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.

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.

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

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

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

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

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%

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

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

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.

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.

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.

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

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

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.

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.)

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

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

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

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

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

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

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

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.

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

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.

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

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.

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

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.

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

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

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

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

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.

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

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

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

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

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

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.

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

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

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

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

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

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

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

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

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

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.

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

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

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

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

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

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

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

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.

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

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.

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

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

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

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.

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)

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.

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)

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

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

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

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

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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Synthesis, Crystal Structure, and Nonlinear Optical Properties of a New Alkali and Alkaline Earth Metal Carbonate RbNa5Ca5(CO38

Directory of Open Access Journals (Sweden)

Qiaoling Chen

2016-12-01

Full Text Available A new nonlinear optical (NLO material, RbNa5Ca5(CO38, has been synthesized by the hydrothermal method. The crystal structure is established by single-crystal X-ray diffraction. RbNa5Ca5(CO38 crystallizes in the hexagonal crystal system with space group P63mc (No. 186. The structure of RbNa5Ca5(CO38 can be described as the adjacent infinite [CaCO3]∞ layers lying in the a-b plane bridged through standing-on-edge [CO3] groups by sharing O atoms (two-fold coordinated to build a framework with four types of tunnels running through the b-axis. The Rb, Na, and [Na0.67Ca0.33] atoms reside in these tunnels, respectively. The measurement of second harmonic generation (SHG indicated that RbNa5Ca5(CO38 is a phase-matchable material, which had SHG responses of approximately 1×KH2PO4 (KDP. Meanwhile, the results from the UV-VIS diffuse reflectance spectroscopy study of the powder samples indicated that the UV cut-off edges of RbNa5Ca5(CO38 is about 203 nm.

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

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

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

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

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

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

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

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

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.

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

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

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

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

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

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.

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)

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

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

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

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

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.

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.

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

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

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

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.

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

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

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.)

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

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

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

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

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

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

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

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

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

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

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

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.

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

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

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

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

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

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.)

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

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.

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.

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%

Influence of Healing Period Upon Bone Turn Over on Maxillary Sinus Floor Augmentation Grafted Solely with Deproteinized Bovine Bone Mineral: A Prospective Human Histological and Clinical Trial.

Science.gov (United States)

Wang, Feng; Zhou, Wenjie; Monje, Alberto; Huang, Wei; Wang, Yueping; Wu, Yiqun

2017-04-01

To investigate the influence of maturation timing upon histological, histomorphometric and clinical outcomes when deproteinized bovine bone mineral (DBBM) was used as a sole biomaterial for staged maxillary sinus floor augmentation (MSFA). Patients with a posterior edentulous maxillary situation and a vertical bone height ≤ 4 mm were included in this study. A staged MSFA was carried out. After MSFA with DBBM as a sole grafting material, biopsy cores were harvested with simultaneous implant placement followed by a healing period of 5, 8, and 11 months, respectively. Micro-CT, histologic and histomorphometric analyses were performed. Forty-one patients were enrolled and 38 bone core biopsies were harvested. Significantly greater BV/TV was observed between 5- and 8-month healing from micro-CT analysis. Histomorphometric analyses showed the ratio of mineralized newly formed bone increased slightly from 5 to 11 months; however, no statistically significant difference was reached (p = .409). Residual bone substitute decreased from 37.3 ± 5.04% to 20.6 ± 7.45%, achieving a statistical significant difference from of 5 up to 11 months (p < .01). Moreover, no implant failure, biological or technical complication occurred after 12-month follow-up of functional loading. DBBM utilized as sole grafting material in staged MSFA demonstrated to be clinically effective regardless of the healing period. Histomorphometrical and micro-CT assessments revealed that at later stages of healing (8 and 11 months) there is a higher proportion of newly-bone formation compared to earlier stages (5 months). Moreover, the longer the maturation period, the substantially lesser remaining biomaterial could be expected. Even though, these facts did not seem to negatively impact on the implant prognosis 1-year after loading. © 2016 Wiley Periodicals, Inc.

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

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)

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

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

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

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.

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

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

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

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

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

Electrochemical and quantum chemical studies of some indole derivatives as corrosion inhibitors for C38 steel in molar hydrochloric acid

International Nuclear Information System (INIS)

Lebrini, M.; Robert, F.; Vezin, H.; Roos, C.

2010-01-01

A comparative study of 9H-pyrido[3,4-b]indole (norharmane) and 1-methyl-9H-pyrido[3,4-b]indole (harmane) as inhibitors for C38 steel corrosion in 1 M HCl solution at 25 o C was carried out. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were applied to study the metal corrosion behavior in the absence and presence of different concentrations of these inhibitors. The OCP as a function of time were also established. Cathodic and anodic polarization curves show that norharmane and harmane are a mixed-type inhibitors. Adsorption of indole derivatives on the C38 steel surface, in 1 M HCl solution, follows the Langmuir adsorption isotherm model. The ΔG ads o values were calculated and discussed. The potential of zero charge (PZC) of the C38 steel in inhibited solution was studied by the EIS method, and a mechanism for the adsorption process was proposed. Raman spectroscopy confirmed that indole molecules strongly adsorbed onto the steel surface. The electronic properties of indole derivates, obtained using the AM1 semi-empirical quantum chemical approach, were correlated with their experimental efficiencies using the linear resistance model (LR).

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

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)

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

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

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.

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

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

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.

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)

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

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

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

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

27 CFR 5.38 - Net contents.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Net contents. 5.38 Section 5.38 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS LABELING AND ADVERTISING OF DISTILLED SPIRITS Labeling Requirements for Distilled...

[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.

Cancer incidence among mild steel and stainless steel welders and other metal workers

DEFF Research Database (Denmark)

Hansen, K S; Lauritsen, J M; Skytthe, A

1996-01-01

by a postal questionnaire in living cohort members and interviews by proxy for deceased and emigrated subjects. The incidence of lung cancer was increased among workers ever "employed as welders" (SIR = 1.38, 95% C.I. 1.03-1.81). There was a significant excess risk of lung cancer among "mild steel (MS) only...... "stainless steel (SS) only welders" (SIR = 2.38, 95% C.I. 0.77-5.55). In spite of signs of inconsistency in the risk estimation by duration and latency, we find the results support the conclusions of other studies: employment as a welder is associated with an increased lung cancer risk....

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

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

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

Study of Temperature Effect on the Corrosion Inhibition of C38 Carbon Steel Using Amino-tris(Methylenephosphonic Acid in Hydrochloric Acid Solution

Directory of Open Access Journals (Sweden)

Najoua Labjar

2011-01-01

Full Text Available Tafel polarization method was used to assess the corrosion inhibitive and adsorption behaviours of amino-tris(methylenephosphonic acid (ATMP for C38 carbon steel in 1 M HCl solution in the temperature range from 30 to 60∘C. It was shown that the corrosion inhibition efficiency was found to increase with increase in ATMP concentration but decreased with temperature, which is suggestive of physical adsorption mechanism. The adsorption of the ATMP onto the C38 steel surface was found to follow Langmuir adsorption isotherm model. The corrosion inhibition mechanism was further corroborated by the values of kinetic and thermodynamic parameters obtained from the experimental data.

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.

Combined effect of rapid nitriding and plastic deformation on the surface strength, toughness and wear resistance of steel 38CrMoAlA

DEFF Research Database (Denmark)

Wang, B.; Lv, Z.A.; Zhou, Z.A.

2015-01-01

The combined treatment of pressurized gas nitriding and cold rolling is proposed as a new approach to rapid preparation of a strong and tough nitrided layer for steel 38CrMoAlA. The microstructural characteristics and properties of the modified surface layer in comparison with those of the conven......The combined treatment of pressurized gas nitriding and cold rolling is proposed as a new approach to rapid preparation of a strong and tough nitrided layer for steel 38CrMoAlA. The microstructural characteristics and properties of the modified surface layer in comparison with those...

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

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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

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

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

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.

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

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...

38 CFR 60.5 - Travel.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Travel. 60.5 Section 60.5... TEMPORARY LODGING § 60.5 Travel. As a condition for receiving temporary lodging under this part, a veteran must be required to travel either 50 or more miles, or at least two hours from his or her home to the...

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%

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

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

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.

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)

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

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

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

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

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

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.

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.

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

Draft genome sequence of Bacillus okhensis Kh10-101T, a halo-alkali tolerant bacterium from Indian saltpan

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Pilla Sankara Krishna

2015-12-01

Full Text Available We report the 4.86-Mb draft genome sequence of Bacillus okhensis strain Kh10-101T, a halo-alkali tolerant rod shaped bacterium isolated from a salt pan near port of Okha, India. This bacterium is a potential model to study the molecular response of bacteria to salt as well as alkaline stress, as it thrives under both high salt and high pH conditions. The draft genome consist of 4,865,284 bp with 38.2% G + C, 4952 predicted CDS, 157 tRNAs and 8 rRNAs. Sequence was deposited at DDBJ/EMBL/GenBank under the project accession JRJU00000000.

Welding of heat-resistant 20% Cr-5% Al steels

International Nuclear Information System (INIS)

Tusek, J.; Arbi, D.; Kosmac, A.; Nartnik, U.

2002-01-01

The paper treats welding of heat-resistant ferritic stainless steels alloyed with approximately 20% Cr and 5% Al. The major part of the paper is dedicated to welding of 20% Cr-5% Al steel with 3 mm in thickness. Welding was carried out with five different welding processes, i. e., manual metal-arc, MIG, TIG, plasma arc, and laser beam welding processes, using a filler material and using no filler material, respectively. The welded joints obtained were subjected to mechanical tests and the analysis of microstructure in the weld metal and the transition zone. The investigations conducted showed that heat-resistant ferritic stainless 20% Cr-5% Al steel can be welded with fusion welding processes using a Ni-based filler material. (orig.)

Microstructural characterization of 5-9% chromium reduced-activation steels

International Nuclear Information System (INIS)

Jayaram, R.; Klueh, R.L.

1997-01-01

The microstructures of a 9Cr-2W-0.25-0.1C (9Cr-2WV), a 9Cr-2W-0.25V-0.07Ta-0.1C (9Cr-2WVTa), a 7Cr-2W-0.25V-0.07Ta-0.1C (7Cr-2WVTa), and a 5Cr-2W-0.25V-0.07Ta-0.1C (5Cr-2WVTa) steel (all compositions are in weight percent) have been characterized by Analytical Electron Microscopy (AEM) and Atom Probe Field Ion Microscopy (APFIM). The matrix in all four reduced-activation steels was 100% martensite. In the two 9Cr steels, the stable precipitates were blocky M 23 C 6 and small spherical MC. The two lower-chromium steels contained blocky M 7 C 3 and small needle-shaped carbonitrides in addition to M 23 C 6 . AEM and APFIM analysis revealed that in the steels containing tantalum, the majority of the tantalum was in solid solution. The experimental observations were in good agreement with phases and compositions predicted by phase equilibria calculations

Peculiar features in formation of diffusion layer properties during nitridation

International Nuclear Information System (INIS)

Gulyaev, A.P.; Konoval'tsev, V.I.; Nikitin, V.V.

1983-01-01

Peculiarities of the formation of multiphase nitridated layer at samples of commercial iron, 20, 40Kh and 38KhMYu6A steels are studied with the help of high-temperature methods of investigation (X-ray diffraction analysis, hardening and thickness measuring). It is found out that during the saturation the solid solution oversaturated with nitrogen is formed; some increase in hardness in the process is a result of solid solution hardening and the increase of thickness of nitride zone; however the main growth of the layer hardness is achieved during the cooling as a result of α phase precipitating hardening

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

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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.

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

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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 

[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.

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.)

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...

Microstructural analysis of hot press formed 22MnB5 steel

Science.gov (United States)

Aziz, Nuraini; Aqida, Syarifah Nur; Ismail, Izwan

2017-10-01

This paper presents a microstructural study on hot press formed 22MnB5 steel for enhanced mechanical properties. Hot press forming process consists of simultaneous forming and quenching of heated blank. The 22MnB5 steel was processed at three different parameter settings: quenching time, water temperature and water flow rate. 22MnB5 was processed using 33 full factorial design of experiment (DOE). The full factorial DOE was designed using three factors of quenching time, water temperature and water flow rate at three levels. The factors level were quenching time range of 5 - 11 s, water temperature; 5 - 27°C and water flow rate; 20 - 40 L/min. The as-received and hot press forming processed steel was characterised for metallographic study and martensitic structure area percentage using JEOL Field Emission Scanning Electron Microscopic (FESEM). From the experimental finding, the hot press formed 22MnB5 steel consisted of 50 to 84% martensitic structure area. The minimum quenching time of 8 seconds was required to obtain formed sample with high percentage of martensite. These findings contribute to initial design of processing parameters in hot press forming of 22MnB5 steel blanks for automotive component.

Microstructural characterization of 5-9% chromium reduced-activation steels

Energy Technology Data Exchange (ETDEWEB)

Jayaram, R. [Univ. of Pittsburgh, PA (United States); Klueh, R.L. [Oak Ridge National Lab., TN (United States)

1997-08-01

The microstructures of a 9Cr-2W-0.25-0.1C (9Cr-2WV), a 9Cr-2W-0.25V-0.07Ta-0.1C (9Cr-2WVTa), a 7Cr-2W-0.25V-0.07Ta-0.1C (7Cr-2WVTa), and a 5Cr-2W-0.25V-0.07Ta-0.1C (5Cr-2WVTa) steel (all compositions are in weight percent) have been characterized by Analytical Electron Microscopy (AEM) and Atom Probe Field Ion Microscopy (APFIM). The matrix in all four reduced-activation steels was 100% martensite. In the two 9Cr steels, the stable precipitates were blocky M{sub 23}C{sub 6} and small spherical MC. The two lower-chromium steels contained blocky M{sub 7}C{sub 3} and small needle-shaped carbonitrides in addition to M{sub 23}C{sub 6}. AEM and APFIM analysis revealed that in the steels containing tantalum, the majority of the tantalum was in solid solution. The experimental observations were in good agreement with phases and compositions predicted by phase equilibria calculations.

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.

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

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.)

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

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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.

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

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

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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.

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

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

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

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

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

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

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

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

The kinetics of phase transformations of undercooled austenite of the 38MnCrNi6-4-4 hypoeutectoid steel

OpenAIRE

R. Dąbrowski; R. Dziurka; E. Rożniata

2012-01-01

Purpose: Present work corresponds to the research on the kinetic of phase transformation of undercooled austenite of 38MnCrNi6-4-4 hypoeutctoid steel. The kinetic of phase transformation of under cooled austenite of investigated alloy was presented on CCT diagram (continuous cooling transformation). Also the methodology of a dilatometric samples preparation and the method of the critical points determination were described.Design/methodology/approach: The austenitising temperature was defined...

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.

Shrinkage Porosity Criterion and Its Application to A 5.5 Ton Steel Ingot

Directory of Open Access Journals (Sweden)

Zhang C.

2016-06-01

Full Text Available In order to predict the distribution of shrinkage porosity in steel ingot efficiently and accurately, a criterion R√L and a method to obtain its threshold value were proposed. The criterion R√L was derived based on the solidification characteristics of steel ingot and pressure gradient in the mushy zone, in which the physical properties, the thermal parameters, the structure of the mushy zone and the secondary dendrite arm spacing were all taken into consideration. The threshold value of the criterion R√L was obtained with combination of numerical simulation of ingot solidification and total solidification shrinkage rate. Prediction of the shrinkage porosity in a 5.5 ton ingot of 2Cr13 steel with criterion R√L>0.21 m · °C1/2 · s−3/2 agreed well with the results of experimental sectioning. Based on this criterion, optimization of the ingot was carried out by decreasing the height-to-diameter ratio and increasing the taper, which successfully eliminated the centreline porosity and further proved the applicability of this criterion.

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

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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

Specific Features of Structural-Phase State and Properties of Reactor Pressure Vessel Steel at Elevated Irradiation Temperature

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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.

A luminary of tatar archaeology. To the 85th anniversary of the birth of A.Kh. Khalikov

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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.

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.)

Stress corrosion cracking properties of 15-5PH steel

Science.gov (United States)

Rosa, Ferdinand

1993-01-01

Unexpected occurrence of failures, due to stress corrosion cracking (SCC) of structural components, indicate a need for improved characterization of materials and more advanced analytical procedures for reliably predicting structures performance. Accordingly, the purpose of this study was to determine the stress corrosion susceptibility of 15-5PH steel over a wide range of applied strain rates in a highly corrosive environment. The selected environment for this investigation was a highly acidified sodium chloride (NaCl) aqueous solution. The selected alloy for the study was a 15-5PH steel in the H900 condition. The slow strain rate technique was selected to test the metals specimens.

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

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

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

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....

Multiaxial creep of fine grained 0.5Cr-0.5Mo-0.25V and coarse grained 1Cr-0.5Mo steels

International Nuclear Information System (INIS)

Browne, R.J.; Flewitt, P.E.J.; Lonsdale, D.

1991-01-01

To explore the multiaxial creep response of materials used for electrical power generating plant, two steels, a fine grained 0.5Cr-0.5Mo-0.25V steel in a normalised and tempered condition with high creep ductility and a coarse grained 1Cr-0.5Mo steel in a quenched and tempered condition with low uniaxial creep ductility, have been selected. A range of multiaxial stress testing techniques which span the stress states that would allow identification of any technique dependent variables has been used. The deformation and failure of the normalised and tempered 0.5Cr-0.5Mo-0.25V steel for a range of multiaxial test techniques and, therefore, stress states may be described by an equivalent stress criterion. The results from the multiaxial tests carried out on the fully bainitic 1Cr-0.5Mo steel show that the multiaxial stress rupture criterion (MSRC) varies with stress state; at high triaxiality (notch), it is controlled by the maximum principal stress, whereas at low triaxiality (shear) it is dependent on both maximum principal stress and equivalent stress. Furthermore, a simple description of stress state based on maximum principal and equivalent stress does not define this uniquely, since the MSRC derived from uniaxial and torsion testing does not describe the failure of notch, tube, or double shear tests. (author)

Study of nitrogen solubility in multicomponent iron alloys at its pressure in gaseous phase up to 1000kPa

International Nuclear Information System (INIS)

Pomarin, Yu.M.; Grigorenko, G.M.; Latash, Yu.V.; Kanibolotskij, S.A.

1983-01-01

A facility in which metal is melted in a weighed state and nitrogen partical pressure during relting may be charge from 0 to 1000 kPa is developed to investigate nitrogen solubility is liquim metals and alloys. Investigation of nitrogen solubility was performed using samples of 03Kh25N5AM3 steel and Kh20N5, Kh20N10, Kh40N10, Kh40N20 alloys. Positive deflection of [N]=f(√Psub(Nsub(2))) dependence from the Henry law is shown to be observed in the Kh40N10 alloy in the 100-1000 kPa pressure range. In this case the vatue of positive deflection decreases with temperature growth and at T=2273 K nitrogen solubility in the alloy submits to the law of square root. An equation permitting to calculate nitrogen solubility in alloys of Fe-Cr-Ni and Fe-Cr-Mn systems in the 0 to 1000 kPa range of nitrogen partial pressures is obtained

AERODYNAMIC IMPROVEMENT OF KhADI 33 RACING CAR RADIATOR COMPARTMENT

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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.

Observation of simultaneous increase in strength and ductility by grain refinement in a Fe-34.5Mn-0.04C steel

DEFF Research Database (Denmark)

Wang, Y. H.; Kang, J. M.; Peng, Y.

