Effect of the heat-treatment regime and carbon content on the damping properties of steel 01Kh6F2

The high damping properties of ferrite chromium steels caused by magnetoelastic hysteresis depend substantially on the defects of the crystal structure. For this reason the regimes of mechanical and heat treatment can change their damping level by more than a factor of 10. Elimination of thermal stresses and deformations in parts, prevention of formation of carbides, intermetallic compounds or chemical inhomogeneities in the structure of steels, and the reduction of the specific surface of the boundaries are known, but still insufficiently studied, ways of attaining a highly damped state in steels and alloys. The present work concerns the effect of the mentioned factors and some others on the damping properties of a ferrite steel of grade 01 Kh6F2. Another object of study is the effect of a variable magnetic field on the damping and the defect of the shear modulus. The results obtained are analyzed to interpret the regular features established. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 12, pp. 6–9, December, 1997.     

Embrittlement of ferritic chrome steels in welding

Conclusions High-temperature heating characteristic of a weld joint in the area of overheating of the heat-affected zone causes an increase in the parameters and the static distortions of the crystalline lattice of chrome steels with an increase in nitrogen content. At the same time, the inelastic effects, the Snoek and Kester peaks, increase, which is caused by the introduction of nitrogen into the crystalline lattice and its interaction with the fields of stresses and dislocations.After imitation of the structure of overheating steels contaminated with nitrogen have a high impact strength, which is an indication of the weak influence of supersaturation of the crystalline lattice on the tendency of chrome steels toward embrittlement in welding.An increase in the carbon content has a negative influence on the impact strength of chrome steels after high-temperature welding heating. In comparison with steels contaminated with nitrogen there is practically no increase in the lattice parameters of such steels. After high-temperature heating the static distortions of the lattice decrease. There is also a decrease in the peaks of internal friction caused by migration of carbon atoms along the interstices of the crystalline lattice into the zones of stresses and their interaction with the dislocations.Embrittlement of ferritic chrome steels as the result of carbide precipitates is also possible after short-time heating in the 550–850°C range, which is indicated by the decrease in the crystalline lattice parameters and also the maximum in internal friction caused by carbon atoms. In heating to 400–550°C nitrides are also formed together with carbides.The effects revealed after short-time heating make it possible to relate the mechanism of embrittlement of ferritic chrome steels in welding to strengthening of the heat-affected zone metal as the result of precipitates of finely dispersed carbonitrides.Central Scientific-Research Institute for Machine Building Technology Scientific Production Association. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 1, pp. 41–45, January, 1984.     

Effectiveness of thermal shotblasting for casehardened steels

The shotpeening process that is used in industry has an ambiguous influence on the contact surface fatigue life of the casehardened steels: it improves this characteristic of the steels 12Kh2N4A and 12Kh2NVFA when using the rational hardening regime and reduces the contact surface fatigue life for any regimes of shotpeening of the temperature-resistant steel 16Kh3NVFMB-Sh. Low-temperature post-deformation annealing improves the contact surface fatigue life of both steels, but it limits their operating temperature. We can broaden the operating temperature range by the use of thermal shotblasting, which involves strain hardening of the casehardened surface that is heated to 250 °C. This is shown in the present work.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 5, pp. 21–24, May, 1994.     

Structure and properties of 4Kh3VMFS and 3Kh3VMF heat-resistant die steels

Conclusion The austenitic grain growth of types 4Kh4VMFS and 3Kh3VMF hot work die steels in heating may be caused by solution of carbides, migration of boundaries, or "scattering" of them, which determines the optimum hardening temperature of these steels, 1120–1140°C for 4Kh3VMFS and 1060–1080°C for 3Kh3VMF, respectively. The combination of properties of the new steels significantly exceeds that of the standard.The Ukrainian Scientific-Research Institute for Special Steel. Translated from Metallovdenie i Termicheskaya Obrabotka Metallov, No. 11, pp. 38–41, November, 1985.     

