g/l and 3% NaCl solution in distilled water are used for investigation. The effectiveness index of salt precipitation inhibitor is determined by the change in the rate of calcium bicarbonate transformation into carbonate. The combination of results obtained permits to make the conclusion that tripolyphosphate and pyrophosphoric acid are rather perspective inhibitors of complex effect with low protective concentrations

  9. Estimation of flow stress of radiation induced F/M steels using molecular dynamics and discrete dislocation dynamics approach

    International Nuclear Information System (INIS)

    More, Ameya; Dutta, B.K.; Durgaprasad, P.V.; Arya, A.K.

    2012-01-01

    Fe-Cr based Ferritic/Martensitic (F/M) steels are the candidate structural materials for future fusion reactors. In this work, a multi-scale approach comprising atomistic Molecular Dynamics (MD) simulations and Discrete Dislocation Dynamics (DDD) simulations are used to model the effect of irradiation dose on the flow stress of F/M steels. At the atomic scale, molecular dynamics simulations are used to study the dislocation interaction with irradiation induced defects, i.e. voids and He bubbles. Whereas, the DDD simulations are used to estimate the change in flow stress of the material as a result of irradiation hardening. (author)

  10. In-situ ultrasonic characterisation of M250 grade maraging steel

    International Nuclear Information System (INIS)

    Sakthipandi, K.; Rajesh Kanna, R.; Lenin, N.; Ahilandeswari, E.

    2016-01-01

    The excellent mechanical properties such as ultrahigh strength combined with good fracture toughness, hardness, ductility and corrosion resistance of maraging steels makes these steels the most preferred materials for nuclear power plants. The high strength and high fracture toughness of these maraging steels are characterised by intermetallic precipitation in iron-nickel martensite. The temperature dependent in-situ microstructural characterisation of maraging steel over wide range of temperatures is used to explore the microstructural changes in maraging steels during aging. An indigenous experimental set-up was used for in-situ measurements of ultrasonic longitudinal velocity (UL) over a wide range of temperatures from 300 to 1200 K at a heating rate of 1 K min -1 . The measured UL as a function of temperature is represented. Zone A (300-735 K) shows a gradual decrease with an increase in temperature and Zone B (735-785 K) are attributed to recovery of martensite i.e., reduction in point defects induced by quenching process. Zone C (785-835 K) is attributed to nucleation and formation of Ni 3 (Ti,Mo) coherent intermetallic precipitates. Coarsening and subsequent dissolution process of Ni 3 (Ti,Mo) intermetallic precipitates with increase in temperature is observed from 835 to 905 K (Zone D). The coarsening and partial dissolution of globular precipitation of Fe 2 Mo occurs during aging of maraging steel in the temperature region connecting to Zone E (905-1005 K). At 1005 K, the maraging steel gets transformed to austenite from martensite state, and hence, the velocity takes rapid decrease instead of taking a gradual decrease as marked by double dotted line. (author)

  11. 9-12% Cr heat resistant steels. Alloy design, TEM characterisation of microstructure evolution and creep response at 650 C

    International Nuclear Information System (INIS)

    Rojas Jara, David

    2011-01-01

    This work was carried out aiming to design and characterise 9-12% Cr steels with tailormade microstructures for applications in fossil fuel fired power plants. The investigations concentrated in the design and characterisation of heat resistant steels for applications in high oxidising atmospheres (12% Cr) and 9% Cr alloys for components such as rotors (P91). ThermoCalc calculations showed to be a reliable tool for alloy development. The modeling also provided valuable information for the adjustment of the processing parameters (austenisation and tempering temperatures). Two 12% Cr heat resistant steels with a fine dispersion of nano precipitates were designed and produced supported by thermodynamic modeling (ThermoCalc). A detailed characterisation of the microstructure evolution at different creep times (100 MPa / 650 C / 8000 h) was carried out by scanning transmission electron microscopy (STEM). The results of the microstructure analysis were correlated with the mechanical properties in order to investigate the influence of different precipitates (especially M 23 C 6 carbides) on the creep strength of the alloys. Precipitation of Laves phase and Z-phase was observed after several hundred hours creep time. Very few Z-phase of the type Cr(V,Ta)N nucleating from existing (V,Ta)(C,N) was observed. Both alloys show growth and coarsening of Laves phase, meanwhile the MX carbonitrides present a very slow growth and coarsening rate. Alloys containing Laves phase, MX and M 23 C 6 precipitates show best creep properties. The influence of hot-deformation and tempering temperature on the microstructure evolution on one of the designed 12% Cr alloys was studied during short-term creep at 80-250 MPa and 650 C. Quantitative determination of dislocation density and sub-grain size in the initial microstructure and after creep was investigated by STEM combined with the high-angle annular dark-field detector (HAADF). A correlation between microstructure evolution and creep

  12. 9-12% Cr heat resistant steels. Alloy design, TEM characterisation of microstructure evolution and creep response at 650 C

    Energy Technology Data Exchange (ETDEWEB)

    Rojas Jara, David

    2011-03-21

    This work was carried out aiming to design and characterise 9-12% Cr steels with tailormade microstructures for applications in fossil fuel fired power plants. The investigations concentrated in the design and characterisation of heat resistant steels for applications in high oxidising atmospheres (12% Cr) and 9% Cr alloys for components such as rotors (P91). ThermoCalc calculations showed to be a reliable tool for alloy development. The modeling also provided valuable information for the adjustment of the processing parameters (austenisation and tempering temperatures). Two 12% Cr heat resistant steels with a fine dispersion of nano precipitates were designed and produced supported by thermodynamic modeling (ThermoCalc). A detailed characterisation of the microstructure evolution at different creep times (100 MPa / 650 C / 8000 h) was carried out by scanning transmission electron microscopy (STEM). The results of the microstructure analysis were correlated with the mechanical properties in order to investigate the influence of different precipitates (especially M{sub 23}C{sub 6} carbides) on the creep strength of the alloys. Precipitation of Laves phase and Z-phase was observed after several hundred hours creep time. Very few Z-phase of the type Cr(V,Ta)N nucleating from existing (V,Ta)(C,N) was observed. Both alloys show growth and coarsening of Laves phase, meanwhile the MX carbonitrides present a very slow growth and coarsening rate. Alloys containing Laves phase, MX and M{sub 23}C{sub 6} precipitates show best creep properties. The influence of hot-deformation and tempering temperature on the microstructure evolution on one of the designed 12% Cr alloys was studied during short-term creep at 80-250 MPa and 650 C. Quantitative determination of dislocation density and sub-grain size in the initial microstructure and after creep was investigated by STEM combined with the high-angle annular dark-field detector (HAADF). A correlation between microstructure

  13. The influence of heat treatment and process parameters optimization on hardness and corrosion properties of laser alloyed X12CrNiMo steel

    CSIR Research Space (South Africa)

    Popoola, API

    2016-10-01

    Full Text Available Martensitic stainless steels are used in the production of steam turbine blades but their application is limited due to low hardness and poor corrosion resistance. Laser surface alloying and heat treatment of X12CrNiMo Martensitic stainless steel...

  14. Optimization of Packing Density of M30 Concrete With Steel Slag As Coarse Aggregate Using Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Arivoli M.

    2017-09-01

    Full Text Available Concrete plays a vital role in the design and construction of the infrastructure. To meet the global demand of concrete in future, it is becoming a challenging task to find suitable alternatives to natural aggregates. Steel slag is a by-product of steel making process. The steel slag aggregates are characterized by studying particle size and shape, physical and chemical properties, and mechanical properties as per IS: 2386-1963. The characterization study reveals the better performance of steel slag aggregate over natural coarse aggregate. M30 grade of concrete is designed and natural coarse aggregate is completely replaced by steel slag aggregate. Packing density of aggregates affects the characteristics of concrete. The present paper proposes a fuzzy system for concrete mix proportioning which increases the packing density. The proposed fuzzy system have four sub fuzzy system to arrive compressive strength, water cement ratio, ideal grading curve and free water content for concrete mix proportioning. The results show, the concrete mix proportion of the given fuzzy model agrees with IS method. The comparison of results shows that both proposed fuzzy system and IS method, there is a remarkable increase in compressive strength and bulk density, with increment in the percentage replacement of steel slag.

  15. Structural and phase studies of stainless wire after electroplastic drawing

    International Nuclear Information System (INIS)

    Troitskij, O.A.; Baldokhin, Yu.V.; Kir'yanchev, N.E.; Ryzhkov, V.G.; Kalugin, V.D.; Sokolov, N.V.; Klekovkin, A.A.; Klevtsur, S.A.