2017-01-01

Fine grained Fe-34.5Mn-0.04C steel samples with fully recrystallized grain sizes of 3.8 to 2.0 mu m were prepared by cold rolling followed by annealing a temperatures of either 650 degrees C or 800 degrees C. It is found that a simultaneous increase in both strength and ductility can be obtained ...... by grain refinement, leading to an observation that the best combination of strength and ductility occurs in the sample with the finest recrystallized grain size....

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

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

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...

Gas metal arc weldability of 1.5 GPa grade martensitic steels

Science.gov (United States)

Hwang, Insung; Yun, Hyeonsang; Kim, Dongcheol; Kang, Munjin; Kim, Young-Min

2018-01-01

The gas metal arc weldability of 1.5 GPa grade martensitic (MART) steel was evaluated using both inverter direct current (DC) and DC pulse power type welders, under conditions of different welding currents, welding speeds, and shielding gasses. By investigating the bead appearance, tensile strength, and arc stability, it was determined that DC pulse power is better than inverter DC power for arc welding of 1.3 mm thick 1.5 GPa grade MART steel. Further, from the results of the weldability for various shielding gases, it was determined that mixed shielding gas is more effective for welding 1.5 GPa grade MART steel than is pure inert gas (Ar) or active (CO2) gas. In the case of pure shielding gas, no sound bead was formed under any conditions. However, when the mixed shielding gas was used, sound and fine beads were obtained.

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

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

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

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

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.)

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%

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.

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.

Sources of optical distortion in rapidly grown crystals of KH2PO4

International Nuclear Information System (INIS)

De Yoreo, J.J.; Zaitseva, N.P.; Woods, B.W.; Land, T.A.; Rek, Z.U.

1995-01-01

We report results of x-ray topographic and optical measurements on KH 2 PO 4 crystals grown at rates of 5 to 30mm/day. We show that optical distortion in these crystals is caused primarily by 3 sources: dislocations, differences in composition between adjacent growth sectors of the crystal, and differences in composition between adjacent sectors of vicinal growth hillocks within a single growth sector of the crystal. We find that the compositional heterogeneities cause spatial variations in the refractive index and induced distortion of the transmitted wave front while large groups of dislocations are responsible for strain induced birefringence which leads to beam depolarization

Hepatocyte cytoskeleton during ischemia and reperfusion influence of ANP-mediated p38 MAPK activation

Institute of Scientific and Technical Information of China (English)

Melanie Keller; Alexander L Gerbes; Stefanie Kulhanek-Heinze; Tobias Gerwig; Uwe Grützner; Nico van Rooijen; Angelika M Vollmar; Alexandra K Kiemer

2005-01-01

AIM: To determine functional consequences of this activation, whereby we focused on a potential regulation of the hepatocyte cytoskeleton during ischemia and reperfusion.METHODS: For in vivo experiments, animals received ANP (5 μg/kg) intravenously. In a different experimental setting, isolated rat livers were perfused with KH-buffer ±ANP (200 nmol/L)±SB203580 (2 μmol/L). Liverswere then kept under ischemic conditions for 24 h, and either transplanted or reperfused. Actin, Hsp27, and phosphorylated Hsp27 were determined by Western blotting, p38 MAPK activity by in vitro phosphorylation assay. F-actin distribution was determined by confocal microscopy.RESULTS: We first confirmed that ANP preconditioning leads to an activation of p38 MAPK and observedalterations of the cytoskeleton in hepatocytes of ANPpreconditioned organs. ANP induced an increase of hepatic F-actin after ischemia, which could be prevented by the p38 MAPK inhibitor SB203580 but had no effect on bile flow. After ischemia untreated livers showed a translocation of Hsp27 towards the cytoskeleton and an increase in total Hsp27, whereas ANP preconditioning prohibited translocation but caused an augmentation of Hsp27 phosphorylation. This effect is also mediated via p38 MAPK, since it was abrogated by the p38 MAPK inhibitor SB203580.CONCLUSION: This study reveals that ANP-mediated p38 MAPK activation leads to changes in hepatocyte cytoskeleton involving an elevation of phosphorylated Hsp27 and thereby for the first time shows functional consequences of ANP-induced hepatic p38 MAPK activation.

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.

Laser Welding of Coated Press-hardened Steel 22MnB5

Science.gov (United States)

Siltanen, Jukka; Minkkinen, Ari; Järn, Sanna

The press-hardening process is widely used for steels that are used in the automotive industry. Using ultra-high-strength steels enables car manufacturers to build lighter, stronger, and safer vehicles at a reduced cost and generating lower CO2 emissions. In the study, laser welding properties of the coated hot stamped steel 22BMn5 were studied. A constant 900 °C temperature was used to heat the steel plates, and two different furnace times were used in the press-hardening, being 300 and 740 seconds. Some of the plates were shot blasted to see the influence of the partly removed oxide layer on the laser welding and quality. The welding set-up, welding, and testing of the weld specimens complied with the automotive testing code SEP 1220.

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

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

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

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...

G3.5 PAMAM dendrimers enhance transepithelial transport of SN38 while minimizing gastrointestinal toxicity.

Science.gov (United States)

Goldberg, Deborah S; Vijayalakshmi, Nirmalkumar; Swaan, Peter W; Ghandehari, Hamidreza

2011-03-30

Poly(amido amine) (PAMAM) dendrimers have shown promise in oral drug delivery. Conjugation of SN38 to PAMAM dendrimers has the potential to improve its oral absorption while minimizing gastrointestinal toxicity. In this work we evaluated G3.5 PAMAM dendrimer-SN38 conjugates with ester-linked glycine and β-alanine spacers for their suitability in oral therapy of hepatic colorectal cancer metastases. G3.5-βAlanine-SN38 was mostly stable while G3.5-Glycine-SN38 showed 10%, 20%, and 56% SN38 release in simulated gastric, intestinal and liver environments for up to 6, 24 and 48 hours, respectively. Short-term treatment of Caco-2 cells with G3.5-SN38 conjugates did not reduce cell viability, while comparable concentrations of SN38 caused significant cytotoxicity. G3.5-Glycine-SN38 and G3.5-βAlanine-SN38 showed IC₅₀ values of 0.60 and 3.59 μM, respectively, in HT-29 cells treated for 48 h, indicating the efficacy of the drug delivery system in colorectal cancer cells with longer incubation time. Both conjugates increased SN38 transepithelial transport compared to the free drug. Transport of G3.5-Glycine-SN38 was highly concentration-dependent whereas transport of G3.5-βAlanine-SN38 was concentration-independent, highlighting the influence of drug loading and spacer chemistry on transport mechanism. Together these results show that PAMAM dendrimers have the potential to improve the oral bioavailability of potent anti-cancer drugs. Copyright © 2010 Elsevier B.V. All rights reserved.

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

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

46 CFR 56.60-5 - Steel (High temperature applications).

Science.gov (United States)

2010-10-01

....A.) Upon prolonged exposure to temperatures above 775 °F (412 °C), the carbide phase of plain carbon steel, plain nickel-alloy steel, carbon-manganese-alloy steel, manganese-vanadium-alloy steel, and carbon-silicon steel may convert to graphite. (b) (Reproduces 124.2.B.) Upon prolonged exposure to...

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

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

Character evaluation of strength in dispersion strengthened ferritic steel. 5

International Nuclear Information System (INIS)

Yoshida, Fuyuki; Nakashima, Hideharu

1997-03-01

In order to clarify the high-temperature deformation behaviour and the origin of threshold stress of ODS martensite steel with Y 2 O 3 particles, the stress-strain curves were measured by compression test at 600 to 700degC and at strain rates from 2x10 -5 to 2x10 -3 s -1 , and the threshold stress was measured by stress abruptly loading test (SAL test) at 650degC. Further, the possibility of temperature dependence of threshold stress was discussed by estimating the activation energy for dislocations to detach the Y 2 O 3 particles. The results are summarized as follows. 1) The stress exponents of ODS martensite steel were 22-35. And the activation energy of high-temperature deformation was 742 kJ/mol. Those deformation behaviour of ODS martensite steel agrees with the deformation behaviour of ODS ferritic steel. 2) The Orowan stress and the void-hardening stress calculated from dispersion parameters approximately agreed with the threshold stress obtained by SAL test. It is concluded that the originating mechanism of the threshold stress in ODS martensite steel is the Srolovitz's one. 3) The calculated activation energy for a dislocation to detach the particles was very high compared to the thermal energy. Therefor, the threshold stress is almost independent of temperature. (author)

Effect of non-metallic inclusions on hydrogen-induced cracking of API5L X100 steel

Energy Technology Data Exchange (ETDEWEB)

Jin, T.Y.; Liu, Z.Y.; Cheng, Y.F. [Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Alberta (Canada)

2010-08-15

In this work, the type, composition and distribution of inclusions contained in an API5L X100 steel were characterized by scanning electron microscopy and energy-dispersive x-ray analysis. A hydrogen-charging at various current densities was used to introduce hydrogen into the steel, and the correlation between HIC and the inclusions was established. The microstructure of the steel consists of a leather-like bainitic ferrite matrix, with martensite/austenite as the second phase particles. At least four types of inclusions are contained in API5L X100 steel, elongated MnS inclusions and spherical Al-, Si- and Ca-Al-O-S-enriched inclusions. In particular, the majority of inclusions in the steel are Al-enriched. Upon hydrogen-charging, hydrogen blisters and HIC could be caused in the steel in the absence of external stress. The cracks are primarily associated with the Al- and Si-enriched inclusions, rather than the elongated MnS inclusion. The critical amount of hydrogen resulting in HIC of the tested API5L X100 steel is determined to be 3.24 ppm under condition in this work. (author)

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.

ac impedance, X-ray photoelectron spectroscopy and density functional theory studies of 3,5-bis(n-pyridyl)-1,2,4-oxadiazoles as efficient corrosion inhibitors for carbon steel surface in hydrochloric acid solution

Energy Technology Data Exchange (ETDEWEB)

Outirite, Moha; Lagrenee, Michel; Lebrini, Mounim [Unite de Catalyse et de Chimie du Solide, UMR-CNRS 8181, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Traisnel, Michel; Jama, Charafeddine [Laboratoire des Procedes d' Elaboration des Revetements Fonctionnels, PERF UMR-CNRS 8008, ENSCL, B.P. 90108, F-59652 Villeneuve d' Ascq Cedex (France); Vezin, Herve [Laboratoire de Chimie Organique et Macromoleculaire, UMR-CNRS 8009, USTL Bat C4, F-59655 Villeneuve d' Ascq Cedex (France); Bentiss, Fouad, E-mail: fbentiss@enscl.f [Laboratoire de Chimie de Coordination et d' Analytique, Faculte des Sciences, Universite Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco)

2010-02-01

The corrosion inhibition properties of a new class of oxadiazole derivatives, namely 3,5-bis(n-pyridyl)-1,2,4-oxadiazoles (n-DPOX) for C38 carbon steel corrosion in 1 M HCl medium were analysed by electrochemical impedance spectroscopy (EIS). An adequate structural model of the interface was used and the values of the corresponding parameters were calculated and discussed. The experimental results showed that these compounds are excellent inhibitors for the C38 steel corrosion in acid solution and that the protection efficiency increased with increasing the inhibitors concentration. Electrochemical impedance data demonstrate that the addition of the n-DPOX derivatives in the corrosive solution decreases the charge capacitance and simultaneously increases the function of the charge/discharge of the interface, facilitating the formation of an adsorbed layer over the steel surface. Adsorption of these inhibitors on the steel surface obeys to the Langmuir adsorption isotherm. X-ray photoelectron spectroscopy (XPS) and the thermodynamic data of adsorption showed that inhibition of steel corrosion in normal hydrochloric solution by n-DPOX is due to the formation of a chemisorbed film on the steel surface. Quantum chemical calculations using the Density Functional Theory (DFT) and the Quantitative Structure Activity Relationship (QSAR) approach were performed on n-DPOX derivatives to determine the relationship between molecular structure and their inhibition efficiencies. The results of the quantum chemical calculations and experimental inhibition efficiency were subjected to correlation analysis and indicate that their inhibition effect is closely related to E{sub HOMO}, E{sub LUMO}, and dipole moment (mu).

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

38 CFR 3.5 - Dependency and indemnity compensation.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Dependency and indemnity... ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation General § 3.5 Dependency and indemnity compensation. (a) Dependency and indemnity compensation. This term means a monthly payment made by...

DNA synthesis in permeabilized WI38 and MRC5 cells

International Nuclear Information System (INIS)

Griffiths, T.D.; Carpenter, J.G.

1980-01-01

DNA synthesis was examined in cultures of growing WI38 and MRC5 cells made permeable to deoxyribonucleotides. Cells from late passage cultures showed a reduced rate of deoxythymidine triphosphate (dTTP) uptake as compared to cells from early- to mid-passage cultures. This reduction became evident earlier in WI38 cultures (passage 33) than in MRC5 cultures (passage 41). Although this reduced rate of incorporation appeared to be primarily due to a reduced percentage of replicating (S phase) cells in later passage cultures, some effect on the rate of DNA synthesis in replicating cells was also evident

Effects of Cooling Rate on 6.5% Silicon Steel Ordering

Energy Technology Data Exchange (ETDEWEB)

Cui, Jun [Ames Lab. and Iowa State Univ., Ames, IA (United States); Macziewski, Chad [Iowa State Univ., Ames, IA (United States); Jensen, Brandt [Ames Lab., Ames, IA (United States); Ouyang, Gaoyuan [Iowa State Univ., Ames, IA (United States); Zhou, Lin [Ames Lab., Ames, IA (United States); Dennis, Kevin [Ames Lab., Ames, IA (United States); Zarkevich, Nikolai [Ames Lab., Ames, IA (United States); Jiang, Xiujuan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tang, Wei [Ames Lab., Ames, IA (United States); Zhou, Shihuai [Ames Lab., Ames, IA (United States); Simsek, Emrah [Ames Lab., Ames, IA (United States); Napolitano, Ralph [Iowa State Univ., Ames, IA (United States); Kramer, Matt [Ames Lab., Ames, IA (United States)

2017-03-02

Increasing Si content improves magnetic and electrical properties of electrical steel, with 6.5% Si as the optimum. Unfortunately, when Si content approaches 5.7%, the Fe-Si alloy becomes brittle. At 6.5%, the steel conventional cold rolling process is no longer applicable. The heterogeneous formation of B2 and D03 ordered phases is responsible for the embrittlement. The formation of these ordered phases can be impeded by rapid cooling. However, only the cooling rates of water and brine water were investigated. A comprehensive study of the effect of rapid cooling rate on the formation of the ordered phases was carried out by varying wheel speed and melt-injection rate. Thermal imaging employed to measure cooling rates while microstructures of the obtained ribbons are characterized using X-ray diffraction and TEM. The electrical, magnetic and mechanical properties are characterized using 4-pt probe, VSM, and macro-indentation methods. The relations between physical properties and ordered phases are established.

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.

Maxillary sinus floor augmentation with Bio-Oss or Bio-Oss mixed with autogenous bone as graft in animals

DEFF Research Database (Denmark)

Jensen, T; Schou, S; Stavropoulos, Andreas

2012-01-01

The objective of the present systematic review was to test the hypothesis of no differences between the use of Bio-Oss or Bio-Oss mixed with autogenous bone as graft for maxillary sinus floor augmentation (MSFA) applying the lateral window technique, as evaluated in animals. A MEDLINE (Pub...... of the graft improved significantly with increased proportion of Bio-Oss. Bone regeneration, bone-to-implant contact (BIC), biomechanical implant test values, and biodegradation of Bio-Oss after MSFA with Bio-Oss or Bio-Oss mixed with autogenous bone have never been compared within the same study in animals....... Thus, the hypothesis of no differences between the use of Bio-Oss and Bio-Oss mixed with autogenous bone as graft for MSFA could neither be confirmed nor rejected based on existing animal studies....

Paramagnetic defects in KH{sub 2}PO{sub 4} crystals with high concentration of embedded TiO{sub 2} nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Grachev, Valentin G., E-mail: grachev@physics.montana.edu; Tse, Romand; Malovichko, Galina I. [Physics Department, Montana State University, Bozeman, Montana 59717 (United States); Pritula, Igor M.; Bezkrovnaya, Olga N.; Kosinova, Anna V. [Institute for Single Crystals, NAS of Ukraine, Kharkiv (Ukraine)

2016-01-21

Qualitative transformations of spectra of Electron Paramagnetic Resonance, EPR, were found in KH{sub 2}PO{sub 4} crystals grown from liquor with 10{sup −5}–10{sup −1 }wt. % of anatase TiO{sub 2} nanoparticles in comparison with nominally pure KH{sub 2}PO{sub 4}. The nanoparticles have larger segregation coefficient for prismatic parts of the crystals than for pyramidal ones. Significant decrease in resonance absorption, complete disappearance of EPR lines of Fe{sup 3+} and Cr{sup 3+} centers, and appearance of four weak lines of equal intensities together with broad asymmetric lines with g-factors about 2.07–2.5 was observed in pyramidal parts grown with concentration of TiO{sub 2} nanoparticles larger than the threshold value 10{sup −2 }wt. %. The four lines were attributed to non-controlled impurity As substituted for P. In the presence of TiO{sub 2} nanoparticles, non-paramagnetic AsO{sub 4}{sup 3−} clusters trap electrons becoming AsO{sub 4}{sup 4−}. Disappearance of Fe{sup 3+} and Cr{sup 3+} centers was explained by their recharge to “EPR-silent” states and/or pairing at the surface of TiO{sub 2} nanoparticles.

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.

Brittle and ductile rupture of 16MND5 steel. Irradiation effect

International Nuclear Information System (INIS)

Al Mundheri, M.; Soulat, P.; Pineau, A.

1986-06-01

Toughness tests have been made on 16MND5 steel (A508Cl3 steel) - before and after irradiation at 290 0 C (3.10 19 n/cm 2 , E > 1 MeV). It is shown that toughness is lowered following the irradiation and that it is a decreasing function of the thickness of the test pieces. In parallel, tests on three geometries of entailed specimens, prepared in the non-irradiated material, have been made at different temperatures to apply the methodology of local approach of ductile-brittle rupture [fr

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.

Precipitation reactions in a beryllium-bearing stainless steel

International Nuclear Information System (INIS)

Carr, M.J.; Heiple, C.R.

1980-01-01

Precipitation reactions in a beryllium-bearing stainless steel alloy have been studied by TEM and electron diffraction for ageing temperatures between 400 0 and 900 0 C. The nominal composition of the alloy was 38% Ni - 21% Cr - 1% Mn - 0.5% Be - Bal Fe. Specimens were solutionized for one hour at 1150 0 C and water quenched. The ageing reaction was studied by hardness measurements for times between 0.5 and 16 hours. The TEM specimens dicussed herein were made from samples aged one hour

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.

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...