Features of thermal fatigue failure for die steels 3Kh2V8F and 4Kh5MFS under injection mold operating conditions

Extensive use of die casting is limited by the short operating life of molds with cyclically changing temperature and stresses. As a result of this action there is thermal fatigue failure of the operating surface layer of a mold. This article considers features of the thermal fatigue failure mechanism for steels 3Kh2V8F and 4Kh5MFS used for mold manufacture.Rybinsk Aviation Technology Institute. Translated from Metailovedenie i Termicheskaya Obrabotka Metallov, No. 4, pp. 34–37, April, 1994.     

Effect of Overheating on the Mechanical Properties of Roll-Foundry and Die Steels

The effect of overheating on the properties and structure of roll steels 9Kh2, 9Kh2MF, and 9Kh2SVF and steel 5KhNV used for the production of heavy-duty forging dies is studied. It is shown that the elevation of the heating temperature changes the fracture behavior of roll steels. The temperature of overheating of roll steels is established. It is shown that the consequences of the overheating can be removed by means of subsequent quenching from conventional temperatures (860 – 890°C). The overheating is shown to have a weak effect on the properties of steel 5KhNV, which can be removed by single heating to a temperature of 890°C.     

Temperature interval of the effective action of the magnetic field during the thermomagnetic treatment of iron-chromium-cobalt alloys

Conclusions When magnetically hard iron—chromium—cobalt alloys Kh23K15YuB and Kh23K15YuBF are subjected to thermomagnetic treatment using steady cooling in a magnetic field, the effective action of the latter is manifested in the 670–640°C interval.Novocherkassk Scientific-Research Institute of Permanent Magnets. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 50–51, July, 1981.     

Structure and Properties of Nitrocarburized Steels 4Kh5MFS and 20Kh13 Used for Manufacturing Cutting Tools

Special features of structure formation in diffusion layers on steels 4Kh5MFS and 20Kh13 during nitrocarburizing at 940 – 990°C in charcoal granulated mixtures enriched with carbamide and sodium carbonate are studied. The conditions for manufacturing wear-resistant tools from the studied steels are determined.     

Structural-Phase Condition and Wear Resistance of Gasothermal Coatings from High-Chromium Steels Modified with Nitrogen Ions and Sprayed with the use of High-Enthalpy Combustible Gas

Metal Science and Heat Treatment - The structural and phase condition, microhardness and wear resistance of nitrided high-chromium wire steels 40Kh13, 40Kh17M, 02Kh17N11M2 and gasothermal coatings...     

High-temperature nitriding of chromium and chromium-nickel steels

Conclusions High-temperature nitriding accelerates the diffusion of nitrogen in steel. Nitriding at 700° for 3 h resulted in a case depth of 0.20–0.27 mm with HV 750–1000 for ferritic steels 0Kh13 and Kh16, and a case depth of 0.09 mm with HV 950 for austenitic steel Kh18N9T.Moscow Highway Institute. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 19–22, February, 1971.     

Nitriding of die steels 4Kh5MFS and 5Kh2MNF in a vibrofluidized bed

Conclusions Nitriding of steels 4Kh5MFS and 5Kh2MNF in a vibrofluidized bed (graphite with a particle size of 0.2–0.4 mm) should be conducted at 540–570° with the ammonia entering below the bed at a rate of 1.1 liter/min, frequency of vibration 22 Hz, amplitude of vibration 2.0 mm, and acceleration of vibration 4g. After 5 h the case depth is 0.25 mm for steel 4Kh5MFS and 0.22 mm for steel 5Kh2MNF.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 11, pp. 57–58, November, 1978.     