    1983-01-01

    Structural and phase properties of the 12Kh18N10T steel wire are studied after usual and electroplastic drawing from 0.40 up to 0.11 mm with 18-22% reduction per pass with passing 250 A/mm 2 electric current. The earlier made observation on a sharp decrease in content of deformation-induced martensite of α-phase takes place in the wire from stainless metastable austenitic steel as a result of electroplastic drawing. Distribution of the remained α-phase by the wire cross section is established

  16. A proposal of parameter to predict biaxial fatigue life for CF8M cast stainless steels

    International Nuclear Information System (INIS)

    Park, Joong Cheul; Kwon, Jae Do

    2005-01-01

    Biaxial low cycle fatigue test was carried out to predict fatigue life under combined axial-torsional loading condition which is that of in-phase and out-of-phase for CF8M cast stainless steels. Fatemi Socie(FS) parameter which is based on critical plane approach is not only one of methods but also the best method that can predict fatigue life under biaxial loading condition. But the result showed that, biaxial fatigue life prediction by using FS parameter with several different parameters for the CF8M cast stainless steels is not conservative but best results. So in this present research, we proposed new fatigue life prediction parameter considering effective shear stress instead of FS parameter which considers the maximum normal stress acting on maximum shear strain and its effectiveness was verified

  17. Microstructural Evolution and Constitutive Relationship of M350 Grade Maraging Steel During Hot Deformation

    Science.gov (United States)

    Chakravarthi, K. V. A.; Koundinya, N. T. B. N.; Narayana Murty, S. V. S.; Nageswara Rao, B.

    2017-03-01

    Maraging steels exhibit extraordinary strength coupled with toughness and are therefore materials of choice for critical structural applications in defense, aerospace and nuclear engineering. Thermo-mechanical processing is an important step in the manufacture of these structural components. This process assumes significance as these materials are expensive and the mechanical properties obtained depend on the microstructure evolved during thermo-mechanical processing. In the present study, M350 grade maraging steel specimens were hot isothermally compressed in the temperature range of 900-1200 °C and in the strain rate range of 0.001-100 s-1, and true stress-true strain curves were generated. The microstructural evolution as a function of strain rate and temperature in the deformed compression specimens was studied. The effect of friction between sample and compression dies was evaluated, and the same was found to be low. The measured flow stress data was used for the development of a constitutive model to represent the hot deformation behavior of this alloy. The proposed equation can be used as an input in the finite element analysis to obtain the flow stress at any given strain, strain rate, and temperature useful for predicting the flow localization or fracture during thermo-mechanical simulation. The activation energy for hot deformation was calculated and is found to be 370.88 kJ/mol, which is similar to that of M250 grade maraging steel.

  18. Fatigue Resistance of GX12CrMoVNbN9-1 Cast Steel after Ageing Process

    Directory of Open Access Journals (Sweden)

    Stanisław MROZIŃSKI

    2014-12-01

    Full Text Available In the present paper, low cycle fatigue behaviour of GX12CrMoVNbN9-1 (GP91 cast steel is presented. Fatigue tests were performed under isothermal conditions at room temperature and at 550 and 600oC, on five levels of total strain amplitude value ɛac = 0.25÷0.60%. The cast steel subject to investigation was in the as-received condition (after heat treatment and after 8000 hours of ageing at the temperature of 600oC. Performed research has shown an insignificant influence of the ageing process on mechanical properties of GP91 cast steel, determined with the static test of tension. Analysis of the performed tests has proved that GP91 cast steel in the as-received condition and after ageing process was characterized by strong cyclic softening without a clear period of stabilization of the hysteresis loop parameters. The fatigue lifetime curves at each temperature were obtained based on Basquin and Coffin – Manson equations. The process of ageing of GP91 cast steel contributed to a decrease in its fatigue life Nf from a few to a few dozen percent, and the level of fatigue life was dependent on the value of strain amplitude ɛac. It has also been stated that the fatigue life Nf of GP91 cast steel is determined by its plastic properties, and the degree of changes in fatigue life Nf was dependent not only on the temperature of testing, but also on the value of strain amplitude ɛac. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6077

  19. Superprotonic KH(PO3H)-SiO2 composite electrolyte for intermediate temperature fuel cells

    NARCIS (Netherlands)

    Bandarenka, A.; Bondarenko, Alexander S.; Zhou, W.; Bouwmeester, Henricus J.M.

    2009-01-01

    Novel thin film composite electrolyte membranes, prepared by dispersion of nano-sized SiO2 particles in the solid acid compound KH(PO3H), can be operated under both oxidizing and reducing conditions. Long-term stable proton conductivity is observed at not, vert, similar140 °C, i.e., slightly above

  20. Plasma Post Oxidation of Plasma Nitrocarburized SKD 61 Steel

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of SKD 61 steel. Plasma nitrocarburizing was conducted for 12 h at 540℃ in the nitrogen,hydrogen and methane atmosphere to produce the ε-Fe,2-3(N,C) phase. The compound layer produced by plasma nitrocarburising was predominantly composed of ε-phase, with a small proportion of γ′-Fe4(N,C) phase.The thickness of the compound layer and the diffusion layer are about 10 μm and about 200μm, respectively.Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at constant temperature of 500℃ for 1 h. The very thin magnetite (Fe3O4) layer of 1-2μm in thickness on top of the compound layer was obtained. Anodic polarization test revealed that plasma nitrocarburizing process contributed a significant improvement of corrosion resistance of SKD 61 steel. However, the corrosion characteristics of the nitrocarburized compound layer was deteriorated by oxidation treatment.

  1. Comparison of the mechanical strength properties of several high-chromium ferritic steels

    International Nuclear Information System (INIS)

    Booker, M.K.; Sikka, V.K.; Booker, B.L.P.

    1981-01-01

    A modified 9 Cr-1 Mo ferritic steel has been selected as an alternative material for breeder reactors. Different 9 Cr-1 Mo steels are already being used commercially in UK and USA and a 9 Cr-2 Mo steel (EM12) is being used commercially in France. The 12% Cr steel alloy HT9 is also often recommended for high-temperature service. Creep-rupture data for all six seels were analyzed to yield rupture life as a function of stress, temperature, and lot-to-lot variations. Yield and tensile strength data for the three 9 Cr-1 Mo materials were also examined. All results were compared with Type 304 stainless steel, and the tensile and creep properties of the modified and British 9 Cr-1 Mo materials were used to calculate allowable stress values S 0 per Section VIII, Division 1 and S/sub m/ per code Case N-47 to section III of the ASME Boiler and Pressure Vessel Code. these values were compared with code listings for American commercial 9 Cr-1 Mo steel, 2 1/4 Cr-1 Mo steel, and Type 304 stainless steel. The conclusion is made that the modified 9 Cr-1 Mo steel displays tensile and creep strengths superior to those of the other ferritic materials examined and is at least comparable to Type 304 stainless steel from room temperature to about 625 0 C. 31 figures

  2. PENDIDIKAN KARAKTER MENURUT K.H. HASYIM ASY’ARI DALAM KITAB ADÂB AL-‘ÂLIM WA AL-MUTA‘ALLIM

    Directory of Open Access Journals (Sweden)

    Sholikah Sholikah

    2015-09-01

    Full Text Available The article deals with K.H. Hasyim Asy’ari’s thought of character education. The result of the study indicates that according to K.H. Hasyim Asy’ari the characters of teachers and students in his work Adab al-‘Âlim wa al-Muta’allim can be classified into three parts, are mentality or character, which should be possessed by teachers and learners: attempts to be done in order to become characterized teachers and learners, and: teaching strategies employed by educators and learning strategies used by learners. These three parts have compatible indicators with the competence of educators stated in UU Sisdiknas (The Legislation of National Educational System year 2003 along with 18 values of character promulgated by Pusat Kurikulum Pengembangan dan Pendidikan Budaya dan Karakter Bangsa. Moreover, according to K.H. Hasyim Asy’ari, the relevance of character education with the context of character education in Indonesia consists of a number of character education elements, namely the meaning and goal of character education, the values of character for both teachers and students, the rationale of character education, the method of character education, the media of character education, and the evaluation of character education

  3. Characteristics of martensite as a function of the M{sub s} temperature in low-carbon armour steel plates

    Energy Technology Data Exchange (ETDEWEB)

    Maweja, Kasonde, E-mail: mawejak@yahoo.fr [Council for Scientific and Industrial Research, CSIR, Materials Science and Manufacturing, PO Box 395, Pretoria 0001 (South Africa); Department of Materials Science and Metallurgical Engineering, University of Pretoria, Pretoria 0002 (South Africa); Stumpf, Waldo [Department of Materials Science and Metallurgical Engineering, University of Pretoria, Pretoria 0002 (South Africa); Berg, Nic van der [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa)

    2009-08-30

    The microstructure, morphology, crystal structure and surface relief of martensite in a number of experimental armour steel plates with different M{sub s} temperatures were analysed. Atomic force microscopy, thin foil transmission electron microscopy and scanning electron microscopy allowed the identification of three groups of low-carbon martensitic armour steels. The investigation showed that the size of individual martensite products (plates or packets, laths or blocks) increases as the M{sub s} temperature increases. Comparison of ballistic performances suggests that the morphology (plate or lath) and size of the individual martensite products dictate the effective 'grain size' in resisting fracture or perforation due to ballistic impact.

  4. Corrosion of path A PCA and 12 Cr-1 MoVW steel in thermally convective lithium

    International Nuclear Information System (INIS)

    Tortorelli, P.F.; DeVan, J.H.