Fabrication and properties of strip casting 4.5 wt% Si steel thin sheet

Energy Technology Data Exchange (ETDEWEB)

Zu, Guoqing, E-mail: gz854@uowmail.edu.au [State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, NSW 2522 (Australia); Zhang, Xiaoming [State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); Zhao, Jingwei [School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, NSW 2522 (Australia); Wang, Yuqian [State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); Yan, Yi [School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, NSW 2522 (Australia); Li, Chengang; Cao, Guangming [State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China); Jiang, Zhengyi [School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, NSW 2522 (Australia)

2017-02-15

Three 4.5 wt% Si steel thin sheets with different thicknesses were efficiently fabricated by twin-roll strip casting, warm rolling and cold rolling followed by final annealing. A comprehensive investigation from the workability of the as-cast strip to the magnetic property of the produces was performed to illustrate the superiority of the new materials. The results show that the as-cast strip, which has a much lower Vickers hardness than that of the 6.5 wt% Si steel, is suitable for rolling processing. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies confirm that no ordering phase exists in the as-cast strip. The cold-rolled thin sheets exhibit good surface quality without edge cracks. Furthermore, all the three 4.5 wt% Si steel thin sheets possess relative strong <100>//ND texture and present high magnetic inductions and low iron losses after finial annealing. - Highlights: • 4.5 wt% Si as-cast sheet with excellent workability was produced by strip casting. • Three 4.5 wt% Si thin sheets were effectively fabricated by warm and cold rolling. • The microstructure and macro-texture of the thin sheets were elucidated. • High magnetic inductions and low iron losses were achieved simultaneously.

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

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

Effect of steel surface conditions on reinforcing steel corrosion in concrete exposed to marine environments

Directory of Open Access Journals (Sweden)

Anzola, E.

2005-09-01

Full Text Available Laboratory methods and experimental tests were deployed in the present study to evaluate corrosion in reinforced concrete exposed to marine environments. Reinforcing steel exhibiting two different surface conditions prior to embedment in concrete were studied, one the one hand to assess the electrochemical behaviour of the bars during exposure of the concrete specimens to a simulated marine environment, and on the other to determine the strength of the steel/concrete bond. The reinforced concrete specimens prepared were adapted as required for electrochemical potential and corrosion rate testing. A total of 56 7x15-cm cylindrical specimens containing 3/8" steel rods anchored at a depth of 11.5 cm were made to evaluate the steel / concrete bond and exposed to a natural marine environment for 28 or 190 days prior to testing. All the specimens were made with ready-mixed concrete. It may be concluded from the results of the corrosion tests on reinforcing steel with different surface conditions that the oxide initially covering the bars was dissolved and the steel passivated by the alkalinity in the concrete. The chief finding of the bonding study was that the layer of oxide formed in pre-embedment steel deterioration contributed to establishing a better bond.

En el contexto de esta investigación, se tomaron en consideración métodos y ensayos experimentales de laboratorio, que permiten hacer una evaluación de la corrosión del hormigón armado expuesto en ambientes marinos. Por una parte se evaluó el comportamiento electroquímico de dos condiciones de estados superficiales del acero embebido en el hormigón, exponiéndolo en un ambiente marino simulado y, por otra parte, se estudió la adherencia entre el acero y el hormigón, con los mismos estados superficiales usados para la evaluación electroquímica. Las probetas se fabricaron de hormigón con acero de refuerzo en su interior, adecuándolas para realizar los ensayos de potenciales

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

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...

Corrosion of stainless steel in alcohol solutions of the simplest carboxylic acids

International Nuclear Information System (INIS)

Vigdorovich, V.I.; Korneeva, T.V.; Tsygankova, L.E.

1975-01-01

The behaviour of stainless Kh18N10T steel is considered in the methanol and ethanol solutions of formic and acetic acids, respectively. Consideration is given to the effect of the concentration (C) of the acid (0.01-1.00 N), water (0.1-20.0 mass.%) and temperature (room temperature, 40 and 60 deg C). Curves of anodic polarization were plotted. In the course of time in 1.0 and 0.5 N anhydrous methanol solutions of HCOOH at room temperature in the absence of the external anode current one can observe an increase in the electrode potential. Continued reduction of the formic acid concentration results in an improvement on the initial potential (psi) and a practical constancy of psi in time. It is shown that depending on the acid concentration the additions of water are capable of producing both a passivating and an activating effect. It is assumed that the growth in the length of the hydrocarbon radical of carboxylic acid promotes the adsorption displacement of water and alcohols from the metal surface and enhancement of the corrosion rate

38 CFR 8.16 - Conversion of a 5-year level premium term policy as provided for under § 1904 of title 38 U.S.C.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Conversion of a 5-year level premium term policy as provided for under § 1904 of title 38 U.S.C. 8.16 Section 8.16 Pensions... Plan § 8.16 Conversion of a 5-year level premium term policy as provided for under § 1904 of title 38 U...

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

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

FANTOM5 CAGE profiles of human and mouse reprocessed for GRCh38 and GRCm38 genome assemblies.

Science.gov (United States)

Abugessaisa, Imad; Noguchi, Shuhei; Hasegawa, Akira; Harshbarger, Jayson; Kondo, Atsushi; Lizio, Marina; Severin, Jessica; Carninci, Piero; Kawaji, Hideya; Kasukawa, Takeya

2017-08-29

The FANTOM5 consortium described the promoter-level expression atlas of human and mouse by using CAGE (Cap Analysis of Gene Expression) with single molecule sequencing. In the original publications, GRCh37/hg19 and NCBI37/mm9 assemblies were used as the reference genomes of human and mouse respectively; later, the Genome Reference Consortium released newer genome assemblies GRCh38/hg38 and GRCm38/mm10. To increase the utility of the atlas in forthcoming researches, we reprocessed the data to make them available on the recent genome assemblies. The data include observed frequencies of transcription starting sites (TSSs) based on the realignment of CAGE reads, and TSS peaks that are converted from those based on the previous reference. Annotations of the peak names were also updated based on the latest public databases. The reprocessed results enable us to examine frequencies of transcription initiations on the recent genome assemblies and to refer promoters with updated information across the genome assemblies consistently.

Corrosion fatigue crack growth in clad low-alloy steels: Part 1, medium-sulfur forging steel

International Nuclear Information System (INIS)

James, L.A.; Poskie, T.J.; Auten, T.A.; Cullen, W.H.

1996-01-01

Corrosion fatigue crack propagation tests were conducted on a medium- sulfur ASTM A508-2 forging steel overlaid with weld-deposited Alloy EN82H cladding. The specimens featured semi-elliptical surface cracks penetrating approximately 6.3 mm of cladding into the underlying steel. The initial crack sizes were relatively large with surface lengths of 30.3--38.3 mm, and depths of 13.1--16.8 mm. The experiments were conducted in a quasi-stagnant low-oxygen (O 2 < 10 ppb) aqueous environment at 243 degrees C, under loading conditions (ΔK, R, and cyclic frequency) conductive to environmentally-assisted cracking (EAC) in higher-sulfur steels under quasi-stagnant conditions. Earlier experiments on unclad compact tension specimens of this heat of steel did not exhibit EAC, and the present experiments on semi-elliptical surface cracks penetrating cladding also did not exhibit EAC

Microstructure Evolution and Flow Stress Model of a 20Mn5 Hollow Steel Ingot during Hot Compression.

Science.gov (United States)

Liu, Min; Ma, Qing-Xian; Luo, Jian-Bin

2018-03-21

20Mn5 steel is widely used in the manufacture of heavy hydro-generator shaft due to its good performance of strength, toughness and wear resistance. However, the hot deformation and recrystallization behaviors of 20Mn5 steel compressed under high temperature were not studied. In this study, the hot compression experiments under temperatures of 850-1200 °C and strain rates of 0.01/s-1/s are conducted using Gleeble thermal and mechanical simulation machine. And the flow stress curves and microstructure after hot compression are obtained. Effects of temperature and strain rate on microstructure are analyzed. Based on the classical stress-dislocation relation and the kinetics of dynamic recrystallization, a two-stage constitutive model is developed to predict the flow stress of 20Mn5 steel. Comparisons between experimental flow stress and predicted flow stress show that the predicted flow stress values are in good agreement with the experimental flow stress values, which indicates that the proposed constitutive model is reliable and can be used for numerical simulation of hot forging of 20Mn5 hollow steel ingot.

Excellent corrosion resistance of 18Cr-20Ni-5Si steel in liquid Pb-Bi

International Nuclear Information System (INIS)

Kurata, Y.; Futakawa, M.

2004-01-01

The corrosion properties of three austenitic steels with different Si contents were studied under oxygen-saturated liquid Pb-Bi condition for 3000 h. The three austenitic steels did not exhibit appreciable dissolution of Ni and Cr at 450 deg. C. At 550 deg. C, the thick ferrite layer produced by dissolution of Ni and Cr was found in JPCA and 316SS with low Si contents while the protective oxide film composed of Si and O was formed on 18Cr-20Ni-5Si steel and prevented dissolution of Ni and Cr

Kub5-Hera, the human Rtt103 homolog, plays dual functional roles in transcription termination and DNA repair.

Science.gov (United States)

Morales, Julio C; Richard, Patricia; Rommel, Amy; Fattah, Farjana J; Motea, Edward A; Patidar, Praveen L; Xiao, Ling; Leskov, Konstantin; Wu, Shwu-Yuan; Hittelman, Walter N; Chiang, Cheng-Ming; Manley, James L; Boothman, David A

2014-04-01

Functions of Kub5-Hera (In Greek Mythology Hera controlled Artemis) (K-H), the human homolog of the yeast transcription termination factor Rtt103, remain undefined. Here, we show that K-H has functions in both transcription termination and DNA double-strand break (DSB) repair. K-H forms distinct protein complexes with factors that repair DSBs (e.g. Ku70, Ku86, Artemis) and terminate transcription (e.g. RNA polymerase II). K-H loss resulted in increased basal R-loop levels, DSBs, activated DNA-damage responses and enhanced genomic instability. Significantly lowered Artemis protein levels were detected in K-H knockdown cells, which were restored with specific K-H cDNA re-expression. K-H deficient cells were hypersensitive to cytotoxic agents that induce DSBs, unable to reseal complex DSB ends, and showed significantly delayed γ-H2AX and 53BP1 repair-related foci regression. Artemis re-expression in K-H-deficient cells restored DNA-repair function and resistance to DSB-inducing agents. However, R loops persisted consistent with dual roles of K-H in transcription termination and DSB repair.

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

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

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

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

The effect of initial microstructure on the final properties of press hardened 22MnB5 steels

International Nuclear Information System (INIS)

Järvinen, Henri; Isakov, Matti; Nyyssönen, Tuomo; Järvenpää, Martti; Peura, Pasi

2016-01-01

This paper addresses the relationship between initial microstructure and final properties of press hardened 22MnB5 steels. Four commercial 22MnB5 steels having different initial microstructures were investigated. An experimental press hardening equipment with a flat-die was used to investigate material behavior in the direct press hardening process. Two austenitizing treatments, 450 s and 180 s at 900 °C, were examined. Microstructural characterization with optical and scanning electron microscopes revealed a mixture of martensite and auto-tempered martensite after press hardening. Electron backscatter diffraction data of the transformed martensite was used to reconstruct grain boundary maps of parent austenite. Grain sizes of parent austenite (mean linear intercept) were measured for each material. In addition to microstructural evaluation, quasistatic and high strain rate tensile tests at strain rates of 5×10 −4 s −1 and 400 s −1 , respectively, were performed for press hardened samples. The results show that strength and uniform elongation depend on the initial microstructure of the 22MnB5 steel, when parameters typical to the direct press hardening process are used. Parent austenite grain size was shown to influence the morphology of the transformed martensite, which in turn affects the strength and uniform elongation after press hardening. The tensile properties of the press hardened materials are almost strain rate independent in the studied strain rate range. The obtained results can be used to optimize the properties of 22MnB5 steels in the direct press hardening process. In addition, the here revealed connection between the parent austenite grain size and final steel properties should be taken into account in the development of new press hardening steel grades for automotive industry.

The effect of initial microstructure on the final properties of press hardened 22MnB5 steels

Energy Technology Data Exchange (ETDEWEB)

Järvinen, Henri, E-mail: henri.jarvinen@tut.fi [Department of Materials Science, Tampere University of Technology, P.O.Box 589, FI-33101 Tampere (Finland); Isakov, Matti; Nyyssönen, Tuomo [Department of Materials Science, Tampere University of Technology, P.O.Box 589, FI-33101 Tampere (Finland); Järvenpää, Martti [SSAB Europe Oy, Harvialantie 420, FI-13300 Hämeenlinna (Finland); Peura, Pasi [Department of Materials Science, Tampere University of Technology, P.O.Box 589, FI-33101 Tampere (Finland)

2016-10-31

This paper addresses the relationship between initial microstructure and final properties of press hardened 22MnB5 steels. Four commercial 22MnB5 steels having different initial microstructures were investigated. An experimental press hardening equipment with a flat-die was used to investigate material behavior in the direct press hardening process. Two austenitizing treatments, 450 s and 180 s at 900 °C, were examined. Microstructural characterization with optical and scanning electron microscopes revealed a mixture of martensite and auto-tempered martensite after press hardening. Electron backscatter diffraction data of the transformed martensite was used to reconstruct grain boundary maps of parent austenite. Grain sizes of parent austenite (mean linear intercept) were measured for each material. In addition to microstructural evaluation, quasistatic and high strain rate tensile tests at strain rates of 5×10{sup −4} s{sup −1} and 400 s{sup −1}, respectively, were performed for press hardened samples. The results show that strength and uniform elongation depend on the initial microstructure of the 22MnB5 steel, when parameters typical to the direct press hardening process are used. Parent austenite grain size was shown to influence the morphology of the transformed martensite, which in turn affects the strength and uniform elongation after press hardening. The tensile properties of the press hardened materials are almost strain rate independent in the studied strain rate range. The obtained results can be used to optimize the properties of 22MnB5 steels in the direct press hardening process. In addition, the here revealed connection between the parent austenite grain size and final steel properties should be taken into account in the development of new press hardening steel grades for automotive industry.

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

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

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.

Corrosion Prevention of Steel Reinforcement in 7.5% NaCl Solution using Pure Magnesium Anode

Science.gov (United States)

Iyer Murthy, Yogesh; Gandhi, Sumit; Kumar, Abhishek

2018-03-01

The current work investigates the performance of pure Magnesium on corrosion prevention of steel reinforcements by way of sacrificial anoding. Two set of six steel reinforcements were tested for half-cell potential, weight loss, anode efficiency and tensile strength for each of the sacrificial anodes in a high chloride atmosphere of 7.5% NaCl in tap water. Significant reduction in weight of anode was observed during the initial 12 days. The reduction in weight of steel reinforcements tied with anodes was found to be negligible, while that of reinforcements without anodes was significantly higher. Five distinct zones of corrosion were observed during the test. The tensile strength of steel cathodically protected by Mg alloy anodes was found less affected. It could be concluded that pure Mg anode provides an effective way of corrosion mitigation.

Investigation of electrochemical corrosion behavior in a 3.5 wt.% NaCl solution of boronized dual-phase steel

International Nuclear Information System (INIS)

Kayali, Yusuf; Anaturk, Bilal

2013-01-01

Highlights: ► Corrosion behaviors in a 3.5% NaCl solution of boronized Dual-Phase (DP) steels were examined. ► The martensite ratio increased with an increase in the intercritical annealing temperature. ► The corrosion resistance decreased with increase of the martensite ratio. ► The boride layer increased the corrosion resistance of DP steel 2–3-fold. ► The superior properties of DP steel as well as poor corrosion properties were improved by the boriding process. - Abstract: In this study, corrosion behaviors of boronized and non-boronized dual-phase steel were investigated with Tafel extrapolation and linear polarization methods in a 3.5 wt.% NaCl solution. Microstructure analyses show that the boride layer on the dual-phase steel surface had a flat and saw smooth morphology. It was detected by X-ray diffraction (XRD) analysis that the boride layer contained FeB and Fe 2 B phases. The amount of martensite increases with an increase in the intercritical annealing temperature. Both the amount of martensite and the morphology of the phase constituents have an influence on the corrosion behavior of dual-phase steel. A higher corrosion tendency was observed with an increased amount of martensite. The corrosion resistance of boronized dual-phase steel is higher compared with that of dual-phase steel

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)

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

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.

On the inhibition of mild steel corrosion by 4-amino-5-phenyl-4H-1, 2, 4-trizole-3-thiol

International Nuclear Information System (INIS)

Musa, Ahmed Y.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Takriff, Mohd Sobri; Daud, Abdul Razak; Kamarudin, Siti Kartom

2010-01-01

The corrosion inhibition of mild steel in a 2.5 M H 2 SO 4 solution by 4-amino-5-phenyl-4H-1, 2, 4-trizole-3-thiol (APTT) was studied at different temperatures, utilising open circuit potential, potentiodynamic and impedance measurements. The results indicate that APTT performed as an excellent mixed-type inhibitor for mild steel corrosion in a 2.5 M H 2 SO 4 solution and that the inhibition efficiencies increased with the inhibitor concentration but decreased proportionally with temperature. The kinetic and thermodynamic parameters for adsorption of APTT on the mild steel surface were calculated. A chemisorption mechanism of APTT molecules on the mild steel surface was proposed based on the thermodynamic adsorption parameters.

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.

Synthesis, Crystal Structure, and Nonlinear Optical Properties of a New Alkali and Alkaline Earth Metal Carbonate RbNa5Ca5(CO3)8

OpenAIRE

Qiaoling Chen; Min Luo

2016-01-01

A new nonlinear optical (NLO) material, RbNa5Ca5(CO3)8, has been synthesized by the hydrothermal method. The crystal structure is established by single-crystal X-ray diffraction. RbNa5Ca5(CO3)8 crystallizes in the hexagonal crystal system with space group P63mc (No. 186). The structure of RbNa5Ca5(CO3)8 can be described as the adjacent infinite [CaCO3]∞ layers lying in the a-b plane bridged through standing-on-edge [CO3] groups by sharing O atoms (two-fold coordinated) to build a framework wi...

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

Alloy spreading and filling of gaps in brazing of VDU-2 and KhN50VMTYuB heat resistant nickel alloys with VPr3K and VPr10 alloys

International Nuclear Information System (INIS)

Shapiro, A.E.; Podol'skij, B.A.; Lepisko, M.R.; Borzyak, A.G.; Moryakov, V.F.; Rostislavskaya, T.T.

1984-01-01

A study was made on contact interaction of VDU-2 and KhN50VMTYuB alloys with VPr3K and VPr10 alloys at 1325 and 1220 deg C in argon and industrial vacuum. The contact angles and wettability indexes were determined. The solders fill the vertical gaps of up to 0.25 mm width through 80 mm height. Spreading and filling of gaps proceeds better during soldering in argon with boron trifluoride addition as compared to soldering in industrial vacuum. VPr10 alloy is divided into two phases when wetting KhN50VMTYuB alloy: fusible one on the base of nickel-chromium-manganese solution and infusible one on the base of nickel-niobium eutectics. The square of fusible phase spreading is 2.5...3 times larger as compared to infusible one

Corrosion study of API 5L x-series pipeline steels in 3.5% NaCl solution under varying conditions

International Nuclear Information System (INIS)

Shahid, M.; Qureshi, M.I.; Farooq, M.U.; Khan, M.I.

2003-01-01

Pipelines provide convenient and efficient means for mass transportation of variety of fluids, such as oil and gas, over varying distances. In the last two decades or so, pipeline designers focused mainly on the usage of larger sizes and higher operating pressures for achieving higher transportation efficiency. This has been accomplished through the provision of steels with progressive increase in yield strength coupled with good weldability and sufficient toughness to restrict crack propagation. In addition to higher strength and toughness, developing pipeline technologies have required improved resistance to corrosion, which has been tried with specific alloy additions and special control over non-metallic inclusions. Corrosion investigations were carried out on various grades of pipeline steels (API 5L X-46, X-52, X-56, X-60 and X- 70) under varying environmental conditions. This paper describes the results pertaining to corrosion behavior of the steels in 3.5% NaCl solutions in stagnant, turbulent and deaerated conditions. It was found that all grades corrode in this solution and their corrosion potentials and corrosion currents are in close vicinity of each other. Turbulent solutions, however, have shown an increase in corrosion rates whereas deaeration has revealed a relative decrease in aggressivity of the electrolyte. (author)

Treatment of open-hearth steel by lime-silicate melts

International Nuclear Information System (INIS)

Sokolov, G.A.; Kungurov, V.M.; Sergeev, A.G.