    1984-01-01

    Exposure of path A PCA alloys to thermally convective lithium for 6700 h at 600 and 570 0 C resulted in corrosion reactions that were similar to what is observed for other austenitic alloys exposed under similar conditions. It corroded more rapidly than type 316 stainless steel, and the presence of nitride stringers in PCA did not affect the measured weight losses. Consideration of the weight change and surface analysis data for 12 Cr-1 MoVW steel exposed to thermally convective lithium between 500 and 350 0 C for 10,088 h revealed that reactions with carbon and nitrogen were probably the principal corrosion processes for this alloy in this temperature range. Corrosion was not severe

  5. Standard guide for estimating the atmospheric corrosion resistance of low-alloy steels

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2004-01-01

    1.1 This guide presents two methods for estimating the atmospheric corrosion resistance of low-alloy weathering steels, such as those described in Specifications A242/A242M, A588/A588M, A606 Type 4, A709/A709M grades 50W, HPS 70W, and 100W, A852/A852M, and A871/A871M. One method gives an estimate of the long-term thickness loss of a steel at a specific site based on results of short-term tests. The other gives an estimate of relative corrosion resistance based on chemical composition. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

  6. Paraequilibrium Carburization of Duplex and Ferritic Stainless Steels

    Science.gov (United States)

    Michal, G. M.; Gu, X.; Jennings, W. D.; Kahn, H.; Ernst, F.; Heuer, A. H.

    2009-08-01

    AISI 301 and E-BRITE stainless steels were subjected to low-temperature (743 K) carburization experiments using a commercial technology developed for carburization of 316 austenitic stainless steels. The AISI 301 steel contained ~40 vol pct ferrite before carburization but had a fully austenitic hardened case, ~20- μm thick, and a surface carbon concentration of ~8 at. pct after treatment; this “colossal” paraequilibrium carbon supersaturation caused an increase in lattice parameter of ~3 pct. The E-BRITE also developed a hardened case, 12- to 18- μm thick, but underwent a more modest (~0.3 pct) increase in lattice parameter; the surface carbon concentration was ~10 at. pct. While the hardened case on the AISI 301 stainless steel appeared to be single-phase austenite, evidence for carbide formation was apparent in X-ray diffractometer (XRD) scans of the E-BRITE. Paraequilibrium phase diagrams were calculated for both AISI 301 and E-BRITE stainless steels using a CALPHAD compound energy-based interstitial solid solution model. In the low-temperature regime of interest, and based upon measured paraequilibrium carbon solubilities, more negative Cr-carbon interaction parameters for austenite than those in the current CALPHAD data base may be appropriate. A sensitivity analysis involving Cr-carbon interaction parameters for ferrite found a strong dependence of carbon solubility on relatively small changes in the magnitude of these parameters.

  7. Stainless steels and nuclear industry: last advanced progress

    International Nuclear Information System (INIS)

    Leveque, Robert; Saleil, Jean; Dhers, Jean

    2013-01-01

    70 participants have attended the colloquium in Saint Etienne last May 2013. 12 conferences have been presented and are summarized in this journal article. The different thema developed were: stainless steels in the different reactors, degradation by irradiation, evolution of manufacturing processes, innovative solutions and modeling of grain growth and control. (O.M.)

  8. Study on the process of calibration and deep centring of blanks

    International Nuclear Information System (INIS)

    Potapov, I.N.; Romantsev, B.A.; Popov, V.A.; Volodin, V.V.; Goncharuk, A.V.

    1985-01-01

    Process of calibration and deep centring of blanks before broaching is developed and studied. Investigations are performed at a semi-industrial screw rolling mill MISiS-100 T. Blanks made of 40Kh, 60, 50, 45KhN2MFA, 30KhGSNA steels 80, 85, and 90 mm in diameter and 300 mm long were calibrated and centered after heating in a furnace to a depth of 200 mm at shafts and faces with different calibration. 30KhN2MFA steel is chosen for face material; heat treatment is conducted under the following conditions: heating up to 950-1000 deg C and hold-up during 30-35 min with the following cooling in the air. The above experimental investigations reveal that the process of calibration and deep centring accomplished at a three-shaft screw rolling mill is rather stable and provides a high accuracy of centering hollow marking

  9. The occurrence of an ordered fcc phase in neutron irradiated M316 stainless steel

    International Nuclear Information System (INIS)

    Cawthorne, C.; Brown, C.

    1977-01-01

    A small precipitate giving a superlattice type diffraction pattern has been observed in M316 type stainless steel irradiated in the Dounreay Fast Reactor. The precipitate was observed in cold worked and solution treated samples which were unstressed and irradiated below 540 0 C, but not in those irradiated above this temperature or in the stressed samples. (B.D.)

  10. 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

  11. Age-hardening susceptibility of high-Cr ODS ferritic steels and SUS430 ferritic steel

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Dongsheng, E-mail: chen.dongsheng85@gmail.com [Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Kimura, Akihiko; Han, Wentuo; Je, Hwanil [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2015-10-15

    Highlights: • The role of oxide particles in α/α′ phase decomposition behavior; microstructure of phase decomposition observed by TEM. • The characteristics of ductility loss caused by age-hardening. • Correlation of phase decomposition and age-hardening explained by dispersion strengthened models. • Age-hardening susceptibility of ODS steels and SUS430 steel. - Abstract: The effect of aging on high-Cr ferritic steels was investigated with focusing on the role of oxide particles in α/α′ phase decomposition behavior. 12Cr-oxide dispersion strengthened (ODS) steel, 15Cr-ODS steel and commercial SUS430 steel were isothermally aged at 475 °C for up to 10,000 h. Thermal aging caused a larger hardening in SUS430 than 15Cr-ODS, while 12Cr-ODS showed almost no hardening. A characteristic of the ODS steels is that the hardening was not accompanied by the significant loss of ductility that was observed in SUS430 steel. After aging for 2000 h, SUS430 steel shows a larger ductile–brittle transition temperature (DBTT) shift than 15Cr-ODS steel, which suggests that the age-hardening susceptibility is lower in 15Cr-ODS steel than in conventional SUS430 steel. Thermal aging leaded to a large number of Cr-rich α′ precipitates, which were confirmed by transmission electron microscopy (TEM). Correlation of age-hardening and phase decomposition was interpreted by Orowan type strengthening model. Results indicate that oxide particles cannot only suppress ductility loss, but also may influence α/α′ phase decomposition kinetics.

  12. Corrosion resistance of stainless steels and high Ni-Cr alloys to acid fluoride wastes

    International Nuclear Information System (INIS)

    Smith, H.D.; Mackey, D.B.; Pool, K.H.; Schwenk, E.B.

    1992-04-01

    TRUEX processing of Hanford Site waste will utilize potentially corrosive acid fluoride processing solutions. Appropriate construction materials for such a processing facility need to be identified. Toward this objective, candidate stainless steels and high Ni-Cr alloys have been corrosion tested in simulated acid fluoride process solutions at 333K. The high Ni-Cr alloys exhibited corrosion rates as low as 0.14 mm/y in a solution with an HF activity of about 1.2 M, much lower than the 19 to 94 mm/y observed for austenitic stainless steels. At a lower HF activity (about 0.008 M), stainless steels display delayed passivation while high Ni-Cr alloys display essentially no reaction

  13. Polarization mechanism and ferroelectric instability in KH2PO4

    International Nuclear Information System (INIS)

    Koval, S.; Migoni, R.L.; Kohanoff, J.; Bussmann-Holder, A.

    2000-11-01

    The polarization mechanism and the origin of ferroelectricity in KH 2 PO 4 (KDP) are studied by first-principles electronic structure calculations. In the low-temperature phase, the collective off-center ordering of the protons is accompanied by an electronic charge delocalization from the near and localization at the far oxygen within the O-H...0 bonds. Electrostatic forces, then, push the K + ions towards off-center positions, and induce a macroscopic polarization. The analysis of the correlation between different geometrical and electronic quantities, in connection with experimental data, supports the idea that the role of tunnelling in isotopic effects is irrelevant. Instead, geometrical quantum effects appear to play a central role. (author)

  14. Nitride and carbide thin films as hydrogen permeation barrier on Manet steel

    International Nuclear Information System (INIS)

    Benamati, G.; Checchetto, R.; Bonelli, M.; Gratton, L.M.; Guzman, L.; Miotello, A.; Terlain, A.

    1995-01-01

    TiC / TiN bilayers, ∼ 1.2 μm thick, were deposited on Manet II steel by the ion beam assisted deposition technique to investigate the possible use of this ceramic coating as hydrogen barrier. Hydrogen permeation experiments in the temperature range 470-570 K showed indeed that this coating is a very efficient barrier to the hydrogen permeation being able to reduce the hydrogen flux up to two order of magnitude with respect to the uncoated steel. Preliminary compatibility tests between coated Manet II and Pb-17Li showed no attack of Pb-17Li to the steel. (orig.)

  15. On the microstructural basis of creep strength and creep-fatigue interaction in 9-12 % Cr steels for application in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Chilukuru, H

    2007-03-06

    As part of the efforts of preserving the environment it is necessary to reduce of the CO2 emissions from power plants. This can be done by increasing the plant efficiency. Research groups around the world are engaged in developing new steels capable of sustaining higher stresses and temperatures envisaged for high-efficiency power plants. Research carried out in Europe is organized within the COST Programme (Co-Operation in Science and Technology) aiming at replacing the conventional steels of type X20CrMoV121 by the new class of 9-12% Cr-steels with modified composition. The resistance of materials against deformation at elevated temperatures depends on their microstructure. Frequently in 9-12% Cr-steels improved short-term creep properties do not persist in the long-term service [1, 2, 3, 4, 5, 6]. This is related with insufficient microstructural stability. Hardening contributions in 9-12% Cr-steels come from solute atoms of the ferritic matrix, from dislocations, and from precipitates of foreign phases within the matrix. The term ''carbide stabilized substructure hardening'' of 9-12% Cr steels [7, 8] indicates that the hardening contributions are interdependent. The dislocations are the carriers of plastic deformation. They interact with each other, with solute atoms and with precipitates. The dislocation-dislocation interaction leads to formation of planar dislocation networks constituting low-angle boundaries. They form a subgrain structure within the grains. At present, a full and detailed understanding of the effects exerted by the different components of microstructure on creep strength is still lacking. The present work makes a contribution to the efforts of understanding the microstructural basis of creep strength and of creep-fatigue interaction by transmission electron microscopic structure investigations coupled with creep tests. Investigations by transmission electron microscopy (TEM) were carried out with regard to hardening by subgrain boundaries

  16. On the microstructural basis of creep strength and creep-fatigue interaction in 9-12 % Cr steels for application in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Chilukuru, H.

    2007-03-06

    As part of the efforts of preserving the environment it is necessary to reduce of the CO2 emissions from power plants. This can be done by increasing the plant efficiency. Research groups around the world are engaged in developing new steels capable of sustaining higher stresses and temperatures envisaged for high-efficiency power plants. Research carried out in Europe is organized within the COST Programme (Co-Operation in Science and Technology) aiming at replacing the conventional steels of type X20CrMoV121 by the new class of 9-12% Cr-steels with modified composition. The resistance of materials against deformation at elevated temperatures depends on their microstructure. Frequently in 9-12% Cr-steels improved short-term creep properties do not persist in the long-term service [1, 2, 3, 4, 5, 6]. This is related with insufficient microstructural stability. Hardening contributions in 9-12% Cr-steels come from solute atoms of the ferritic matrix, from dislocations, and from precipitates of foreign phases within the matrix. The term ''carbide stabilized substructure hardening'' of 9-12% Cr steels [7, 8] indicates that the hardening contributions are interdependent. The dislocations are the carriers of plastic deformation. They interact with each other, with solute atoms and with precipitates. The dislocation-dislocation interaction leads to formation of planar dislocation networks constituting low-angle boundaries. They form a subgrain structure within the grains. At present, a full and detailed understanding of the effects exerted by the different components of microstructure on creep strength is still lacking. The present work makes a contribution to the efforts of understanding the microstructural basis of creep strength and of creep-fatigue interaction by transmission electron microscopic structure investigations coupled with creep tests. Investigations by transmission electron microscopy (TEM) were carried out with regard to hardening by

  17. Synergistic effect of iodide ion addition on the inhibition of mild steel corrosion in 1 M HCl by 3-amino-2-methylbenzylalcohol

    Energy Technology Data Exchange (ETDEWEB)

    Obot, I.B., E-mail: obot@kfupm.edu.sa; Madhankumar, A.

    2016-07-01

    The inhibition of mild steel corrosion in 1 M HCl aqueous solution by 3-amino-2-methylbenzylalcohol (AMBA) was investigated using weight loss, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP) and cyclic voltammametry (CV) techniques. Attenuated total reflectance infrared spectroscopy (ATR-IR), contact angle (CA) and scanning electron microscopy (SEM) measurements were carried out to confirm the adsorption of AMBA on mild steel surface. Computer simulations using density functional theory (DFT) and Monte Carlo methodologies were further employed to provide insights into the mechanism of interaction between the inhibitor and the steel surface. All the results confirmed that AMBA is a good corrosion inhibitor for mild steel in 1 M HCl. The addition of NaI was found to increase the inhibition effect of AMBA on mild steel to a considerable extent. DFT results reveal that the N atom together with the π-systems in the aromatic ring were the active sites for the interaction of AMBA with steel surface. Furthermore, the negative value of the adsorption energy obtained from the Monte Carlo simulation indicates the stability of the adsorbed inhibitor film on the steel surface. - Graphical abstract: EIS spectra and adsorption configuration of AMBA on Fe (110). - Highlights: • 3-amino-2-methylbenzylalcohol inhibit mild steel corrosion in acid medium. • ATR-IR, contact angle, SEM, were used for steel surface characterization. • DFT and Monte Carlo simulations provide atomic and molecular level insights. • The theoretical data clearly support the experimental results obtained.

  18. Plasma-induced surface degradation in 304 stainless steel used for TRIAM-1M limiter

    International Nuclear Information System (INIS)

    Tsukuda, N.; Kuramoto, E.; Tokunaga, K.; Muroga, T.; Yoshida, N.; Itoh, S.

    1994-01-01

    Surface degradation in a 304 stainless steel limiter of TRIAM-1M by long-pulse discharge during long period operation has been examined by means of X-ray diffraction, scanning electron microscopy and dynamical microindentation tests. Particular exfoliation and hardening of the surface of the electron drift side were observed. These result from the formation of α prime martensite induced by hydrogen in the plasma. The stability of the martensitic phase has been studied by annealing experiments on the cathodically hydrogen charged 316 stainless steel by X-ray diffraction. Both ε and α prime martensites were formed by 22 h cathodic charging. The former reverts to γ-phase and/or converts to α prime martensite below 723 K and the latter reverts to γ-phase below 923 K, repectively. ((orig.))

  19. Radiation damage structure in irradiated and annealed 440 WWER-Type reactor pressure vessel steels

    International Nuclear Information System (INIS)

    Kocik, J.; Keilova, E.

    1993-01-01

    A review of irradiation damages in WWER-type RPV steels based on conventional Transmission Electron Microscopy investigations in a power reactor and a research reactor, is presented; the samples consist in Cr-Mo-V ferritic steel (15Kh2MFA type). The visible part of radiation-induced defects consists of very fine vanadium carbide precipitates, small dislocation loops and black dots (presumably corresponding to clusters and particle embryos formed from vacancies and solute-atoms (vanadium, copper, phosphorus) and carbon associated with vanadium. Radiation-induced defects are concentrated at dislocation substructure during irradiation in a power reactor, revealing the role of radiation-enhanced diffusion in damage structure forming process. Contrarily, the distribution of defects resulting from annealing of specimens irradiated in the research reactor is pre-determined by an homogenous distribution of radiation-induced defects prior to annealing. Increasing the number of re-irradiation and annealing cycles, the amount of dislocation loops among all defects seems to be growing. Simultaneously, the dislocation substructure recovers considerably. (authors). 14 refs., 11 figs., 3 tabs

  20. Radiation damage structure in irradiated and annealed 440 WWER-Type reactor pressure vessel steels

    Energy Technology Data Exchange (ETDEWEB)

    Kocik, J; Keilova, E [Czech Nuclear Society, Prague (Czech Republic)

    1994-12-31

    A review of irradiation damages in WWER-type RPV steels based on conventional Transmission Electron Microscopy investigations in a power reactor and a research reactor, is presented; the samples consist in Cr-Mo-V ferritic steel (15Kh2MFA type). The visible part of radiation-induced defects consists of very fine vanadium carbide precipitates, small dislocation loops and black dots (presumably corresponding) to clusters and particle embryos formed from vacancies and solute-atoms (vanadium, copper, phosphorus) and carbon associated with vanadium. Radiation-induced defects are concentrated at dislocation substructure during irradiation in a power reactor, revealing the role of radiation-enhanced diffusion in damage structure forming process. Contrarily, the distribution of defects resulting from annealing of specimens irradiated in the research reactor is pre-determined by an homogenous distribution of radiation-induced defects prior to annealing. Increasing the number of re-irradiation and annealing cycles, the amount of dislocation loops among all defects seems to be growing. Simultaneously, the dislocation substructure recovers considerably. (authors). 14 refs., 11 figs., 3 tabs.

  1. Compactibility of atomized high-speed steel and steel 3 powders

    International Nuclear Information System (INIS)

    Kulak, L.D.; Gavrilenko, A.P.; Pikozh, A.P.; Kuz'menko, N.N.

    1985-01-01

    Spherical powders and powders of lammellar-scaly shape of high-speed R6M5K5 steel and steel 3 produced by the method of centrifugal atomization of a rotating billet under conditions of cold pressing in steel moulds are studied for thier compactability. Compacting pressure dependnences are establsihed for density of cold-pressed compacts of spherical and scaly powders. The powders of lammellar-scaly shape both of high-speed steel and steel 3 are found to possess better compactibility within a wide range of pressures as compared to powders of spherical shape. Compacts of the lammellar-scaly powders possess also higher mechanical strength

  2. Effect of test temperature on the fatigue strength of the 12GN2MFAYu tempered steel

    International Nuclear Information System (INIS)

    Goritskij, V.M.; Terent'ev, V.F.; Bobyleva, L.A.