1975-01-01

Because of the scarcity of Al 2 O 3 , slags were developed containing larger amounts of SiO 2 and MgO and with addition of 4-5% CaF 2 . The 2 slags prepared in the laboratory had basicities (CaO-SiO 2 ratios) of 2.07 and 2.65. They contained 12.8 and 13.9% Al 2 O vs. 38-42% for the control and were obtained from sources such as clay. The extents of desulfurization of low-alloy steels using the new slags, a slag containing 22.2% Al 2 O 3 and a control slag were approximately the same and were also satisfactory (61-70%) for 4 C steels. The S distributions between slag and metal were calculated. The slag basicity vs. % desulfurization showed maximum of the latter for 2.5-2.8 basicity. The sizes of oxide and sulfide inclusions were smaller for the former and about the same for the latter for the new slags than for the control. The mechanical properties, especially the impact strength at +20 and -70deg, of the steel from the ingots prepared with the new slags were much better than those of the control. A cost analysis showed savings of approximately 70% compared with the usual slag

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

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.

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)

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

Correlation of microstructure and low cycle fatigue properties for 13.5Cr1.1W0.3Ti ODS steel

International Nuclear Information System (INIS)

He, P.; Klimenkov, M.; Möslang, A.; Lindau, R.; Seifert, H.J.

2014-01-01

Reduced activation oxide dispersion strengthened (ODS) steels are prospective structural materials for the blanket system and first wall components in Tokamak-type fusion reactors. Under the pulsed operation, these components will be predominantly subjected to cyclic thermal–mechanical loading which leads to inevitable fatigue damage. In this work, strain controlled isothermal fatigue tests were conducted for 13.5Cr1.1W0.3Ti ODS steel at 550 °C. The total strain range varied from 0.54% to 0.9%. After thermomechanical processing, 13.5CrWTi–ODS steel exhibits a remarkable lifetime extension with a factor of 10–20 for strain ranges Δε ⩽ 0.7%. 13.5Cr ODS steel shows no cyclic softening at all during the whole testing process irrespective of the strain range. TEM observations reveal ultrastable grain structure and constant dislocation densities around 10 14 m −2 , independent of the number of cycles or the applied strain amplitude. The presence of the stabilized ultrafine Y–Ti–O dispersoids enhances the microstructural stability and therefore leads to outstanding fatigue resistance for 13.5Cr1.1W0.3Ti–ODS steel

Correlation of microstructure and low cycle fatigue properties for 13.5Cr1.1W0.3Ti ODS steel

Energy Technology Data Exchange (ETDEWEB)

He, P., E-mail: pei.he@kit.edu; Klimenkov, M.; Möslang, A.; Lindau, R.; Seifert, H.J.

2014-12-15

Reduced activation oxide dispersion strengthened (ODS) steels are prospective structural materials for the blanket system and first wall components in Tokamak-type fusion reactors. Under the pulsed operation, these components will be predominantly subjected to cyclic thermal–mechanical loading which leads to inevitable fatigue damage. In this work, strain controlled isothermal fatigue tests were conducted for 13.5Cr1.1W0.3Ti ODS steel at 550 °C. The total strain range varied from 0.54% to 0.9%. After thermomechanical processing, 13.5CrWTi–ODS steel exhibits a remarkable lifetime extension with a factor of 10–20 for strain ranges Δε ⩽ 0.7%. 13.5Cr ODS steel shows no cyclic softening at all during the whole testing process irrespective of the strain range. TEM observations reveal ultrastable grain structure and constant dislocation densities around 10{sup 14} m{sup −2}, independent of the number of cycles or the applied strain amplitude. The presence of the stabilized ultrafine Y–Ti–O dispersoids enhances the microstructural stability and therefore leads to outstanding fatigue resistance for 13.5Cr1.1W0.3Ti–ODS steel.

Reaction of uranium and plutonium carbides with austenitic steels

International Nuclear Information System (INIS)

Mouchnino, M.

1967-01-01

The reaction of uranium and plutonium carbides with austenitic steels has been studied between 650 and 1050 deg. C using UC, steel and (UPu)C, steel diffusion couples. The steels are of the type CN 18.10 with or without addition of molybdenum. The carbides used are hyper-stoichiometric. Tests were also carried out with UCTi, UCMo, UPuCTi and UPuCMo. Up to 800 deg. C no marked diffusion of carbon into stainless steel is observed. Between 800 and 900 deg. C the carbon produced by the decomposition of the higher carbides diffuses into the steel. Above 900 deg. C, decomposition of the monocarbide occurs according to a reaction which can be written schematically as: (U,PuC) + (Fe,Ni,Cr) → (U,Pu) Fe 2 + Cr 23 C 6 . Above 950 deg. C the behaviour of UPuCMo and that of the titanium (CN 18.12) and nickel (NC 38. 18) steels is observed to be very satisfactory. (author) [fr

Magnetic losses reduction in grain oriented silicon steel by pulse and continuous fiber laser processing

Science.gov (United States)

Petryshynets, Ivan; Kováč, František; Puchý, Viktor; Šebek, Martin; Füzer, Ján; Kollár, Peter

2018-04-01

The present paper shows the impact of different laser scribing conditions on possible reduction of magnetic losses in grain oriented electrical steel sheets. The experimental Fe-3%Si steel was taken from industrial line after final box annealing. The surface of investigated steel was subjected to fiber laser processing using both pulse and continuous scribing regimes in order to generate residual thermal stresses inducing the magnetic domains structure refinement. The magnetic losses of experimental samples before and after individual laser scribing regimes were tested in AC magnetic field with 50Hz frequency and induction of 1.5T. The most significant magnetic losses reduction of 38% was obtained at optimized conditions of continuous laser scribing regime. A semi quantitative relationship has been found between the domain patterns and the used fiber laser processing.

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

Effect of decreased hot-rolling reduction treatment on fracture toughness of low-alloy structural steels

Science.gov (United States)

Tomita, Yoshiyuki

1990-09-01

Commercial low-alloy structural steels, 0.45 pct C (AISI 1045 grade), 0.40 pct C-Cr-Mo (AISI 4140 grade), and 0.40 pct C-Ni-Cr-Mo (AISI 4340 grade), have been studied to determine the effect of the decreased hot-rolling reduction treatment (DHRRT) from 98 to 80 pct on fracture toughness of quenched and highly tempered low-alloy structural steels. The significant conclusions are as follows: (1) the sulfide inclusions were modified through the DHRRT from a stringer (mean aspect ratio: 16.5 to 17.6) to an ellipse (mean aspect ratio: 3.8 to 4.5), independent of the steels studied; (2) the DHRRT significantly improved J Ic in the long-transverse and shorttransverse orientations, independent of the steels studied; and (3) the shelf energy in the Charpy V-notch impact test is also greatly improved by the DHRRT, independent of testing orientation and steels studied; however, (4) the ductile-to-brittle transition temperature was only slightly affected by the DHRRT. The beneficial effect on the J Ic is briefly discussed in terms of a crack extension model involving the formation of voids at the inclusion sites and their growth and eventual linking up through the rupture of the intervening ligaments by local shear.

Corrosion mitigation of J55 steel in 3.5% NaCl solution by a macrocyclic inhibitor

Energy Technology Data Exchange (ETDEWEB)

Singh, Ambrish [State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Southwest Petroleum University), Chengdu, Sichuan 610500 (China); Department of Chemistry, LFTS, Lovely Professional University, Phagwara, Punjab 144402 (India); Lin, Yuanhua, E-mail: yhlin28@163.com [State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Southwest Petroleum University), Chengdu, Sichuan 610500 (China); Obot, I.B. [Centre of Research Excellence in Corrosion, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Ebenso, Eno E. [Department of Chemistry, School of Mathematical & Physical Sciences, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho 2735 (South Africa); Material Science Innovation & Modelling (MaSIM) Focus Area, Faculty of Agriculture, Science and Technology, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho 2735 (South Africa); Ansari, K.R.; Quraishi, M.A. [Department of Applied Chemistry, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005, Uttar Pradesh (India)

2015-11-30

Graphical abstract: SECM studies revealed decrease of steady current in the presence of inhibitor while it increased for 3.5% NaCl solution that acted as the conductor. - Highlights: • J55 steel protection in 3.5% NaCl solution saturated with CO{sub 2} by HPT. • Potentiodynamic polarization curves reveal that the actions of HPT are mixed type. • The adsorption of HPT obeys the Langmuir adsorption isotherm. • Scanning electrochemical microscopy is used to discuss the insulated and conductive surface. - Abstract: 1,2,4,7,9,10-Hexaazacyclo-pentadeca-10,15-dien-3,5,6,8-tetraone (HPT) a macrocyclic compound has been studied using electrochemical methods and scanning electrochemical microscopy (SECM) techniques. The R{sub ct} values increased and C{sub dl} values decreased with the increase in concentration of the inhibitor. The corrosion inhibition of J55 steel in 3.5 wt.% NaCl solution saturated with CO{sub 2} by polarization studies revealed that HPT acted as a mixed type inhibitor. The adsorption of HPT on the J55 steel surface obeyed the Langmuir adsorption isotherm. The thermodynamic parameters (K{sub ads}, ΔG°{sub ads}) were also computed and discussed.

Corrosion mitigation of J55 steel in 3.5% NaCl solution by a macrocyclic inhibitor

International Nuclear Information System (INIS)

Singh, Ambrish; Lin, Yuanhua; Obot, I.B.; Ebenso, Eno E.; Ansari, K.R.; Quraishi, M.A.

2015-01-01

Graphical abstract: SECM studies revealed decrease of steady current in the presence of inhibitor while it increased for 3.5% NaCl solution that acted as the conductor. - Highlights: • J55 steel protection in 3.5% NaCl solution saturated with CO 2 by HPT. • Potentiodynamic polarization curves reveal that the actions of HPT are mixed type. • The adsorption of HPT obeys the Langmuir adsorption isotherm. • Scanning electrochemical microscopy is used to discuss the insulated and conductive surface. - Abstract: 1,2,4,7,9,10-Hexaazacyclo-pentadeca-10,15-dien-3,5,6,8-tetraone (HPT) a macrocyclic compound has been studied using electrochemical methods and scanning electrochemical microscopy (SECM) techniques. The R ct values increased and C dl values decreased with the increase in concentration of the inhibitor. The corrosion inhibition of J55 steel in 3.5 wt.% NaCl solution saturated with CO 2 by polarization studies revealed that HPT acted as a mixed type inhibitor. The adsorption of HPT on the J55 steel surface obeyed the Langmuir adsorption isotherm. The thermodynamic parameters (K ads , ΔG° ads ) were also computed and discussed.

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

Application of artificial neural network and adaptive neuro-fuzzy inference system to investigate corrosion rate of zirconium-based nano-ceramic layer on galvanized steel in 3.5% NaCl solution

International Nuclear Information System (INIS)

Mousavifard, S.M.; Attar, M.M.; Ghanbari, A.; Dadgar, M.

2015-01-01

Highlights: • Film formation of Zr-based conversion coating under different conditions was investigated. • We study the effect of some parameters on anticorrosion performance of conversion coating. • Optimization of processing conditions for surface treatment of galvanized steel was obtained. • Modeling and predicting corrosion current density of treated surfaces was performed using ANN and ANFIS. - Abstract: A nano-ceramic Zr-based conversion solution was prepared and optimization of Zr concentration, pH, temperature and immersion time for the treatment of hot-dip galvanized steel (HDG) was performed. SEM microscopy was utilized to investigate the microstructure and film formation of the layer and the anticorrosion performance of conversion coating was studied using polarization test. Artificial intelligence systems (ANN and ANFIS) were applied on the data obtained from polarization test and the models for predicting corrosion current density values were attained. The outcome of these models showed proper predictability of the methods. The influence of input parameters was discussed and the optimized conditions for Zr-based conversion layer formation on the galvanized steel were obtained as follows: pH 3.8–4.5, Zr concentration of about 100 ppm, ambient temperature and immersion time of about 90 s

Application of artificial neural network and adaptive neuro-fuzzy inference system to investigate corrosion rate of zirconium-based nano-ceramic layer on galvanized steel in 3.5% NaCl solution

Energy Technology Data Exchange (ETDEWEB)

Mousavifard, S.M. [Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Attar, M.M., E-mail: attar@aut.ac.ir [Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Ghanbari, A. [Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Dadgar, M. [Textile Engineering Department, Neyshabur University, Neyshabur (Iran, Islamic Republic of)

2015-08-05

Highlights: • Film formation of Zr-based conversion coating under different conditions was investigated. • We study the effect of some parameters on anticorrosion performance of conversion coating. • Optimization of processing conditions for surface treatment of galvanized steel was obtained. • Modeling and predicting corrosion current density of treated surfaces was performed using ANN and ANFIS. - Abstract: A nano-ceramic Zr-based conversion solution was prepared and optimization of Zr concentration, pH, temperature and immersion time for the treatment of hot-dip galvanized steel (HDG) was performed. SEM microscopy was utilized to investigate the microstructure and film formation of the layer and the anticorrosion performance of conversion coating was studied using polarization test. Artificial intelligence systems (ANN and ANFIS) were applied on the data obtained from polarization test and the models for predicting corrosion current density values were attained. The outcome of these models showed proper predictability of the methods. The influence of input parameters was discussed and the optimized conditions for Zr-based conversion layer formation on the galvanized steel were obtained as follows: pH 3.8–4.5, Zr concentration of about 100 ppm, ambient temperature and immersion time of about 90 s.

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

Endothelium-Derived 5-Methoxytryptophan Protects Endothelial Barrier Function by Blocking p38 MAPK Activation.

Directory of Open Access Journals (Sweden)

Ling-Yun Chu

Full Text Available The endothelial junction is tightly controlled to restrict the passage of blood cells and solutes. Disruption of endothelial barrier function by bacterial endotoxins, cytokines or growth factors results in inflammation and vascular damage leading to vascular diseases. We have identified 5-methoxytryptophan (5-MTP as an anti-inflammatory factor by metabolomic analysis of conditioned medium of human fibroblasts. Here we postulated that endothelial cells release 5-MTP to protect the barrier function. Conditioned medium of human umbilical vein endothelial cells (HUVECs prevented endothelial hyperpermeability and VE-cadherin downregulation induced by VEGF, LPS and cytokines. We analyzed the metabolomic profile of HUVEC conditioned medium and detected 5-MTP but not melatonin, serotonin or their catabolites, which was confirmed by enzyme-linked immunosorbent assay. Addition of synthetic pure 5-MTP preserved VE-cadherin and maintained barrier function despite challenge with pro-inflammatory mediators. Tryptophan hydroxylase-1, an enzyme required for 5-MTP biosynthesis, was downregulated in HUVECs by pro-inflammatory mediators and it was accompanied by reduction of 5-MTP. 5-MTP protected VE-cadherin and prevented endothelial hyperpermeability by blocking p38 MAPK activation. A chemical inhibitor of p38 MAPK, SB202190, exhibited a similar protective effect as 5-MTP. To determine whether 5-MTP prevents vascular hyperpermeability in vivo, we evaluated the effect of 5-MTP administration on LPS-induced murine microvascular permeability with Evans blue. 5-MTP significantly prevented Evans blue dye leakage. Our findings indicate that 5-MTP is a new class of endothelium-derived molecules which protects endothelial barrier function by blocking p38 MAPK.

Experimental and quantum chemical simulations on the corrosion inhibition of mild steel by 3-((5-(3,5-dinitrophenyl)-1,3,4-thiadiazol-2-yl)imino)indolin-2-one

Science.gov (United States)

Al-Azawi, Khalida F.; Mohammed, Iman Mahdi; Al-Baghdadi, Shaimaa B.; Salman, Taghried A.; Issa, Hamsa A.; Al-Amiery, Ahmed A.; Gaaz, Tayser Sumer; Kadhum, Abdul Amir H.

2018-06-01

Iraq has been one of the most extensive oil and natural gas industries in the world. The corrosion of mild steel is costly and insufficiency process. It is responsible for great loss in manufacture and environment. Natural and organic inhibitors have been utilized for a long time to inhibit the corrosion. Selected thiadiazol derivative, namely 3-((5-(3,5-dinitrophenyl)-1,3,4-thiadiazol-2-yl)imino)indolin-2-one (TDIO) was investigated for it inhibitive impacts in 1 M HCl medium on corrosion of mild steel using weight loss and scanning electron microscope techniques. The maximum inhibition efficiency up to 90.7% at the maximum inhibitor concentration 0.5 mM. Surface morphology of results demonstrated that TDIO formed adsorbed film on surface of mild steel in hydrochloric acid solution. Give molecular based clarifications to the inhibitive impacts of the studied. The interactions between mild steel surface and the inhibitor molecules have been undertaken to further corroborate the methodological results.

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.

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.

The influence of surface roughness on the hydrogen permeation of type API 5L-X52 steel; Influencia del acabado superficial en la permeacion de hidrogeno del acero API 5L-X52 steel

Energy Technology Data Exchange (ETDEWEB)

Requiz, R; Vera, N; Camero, S

2004-07-01

The influence of surface reoughness on the corrosion and hydrogen permeation behaviour was evaluated on a type API 5L-52 steel in dearated 0.1M NaSO{sub 4} at pH=2. Potentiodynamic polarization curves were emplyed to determine the electrochemical behaviour of the steel, while the Devanathan-Stachurski technique was used to estimate the hydrogen permeation rate. Additionally, the surface roughness profiles were obtained in order to correlate the changes in the hydrogen perkeation rate with different metal surface finishings. The obtained results clearly demonstrate that when the roughness parameters have larger values, the cathodic current of hydrogen evolution increases while the hydrogen entry rate decreases. This effect can be attributed to the microstructural defects induced at the steel surface, such as dislocations, which increase the catalytic activity of the atomic hydrogen favouring its recombination. Also, these defects could allow the atomic hydrogen to remain adsorbed on the steel surface. Both effects could hinder the hydrogen diffusion into the metal since the possibility for this atom of becoming absorbed has been reduced. (Author) 16 refs.

Effect of 0.2 and 0.5% Ti on the microstructure and mechanical properties of 13Cr supermartensitic stainless steel

Science.gov (United States)

Lian, Yong; Huang, Jinfeng; Zhang, Jin; Zhang, Cheng; Gao, Wen; Zhao, Chao

2015-11-01

The effect that a 0, 0.2, and 0.5 wt.% titanium content has on the microstructure and mechanical properties of 13Cr supermartensitic stainless steel was investigated using an optical microscope, transmission electron microscope, and X-ray diffraction. The resultant microstructures of the three steels were tempered martensite with a reversed austenite dispersed throughout the matrix. Additionally, the formation of Cr-rich carbides was suppressed by stable Ti(C, N), which improved the strength without severely decreasing in the Ti-microalloyed steel toughness. Nano-precipitation of Ni3Ti was found for the 0.5 wt.% Ti steel during tempering, which significantly increased the strength, but decreased the toughness. The reversed austenite volume fraction also significantly influenced the mechanical properties.