    1979-01-01

    The cyclic strength, variation of dislocation structure and fractography of specimen fractures were investigated depending on testing temperature. The specimens were tested at temperatures of 20, 350, 450, 550 deg C. The increase of testing temperature, according to the experimental data obtained, is accompanied by an insignificant reduction of fatigue strength. The testing temperature in the range from 350 to 550 deg C has a weak effect on the fatigue strength of the quenched and tempered steel. A change in the dislocation structure occurs under all tested temperatures in the 12 GN2MFAYu steel during fatigue. The intensity of the rearrangement of dislocation structure increases as the testing temperature increases to 550 deg C causing a decrease of the limited life-time at increased stress amplitudes

  3. KH 2PO4 as a novel catalyst for regioselective monobromination of aralkyl ketones using N-bromosuccinimide: a green methodology

    Directory of Open Access Journals (Sweden)

    P. Md. Khaja Mohinuddin

    2015-08-01

    Full Text Available A simple, regioselective and green method has been developed for the preparation of monobrominated ketones from various aralkyl ketones by using N-bromosuccinimide in presence of KH 2PO 4 in EtOH at reflux temperature. The present method is of short reaction time and simple with excellent isolated yields of products. The use of eco-friendly solvent, reuse of organic waste (succinimide and recyclable catalyst used for 4 times without loss of activity are advantageous. This is the first example of the use of KH 2PO 4 as a useful catalyst in organohalogen chemistry and the present method meets reduce-reuse-recycle (RRR principle towards development of green protocol.

  4. Kinetic secondary deuterium isotope effect in addition of nucleophile to m-bromobenzaldehyde

    International Nuclear Information System (INIS)

    Amaral, L. do; Rossi, M.H.

    1985-01-01

    The kinetic secondary deuterium isotope effects, KD/KH for hydrated proton catalyzed addition of semicarbazide, methoxyamine and hydroxylamine to m-bromobenzaldehyde is studied. The nature of the nucleophile, addition of the carbonyl group and the chemical reactions are evaluated. (M.J.C.) [pt

  5. Diagnostics of metal state in steam lines

    International Nuclear Information System (INIS)

    Gofman, Yu.M.; Kazantseva, N.S.; Losev, L.Ya.; Nevolina, G.S.

    1986-01-01

    A series of micropore detection methods is suggested: light microscopy, electron microscopy, hydrostatic weighing; and comparative investigations of pore-formation processes in 12Kh1MF steel steam lines, which have operated for about 100 thousand hours at t=550 deg C and 47-55 MPa stresses are conducted using these methods. It is shown, that electron microscpy method can be applied at the early stages damaging, when embrionic micropores of 0.1 μm in size appear. Optical metallography allows one to detect pores of about 1 μm in size. Damage in density using the hydrostatic weighing method is estimated in the following way: at creep stages 1-2-0.1; at stage 3-0.4-0.6; at predestruction stage the degree of damage equals to 0.7-0.8

  6. INFLUENCE OF MODIFICATION ON THE STRUCTURE AND CHARACTERISTICS OF THE STAINLESS STEEL 12X18H10TL

    Directory of Open Access Journals (Sweden)

    I. V. Zemskov

    2004-01-01

    Full Text Available There are given the results of investigation of influence of modification by ferrocerium, FS30RZM30B, FSMG, modifier MN, developed in BNTU, ferromolybdenum on the structure and characteristics of the steel 12X18H10TL.

  7. Microstructural investigations of fatigued 12% Cr-steel 1.4914 (X 18 Cr Mo V Nb 12 1)

    International Nuclear Information System (INIS)

    Gersinska, R.

    1992-10-01

    The low cycle fatigue properties of a tempered steel X18 Cr Mo V Nb 12 1 (DIN 1.4914) have been investigated at different temperatures, strain amplitudes, mean strains and strain rates. The role of martensite lath structure and of precipitates and dislocations on the strengthening mechanisms and fatigue damage have been analysed. Plastic deformation results in a slip band formation on the surface and in a cellular dislocation structure in the interior of the specimens. A reduced strain rate is causing lower stress amplitudes and greater cells at higher temperatures. At lower temperatures the influence of strain rate is small. Fatigue mechanisms are soon dominant at lower strain rates. REM-investigations of the specimen surfaces are revealing the development of cracks at slip bands. The cracks start always at the surfaces of the specimen, and they are transcristalline in nature. The influence of the ageing temperature has been investigated. A reduced ageing temperature of 600degC results in a higher dislocation density and a lower martensite lath distance in the undeformed material. Strain ageing was initially observed in tensile experiments. The influence of dynamic strain ageing on the mechanical properties and the microstructure of tempered steel 1.4914 is investigated. A correlation of mechanical and microstructural data has been performed. (orig./MM) [de

  8. Measurement of trace elements in KH2PO4 crystals by x-ray fluorescence spectrometry

    International Nuclear Information System (INIS)

    Ryon, R.W.; Duewer, T.I.

    1981-02-01

    A non-destructive method is described for the quantitative measurement of impurities in KDP (KH 2 PO 4 ) crystals. Part per million concentrations of impurities can be determined with good accuracy in about one hour of instrument time. An energy dispersive x-ray spectrometer is used. Both the crystals and the solutions from which they are grown may be analyzed

  9. Behavior of the elements in the mechanically alloyed and cast ferritic steels and a type 316 stainless steel in a flowing sodium environment

    International Nuclear Information System (INIS)

    Suzuki, T.; Mutoh, I.

    1988-01-01

    Sodium corrosion behavior of a mechanically alloyed ferritic steel, dispersion-strengthened with addition of Y 2 0 3 and Ti, two kinds of melted/cast ferritic steels and a Type 316 stainless steel was examined by using a non-isothermal sodium loop system, constructed of another Type 316 stainless steel, with a direct resistance electrical heater. The sodium conditions were 675 0 C, 4.0 m/s in velocity and 1-2 ppm oxygen concentration and a cumulative exposure time of the specimens was about 3000 h. The absorption of Ni and selective dissolution of Cr played an important role in the corrosion of the mechanically alloyed ferritic steel as in the case of the cast ferritic steels. However, the region of Ni absorption and Cr diminution was deeper than that of the cast ferritic steels. Peculiar finding for the mechanically alloyed ferritic steel was the corroded surface with irregularly shaped protuberance, that might be related with formation of sodium titanate, and the absorption of carbon and nitrogen to form carbide and nitride of titanium. It seems that these facts resulted in the irregular weight loss of the specimens, which depended on the downstream position and the cumulative exposure time. However, the tensile properties of the mechanically alloyed ferritic steel did not noticeably change by the sodium exposure

  10. Study of the M23C6 precipitation in AISI 304 stainless steel by small angle neutron scattering

    International Nuclear Information System (INIS)

    Boeuf, A.; Caciuffo, R.G.M.; Institut Max von Laue - Paul Langevin, 38 - Grenoble; Ancona Univ.; Melone, S.; Puliti, P.; Rustichelli, F.; Institut Max von Laue - Paul Langevin, 38 - Grenoble; Ancona Univ.; Coppola, R.

    1985-01-01

    The results of some small-angle neutron scattering (SANS) experiments on M 23 C 6 (M=Fe, Cr) carbide precipitation in AISI 304 stainless steel, aged at different temperatures during different times, are presented. The total volume fraction, the total surface of precipitates per unit sample volume and the size distribution functions of the M 23 C 6 carbides were determined. (orig.)

  11. Opuntia ficus-indica Extract as Green Corrosion Inhibitor for Carbon Steel in 1 M HCl Solution

    Directory of Open Access Journals (Sweden)

    J. P. Flores-De los Ríos

    2015-01-01

    Full Text Available The effect of Opuntia ficus-indica (Nopal as green corrosion inhibitor for carbon steel in 1 M HCl solution has been investigated by using weight loss tests, potentiodynamic polarization curves, and electrochemical impedance spectroscopy measurements. Also, scanning electron microscopy (SEM and Fourier transform infrared spectroscopy (FT-IR analysis were performed. The inhibitor concentrations used ranged from 0 to 300 ppm at 25, 40, and 60°C. Results indicated the inhibition efficiency increases with increasing extract concentration and decreases with the temperature, and the inhibitor acted as a cathodic-type inhibitor which is physically absorbed onto the steel surface. In fact, the adsorption of the inhibitor on the steel surface follows the Langmuir adsorption isotherm, indicating monolayer adsorption. The presence of heteroatoms such as C, N, and O and OH groups were responsible for the corrosion inhibition.

  12. Electrochemical machining of internal built-up surfaces of large-sized vessels for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ryabchenko, N N; Pulin, V Ya [Vsesoyuznyj Proektno-Tekhnologicheskij Inst. Atomnogo Mashinostroeniya i Kotlostroeniya, Rostov-na-Donu (USSR)

    1977-01-01

    Electrochemical machining (ECM) has been employed for finishing of mechanically processed inner surfaces of large lateral parts of construction bodies with welded 0Kh18N10T steel overlayer. The finishing technology developed reduces the surface roughness from 10 mcm to the standard 2.5 mcm at the efficiency of machining of 2-4 m/sup 2/ per hour.

  13. Effect of cold deformation on latent energy value and high-temperature mechanical properties of 12Cr18Ni10Ti steel

    International Nuclear Information System (INIS)

    Maksimkin, O.P.; Shiganakov, Sh.B.; Gusev, M.N.

    1997-01-01

    Energetic and magnetic characteristics and also the high-temperature mechanical properties depending on the preliminary cold deformation of 12Cr18Ni10Ti steel are presented. It is shown that the value of storage energy in the steel has being grown with increase of the deformation. The rate of its growth has been increased after beginning of martensitic γ→α'- transformation when value of comparative storage energy at first decreased and then has been stay practically constant. Level of mechanical properties of the steel at 1073 K has been determined not only by value of cold deformation but and structural reconstruction corresponding to deformations 35-45% and accompanying with α'-phase martensite formation and change of energy accumulating rate. Preliminary cold deformation (40-60 %) does not improve high- temperature plasticity of steel samples implanted by helium. refs. 7, figs. 2

  14. 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-Q12 in vitro and in vivo

    International Nuclear Information System (INIS)

    Bernard, Bert F.; Krenning, Eric P.; Breeman, Wout A. P.; Ensing, Geert; Benjamins, Harry; Bakker, Willem H.; Visser, Theo J.; Jong, Marion de

    1998-01-01

    The aim of this study was to compare uptake of 99m Tc-MIBI, 99m Tc-tetrofosmin and 99m Tc-Q12 in vitro and biodistribution in vivo in rats. In vitro, uptake decreased in the order MIBI→tetrofosmin→Q12. Uptake of MIBI and tetrofosmin, but not of Q12, in cultured tumor cells was dependent on the plasma membrane and mitochondrial potential. In vivo, heart uptake of all three compounds was high and stable. Tumor uptake decreased in the order MIBI→Q12→tetrofosmin and the tumor/blood ratio in the order MIBI→tetrofosmin→Q12

  15. Future directions for ferritic/martensitic steels for nuclear applications

    International Nuclear Information System (INIS)

    Klueh, R.L.; Swindeman, R.W.

    2000-01-01

    High-chromium (7-12% Cr) ferritic/martensitic steels are being considered for nuclear applications for both fission and fusion reactors. Conventional 9-12Cr Cr-Mo steels were the first candidates for these applications. For fusion reactors, reduced-activation steels were developed that were patterned on the conventional steels but with molybdenum replaced by tungsten and niobium replaced by tantalum. Both the conventional and reduced-activation steels are considered to have an upper operating temperature limit of about 550degC. For improved reactor efficiency, higher operating temperatures are required. For ferritic/martensitic steels that could meet such requirements, oxide dispersion-strengthened (ODS) steels are being considered. In this paper, the ferritic/martensitic steels that are candidate steels for nuclear applications will be reviewed, the prospect for ODS steel development and the development of steels produced by conventional processes will be discussed. (author)

  16. Investigation programme and procedure for creep and long-term rupture strength in materials with accounting for stress deviator and loading history

    International Nuclear Information System (INIS)

    Mozharovskaya, T.N.

    1984-01-01

    A programme and procedure are given to study 08Kh18N9 steel at 600 deg C and 15Kh2MFA steel at 550 deg C for creep and long-term strength at different parameters of proportional loading as well as at different parameters under loading in two-link irregular trajectories. This makes it possible to estimate the effect of the kind of a stress deviator, history and prehistory of loading on plastic deformation in creep and on failure under long-term loading

  17. Investigation programme and procedure for creep and long-term rupture strength in materials with accounting for stress deviator and loading history

    Energy Technology Data Exchange (ETDEWEB)

    Mozharovskaya, T N [AN Ukrainskoj SSR, Kiev. Inst. Problem Prochnosti

    1984-11-01

    A programme and procedure are given to study 08Kh18N9 steel at 600 deg C and 15Kh2MFA steel at 550 deg C for creep and long-term strength at different parameters of proportional loading as well as at different parameters under loading in two-link irregular trajectories. This makes it possible to estimate the effect of the kind of a stress deviator, history and prehistory of loading on plastic deformation in creep and on failure under long-term loading.

  18. Nitride and carbide thin films as hydrogen permeation barrier on MANET steel

    International Nuclear Information System (INIS)

    Benamati, G.

    1994-01-01

    TiC/TiN bilayers, - 1.2 μm thick, were deposited on Manet II steel by the ion beam assisted deposition technique to investigate the possible use of this ceramic coating as hydrogen barrier. Hydrogen permeation experiments in the temperature range 470-570 K showed indeed that this coating is a very efficient barrier to the hydrogen permeation being able to reduce the hydrogen flux up to two order of magnitude with respect to the uncoated steel. Preliminary compatibility tests between coated Manet II and Pb-17Li showed no attack of Pb-17Li to the steel. (author) 8 refs.; 2 figs.; 1 tab

  19. Investigations on grain boundary segregation energy of phosphorus in 12Cr1MoV steel under elastic stress

    Czech Academy of Sciences Publication Activity Database

    Zheng, L.; Fu, Y.; Lejček, Pavel; Song, S.; Schmitz, G.; Meng, Y.

    2016-01-01

    Roč. 18, č. 4 (2016), 506-510 ISSN 1438-1656 R&D Projects: GA ČR GAP108/12/0144 Institutional support: RVO:68378271 Keywords : grain boundary segregation, * stress effect, * phosphorus, * steel Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.319, year: 2016

  20. Preparation of porous diatomite-templated carbons with large adsorption capacity and mesoporous zeolite K-H as a byproduct.

    Science.gov (United States)

    Liu, Dong; Yuan, Weiwei; Deng, Liangliang; Yu, Wenbin; Sun, Hongjuan; Yuan, Peng

    2014-06-15

    In this study, KOH activation was performed to enhance the porosity of the diatomite-templated carbon and to increase its adsorption capacity of methylene blue (MB). In addition to serving as the activation agent, KOH was also used as the etchant to remove the diatomite templates. Zeolite K-H was synthesized as a byproduct via utilization of the resultant silicon- and potassium-containing solutions created from the KOH etching of the diatomite templates. The obtained diatomite-based carbons were composed of macroporous carbon pillars and tubes, which were derived from the replication of the diatomite templates and were well preserved after KOH activation. The abundant micropores in the walls of the carbon pillars and tubes were derived from the break and reconfiguration of carbon films during both the removal of the diatomite templates and KOH activation. Compared with the original diatomite-templated carbons and CO2-activated carbons, the KOH-activated carbons had much higher specific surface areas (988 m(2)/g) and pore volumes (0.675 cm(3)/g). Moreover, the KOH-activated carbons possessed larger MB adsorption capacity (the maximum Langmuir adsorption capacity: 645.2 mg/g) than those of the original carbons and CO2-activated carbons. These results showed that KOH activation was a high effective activation method. The zeolite K-H byproduct was obtained by utilizing the silicon- and potassium-containing solution as the silicon and potassium sources. The zeolite exhibited a stick-like morphology and possessed nanosized particles with a mesopore-predominant porous structure which was observed by TEM for the first time. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Flexural behaviour and punching shear of selfcompacting concrete ribbed slab reinforced with steel fibres

    Directory of Open Access Journals (Sweden)

    Ahmad Hazrina

    2017-01-01

    Full Text Available This paper investigates the effects of steel fibres as a replacement to the conventional reinforcement under flexural behaviour and punching shear in self-compacting (SCC ribbed slab reinforced with steel fibres. Four ribbed slabs with similar dimensions of 2.8 m length × 1.2 m width and 0.2m thickness were constructed. Two of the samples were considered as control samples (conventionally reinforced with reinforcement bars and welded mesh while another two samples were fully reinforced with 1% (80 kg/m3 volume of steel fibres incorporated to the SCC mix. For the flexural behaviour study, the ribbed slab samples were subjected to two line loads under four point bending. Meanwhile, for the punching shear analysis, the ribbed slab samples were subjected to a point load to simulate loading from the column. The analysis of the experimental results displayed that steel fibres incorporation had been found to effectively delay the first crack occurrence under both flexural and punching shear. The steel fibre replacement has been proven to be able to sustain up to 80% and 73% of the ultimate load resistance for flexural and punching shear, respectively, in comparison to conventionally reinforced ribbed slab structure. The visual observation carried out during the experiment exhibited similar failure mode for both steel fibre reinforced and control samples. This was observed for both flexural and punching shear samples. Overall, it can be concluded that the steel fibres had displayed a promising potential to effectively replace the conventional reinforcements.

  2. Movement of liquid metal in welding bath during welding in longitudinal magnetic field

    International Nuclear Information System (INIS)

    Kovalev, I.M.; Rybakov, A.S.