Active and passive fire protection system in academic building KH. Mas Mansur, Islamic University of Indonesia

Directory of Open Access Journals (Sweden)

Suryoputro M. Ragil

2018-01-01

Full Text Available According to the theory of fire triangle, the existence of combustible materials, heat, and oxygen can cause fire disaster. KH. Mas Mansur building, Islamic University of Indonesia has a fire protection, but rarely to be checked regularly and the number of equipment is less standard as well as the lack of an evacuation route map to facilitate the evacuation process. Inside the building also does not provide safety signs such as the evacuation directions, exit, and warning in case of fire. Therefore, researchers analysed the infrastructure of prevention and control in the building KH. Mas Mansur. Researchers used the method of observation, interviews, and checklist to know the condition directly, and compare with the standard regulations. Results concordance rate of existing infrastructure is 67% fire extinguisher, hydrant box 56%, 71% alarms, sprinkler 0%, 40% detectors, emergency doors 71%, 50% emergency stairs, assembly point 0% and directions 0%. The current results were below the standard of at least 80%. As for recommendations, researchers create a new evacuation map then put the existing infrastructure according to standard regulations, and it had consulted with the specialist of Occupational Safety and Health in the field of fire.

Hot Deformation Behavior and a Two-Stage Constitutive Model of 20Mn5 Solid Steel Ingot during Hot Compression

Directory of Open Access Journals (Sweden)

Min Liu

2018-03-01

Full Text Available 20Mn5 steel is widely used in the manufacture of heavy hydro-generator shaft forging due to its strength, toughness, and wear resistance. However, the hot deformation and recrystallization behaviors of 20Mn5 steel compressed under a high temperature were not studied. For this article, hot compression experiments under temperatures of 850–1200 °C and strain rates of 0.01 s−1–1 s−1 were conducted using a Gleeble-1500D thermo-mechanical simulator. Flow stress-strain curves and microstructure after hot compression were obtained. Effects of temperature and strain rate on microstructure are analyzed. Based on the classical stress-dislocation relationship and the kinetics of dynamic recrystallization, a two-stage constitutive model is developed to predict the flow stress of 20Mn5 steel. Comparisons between experimental flow stress and predicted flow stress show that the predicted flow stress values are in good agreement with the experimental flow stress values, which indicates that the proposed constitutive model is reliable and can be used for numerical simulation of hot forging of 20Mn5 solid steel ingot.

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

Catalytic conversion of biomass pyrolysis-derived compounds with chemical liquid deposition (CLD) modified ZSM-5.

Science.gov (United States)

Zhang, Huiyan; Luo, Mengmeng; Xiao, Rui; Shao, Shanshan; Jin, Baosheng; Xiao, Guomin; Zhao, Ming; Liang, Junyu

2014-03-01

Chemical liquid deposition (CLD) with KH550, TEOS and methyl silicone oil as the modifiers was used to modify ZSM-5 and deposit its external acid sites. The characteristics of modified catalysts were tested by catalytic conversion of biomass pyrolysis-derived compounds. The effects of different modifying conditions (deposited amount, temperature, and time) on the product yields and selectivities were investigated. The results show KH550 modified ZSM-5 (deposited amount of 4%, temperature of 20°C and time of 6h) produced the maximum yields of aromatics (24.5%) and olefins (16.5%), which are much higher than that obtained with original ZSM-5 catalyst (18.8% aromatics and 9.8% olefins). The coke yield decreased from 44.1% with original ZSM-5 to 26.7% with KH550 modified ZSM-5. The selectivities of low-molecule-weight hydrocarbons (ethylene and benzene) decreased, while that of higher molecule-weight hydrocarbons (propylene, butylene, toluene, and naphthalene) increased comparing with original ZSM-5. Copyright © 2013 Elsevier Ltd. All rights reserved.

Radiofrequency cold plasma nitrided carbon steel: Microstructural and micromechanical characterizations

International Nuclear Information System (INIS)

Bouanis, F.Z.; Bentiss, F.; Bellayer, S.; Vogt, J.B.; Jama, C.

2011-01-01

Highlights: → C38 carbon steel samples were plasma nitrided using a radiofrequency (rf) nitrogen plasma discharge. → RF plasma treatment enables nitriding for non-heated substrates. → The morphological and chemical analyses show the formation of a uniform thickness on the surface of the nitrided C38 steel. → Nitrogen plasma active species diffuse into the samples and lead to the formation of Fe x N. → The increase in microhardness values for nitrided samples with plasma processing time is interpreted by the formation of a thicker nitrided layer on the steel surface. - Abstract: In this work, C38 carbon steel was plasma nitrided using a radiofrequency (rf) nitrogen plasma discharge on non-heated substrates. General characterizations were performed to compare the chemical compositions, the microstructures and hardness of the untreated and plasma treated surfaces. The plasma nitriding was carried out on non-heated substrates at a pressure of 16.8 Pa, using N 2 gas. Surface characterizations before and after N 2 plasma treatment were performed by means of the electron probe microanalysis (EPMA), X-ray photoelectron spectroscopy (XPS) and Vickers microhardness measurements. The morphological and chemical analysis showed the formation of a uniform structure on the surface of the nitrided sample with enrichment in nitrogen when compared to untreated sample. The thickness of the nitride layer formed depends on the treatment time duration and is approximately 14 μm for 10 h of plasma treatment. XPS was employed to obtain chemical-state information of the plasma nitrided steel surfaces. The micromechanical results show that the surface microhardness increases as the plasma-processing time increases to reach, 1487 HV 0.005 at a plasma processing time of 8 h.

Radiofrequency cold plasma nitrided carbon steel: Microstructural and micromechanical characterizations

Energy Technology Data Exchange (ETDEWEB)

Bouanis, F.Z. [Universite Lille Nord de France, F-59000 Lille (France); Unite Materiaux et Transformations (UMET), Ingenierie des Systemes Polymeres, CNRS UMR 8207, ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Bentiss, F. [Laboratoire de Chimie de Coordination et d' Analytique, Faculte des Sciences, Universite Chouaib Doukkali, B.P. 20, M-24000 El Jadida (Morocco); Bellayer, S.; Vogt, J.B. [Universite Lille Nord de France, F-59000 Lille (France); Unite Materiaux et Transformations (UMET), Ingenierie des Systemes Polymeres, CNRS UMR 8207, ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France); Jama, C., E-mail: charafeddine.jama@ensc-lille.fr [Universite Lille Nord de France, F-59000 Lille (France); Unite Materiaux et Transformations (UMET), Ingenierie des Systemes Polymeres, CNRS UMR 8207, ENSCL, BP 90108, F-59652 Villeneuve d' Ascq Cedex (France)

2011-05-16

Highlights: {yields} C38 carbon steel samples were plasma nitrided using a radiofrequency (rf) nitrogen plasma discharge. {yields} RF plasma treatment enables nitriding for non-heated substrates. {yields} The morphological and chemical analyses show the formation of a uniform thickness on the surface of the nitrided C38 steel. {yields} Nitrogen plasma active species diffuse into the samples and lead to the formation of Fe{sub x}N. {yields} The increase in microhardness values for nitrided samples with plasma processing time is interpreted by the formation of a thicker nitrided layer on the steel surface. - Abstract: In this work, C38 carbon steel was plasma nitrided using a radiofrequency (rf) nitrogen plasma discharge on non-heated substrates. General characterizations were performed to compare the chemical compositions, the microstructures and hardness of the untreated and plasma treated surfaces. The plasma nitriding was carried out on non-heated substrates at a pressure of 16.8 Pa, using N{sub 2} gas. Surface characterizations before and after N{sub 2} plasma treatment were performed by means of the electron probe microanalysis (EPMA), X-ray photoelectron spectroscopy (XPS) and Vickers microhardness measurements. The morphological and chemical analysis showed the formation of a uniform structure on the surface of the nitrided sample with enrichment in nitrogen when compared to untreated sample. The thickness of the nitride layer formed depends on the treatment time duration and is approximately 14 {mu}m for 10 h of plasma treatment. XPS was employed to obtain chemical-state information of the plasma nitrided steel surfaces. The micromechanical results show that the surface microhardness increases as the plasma-processing time increases to reach, 1487 HV{sub 0.005} at a plasma processing time of 8 h.

Treatment of open-hearth steel by lime-silicate melts

Energy Technology Data Exchange (ETDEWEB)

Sokolov, G A; Kungurov, V M; Sergeev, A G

1975-07-01

Because of the scarcity of Al/sub 2/O/sub 3/, slags were developed containing larger amounts of SiO/sub 2/ and MgO and with addition of 4-5% CaF/sub 2/. The 2 slags prepared in the laboratory had basicities (CaO-SiO/sub 2/ ratios) of 2.07 and 2.65. They contained 12.8 and 13.9% Al/sub 2/O vs. 38-42% for the control and were obtained from sources such as clay. The extents of desulfurization of low-alloy steels using the new slags, a slag containing 22.2% Al/sub 2/O/sub 3/ and a control slag were approximately the same and were also satisfactory (61-70%) for 4 C steels. The S distributions between slag and metal were calculated. The slag basicity vs. % desulfurization showed maximum of the latter for 2.5-2.8 basicity. The sizes of oxide and sulfide inclusions were smaller for the former and about the same for the latter for the new slags than for the control. The mechanical properties, especially the impact strength at +20 and -70deg, of the steel from the ingots prepared with the new slags were much better than those of the control. A cost analysis showed savings of approximately 70% compared with the usual slag.

Magnetic losses reduction in grain oriented silicon steel by pulse and continuous fiber laser processing

Directory of Open Access Journals (Sweden)

Ivan Petryshynets

2018-04-01

Full Text Available The present paper shows the impact of different laser scribing conditions on possible reduction of magnetic losses in grain oriented electrical steel sheets. The experimental Fe-3%Si steel was taken from industrial line after final box annealing. The surface of investigated steel was subjected to fiber laser processing using both pulse and continuous scribing regimes in order to generate residual thermal stresses inducing the magnetic domains structure refinement. The magnetic losses of experimental samples before and after individual laser scribing regimes were tested in AC magnetic field with 50Hz frequency and induction of 1.5T. The most significant magnetic losses reduction of 38% was obtained at optimized conditions of continuous laser scribing regime. A semi quantitative relationship has been found between the domain patterns and the used fiber laser processing.

Influence of metallurgical phase transformation on crack propagation of 15-5PH stainless steel and 16MND5 low carbon steel

International Nuclear Information System (INIS)

Liu, J.

2012-01-01

This study focuses on the effects of phase transformations on crack propagation. We want to understand the changes of fracture toughness during welding. In this work, fracture toughness is expressed by J-integral. There are many experimental methods to obtain the critical toughness JIC but they are impractical for our investigation during phase transformation. That is the reason why we have proposed a method coupling mechanical tests, digital image correlation and finite element simulation. The fracture tests are implemented on pre-cracked single edge notched plate sample which is easy for machining and heat conduct during phase transformation. The tests are conducted at different temperatures until rupture. Digital image correlation gives us the displacement information on every sample. Each test is then simulated by finite element where the fracture toughness is evaluated by the method G-Theta at the crack propagation starting moment found by potential drop method and digital image correlation technical. Two materials have been studied, 15Cr-5Ni martensitic precipitation hardening stainless steel and 16MND5 ferritic low carbon steel. For these two materials, different test temperatures were chosen before, during and after phase transformation for testing and failure characterization of the mechanical behavior. Investigation result shows that metallurgical phase transformation has an influence on fracture toughness and further crack propagation. For 15-5PH, the result of J1C shows that the as received 15-5PH has higher fracture toughness than the one at 200 C. The toughness is also higher than the original material after one cycle heat treatment probably due to some residual austenite. Meanwhile, pure austenite 15-5PH at 200 C has higher fracture toughness than pure martensitic 15-5PH at 200 C. For 16MND5, the result also proves that the phase transformation affects fracture toughness. The as received material has bigger J1C than the situation where it was heated

First attempts towards the early detection of fatigued substructures using cyclic-loaded 20 MnMoNi 5 5 steel

International Nuclear Information System (INIS)

Dobmann, G.; Seibold, A.

1992-01-01

Materials subjected to cyclic loading undergo substructural changes which may affect service life. The low alloy, fine-grained structural steel 20 MnMoNi 5 5 is used to demonstrate how substructural changes detected using TEM techniques are a function of the number of cycles undergone. For a given cyclic loading the usage factor η=N/N f =0.5 can be derived. Initial investigations using nondestructive examination methods have indicated that substructural changes and magnetic variables can be correlated. (orig.)

Fracture behaviour of steel 20 MnMoNi 5 5 under stress wave loading

International Nuclear Information System (INIS)

Clos, R.; Schreppel, U.; Veit, P.; Zencker, U.; Specht, E.

1994-01-01

Crack initiation in fine grained 20 MnMoNi 5 5 steel has been investigated under stress wave loading conditions in the temperature range from -50 C to 20 C by a loading setup similar the ''Split Hopkinson Pressure Bar'' technique. For temperatures up to 20 C, fracture occurs by cleavage and K Id approaches and falls below the reference fracture toughness, while at room temperature stable crack growth occurs with a J i close to the static initiation value of the J-integral. The analysis of the crack tip configuration suggests that stable crack growth is the result of the following simultaneously induced stochastical processes: generation of constrained local microcracks, blunting of the individual crack tips and the deformation of material bridges at different regions along the crack tip front. (orig.)

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

The FEM Analysis of Stress Distribution in front of the Crack Tip and Fracture Process in the Elements of Modified and Unmodified Cast Steel G17CrMo5-5

Directory of Open Access Journals (Sweden)

Pała Robert

2016-09-01

Full Text Available The article presents influence of modification of the low-alloy cast steel G17CrMo5-5 by rare earth metals on stress distribution in front of the crack at the initial moment of the crack extension. Experimental studies include determination of strength and fracture toughness characteristics for unmodified (UM and modified (M cast steel. In the numerical computations, experimentally tested specimens SEN(B were modelled. The true stress–strain curves for the UM and M cast steel are used in the calculation. The stress distributions in front of the crack were calculated at the initial moment of the crack extension. On the basis of data on the particle size inclusions in the UM and M cast steel, and the calculated stress distributions was performed an assessment of the possibility of the occurrence of cleavage fracture. The analysis results indicate that at room temperature for the UM cast steel, there is a possibility of cleavage fracture, while for the M cast steel occurrence of cleavage fracture is negligible.

Stress corrosion cracking of 350 maraging steel in 3.5 Wt. % NaCl solution

International Nuclear Information System (INIS)

Hussain, I.; Hussain, T.; Tauqir, A.; Hashmi, F.H.; Khan, A.Q.

1993-01-01

Stress corrosion behavior of 350 maraging steel in 3.5 wt.% NaCl solution was investigated. The results suggest that the steel is susceptible to stress corrosion cracking as the time to failure was always considerably shorter, as compared to those in air at the same stress level. The fracture mode was nearly intergranular and occasionally transgranular. There was no definite trend for the different modes of failure. The strain rate effect was also considered and the results show that the stress corrosion cracks were absent at strain rate high than 1.97 x 10/sup -4/S/sup -1/ and lower than 1.29 x 10/sup -7/S/sup -1/. The critical strain rate range was found to be between 6.4 x 10/sup -7/ to 3.24 x10/sup -5/S /sup -1/. (author)

Liquid steel analysis by laser-induced plasma spectroscopy

International Nuclear Information System (INIS)

Gruber, J.

2002-11-01

When a nanosecond pulsed laser is focused onto a sample and the intensity exceeds a certain threshold, material is vaporized and a plasma is formed above the sample surface. The laser-light becomes increasingly absorbed by inverse bremsstrahlung and by photo-excitation and photo-ionization of atoms and molecules. The positive feedback, by which the number of energetic electrons for ionization is increased in an avalanche-like manner under the influence of laser-light, is the so-called optical breakdown. Radiating excited atoms and ions within the expanding plasma plume produce a characteristic optical emission spectrum. A spectroscopic analysis of this optical emission of the laser-induced plasma permits a qualitative and quantitative chemical analysis of the investigated sample. This technique is therefore often called laser-induced plasma spectroscopy (LIPS) or laser-induced breakdown spectroscopy (LIBS). LIPS is a fast non-contact technique, by which solid, liquid or gaseous samples can be analyzed with respect to their chemical composition. Hence, it is an appropriate tool for the rapid in-situ analysis of not easily accessible surfaces for process control in industrial environments. In this work, LIPS was studied as a technique to determine the chemical composition of solid and liquid steel. A LIPS set-up was designed and built for the remote and continuous in-situ analysis of the steel melt. Calibration curves were prepared for the LIPS analysis of Cr, Mn, Ni and Cu in solid steel using reference samples with known composition. In laboratory experiments an induction furnace was used to melt steel samples in crucibles, which were placed at a working distance of 1.5 m away from the LIPS apparatus. The response of the LIPS system was monitored on-line during the addition of pure elements to the liquid steel bath within certain concentration ranges (Cr: 0.11 - 13.8 wt%, Cu: 0.044 - 0.54 wt%, Mn: 1.38 - 2.5 wt%, Ni: 0.049 - 5.92 wt%). The analysis of an element

Evaluation of protective effect of deposits formed by naphthenic corrosion and sulfidation on carbon steel and steel 5Cr-0.5Mo exposed in atmospheric distillation fractions

Directory of Open Access Journals (Sweden)

Gloria Duarte

2017-05-01

Full Text Available Refining of so-called opportunity crude oils with a high level of naphthenic acids and sulfur compounds has been increasing interest due to limited availability of light crude oils, however, considerable corrosive effects in the processing to high temperature on pipes and distillation towers mainly by the attack of naphthenic acids and sulfur compounds; sulfur compounds could be corrosive or can reduce the attack of naphthenic acids due to the formation of sulfides layers on the metal surface. In this work was evaluated the performance of deposits formed on the surface of carbon steel AISI SAE 1020 and 5% Cr-0.5% Mo steel exposed in crude oil fractions obtained from atmospheric distillation tower. For this, gravimetric tests were performed in dynamic autoclave using metal samples pre-treated in a crude oil fraction obtained from the atmospheric distillation tower of the Crude Distillation Unit (CDU # 1 in order to form layers of sulfides on the surface of the two materials and subsequently to expose pre-treated and non-pretreated samples in two different crude oil fractions obtained from atmospheric distillation tower of Crude Distillation Unit (CDU # 2. The evaluation showed that the samples pretreated decreased tendency to corrosion by naphthenic acids and sulfidation compared to untreated samples.

Reactor thread-joint metal with corrosion resistant coating material low cycle fatigue

International Nuclear Information System (INIS)

Gorynin, V.I.; Kondratyev, S.Yu.

1991-01-01

The results of test carried out show that the Ni-P plating which was thermally treated in inert medium, provide the dependence of the reactor equipment studs in the high-concentrated medium of leakage for a period of up to 3000 hours. The Al and aluminized platings of the studs made of steel 38 KhN 3 MFA don't provide their corrosion dependence in the reactor medium. Cr plating provides the dependence during 500 hours. The reported test allows to recommend Ni-P plating to depend the studs in the conditions of the effect of the high-concentrated leakage medium, containing KOH, H 3 BO 3 and NaCl. (author)

Effects of Additives on the Corrosion Resistance of Iron Aluminides(Fe-38at.%AI-5at.%Cr)

International Nuclear Information System (INIS)

Choi, H. C.; Kim, C. W.; Joo, S. M.; Choi, D. C.; Kim, K. H.