    1977-01-01

    The specific features are considered of liquid metal flow in a bath during welding of steel 12Kh18N10T plates with a non-consumable electrode in argon under interaction of the arc and bath with a longitudinal constant magnetic field. In controlling the velocity field of metal flow, the longitudinal magnetic field permits to form a seam at automatic welding of horizontal joints on a vertical plane

  3. USSR and Eastern Europe Scientific Abstracts, Engineering and Equipment, Number 31

    Science.gov (United States)

    1977-04-18

    HYDROTURBINE BLADES TRUDY ALTAYSKOGO POLITEKHNICHESKOGO INSTITUTA [Works of the Altay Poly- technic Institute] in Russian No 50, 1975 pp 59-65...developed, and suggested for explosive 66 coating of hydroturbine blades, a new cavitation-resistant martensite- hardening steel type 00KH12SH8MTYU (E17...which demonstrates the prospects of its use in hydroturbine design for parts of hydromachinery, subjected to a cavitation effect. The economy of

  4. A two-stage constitutive model of X12CrMoWVNbN10-1-1 steel during elevated temperature

    Science.gov (United States)

    Zhu, Luobei; He, Jianli; Zhang, Ying

    2018-02-01

    In order to clarify the competition between work hardening (WH) caused by dislocation movements and the dynamic softening result from dynamic recovery (DRV) and dynamic recrystallization (DRX), a new two-stage flow stress model of X12CrMoWVNbN10-1-1 (X12) ferrite heat-resistant steel was established to describe the whole hot deformation behavior. And the parameters were determined by the experimental data operated on a Gleeble-3800 thermo- mechanical simulation. In this constitutive model, a single internal variable dislocation density evolution model is used to describe the influence of WH and DRV to flow stress. The DRX kinetic dynamic model can express accurately the contribution of DRX to the decline of flow stress, which was established on the Avrami equation. Furthermore, The established new model was compared with Fields-Bachofen (F-B) model and experimental data. The results indicate the new two-stage flow stress model can more accurately represent the hot deformation behavior of X12 ferrite heat-resistant steel, and the average error is only 0.0995.

  5. Biomechanical cadaveric comparison of patellar ligament suture protected by a steel cable versus a synthetic cable.

    Science.gov (United States)

    Bouget, P; Breque, C; Beranger, J S; Faure, J P; Khiami, F; Vendeuvre, T

    2017-12-01

    Purpose and hypothesis: Patellar ligament rupture is a rare disabling pathology requiring a surgical ligament suture protected by a frame. The gold standard is the steel cable, but its rigidity and the necessity of a surgical re-intervention for its removal render it unsatisfactory. The objective of this paper is to quantify the mechanical protection provided by the terylene® in comparison with steel. Twenty-four knees of 12 fresh frozen cadaveric subjects were divided into 2 homogeneous groups (terylene and steel) of 12 knees (mean age = 69.3 years). Proximal ligament repair was performed according to a three-tunnel transosseous reinsertion technique. Mechanical tests were performed in flexion to simulate movement of the knee. The interligament gap and the amplitude angulation of the knee were measured by a system of extensometer and optical goniometer. Mechanical analysis permitted calculation of flexion amplitude for a ligament gap of 1 and 2 mm taking as initial angle the adjusting angle of pretension of the protection frame. Study of deformations of frames was performed. Statistical analysis was performed with a Wilcoxon Mann Whitney test. There is no significant difference in protection of the ligament suture between the "terylene" and "steel" groups. Mean flexion amplitudes (mΔF) show no significant differences between the 2 groups for a distension of the suture of 1 mm (m ΔF terylene1 = 4.74 °; mΔF steel1 = 5.91°; p = 0.198) and 2 mm (mΔF terylene2 = 8.71°; mΔF steel2 = 10.41°; p = 0.114). Elastic deformation of terylene was significantly greater than that of steel (p = 0.0004). Suture protection of the patellar ligament by a terylene wire is not significantly different from that provided by steel frame. The elastic properties of terylene and absence of a need for re intervention to secure its removal lead us towards its use in acute ruptures of the patellar ligament. The main limits involve the properties of

  6. Composition of the spheroidal objects in KhN77TYuR-VD alloy

    International Nuclear Information System (INIS)

    Kotkis, M.A.; Nabutovskii, L.S.; Ostrov, A.E.; Zil'berman, A.G.

    1986-01-01

    The authors make an element analysis of the spheroidal objects in KhN77TYuR-VD alloy with the use of the energy dispersion microanalyzer with which the Stereoscan S-180 scanning electron microscope is equipped. Examples of the qualitative element analysis are shown. The results of the investigations show that the composition of the spheroidal inclusions includes nickel, chromium, titanium, iron, and also silicon and sulfur. The information obtained makes it possible to make an assumption on the mechanism of origin of these objects

  7. General and localized corrosion of carbon and low-alloy steels in oxygenated high-temperature water. Final report

    International Nuclear Information System (INIS)

    Macdonald, D.D.; Smialowska, S.; Pednekar, S.

    1983-02-01

    The susceptibilities to stress corrosion cracking (SCC) of two carbon steels, SA106-grB and SA333-gr6, which are used in seamless BWR piping, and a low-alloy pressure vessel steel, A508-C12, were studied in high purity water as a function of oxygen concentration (0.16 to 8 ppM) and temperature (50 to 288 0 C) . The susceptibility to SCC was measured using the slow strain rate technique. The fracture surfaces of the test specimens were also examined using SEM to determine the mode of failure. In water containing 1 and 8 ppM oxygen and at temperatures above 135 0 C, transgranular stress corrosion cracking (TGSCC) was observed to occur in A508-C12, SA333-gr6 and SA106grB steels at very high stresses. The susceptibility to SCC increased with temperature

  8. Experimental verification of lifetime of bolting joints for WWER reactor pressure vessels

    International Nuclear Information System (INIS)

    Brumovsky, M.; Polachova, H.

    1992-01-01

    This paper presents results from experimental verification of cyclic lifetime of bolting joints of M 140x6 mm type used for WWER-440 MW reactor pressure vessels. Bolting joints or real dimensions were tested in a special testing equipment ZS 1000 in Skoda Concern. Stud bolts are made from 25Kh1MF or 38KhN3MFA type of steels. Tests were carried out at operating as well as at room temperatures with coefficient of asymmetry equal to 0.1; one tests was realized with given bending moment. Experimental results have been compared with calculated lifetimes according to ASME, Soviet and CMEA Codes. In all cases calculations give conservative assessments. (orig.)

  9. Effects of laser power during laser assisted cold spraying of Al-12wt%Si on stainless steel

    CSIR Research Space (South Africa)

    Tlotleng, Monnamme

    2012-10-01

    Full Text Available as they help improve the integrity of coatings1. Tissue engineering is one application under which metal coatings can undergo corrosion and wear. The results are not desirable given the amount of toxicity associated with them. In tissue engineering...W. Porosity values are (a) 2.64%, (b) 0.16% and (c) 4.12%. ? We have successfully deposited Al-12wt%Si on stainless steel substrate; ? Laser power has significant impact on the adhesion properties of power particles on metals as well as the coating...

  10. Mechanical Performance of Ferritic Martensitic Steels for High Dose Applications in Advanced Nuclear Reactors

    Science.gov (United States)

    Anderoglu, Osman; Byun, Thak Sang; Toloczko, Mychailo; Maloy, Stuart A.

    2013-01-01

    Ferritic/martensitic (F/M) steels are considered for core applications and pressure vessels in Generation IV reactors as well as first walls and blankets for fusion reactors. There are significant scientific data on testing and industrial experience in making this class of alloys worldwide. This experience makes F/M steels an attractive candidate. In this article, tensile behavior, fracture toughness and impact property, and creep behavior of the F/M steels under neutron irradiations to high doses with a focus on high Cr content (8 to 12) are reviewed. Tensile properties are very sensitive to irradiation temperature. Increase in yield and tensile strength (hardening) is accompanied with a loss of ductility and starts at very low doses under irradiation. The degradation of mechanical properties is most pronounced at martensitic steels exhibit a high fracture toughness after irradiation at all temperatures even below 673 K (400 °C), except when tested at room temperature after irradiations below 673 K (400 °C), which shows a significant reduction in fracture toughness. Creep studies showed that for the range of expected stresses in a reactor environment, the stress exponent is expected to be approximately one and the steady state creep rate in the absence of swelling is usually better than austenitic stainless steels both in terms of the creep rate and the temperature sensitivity of creep. In short, F/M steels show excellent promise for high dose applications in nuclear reactors.