2001-01-01

The effects of additives on the corrosion resistance of iron aluminides(Fe-38at.%AI-5at.%Cr) were investigated using potentiostat. The specimens were cast by vacuum arc melting. The subsequent homogenization was carried out in Ar gas atmosphere at 1000 .deg. C for 7 days. The corroded surfaces of the tested specimens were observed using an optical microscope and a scanning electron microscope(SEM) after electrochemical tests were carried out in various solutions. While the Hf addition to Fe-38at.%AI-5at.%Cr resulted in equiaxial microstructure, the Zr addition resulted in dendritic microstructure. However, no change in microstructure was observed when Mo was added. The addition of Mo to Fe-38at.%AI-5at.%Cr intermetallic compound was found to increase the pitting potential, which improved the resistance against the pitting corrosion attack. The addition of Hf and Zr resulted in a higher activation current density and a lower pitting potential. These results may indicate that the dendrite structure played a major role in decreasing the pitting corrosion resistance of Fe-38at.%AI-5at%Cr intermetallic compound. The Mo addition to Fe-38at.%AI-5at.%Cr decreased the number and size of pits. In the case of Zr addition, the pits nucleated and grew remarkably at dendritic branches

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

Nitrided steel 38CrN3MAFA for supporting elements in nuclear power plants; Vysokoazotistaya stal` tipa 38HN3MAFA dlya krepezhnikh detajlej reaktorov AEhS

Energy Technology Data Exchange (ETDEWEB)

Rasheva, I; Argirov, Kh; Stojchev, T [Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. po Metaloznanie i Tekhnologiya na Metalite

1996-12-31

Nitride doping of steel at different concentrations is achieved by counter-pressure casting in nitrogen ambience. A new type of steel is developed containing 0.05-0.2% N{sub 2}. It is compared to a standard 34NiCrMoV145 steel (DIN). The mechanical properties are improved significantly after a two-stage thermal treatment and are as follows: fluidity limit R{sub 0}.2>=1045 MPa, relative elongation A>=15%, relative shortening Z>=62%, impact viscosity KCU >= 1 MJ/m{sup 2}. The quench hardening consists of heating to 800-850{sup o} C in oil and cooling to 600{sup o} C in air. The steel is suitable for rotors, turbines, compressor shafts and reactor supporting elements in nuclear power plants. 3 refs., 6 figs., 6 tabs.

Electric dipole moment in KH{sub 2}PO{sub 4} systematically modified by proton irradiation

Energy Technology Data Exchange (ETDEWEB)

Jin Kweon, Jung; Lee, Cheol Eui [Department of Physics and Institute for Nano Science, Korea University, Seoul 136-713 (Korea, Republic of); Noh, S. J.; Kim, H. S. [Department of Applied Physics, Dankook University, Yongin 448-701 (Korea, Republic of)

2012-01-01

We have carried out an impedance spectroscopy study on a series of proton-irradiated KH{sub 2}PO{sub 4} (KDP) systems. A systematic modification was observed in the transverse dipole moment of the proton-irradiated KDP systems, associated with hydrogen-ion displacements, as obtained from dielectric constant measurements by using a mean-field approximation. Besides, intercorrelation of the charge transport with the dielectric properties was revealed, both having closely to do with the hydrogen-bond modification.

Bubble formation upon crystallization of high nitrogen iron base alloys

International Nuclear Information System (INIS)

Svyazhin, A.G.; Sivka, E.; Skuza, Z.

2000-01-01

A study is made into the conditions of nitrogen bubble formation during crystallization of unalloyed iron, alloys of Fe-O, Fe-O-S systems, steels 1Kh13, 0Kh18N9 and a two-phase Fe-11%Cr-1%Mo-0.2%V steel. It is revealed that the amount of bubbles in a high nitrogen steel casting increases with a degree of nitrogen supersaturation and decreases with a cooling rate growth and with a rise of surfactant concentration in the metal. In sound castings a nitrogen content can be increased due to a cooling rate growth, nitrogen dilution with inert gas, an increase of nitrogen pressure during crystallization as well as due to the introduction of such surfactants as sulphur, selenium, tellurium, tin [ru

Dynamics of water around the complex structures formed between the KH domains of far upstream element binding protein and single-stranded DNA molecules

Energy Technology Data Exchange (ETDEWEB)

Chakraborty, Kaushik; Bandyopadhyay, Sanjoy, E-mail: sanjoy@chem.iitkgp.ernet.in [Molecular Modeling Laboratory, Department of Chemistry, Indian Institute of Technology, Kharagpur 721302 (India)

2015-07-28

Single-stranded DNA (ss-DNA) binding proteins specifically bind to the single-stranded regions of the DNA and protect it from premature annealing, thereby stabilizing the DNA structure. We have carried out atomistic molecular dynamics simulations of the aqueous solutions of two DNA binding K homology (KH) domains (KH3 and KH4) of the far upstream element binding protein complexed with two short ss-DNA segments. Attempts have been made to explore the influence of the formation of such complex structures on the microscopic dynamics and hydrogen bond properties of the interfacial water molecules. It is found that the water molecules involved in bridging the ss-DNA segments and the protein domains form a highly constrained thin layer with extremely retarded mobility. These water molecules play important roles in freezing the conformational oscillations of the ss-DNA oligomers and thereby forming rigid complex structures. Further, it is demonstrated that the effect of complexation on the slow long-time relaxations of hydrogen bonds at the interface is correlated with hindered motions of the surrounding water molecules. Importantly, it is observed that the highly restricted motions of the water molecules bridging the protein and the DNA components in the complexed forms originate from more frequent hydrogen bond reformations.

Morphology and Performance of 5Cr5MoV Casting Die Steel in the Process of Surfacing

Science.gov (United States)

Song, Yulai; Kong, Xiangrui; Yang, Pengcong; Fu, Hongde; Wang, Xuezhu

2017-12-01

To investigate the microstructures and mechanical properties of the deposited metal on surface of die steel, two layer of weld-seam were prepared on the surface of 5Cr5MoV die steel by arc surfacing. The surface microstructures and microhardness were characterized by scanning electron microscopy, energy dispersive spectrometer and Vickers microhardness tester, respectively. The effect of load on the abrasion resistance and wear mechanism of the base metal and surfacing metal was studied by pin-on-disk tribometer. The results showed that martensite and retained austenite exist in weld-seam, both of them grow up in the form of dendrites and equiaxed grains and microhardness reach 774.2HV. The microstructures of the quenching zone mainly consist of martensite and retained austenite, while tempered martensite is the dominant phase in partial quenching zone. The abrasion resistance of the surfacing metal is superior to the base metal based on the results of wear test. The wear rates of surfacing metal and base metal raise with the increase of load. The wear rates of base metal raise extremely when the load reach 210N. Both of two kinds of materials have the similar wear mechanism, namely, abrasive wear at low load, oxidative wear and adhesive wear at high load.

Am/Cm TTR testing - 3/8-inch glass beads evaluation in CIM5

International Nuclear Information System (INIS)

Witt, D. C.

2000-01-01

To facilitate the procurement and handling of the glass former for Am/Cm vitrification in the F-Canyon MPPF, 1/4 inch and 3/8 inch diameter glass beads were purchased from Corning for evaluation in the 5 inch Cylindrical Induction Melter (CIM5). Prior to evaluating the beads in the CIM5, tests were conducted in the Drain Tube Test Stand (DTTS) with 1/4 inch beads, 3/8 inch beads, and a 50/50 mixture to identify any process concerns. Results of the DTTS tests are summarized in Attachment 1. A somewhat larger volume expansion was experienced in all three DTTS runs as compared to a standard run using cullet. Further testing of the use of glass beads in the CIM5 was requested by the Design Authority as Task 1.02 of Technical Task Request 99-MNSS/SE-006. Since the Technical Task Plan was not yet approved, the completion of this task was conducted under an authorization request approved by the SRTC Laboratory Director, S. Wood. This request is included as Attachment 2

Sàng khôn as A Theorizing Tool in Mobility Education

Directory of Open Access Journals (Sweden)

Ngoc Ba Doan

2017-02-01

Full Text Available The current virtual and physical mobility of humans, ideas, knowledge and epistemologies has major implications for education, especially in settings where English is seen as the default medium of instruction. While diversity is inherent in mobility, English-only pedagogy is a denial of the richness and potential of diverse resources learners bring with them through their mobility. This paper reports a philosophical stance and pedagogical practices employed by a lecturer in English language education at an Australian university. It argues that students’ full linguistic resources and epistemologies, known as sàng khôn, contribute to their agency and can be used as tools to theorise new knowledge in the context of their mobility education.

Evolution of mechanical properties of boron/manganese 22MnB5 steel under magnetic pulse influences

International Nuclear Information System (INIS)

Falaleev, A P; Meshkov, V V; Vetrogon, A A; Shymchenko, A V

2016-01-01

The boron/manganese 22MnB5 steel can be noted as the widely used material for creation of details, which must withstand high amount of load and impact influences. The complexity and high labor input of restoration of boron steel parts leads to growing interest in the new forming technologies such as magnetic pulse forming. There is the investigation of the evolution of mechanical properties of 22MnB5 steel during the restoration by means of magnetic pulse influence and induction heating. The heating of 22MnB5 blanks to the temperature above 900 0 C was examined. The forming processes at various temperatures (800, 900 and 950 0 C) were performed during the experiments. The test measurements allowed to obtain the relationships between the strain and the operation parameters such as induced current, pulse discharge time and the operation temperature. Based on these results the assumption about usage of these parameters for control of deformation process was made. Taking into account the load distribution and the plasticity evolution during the heating process, the computer simulation was performed in order to obtain more clear strain distribution through the processed area. The measurement of hardness and the comparison with the properties evolution during hot stamping processes confirmed the obtained results. (paper)

Corrosive effect of oil's accompanying water polluted with H2S over steel (API 5L X-52)

International Nuclear Information System (INIS)

Cueli Corugedo, Alexander; Adames Montero, Yosmari; Rivera Beltran, Yischy; Davis Harriet, Juan

2013-01-01

The corrosion from the steel to the carbon in the sale oil pipage conduction, is a serious problem, due to the material and economical looses they cause, damaging even in some cases the productive field. The purpose of this study is to determine the aggressiveness of the oil's water layer, polluted with H 2 S ( g) , over the steel of pipelines' construction (API 5L X-52), taking into account the temperature variations which take place during the transportation of the oil, using the electrochemical techniques of polarisation resistance (LPR) and electrochemical noise. It is pretended to determine the velocity of steel corrosion in the oil's water layer polluted with H 2 S through electrochemical techniques. It was shown that the temperature increases and the concentration of H 2 S to 500 ppm in the oil's accompanying water emphasizes the corrosion phenomenon experienced by the steel (9, 188 0 mm/year to 70℃).The results of the electrochemical noise spectrums and the values of the localisation ?s index calculated, shown the presence of corrosion on the steel surface (API 5L X-52).This result was complemented through optic Microscopy which permits to corroborate the poor adherence of the sulphur layers deposited on the metal that increase the appearance of events found with the temperature increase and the concentration of H 2 S in the environment studied

Development of advanced low alloy steel for nuclear RPV

Energy Technology Data Exchange (ETDEWEB)

Lee, H. C.; Shin, K. S.; Lee, S. H.; Lee, B. J. [Seoul National Univ., Seoul (Korea)

2000-04-01

Low carbon low alloy steels are used in nuclear power plants as pressure vessel, steam generator, etc. Nuclear pressure vessel material requires good combination of strength/ toughness, good weldability and high resistance to neutron irradiation and corrosion fatigue. For SA508III steels, most widely used in the production of nuclear power plant, attaining toughness is more difficult than strength. When taking into account the loss of toughness due to neutron irradiation, attaining as low transition temperature as possible prior to operation is a critical task in the production of nuclear pressure vessels. In the present study, we investigated detrimental microstructural features of SA508III steels to toughness, then alloy design directions to achieve improved mechanical properties were devised. The next step of alloy design was determined based on phase equilibrium thermodynamics and obtained results. Low carbon low alloy steels having low transition temperatures with enough strength and hardenability were developed. Microstructure and mechanical properties of HAZ of SA508III steels and alloy designed steels were investigated. 22 refs., 147 figs., 38 tabs. (Author)

Microstructure and tensile properties of high strength duplex ferrite-martensite (DFM) steels

International Nuclear Information System (INIS)

Chakraborti, P.C.; Mitra, M.K.

2007-01-01

Duplex ferrite-martensite (DFM) steels containing 38-80% martensite of varying morphologies were developed by batch intercritical annealing of a commercial variety vanadium bearing 0.2% C-Mn steel at different temperatures. Microstructures before intercritical annealing were found to control the morphological distribution of the phase constituents of the developed DFM steels. Tensile test results revealed best strength-ductility combination for finely distributed lamellar ferrite-martensite phase aggregate containing ∼60% martensite developed from a prior martensitic structure. Taking consideration of the modified law of mechanical mixture the experimental tensile strength data of the developed DFM steels has been formulated with some success and very good estimation for tensile strengths of pure ferrite and low carbon martensite has been made from tensile strength data of DFM steels

Nickel and its alloys as perspective materials for intermediate temperature steam electrolysers operating on proton conducting solid acids as electrolyte

DEFF Research Database (Denmark)

Nikiforov, Aleksey; Petrushina, Irina; Jensen, Jens Oluf

2012-01-01

Several stainless steels, nickel-based alloys, Ta-coated stainless steel, niobium, nickel, platinum and gold were evaluated as possible materials for use in the intermediate temperature water electrolysers. The corrosion resistance was measured in molten KH2PO4 as simulated conditions corresponding...

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.

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.

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.

Heavy-Section Steel Irradiation Program. Volume 5, No. 2, Progress report, April 1994--September 1994

International Nuclear Information System (INIS)

Corwin, W.R.

1995-07-01

The Heavy-Section Steel Irradiation (HSSI) Program has been established with its primary goal to provide a thorough, quantitative assessment of the effects of neutron irradiation on the material behavior and the fracture toughness properties of typical pressure-vessel steels as they relate to light-water RPV integrity. Effects of specimen size; material chemistry; product form and microstructure; irradiation fluence, flux, temperature, and spectrum; and postirradiation annealing are being examined on a wide range of fracture properties. The HSSI Program is arranged into 14 tasks: (1) program management, (2) fracture toughness curve shift in high-copper weldments (Series 5 and 6), (3) K lc and K la curve shifts in low upper-shelf (LUS) welds (Series 8), (4) irradiation effects in a commercial LUS weld (Series 10), (5) irradiation effects on weld heat-affected zone and plate materials (Series 11), (6) annealing effects in LUS welds (Series 9), (7) microstructural and microfracture analysis of irradiation effects, (8) in-service irradiated and aged material evaluations, (9) Japan Power Development Reactor (JPDR) steel examination, (10) fracture toughness curve shift method, (11) special technical assistance, (12) technical assistance for Joint Coordinating Committee on Civilian Nuclear Reactor Safety (JCCCNRS) Working Groups 3 and 12, (13) correlation monitor materials, and (14) test reactor coordination. Progress on each task is reported

The Factor of Structure and Mechanical Properties in the Production of Critical Fixing Hardware 38XA

Directory of Open Access Journals (Sweden)

G.V. Pachurin

2016-09-01

Full Text Available Fixing hardware made of carbon, high-carbon, and alloyed wires is one of the widespread critical parts in mechanical engineering. The characteristics of fixtures and fasteners and their performance figures are assessed at all stages of steel-making operation, from the choice of burden stock for metal smelting to the method of preparing calibrated rolled metal parts and upsetting end products. Material used for producing long high-duty bolts must be both sufficiently strong and ductile, have homogeneous mechanical properties and chemistry, and no inner or surface defects. When manufacturing fasteners, hot-rolled metal is often plastically deformed by drafting before cold upsetting, and all unacceptable defects are removed by the expensive procedure of lathe-turning. Moreover, this technology of metal processing entails losses of up to 5.5 % in chips. This paper suggests a resource-efficient and environmentally friendlier fabrication method for calibrated rolled metal items made of steel 38XA, 9.65 mm diameter, for cold die-forging of high-duty bolts used in automotive engines, which helps spare expensive lathe-machining processes. Moreover, rolled steel produced using this technology is characterized by high resistance to plastic deformation when cold, which leads to increase n wear-resistance of tools in cold die-forging of bolts.

Effect of wheel speed on magnetic and mechanical properties of melt spun Fe-6.5 wt.% Si high silicon steel

Science.gov (United States)

Ouyang, Gaoyuan; Jensen, Brandt; Tang, Wei; Dennis, Kevin; Macziewski, Chad; Thimmaiah, Srinivasa; Liang, Yongfeng; Cui, Jun

2018-05-01

Fe-Si electric steel is the most widely used soft magnetic material in electric machines and transformers. Increasing the silicon content from 3.2 wt.% to 6.5 wt.% brings about large improvement in the magnetic and electrical properties. However, 6.5 wt.% silicon steel is inherited with brittleness owing to the formation of B2 and D03 ordered phase. To obtain ductility in Fe-6.5wt.% silicon steel, the ordered phase has to be bypassed with methods like rapid cooling. In present paper, the effect of cooling rate on magnetic and mechanical properties of Fe-6.5wt.% silicon steel is studied by tuning the wheel speed during melt spinning process. The cooling rate significantly alters the ordering and microstructure, and thus the mechanical and magnetic properties. X-ray diffraction data shows that D03 ordering was fully suppressed at high wheel speeds but starts to nucleate at 10m/s and below, which correlates with the increase of Young's modulus towards low wheel speeds as tested by nanoindentation. The grain sizes of the ribbons on the wheel side decrease with increasing wheel speeds, ranging from ˜100 μm at 1m/s to ˜8 μm at 30m/s, which lead to changes in coercivity.

Cymbopogon citratus and NaNO2 Behaviours in 3.5% NaCl-Immersed Steel-Reinforced Concrete: Implications for Eco-Friendly Corrosion Inhibitor Applications for Steel in Concrete

Directory of Open Access Journals (Sweden)

Joshua Olusegun Okeniyi

2018-01-01

Full Text Available This paper studies behaviours of Cymbopogon citratus leaf-extract and NaNO2, used as equal-mass admixture models, in 3.5% NaCl-immersed steel-reinforced concrete by nondestructive electrochemical methods and by compressive-strength improvement/reduction effects. Corrosion-rate, corrosion-current, and corrosion-potential constitute electrochemical test-techniques while compressive-strength effect investigations followed ASTM C29 and ASTM C33, in experiments using positive-controls for the electrochemical and compressive-strength studies. Analyses of the different electrochemical test-results mostly portrayed agreements on reinforcing-steel anticorrosion effects by the concentrations of natural plant and of chemical admixtures in the saline/marine simulating-environment and in the distilled H2O (electrochemical positive control of steel-reinforced concrete immersions. These indicated that little amount (0.0833% cement for concrete-mixing of Cymbopogon citratus leaf-extract was required for optimal inhibition efficiency, η = 99.35%, on reinforcing-steel corrosion, in the study. Results of compressive-strength change factor also indicated that the 0.0833% Cymbopogon citratus concentration outperformed NaNO2 admixture concentrations also in compressive-strength improvement effects on the NaCl-immersed steel-reinforced concrete. These established implications, from the study, on the suitability of the eco-friendly Cymbopogon citratus leaf-extract for replacing the also highly effective NaNO2 inhibitor of steel-in-concrete corrosion in concrete designed for the saline/marine service-environment.

Tritium diffusivity and solubility measurements in Z 5 NCTD 26-15 (A 286) austenitic stainless steel

International Nuclear Information System (INIS)

Broudeur, R.; Fidelle, J.P.; Devaux, J.; Rapin, M.

A method of calculation that allows the diffusion coefficient and solubility of a gas in a metal to be expressed by analysis of its entry kinetics during a metal charging test under given temperature and pressure is cited. This method is applied to tritium charging of Z 5 NCTD 26-15 (A 286) austenitic stainless steel. The special equipment necessary for such tests is described. The diffusion coefficient and solubility of tritium in this steel are determined in tests made between 350 and 450 0 C under a pressure of 10 bars. (U.S.)

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

Technology Roadmap Research Program for the Steel Industry

Energy Technology Data Exchange (ETDEWEB)

Joseph R. Vehec

2010-12-30

The steel industry's Technology Roadmap Program (TRP) is a collaborative R&D effort jointly sponsored by the steel industry and the United States Department of Energy. The TRP program was designed to develop new technologies to save energy , increase competitiveness, and improve the environment. TRP ran from July, 1997 to December, 2008, with a total program budget of $38 million dollars. During that period 47 R&D projects were performed by 28 unique research organizations; co-funding was provided by DOE and 60 industry partners. The projects benefited all areas of steelmaking and much know-how was developed and transferred to industry. The American Iron and Steel Institute is the owner of all intellectual property developed under TRP and licenses it at commercial rates to all steelmakers. TRP technologies are in widespread use in the steel industry as participants received royalty-free use of intellectual property in return for taking the risk of funding this research.

Current status of stainless steel industry and development of stainless steel

International Nuclear Information System (INIS)

Lee, Yong Deuk; Lee, Chan Soo; Kim Kwang Tae

2000-01-01

Stainless steel is not only clean and smooth in its surface, but also it is superior in quality in terms of corrosion resistance and strength. So that, it is widely in use in the field of construction, chemical installations, and other industries. Growth of stainless steel industry started since the steel technology was developed for mass production in 1960s. Since then stainless steel industry grew rapidly on account of diversified development in this field and growth rate went up to 5.8% per year comparable to 2.3% of steel growth. The rapid growth is attributed to significant industry developments in Europe and Japan in the years of 1970s and 1980s. In addition to these the expansion of stainless steel industry in Korea and Taiwan. Presently Korea produces about 120,000 tons of stainless steel and occupies about 8% of international market. This means Korea become the second largest single country in world in stainless steel production. Moreover Korea is to reinforce its domestic production line by affiliating production companies, increasing of production capability, and specializing in types of stainless steel. This paper is to describe activity of material development, and types of stainless steel for industry use. (Hong, J. S.)

Irradiation effects in low-alloy reactor pressure vessel steels (Heavy-Section Steel Technology program series 4 and 5)

International Nuclear Information System (INIS)

McGowan, J.J.; Nanstad, R.K.; Thoms, K.R.; Menke, B.H.

1985-01-01

This report presents studies on the irradiation effects in low-alloy reactor pressure vessel steels. The Fourth Heavy-Section Steel Technology (HSST) Irradiation Series, almost completed, was aimed at elastic-plastic and fully plastic fracture toughness of low-copper weldments (''current practice welds''). A typical nuclear pressure vessel plate steel was included for statistical purposes. The Fifth HSST Irradiation Series, now in progress, is aimed at determining the shape of the K/sub IR/ curve after significant radiation-induced shift of the transition temperatures. This series includes irradiated test specimens of thicknesses up to 100 mm and weldment compositions typical of early nuclear power reactor pressure vessel welds. 27 refs., 22 figs

Hydrogen embrittlement of the 22 Cr5 Ni austeno-ferritic stainless steel. Role of the microstructure

International Nuclear Information System (INIS)

Iacoviello, Francesco

1997-01-01

Austenitic-ferritic stainless steels are characterised by very good mechanical properties and by a high corrosion resistance, especially to stress-corrosion and to pitting. However, their duplex structure shows a sensitivity to hydrogen embrittlement. Among duplex stainless steels, the 22 Cr 5 Ni grade has gradually became the most used. In this work the tensile properties and the resistance to fatigue crack propagation of 22 Cr5 Ni duplex stainless steel have been analysed, with and without hydrogen charging, after it had been treated at temperatures ranging between 200-1050 deg. C for varying times. The heat treatment times and temperatures were chosen to characterise completely the effects of the different intermetallic and the carbide and nitride phases and to compare these results with those from the tensile tests and those in the literature. A technique for obtaining the hydrogen diffusion coefficient in the steel was optimised and was shown to be alternative to the permeation technique. Thermal analysis was used to determine the activation energy of the hydrogen traps in the steel. From the results the following conclusions were established: - Grain boundaries and dislocations have very little influence on the process of hydrogen diffusion. - The quantity of hydrogen absorbed depends in that any type of precipitate decrease the absorption. This decrease was probably due to changes in the diffusivity and solubility of hydrogen caused by the precipitation. - The charging with hydrogen caused a large decrease in ε m pc for the steel for all heat treatments temperature, except 1050 deg. C. At this temperature the effect was much less as the dislocation density was very low and the precipitates were now in solution. - Hydrogen charging of the steel did not affect the YS and the decrease in UTS produced depended on the microstructure. Use of the embrittlement index 'F' showed that spinodal decomposition and precipitation of G phase decrease hydrogen embrittlement

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 %.

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.

Forms of Pilgrimage at the Shrine of Khāled Nabi, Northeastern Iran

Directory of Open Access Journals (Sweden)

Mehdi Ebadi

2015-07-01

Full Text Available Pilgrimage (religious tourism is one of the fastest growing forms of tourism. Nevertheless, there is still a gap between abstract theory and empirical research about this form of tourism in the literature. This dearth of tourism studies is even more glaring in the field of Ziyārat or pilgrimage in Islam which in spite of its importance and wide extended practice have been mostly ignored in tourism and geographic literature. The present study features one such area that is (almost unknown within the community of tourism and geography researchers. In Iran, religious pilgrimage has a long tradition. Numerous sacred places with varieties of rituals and traditions, which practice among the pilgrims all around the country, indicate on its antiquity (before Islamic periods. Among the most practiced forms of religious pilgrimage are the visits to several thousands of shrines, which are known in Iran as Ziyāratgah (lit. place of visit or Imāmzādeh. One of these Ziyāratgah is the pre-Islamic shrine of Khāled Nabi (also known as Halat Nabi, which belong to a legendary Christian holy man of the 6th A.D. The shrine lies in the northeastern Iranian province of Golestan, in a region called Turkmen-Sahra. Despite its relative remote setting, every year more than 90,000 travellers do visit this shrine. This article seeks to consider varieties of pilgrimage forms at the shrine. The results of the study shows that the travelers of Khāled Nabi shrine are not homogenous and comprise of different types of visitors. In addition to secular motivations, based on the visitors’ inventives, three zones/forms of pilgrimage, namely, ‘‘religious pilgrims’’, ‘‘cultural pilgrims’’, ‘‘nostalgic pilgrims’’have been recognized.

EBSD study of hydrogen-induced cracking in API-5 L-X46 pipeline steel

International Nuclear Information System (INIS)

Venegas, V.; Caleyo, F.; Gonzalez, J.L.; Baudin, T.; Hallen, J.M.; Penelle, R.

2005-01-01

The spatial distribution of plastic deformation and grain orientation surrounding hydrogen-induced cracks (HIC) is investigated in samples of API-5L-X46 pipeline steel using scanning electron microscopy and electron backscattering diffraction (EBSD). This work shows direct experimental evidence of the influence of microstructure, microtexture and mesotexture on HIC crack path

Application of high strength steel to nuclear reactor containment vessel

International Nuclear Information System (INIS)

Susukida, H.; Sato, M.; Takano, G.; Uebayashi, T.; Yoshida, K.

1976-01-01

Nuclear reactor containment vessels are becoming larger in size with the increase in the power generating capacity of nuclear power plants. For example, a containment vessel for a PWR power plant with an output of 1,000 MWe becomes an extremely large one if it is made of the conventional JIS SGV 49 (ASTM A 516 Gr. 70) steel plates less than 38 mm in thickness. In order to design the steel containment vessel within the conventional dimensional range, therefore, it is necessary to use a high strength steel having a higher tensile strength than SGV 49 steel, good weldability and a higher fracture toughness and moreover, possessing satisfactory properties without undergoing post-weld heat treatment. The authors conducted a series of verification tests on high strength steel developed by modifying the ASTM A 543 Grade B Class 1 steel with a view to adopting it as a material for the nuclear reactor containment vessels. As the result of evaluation of the test results from various angles, we confirmed that the high strength steel is quite suitable for the manufacture of nuclear reactor containment vessels. (auth.)

Manufacturing of ultra-large diameter 20 MnMoNi 5 5 steel forgings for reactor pressure vessels and their properties

International Nuclear Information System (INIS)

Onodera, S.; Kawaguchi, S.; Tsukada, H.; Moritani, H.; Suzuki, K.; Sato, I.

1985-01-01

As the structural material for RPV typical of increased dimensions, as set of ultra-large diameter steel forgings for a PHWR RPV is presented as outlined below. (1) Material designation: 20 MnMoNi 5 5 (similar to SA508, Cl.3) (2) Size of the forgings: flanges, 8.440 mm OD, a weight of 238 tons for shell flange; shells and torus, 7,920 mm OD, with large height, cover dome, 6,800 mm OD in chord and 460 mm thick; blank before formed to dome is ca. 8,000 mm OD. (3) Chemical composition: particular effort was made for minimizing the tramp elements as P, S, As, Sn, Sb, Cu. (4) Manufacturing, key points: steel making - combined refining and degassing in ladle; ingot making - largest size ingots, including 570 ton and 500 ton ingots; forging - special ''outside-the-press'' forging and forming techniques; heat treatment - prevention of H 2 flaking in normalizing and tempering and handling of the extra-large forgings at water quenching. (5) Metallurgical properties: sufficiently uniform carbon distributions in the forgings; a lowest possible content of hydrogen, non-metallic inclusions and oxygen. Mechanical properties: uniformity in tensile and toughness properties; flaws - only limited number of spots of UT indications under 2 mm EFG (EFS). (orig.)

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

On the nature of anomalies in temperature dependence of the OKh18N1OT steel yield strength after thermal cycling in the low temperature range

International Nuclear Information System (INIS)

Medvedev, E.M.; Lavrent'ev, F.F.; Kurmanova, T.N.

1978-01-01

Investigated were structural transformations in 0Kh18N10T steel as a result of heating and cooling and of deformation within the range of temperatures between 300 and 77 K, the quantity relationships between the said transformations and the variation of the yield limit with the temperature. The studies were conducted by metallography and mechanical test methods. It was shown that an increase in the number of heating and cooling cycles correlates with a loss in strength of the steel while deformation at 77 K. This anomaly in the temperature relationship of the yield limit is related to the appearance in the course of deformation of α-martensite with a BCC lattice. Deformation at 300 K increases the amount ea of epsilon-martensite, a decrses the effectve size of grain and, in consequence, increases the yield limit. The relationship between the yield limit and the grain size at the temperature of 300 K is described adequately by the Hall-Petch equation

The influence of surface roughness on the hydrogen permeation of type API 5L-X52 steel

International Nuclear Information System (INIS)

Requiz, R.; Vera, N.; Camero, S.

2004-01-01

The influence of surface roughness on the corrosion and hydrogen permeation behaviour was evaluated on a type API 5L-52 steel in dearated 0.1M NaSO 4 at pH=2. Potentiodynamic polarization curves were employed to determine the electrochemical behaviour of the steel, while the Devanathan-Stachurski technique was used to estimate the hydrogen permeation rate. Additionally, the surface roughness profiles were obtained in order to correlate the changes in the hydrogen perkeation rate with different metal surface finishings. The obtained results clearly demonstrate that when the roughness parameters have larger values, the cathodic current of hydrogen evolution increases while the hydrogen entry rate decreases. This effect can be attributed to the microstructural defects induced at the steel surface, such as dislocations, which increase the catalytic activity of the atomic hydrogen favouring its recombination. Also, these defects could allow the atomic hydrogen to remain adsorbed on the steel surface. Both effects could hinder the hydrogen diffusion into the metal since the possibility for this atom of becoming absorbed has been reduced. (Author) 16 refs

High yttria ferritic ODS steels through powder forging

Energy Technology Data Exchange (ETDEWEB)

Kumar, Deepak [Department of Metallurgical and Materials Engineering, I.I.T-Roorkee, Uttarakhand 247667 (India); Prakash, Ujjwal, E-mail: ujwalfmt@iitr.ac.in [Department of Metallurgical and Materials Engineering, I.I.T-Roorkee, Uttarakhand 247667 (India); Dabhade, Vikram V. [Department of Metallurgical and Materials Engineering, I.I.T-Roorkee, Uttarakhand 247667 (India); Laha, K.; Sakthivel, T. [Mechanical Metallurgy Group, IGCAR, Kalpakkam, Tamilnadu 603102 (India)

2017-05-15

Oxide dispersion strengthened (ODS) steels are being developed for future nuclear reactors. ODS Fe-18%Cr-2%W-0.2%Ti steels with 0, 0.35, 0.5, 1 and 1.5% Y{sub 2}O{sub 3} (all compositions in weight%) dispersion were fabricated by mechanical alloying of elemental powders. The powders were placed in a mild steel can and forged in a stream of hydrogen gas at 1473 K. The steels were forged again to final density. The strength of ODS steel increased with yttria content. Though this was accompanied by a decrease in tensile elongation, all the steels showed significant ductility. The ductility in high yttria alloys may be attributed to improved inter-particle bonding between milled powders due to reduction of surface oxides by hydrogen. This may permit development of ODS steels with yttria contents higher than the conventional limit of 0.5%. It is suggested that powder forging is a promising route to fabricate ODS steels with high yttria contents and improved ductility. - Highlights: •ODS steels with yttria contents beyond the conventional limit of 0.5 wt% were fabricated by powder forging in a hydrogen atmosphere. •All the alloys exhibited significant ductility. •This may be attributed to improved inter-particle bonding due to reduction of surface oxides by hydrogen. •Strength in excess of 300 MPa was obtained at 973 K for 0.5%, 1% and 1.5% yttria ODS alloys. •Powder forging is a promising route to fabricate ODS steels and permits development of compositions with up to 1.5% yttria.

Biological Background of Kh.DIC Mice and Their Learning and Memory Defects

Institute of Scientific and Technical Information of China (English)

潘卫松; 邢东明; 秦川; 孙虹; 高虹; 金文; 杜力军

2003-01-01

The learning ability of the Kh.DIC mice, a mutant of the Kunming mice, was studied to analyze its memory development.The mice's brain function was evaluated using a water maze with the amount of monoamines measured by fluorospectrophotometry and enzyme activities detected by ultraviolet spectrophotometry.The mice were found to have spacial learning and memory defects at the age of 1 month in both ordinary animals and in special pathogen free (SPF) animals.At the same time, the amount of monoamines and the activities of monoamine oxidase-B and dopamine-β-hydroxylase differed from those of the Kunming mice.The defects might be related to the differences in the monoamine neurotransmitter system.The results suggest that the DIC mice may be useful economic animal models for the study of brain defects.

Evaluation of Flash Bainite in 4130 Steel

Science.gov (United States)

2011-07-01

Technical Report ARWSB-TR-11011 Evaluation of Flash Bainite in 4130 Steel G. Vigilante M. Hespos S. Bartolucci...4. TITLE AND SUBTITLE Evaluation of Flash Bainite in 4130 Steel 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...need to be addressed, the Flash Bainite processing of 4130 steel demonstrates promise for applications needing a combination of high strength with

The effects of N+ implantation on the wear and friction of type 304 and 15-5 PH stainless steels

International Nuclear Information System (INIS)

Yost, F.G.; Picraux, S.T.; Follstaedt, D.M.; Pope, L.E.; Knapp, J.A.

1983-01-01

Ion implantation of N + into mechanically polished type 304 and 15-5 PH stainless steels was studied to determine its effect on dry wear and friction behavior. Implantation of 4.0 X 10 17 N + cm -2 at 50 keV yielded a depth profile with a peak concentration of about 45 at.% at a depth of 70 nm which dropped to about 10 at.% at 120 nm. Wear and friction were studied in an unlubricated pin-on-disc configuration using type 304 and 440C stainless steel pins. Both N + -implanted steels exhibited reduced wear at low loads but no significant reduction in the coefficient of friction was found. At the lowest normal load studied (12.3 gf), the average maximum wear depth of the implanted 15-5 PH stainless steel disc (about 0.1 μm) was reduced to approximately 10% of that for the corresponding unimplanted pin-on-disc pair after 1000 cycles. At normal loads of 50 gf or above (corresponding to hertzian stresses of 1160 MPa or higher) all beneficial effects were gone. Vacuum heat treatment at 923 K for 1.8 ks of an identically implanted type 304 stainless steel specimen eradicated the beneficial effects of the nitrogen implantation. The N + -implanted discs show similar reductions in wear to discs implanted with titanium and carbon, but the N + -implanted discs do not exhibit the reductions in the coefficient of friction seen with the discs implanted with titanium and carbon. (Auth.)

Characterization of Mechanical Properties and Residual Stress in API 5L X80 Steel Welded Joints

Science.gov (United States)

de Sousa Lins, Amilton; de Souza, Luís Felipe Guimarães; Fonseca, Maria Cindra

2018-01-01

The use of high-strength and low-alloy steels, high design factors and increasingly stringent safety requirements have increased the operating pressure levels and, consequently, the need for further studies to avoid and prevent premature pipe failure. To evaluate the possibility of improving productivity in manual arc welding of this type of steel, this work characterizes the mechanical properties and residual stresses in API 5L X80 steel welded joints using the SMAW and FCAW processes. The residual stresses were analyzed using x-ray diffraction with the sin2 ψ method at the top and root of the welded joints in the longitudinal and transverse directions of the weld bead. The mechanical properties of the welded joints by both processes were characterized in terms of tensile strength, impact toughness and Vickers microhardness in the welded and shot peening conditions. A predominantly compressive residual stress was found, and shot peening increased the tensile strength and impact toughness in both welded joints.

38 CFR 8.5 - Authorization for deduction of premiums from compensation, retirement pay, or pension.

Science.gov (United States)

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Authorization for deduction of premiums from compensation, retirement pay, or pension. 8.5 Section 8.5 Pensions, Bonuses, and... Authorization for deduction of premiums from compensation, retirement pay, or pension. Deductions from benefits...

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

International Nuclear Information System (INIS)

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

1984-01-01

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

Wear-resistance investigation of electro-screen coatings obtained using electroerosive powders of micro and nanofractions

Science.gov (United States)

Ageev, E. V.; Altukhov, A. Yu; Malneva, Yu V.; Novikov, A. N.

2018-03-01

The results of the wear resistance investigation of electro sparking coatings, applied using electrode material from electroerosive powders of hard alloy VK-8 (90%) with the addition of powder of high-speed steel of grade R6M5 (10%), are presented. Electro spark coatings were formed on samples of 30KhGSA steel using these electrodes and installation UR-121. The coefficient of friction and the wear rate of the surface of the sample and counterbody were measured on an automated friction machine “Tribometer” (CSM Instruments, Switzerland), controlled by a computer, according to the standard “ball-disk” test scheme.

Microstructural influence on the local behaviour of 16MND5 steel

International Nuclear Information System (INIS)

Sekfali, S.