  11. Recrystallization and modification of the stainless-steel surface relief under photonic heat load in powerful plasma discharges

    Energy Technology Data Exchange (ETDEWEB)

    Budaev, V. P., E-mail: budaev@mail.ru; Martynenko, Yu. V. [National Research Centre Kurchatov Institute (Russian Federation); Khimchenko, L. N. [Project Center ITER (Russian Federation); Zhitlukhin, A. M.; Klimov, N. S. [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Pitts, R. A. [ITER Organization (France); Linke, J. [EURATOM Association, Forschungszentrum Jülich GmbH (Germany); Bazylev, B. [IHM, Karlsruhe Institute of Technology (Germany); Belova, N. E.; Karpov, A. V. [National Research Centre Kurchatov Institute (Russian Federation); Kovalenko, D. V.; Podkovyrov, V. L.; Yaroshevskaya, A. D. [Troitsk Institute for Innovation and Fusion Research (Russian Federation)

    2013-11-15

    Targets made of ITER-grade 316L(N)-IG stainless steel and Russian-grade 12Cr18Ni10Ti stainless steel with a close composition were exposed at the QSPA-T plasma gun to plasma photonic radiation pulses simulating conditions of disruption mitigation in ITER. After a large number of pulses, modification of the stainless-steel surface was observed, such as the formation of a wavy structure, irregular roughness, and cracks on the target surface. X-ray and optic microscopic analyses of targets revealed changes in the orientation and dimensions of crystallites (grains) over a depth of up to 20 μm for 316L(N)-IG stainless steel after 200 pulses and up to 40 μm for 12Cr18Ni10Ti stainless steel after 50 pulses, which is significantly larger than the depth of the layer melted in one pulse (∼10 μm). In a series of 200 tests of ITER-grade 316L(N)-IG ITER stainless steel, a linear increase in the height of irregularity (roughness) with increasing number of pulses at a rate of up to ∼1 μm per pulse was observed. No alteration in the chemical composition of the stainless-steel surface in the series of tests was revealed. A model is developed that describes the formation of wavy irregularities on the melted metal surface with allowance for the nonlinear stage of instability of the melted layer with a vapor/plasma flow above it. A decisive factor in this case is the viscous flow of the melted metal from the troughs to tops of the wavy structure. The model predicts saturation of the growth of the wavy structure when its amplitude becomes comparable with its wavelength. Approaches to describing the observed stochastic relief and roughness of the stainless-steel surface formed in the series of tests are considered. The recurrence of the melting-solidification process in which mechanisms of the hill growth compete with the spreading of the material from the hills can result in the formation of a stochastic relief.

  12. Microstructural evolution at the overlap zones of 12Cr martensitic stainless steel laser alloyed with TiC

    CSIR Research Space (South Africa)

    Adebiyi, DI

    2014-09-01

    Full Text Available are not obtainable in the single tracks. X12CrNiMo steel has been laser alloyed with TiC using a 4.4 kW continuous wave (CW) Nd:YAG laser. The process parameters were first optimised after which they were kept constant for overlap ratios of 50% and 75%. The depths...

  13. Study of radiation-thermal effect of electron beam on steel and cast iron

    International Nuclear Information System (INIS)

    Machurin, E.S.; Lonchin, G.M.

    1980-01-01

    Studied is the influence of radiation-heat treatment by high energy (3-4.5 MeV) electron beam on the structure and properties of carbon steels (65G, 90KhF) and cast iron. Metallography and electron microscopy methods are used to study microstructure. It is shown that after the treatment by the electron beam there is observed noticeable structure grinding, sample fracture viscosity (even in a quenched state), increase of hardness and impact strength. The mechanism of metal heating process by electron beam is calculated and temperature field is defined in a heating region accounting for electron beam characteristics, medium and geometric factor. Theoretical data are close to experimental ones obtained in a course of determining the microhardness of irradiated samples for the cases of electron treatment duration up to 10 s

  14. Accumulation of radioactive corrosion products on steel surfaces of VVER type nuclear reactors. I. 110mAg

    CSIR Research Space (South Africa)

    Hirschberg, G

    1999-03-01

    Full Text Available contaminants in the passive layer formed on austenitic stainless steel. In the first part of the series the accumulation of 110mAg has been investigated. Potential dependent sorption of Ag+. ions (cementation) is found to be the predominant process...

  15. Water corrosion test of oxide dispersion strengthened (ODS) steel claddings

    International Nuclear Information System (INIS)

    Narita, Takeshi; Ukai, Shigeharu; Kaito, Takeji; Ohtsuka, Satoshi; Matsuda, Yasushi

    2006-07-01

    As a part of feasibility study of ODS steel cladding, its water corrosion resistance was examined under water pool condition. Although addition of Cr is effective for preventing water corrosion, excessive Cr addition leads to embrittlement due to the Cr-rich α' precipitate formation. In the ODS steel developed by the Japan Atomic Energy Agency (JAEA), the Cr content is controlled in 9Cr-ODS martensite and 12Cr-ODS ferrite. In this study, water corrosion test was conducted for these ODS steels, and their results were compared with that of conventional austenitic stainless steel and ferritic-martensitic stainless steel. Following results were obtained in this study. (1) Corrosion rate of 9Cr-ODS martensitic and 12Cr-ODS ferritic steel are significantly small and no pitting was observed. Thus, these ODS steels have superior resistance for water corrosion under the condition of 60degC and pH8-12. (2) It was showed that 9Cr-ODS martensitic steel and 12Cr-ODS ferritic steel have comparable water corrosion resistance to that of PNC316 and PNC-FMS at 60degC for 1,000h under varying pH of 8, 10. Water corrosion resistance of these alloys is slightly larger than that of PNC316 and PNC-FMS at pH12 without significant difference of appearance and uneven condition. (author)

  16. Deformability of 12MKh steel within the temperature range of polymorphous transformations

    International Nuclear Information System (INIS)

    Surovtsev, A.P.; Sukhanov, V.E.

    1987-01-01

    Deformability and the structure of 12 MKh steel under tension, upsetting and torsion within the temperature range of polymorphous transformations have been investigated. Tests for tension showed the presence of two plasticity maxima, which correspond to the temperatures of P-A and F-A structural transformation beginning. Loss of strength during deformation is connected with dynamic polygonization and the initial stage of dynamic recrystallization as well as the state preceding ferrite transformation. Loss of plasticity is observed at the temperature accompanying the end of F-A transformation; it is explained by the formation of more strength martensite and by increase of material porosity as a result of the transformation with volume decrease

  17. Deformability of 12MKh steel within the temperature range of polymorphous transformations

    Energy Technology Data Exchange (ETDEWEB)

    Surovtsev, A P; Sukhanov, V E

    1987-01-01

    Deformability and the structure of 12 MKh steel under tension, upsetting and torsion within the temperature range of polymorphous transformations have been investigated. Tests for tension showed the presence of two plasticity maxima, which correspond to the temperatures of P-A and F-A structural transformation beginning. Loss of strength during deformation is connected with dynamic polygonization and the initial stage of dynamic recrystallization as well as the state preceding ferrite transformation. Loss of plasticity is observed at the temperature accompanying the end of F-A transformation; it is explained by the formation of more strength martensite and by increase of material porosity as a result of the transformation with volume decrease.

  18. Environmental Fatigue Behaviors of CF8M Stainless Steel in 310 .deg. C Deoxygenated Water - Effects of Hydrogen and Microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hun; Cho, Pyungyeon; Jang, Changheui [KAIST, Daejeon (Korea, Republic of); Kim, Tae Soon [Korea Hydro and Nuclear Power Corporation, Seoul (Korea, Republic of)

    2014-01-15

    The effects of environment and microstructure on low cycle fatigue (LCF) behaviors of CF8M stainless steels containing 11% of ferrites were investigated in a 310 .deg. C deoxygenated water environment. The reduction of LCF life of CF8M in a 310 .deg. C deoxygenated water was smaller than 316LN stainless steels. Based on the microstructure and fatigue surface analyses, it was confirmed that the hydrogen induced cracking contributed to the reduction in LCF life for CF8M as well as for 316LN. However, many secondary cracks were found on the boundaries of ferrite phases in CF8M, which effectively reduced the stress concentration at the crack tip. Because of the reduced stress concentration, the accelerated fatigue crack growth by hydrogen induced cracking was less significant, which resulted in the smaller environmental effects for CF8M than 316LN in a 310 .deg. C deoxygenated water.

  19. The carbide M7C3 in low-temperature-carburized austenitic stainless steel

    International Nuclear Information System (INIS)

    Ernst, Frank; Li, Dingqiang; Kahn, Harold; Michal, Gary M.; Heuer, Arthur H.

    2011-01-01

    Prolonged low-temperature gas-phase carburization of AISI 316L-type austenitic stainless steel can cause intragranular precipitation of the carbide M 7 C 3 (M: randomly dispersed Fe, Cr, Ni). Transmission electron microscopy revealed that the carbide particles have the shape of needles. They grow by a ledge-migration mechanism and in a crystallographic orientation relationship to the austenite matrix that enables highly coherent interphase interfaces. A small solubility limit of Ni in the carbide and restricted Ni diffusivity at the processing temperature leads to Ni pileup around the particles and may explain the extreme aspect ratio of the particle shape. These characteristics closely resemble what has been observed earlier for precipitates of M 5 C 2 under slightly different processing conditions and can be rationalized by considering the particular constraints imposed by carburization at low temperature.

  20. Technical Note: Calibration device for the krypton hygrometer KH20

    Directory of Open Access Journals (Sweden)

    T. Foken

    2012-08-01

    Full Text Available A calibration device for krypton hygrometers (KH20, Campbell Scientific, Inc. with variable path length is presented. This unit allows for in-situ calibrations of the krypton hygrometer, which is typically not very stable over time, during measuring campaigns. It was constructed mainly for application at high altitudes and low temperatures, where further improvements are needed to the IR-hygrometers which are normally used. The changing path length requires that a changing concentration of the absorber be simulated. Because oxygen absorbs more strongly than water vapour, the calibration is made against oxygen and transferred to water vapour. The design of the calibration instrument is made as one unit containing a stepper motor system, PC and humidity sensor. For the calibration, it is necessary to install the krypton hygrometer on this unit.