2004-06-01

16MND5 Steel or A508 Cl3 is used for manufacture by forging of nuclear reactor vessels. This material presents a good compromise in term of tenacity and yield stress, its microstructure is mainly bainitic tempered. Because of the chemical composition local variation and process of development, this material presents microstructural heterogeneities which can locally modify the properties of damage. In particular, some zones present a martensitic microstructure. The goal of this thesis is to bring some explanations on the influence of the microstructure; more particularly, size of the crystallographic entities and their spatial distribution on the local behaviour of 16MND5 steel. Two microstructures were elaborated for this purpose, a tempered bainitic microstructure and a tempered martensitic microstructure. An experimental characterization was carried out on the two microstructures in order to determine morphology, spatial distribution of the crystallographic orientations and tensile behaviour. A deposit of micro grid was carried out on tensile specimens to determine the experimental deformation field on a beforehand EBSD analyzed zone. The determination of the tensile behaviour allowed the identification of a multi crystalline behaviour law by a reverse method using the density of dislocation on each system of slip. This behaviour law was used in simulations with a finite element method to simulate the local mechanical field of the two microstructures and to compare with the obtained experimental deformation fields. It results, a good adequacy between simulations and experiments and the description of the influence of the neighbor grain's orientation on the local behaviour. (author)

Microstructure-strength relations in a hardenable stainless steel with 16 pct Cr, 1.5 pct Mo, and 5 pct Ni

Science.gov (United States)

Grobner, P. J.; Blšs, V.

1984-07-01

Metallographic studies have been conducted on a 0.024 pct C-16 pct Cr-1.5 pct Mo-5 pct Ni stainless steel to study the phase reactions associated with heat treatments and investigate the strengthening mechanisms of the steel. In the normalized condition, air cooled from 1010 °C, the microstructure consists of 20 pct ferrite and 80 pct martensite. Tempering in a temperature range between 500 and 600 °C results in a gradual transformation of martensite to a fine mixture of ferrite and austenite. At higher tempering temperatures, between 600 and 800 °C, progressively larger quantities of austenite form and are converted during cooling to proportionally increasing amounts of fresh martensite. The amount of retained austenite in the microstructure is reduced to zero at 800 °C, and the microstructure contains 65 pct re-formed martensite and 35 pct total ferrite. Chromium rich M23C6 carbides precipitate in the single tempered microstructures. The principal strengthening is produced by the presence of martensite in the microstructure. Additional strengthening is provided by a second tempering treatment at 400 °C due to the precipitation of ultrafine (Cr, Mo) (C,N) particles in the ferrite.

The History Of Muhammadiyahs Thought And Movement Study On Personality And Idea Of The Founding Figure KH. Ahmad Dahlan

Directory of Open Access Journals (Sweden)

Fauji Koda

2017-08-01

Full Text Available Muhammadiyah is one of the pioneers of religious renewal in Indonesia. As a religious reformist Muhammadiyah has contributed greatly in the development of the majority of Indonesias people are Muslims. This research is a study of the thought and movement of Muhammadiyah in Indonesia aims to conduct a study in order to understand the history and ideas of the Muhammadiyah movement focused on the personality of the founder KH. Ahmad Dahlan and the idea of social renewal Muhammadiyah movement. Study of this scientific work using qualitative paradigm with historical-phenomenological approach which examines the history and phenomenon of Muhammadiyah from aspects of personality and thoughts and ideas of KH. Ahmad Dahlan revealed in external actions words and deeds in developing Muhammadiyah in Indonesia. The results of this study indicate that the birth of Muhammadiyah in Indonesia is strongly influenced by the Islamic reform movement in the world the basic idea of thinking founder of Muhammadiyah is the unity of humanity which has implications for the doctrine to achieve welfare and peace of all mankind the idea of social reform Muahmmadiyah refers to movement Tajdid which includes purification and renewal modernization.

Redemption of asthma pharmaceuticals among stainless steel and mild steel welders

DEFF Research Database (Denmark)

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

2015-01-01

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

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.

Analysis of Organic Samples from the 5-H and 3-F Pump Tanks and Waste Tank 38H

International Nuclear Information System (INIS)

Swingle, R.F. II

1999-01-01

Analyses for organic materials in aqueous and surface floating samples taken from the 5-H Pump Tank and Waste Tank 38H and in vapor samples taken from the 5-H and 3-F Pump Tanks have been completed. The results indicate that the concentration of organic materials is extremely low in all samples. This report documents the development of sampling and analysis techniques for this sampling as well as the results of the analyses of vapor samples pulled from Pump Tanks 5-H and 3-F and liquid samples pulled from Waste Tank 38H and Pump Tank 5-H

High yttria ferritic ODS steels through powder forging

Science.gov (United States)

Kumar, Deepak; Prakash, Ujjwal; Dabhade, Vikram V.; Laha, K.; Sakthivel, T.

2017-05-01

Oxide dispersion strengthened (ODS) steels are being developed for future nuclear reactors. ODS Fe-18%Cr-2%W-0.2%Ti steels with 0, 0.35, 0.5, 1 and 1.5% Y2O3 (all compositions in weight%) dispersion were fabricated by mechanical alloying of elemental powders. The powders were placed in a mild steel can and forged in a stream of hydrogen gas at 1473 K. The steels were forged again to final density. The strength of ODS steel increased with yttria content. Though this was accompanied by a decrease in tensile elongation, all the steels showed significant ductility. The ductility in high yttria alloys may be attributed to improved inter-particle bonding between milled powders due to reduction of surface oxides by hydrogen. This may permit development of ODS steels with yttria contents higher than the conventional limit of 0.5%. It is suggested that powder forging is a promising route to fabricate ODS steels with high yttria contents and improved ductility.

Stereofractographic investigation of static start and dynamic jump of a fatigue crack in pressure vessel steel

International Nuclear Information System (INIS)

Stepanenko, V.A.; Shtukaturova, A.S.; Yasnij, P.V.; AN Ukrainskoj SSR, Kiev. Inst. Problem Prochnosti)

1983-01-01

Results of investigaytion have been discussed ipto the effect of certain temperature-force factors on regularities in the formation of stretch zones during the crack initiation static and transition zones at crack jumps in the process of cyclic loading. The 15Kh2NMFA pressure vessel steel has been investigated. The steel fracture toughnesKub(Ic) has been determined testing s the specimens for excentric stretching or a bending through an angle. It has been shown that transition zones in a front of fatique cracks at the jump beginning and end are formed through the shift mechanism owing to the material separation along the maximum failure zone contour, i.e. along the plastic zone contour in a crack vertex. This is the mait difference of regularities in the formation of the transition zones during fatique crack jumps from stretching zones formed through the break-away mechanism of crack vertex bluntness during its static move. It is noted that a final conclusion on the mechanism of transition zone formation during fartique crack jumps allows one to perform systematic investigation into the plastic zone configuration in a fatique crack verteX and stereofractographic measurement of two identically conjugate jump surfaces on opposite fractures of the same samples

Microstructural characterisation and corrosion performance of old railway girder bridge steel and modern weathering structural steel

International Nuclear Information System (INIS)

Tewary, N.K.; Kundu, A.; Nandi, R.; Saha, J.K.; Ghosh, S.K.

2016-01-01

Highlights: • Microstructure and corrosion performance are compared for two structural steels. • Microstructure evolution shows primarily ferrite-pearlite in both the steels. • Steels show higher corrosion rate in 1% HCl solution than in 3.5% NaCl solution. • The corrosion products show the presence of oxide, hydroxide and oxy-hydroxides. • The corroded surface reveals morphologies like flowery, cotton balls and rosette. - Abstract: A comparison on microstructure and corrosion performance has been made between the two structural steels used in old railway girder bridge (Sample A) and modern grades of weathering structural steel (Sample B). The microstructures, viewed under optical microscope and scanning electron microscope (SEM), show mainly ferrite-pearlite phase constituents in both the steels, A and B. The phase fraction analysis shows higher amount of pearlite in steel A compared to that of steel B. The grain size of steel A is larger than that of steel B under identical processing condition. The immersion corrosion test in 3.5% NaCl shows that the corrosion rate of steel A increases with time, while the same for steel B decreases with time. On the other hand, corrosion test in 1% HCl shows that the corrosion rate of both steel A and B is higher as compared to that of NaCl which always decreases with time. The XRD analysis of corrosion products show the presence of many oxides, hydroxide and oxy-hydroxide like Lepidocrocite (γ-FeOOH), Goethite (α-FeOOH), Akaganeite (β-FeOOH), Magnetite (Fe_3O_4) and Maghemite (γ-Fe_2O_3) in both the steels. The SEM images of corroded surfaces reveal different morphologies like flowery, cotton balls and rosette etc. which indicate that the corrosion products primarily contain Lepidocrocite (γ-FeOOH), Goethite (α-FeOOH) and Akaganeite (β-FeOOH).

Corrosion of radioactive waste containers, case of a container made of low allow steel

International Nuclear Information System (INIS)

Bataillon, C.; Musy, C.; Roy, M.

2001-01-01

The following topics were dealt with: radioactive waste concept ANDRA, low alloy steel (XC38) container corrosion under representative storage conditions, corrosion rate and passivation effects, micrographic investigations

New 1H-pyrrole-2,5-dione derivatives as efficient organic inhibitors of carbon steel corrosion in hydrochloric acid medium: Electrochemical, XPS and DFT studies

International Nuclear Information System (INIS)

Zarrouk, A.; Hammouti, B.; Lakhlifi, T.; Traisnel, M.; Vezin, H.; Bentiss, F.

2015-01-01

Highlights: • 1H-pyrrole derivatives act as good corrosion inhibitors for carbon steel in 1 M HCl. • Adsorption of the inhibitors on carbon steel surface obeys Langmuir’s isotherm. • XPS showed that the inhibitors are chemisorbed on the metal surface. • Quantum chemical parameters were correlated with experimental results. - Abstract: New 1H-pyrrole-2,5-dione derivatives, namely 1-phenyl-1H-pyrrole-2,5-dione (PPD) and 1-(4-methylphenyl)-1H-pyrrole-2,5-dione (MPPD) were synthesised and their inhibitive action against the corrosion of carbon steel in 1 M HCl solution were investigated at 308 K by weight loss, potentiodynamic polarization curves, and electrochemical impedance spectroscopy (EIS) methods. The results showed that the investigated 1H-pyrrole-2,5-dione derivatives are good corrosion inhibitors for carbon steel in 1 M HCl medium, their inhibition efficiency increased with inhibitor concentration, and MPPD is slightly more effective than PPD. Potentiostatic polarization study showed that PPD and MPPD are mixed-type inhibitors in 1 M HCl. Impedance experimental data revealed a frequency distribution of the capacitance, simulated as constant phase element. The results obtained from electrochemical and weight loss studies were in reasonable agreement. The adsorption of MPPD and PPD on steel surface obeyed Langmuir’s adsorption isotherm. Thermodynamic data and XPS analysis clearly indicated that the adsorption mechanism of 1H-pyrrole-2,5-dione derivatives on carbon steel surface in 1 M HCl solution is mainly controlled by a chemisorption process. Quantum chemical calculations using the Density Functional Theory (DFT) were performed on 1H-pyrrole-2,5-dione derivatives to determine the relationship between molecular structures and their inhibition efficiencies

The influence of remelting parameters of the electric arc and conventional tempering on the tribological resistance of high speed steel HS 6-5-2

Directory of Open Access Journals (Sweden)

A. Dziedzic

2011-07-01

Full Text Available The present thesis depicts the results of the research of tribological high speed steel HS 6-5-2 remelted with the electric arc. Steel was remelted with different parameters. The amperage of electric arc was changed, the scanning speed was changed and the single, overlapping remeltings were used. There was also the influence of conventional tempering defined, which was conducted after remelting on the tribological resistance of hardened steel. For the previously mentioned processing variants, the intensity of tribological wear was defined and the linear wear were presented, and the friction coefficients. The type of tribological wear was also given, present during the friction, technically dry, of the hardened steel. The lower intensity of tribological wear was received for the single remelting by electric arc of 50 and 70A. Using the overlapping remeltings for the strengening of the surface layer of the high speed steel HS 6-5-2 causes the increase of the intensity of tribological wear in comparison to the steel with the single remelting. The conventional tempering leads to the decrease of the intensity of tribological wear.

Development of ferritic steels for fusion reactor applications

Energy Technology Data Exchange (ETDEWEB)

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

1988-08-01

Chromium-molybdenum ferritic (martensitic) steels are leading candidates for the structural components for future fusion reactors. However, irradiation of such steels in a fusion environment will produce long-lived radioactive isotopes that will lead to difficult waste-disposal problems. Such problems could be reduced by replacing the elements in the steels (i.e., Mo, Nb, Ni, N, and Cu) that lead to long-lived radioactive isotopes. We have proposed the development of ferritic steels analogous to conventional Cr-Mo steels, which contain molybdenum and niobium. It is proposed that molybdenum be replaced by tungsten and niobium be replaced by tantalum. Eight experimental steels were produced. Chromium concentrations of 2.25, 5, 9, and 12% were used (all concentrations are in wt %). Steels with these chromium compositions, each containing 2% W and 0.25% V, were produced. To determine the effect of tungsten and vanadium, 2.25 Cr steels were produced with 2% W and no vanadium and with 0.25% V and O and 1% W. A 9Cr steel containing 2% W, 0.25 V, and 0.07% Ta was also studied. For all alloys, carbon was maintained at 0.1%. Tempering studies on the normalized steels indicated that the tempering behavior of the new Cr-W steels was similar to that of the analogous Cr-Mo steels. Microscopy studies indicated that 2% tungsten was required in the 2.25 Cr steels to produce 100% bainite in 15.9-mm-thick plate during normalization. The 5Cr and 9Cr steels were 100% martensite, but the 12 Cr steel contained about 75% martensite with the balance delta-ferrite. 33 refs., 35 figs., 5 tabs.

Development of ferritic steels for fusion reactor applications

International Nuclear Information System (INIS)

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

1988-08-01

Chromium-molybdenum ferritic (martensitic) steels are leading candidates for the structural components for future fusion reactors. However, irradiation of such steels in a fusion environment will produce long-lived radioactive isotopes that will lead to difficult waste-disposal problems. Such problems could be reduced by replacing the elements in the steels (i.e., Mo, Nb, Ni, N, and Cu) that lead to long-lived radioactive isotopes. We have proposed the development of ferritic steels analogous to conventional Cr-Mo steels, which contain molybdenum and niobium. It is proposed that molybdenum be replaced by tungsten and niobium be replaced by tantalum. Eight experimental steels were produced. Chromium concentrations of 2.25, 5, 9, and 12% were used (all concentrations are in wt %). Steels with these chromium compositions, each containing 2% W and 0.25% V, were produced. To determine the effect of tungsten and vanadium, 2.25 Cr steels were produced with 2% W and no vanadium and with 0.25% V and O and 1% W. A 9Cr steel containing 2% W, 0.25 V, and 0.07% Ta was also studied. For all alloys, carbon was maintained at 0.1%. Tempering studies on the normalized steels indicated that the tempering behavior of the new Cr-W steels was similar to that of the analogous Cr-Mo steels. Microscopy studies indicated that 2% tungsten was required in the 2.25 Cr steels to produce 100% bainite in 15.9-mm-thick plate during normalization. The 5Cr and 9Cr steels were 100% martensite, but the 12 Cr steel contained about 75% martensite with the balance delta-ferrite. 33 refs., 35 figs., 5 tabs

TiC reinforced cast Cr steels

Energy Technology Data Exchange (ETDEWEB)

Dogan, O.N.; Hawk, J.A.; Schrems, K.K.

2006-06-01

A new class of materials, namely TiC-reinforced cast chromium (Cr) steels, was developed for applications requiring high abrasion resistance and good fracture toughness. The research approach was to modify the carbide structure of commercial AISI 440C steel for better fracture resistance while maintaining the already high abrasion resistance. The new alloys contained 12Cr, 2.5–4.5Ti, and 1–1.5C (wt.%) and were melted in a vacuum induction furnace. Their microstructure was composed primarily of a martensitic matrix with a dispersion of TiC precipitates. Modification of TiC morphology was accomplished through changing the cooling rate during solidification. Wear rates of the TiC-reinforced Cr steels were comparable to that of AISI 440C steel, but the impact resistance was much improved.

TiC-reinforced cast Cr steels

Science.gov (United States)

Doğan, Ö. N.; Hawk, J. A.; Schrems, K. K.

2006-06-01

A new class of materials, namely TiC-reinforced cast chromium (Cr) steels, was developed for applications requiring high abrasion resistance and good fracture toughness. The research approach was to modify the carbide structure of commercial AISI 440C steel for better fracture resistance while maintaining the already high abrasion resistance. The new alloys contained 12Cr, 2.5-4.5Ti, and 1-1.5C (wt.%) and were melted in a vacuum induction furnace. Their microstructure was composed primarily of a martensitic matrix with a dispersion of TiC precipitates. Modification of TiC morphology was accomplished through changing the cooling rate during solidification. Wear rates of the TiC-reinforced Cr steels were comparable to that of AISI 440C steel, but the impact resistance was much improved.

Weldability of Stainless Steels

International Nuclear Information System (INIS)

Saida, Kazuyoshi

2010-01-01

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

Estimation of CO2 emission for each process in the Japanese steel industry: a process analysis

International Nuclear Information System (INIS)

Sakamoto, Y.; Tonooka, Y.

2000-01-01

The CO 2 emission for each process in the Japanese steel industry is estimated by a process analysis using statistical data in order to evaluate the possibility of reducing CO 2 emissions. The emission factor of CO 2 for each product and also for crude steel produced from an integrated steel plant route and an electric arc furnaces route is estimated and compared. The CO 2 emissions can be estimated from production amounts of products for each process and for crude steel. The CO 2 emission of blast furnaces is the largest and that of rolling and piping follows. The emission factor of CO 2 of crude steel produced from an integrated steel plant route is approximately 3.8 times as high as that produced via an electric arc furnace route. (Author)

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

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

Effect of Deoxidation Process on Inclusion and Fatigue Performance of Spring Steel for Automobile Suspension

Science.gov (United States)

Hu, Yang; Chen, Weiqing; Wan, Changjie; Wang, Fangjun; Han, Huaibin

2018-04-01

55SiCrA spring steel was smelted in a vacuum induction levitation furnace. The liquid steel was treated by Si deoxidation, Al modification with Ca treatment and Al modification, and the steel samples were obtained with deformable Al2O3-SiO2-CaO-MgO inclusions closely contacted with steel matrix, Al2O3-CaO-CaS-SiO2-MgO inclusions surrounded by small voids or Al2O3(> 80 pct)-SiO2-CaO-MgO inclusions surrounded by big voids, respectively. Effect of three types of inclusions on steel fatigue cracks was studied. The perpendicular and transverse fatigue cracks around the three types of inclusions leading to fracture were found to vary in behavior. Under the applied stress amplitude of 775 MPa, the fatigue lives of the three spring steels decreased from 4.0 × 107 to 3.8 × 107, and to 3.1 × 107 cycles. For the applied stress amplitude of 750 MPa, the fatigue lives of the three spring steels decreased from 5.2 × 107 to 4.1 × 107, and to 3.4 × 107 cycles. Based on the voids around inclusions, the equivalent size of initial fatigue crack has been newly defined as √ {{{area}_{inclusion} }/{(1 - {CC)}}} , where the contraction coefficient CC of inclusion was introduced. A reliable forecast model of the critical size of inclusion leading to fracture was established by the incorporation of actual width b inclusion or diameter d inclusion of internal inclusion; the model prediction was found to be in agreement with experimental results.