Use of damping materials for increasing the quality and service properties of parts

Conclusion Type 04Kh11Yu chromium-aluminum steels are promising high-damping materials. They contain readily available alloy elements and are more corrosion- and scale-resistant than such high-damping alloys as magnesium and manganese-copper alloys and cast irons. In addition, they are more easily melted and hot worked by pressure than magnesium and manganese-copper alloys. Heat treatment of chromium-aluminum steels for high damping is simple.Broader use in industry of increased damping capacity type 120S2YuD graphitic steels is desirable. They are hardened significantly by heat treatment, are relatively inexpensive, and have recommended themselves positively during experimental production tests on reduction of the noise of mechanisms with gear drives. The use of them in place of 40Kh and 30KhGSA steels causes a reduction in noise of mechanisms with gear drives of 6 db. In addition, the wear resistance of the gears increases.Kirov Polytechnic Institute. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 12, pp. 3–4, December, 1987.     

Effect of HTMT on the thermal fatigue resistance of die steels

Conclusions HTMT increases the thermal fatigue resistance of steel 4Kh4MVFS with cyclic heating to 650°. The rate of crack growth slows down and the number of cycles to appearance of the first crack remains unchanged. The thermal fatigue resistance of steels 5KhNV and 4Kh5MFS does not change with thermal cycling to 500 and 550° after HTMT, but decreases with thermal cycling at higher temperatures.Chelyabinsk Polytechnic Institute. Chelyabinsk Metallurgical Factory. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 3, pp. 29–31, March, 1979.     

Structure and properties of diffusion layers formed in vacuum cyanidation of steel 20Kh13 in an atmosphere of pyrolysis of liquid hydrocarbons

The use of carburized high-chromium steels with 13–18% Cr for the production of wear-resistant shaping tools and attachments is advantageous for many branches of industry. At the same time, the deposition of carbide diffusion layers on corrosion-resistant high-chromium steels has some special features and technological difficulties, specifically, in quenching, tempering, and polishing of parts and tools. The results described in the present paper and the developed technology of vacuum chemical heat treatment (VCHT), namely, cyanidation of steel 20Kh13 in an active carburizer based on ethanolamines, are of interest for the production of small-size tools and attachments in tool shops of enterprises producing instruments, electronics, watches and clocks, etc. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 10, pp. 26–29, October, 1998.     

Improving the stability of a cold-worked tool

Conclusions The recommended heat-treatment regime—quenching in the melt of a salt mixture and tempering at 380–400°C for 2 h—tends to produce an optimal combination of hardness, strength, and ductility, and ensures higher operational stability of punches formed from steels Kh12M and Kh12F1 as compared with those treated in accordance with the technology of series production. The annual saving generated from the implementation of this heat treatment is 12,000 rubles.Klimovsk Machine-Building Plant. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 8, pp. 24–26, August, 1991.     

Effect of heat treatment on corrosion cracking of high-strength steels

Conclusion The susceptibility of steel to corrosion cracking depends to a large extent on the tempering temperature. With increasing tempering temperatures the susceptibility of oil-quenched steels decreases. At the tempering temperature at which preferential martensite decomposition occurs in former austenite grain boundaries one observes an increase of the susceptibility to corrosion cracking. For steels 30Kh-GSA, 30KhGSNA, and 25Kh2GNTA this increased susceptibility occurs on tempering at 250°C, for steel ÉI643 at 400°C, and for steel D at 450–500°C.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 45–48, February, 1968.     

Die steels for high-speed automatic hot die forging machines

Conclusions Steel 3Kh3M3F produced by ESR has the best combination of strength, hardness, and toughness, and also resistance to crazing. The life of punches made of this steel was double that of standard steel 3Kh2V8F and considerably higher than that of steels with a higher carbon content (0.4–0.5%).The life of 3Kh3M3F punches (ESR) was three to four thousand bearing races higher than that of the same steel melted in an open furnace.These data lead us to recommend that punches for high-speed water-cooled presses be manufactured from steel 3Kh3M3F (ESR) with the following chemical composition: 0.26–0.34% C, 2.8–3.3% Cr, 2.5–2.9% Mo, 0.40–0.60% V (ChMTU-1-963-70).The following heat treatment is recommended: preliminary heating in an electric furnace at 500–510°, salt bath at 850–860°, and salt bath at 1040±10°. The parts should be quenched in oil with a temperature of 120–150°. The first tempering after quenching should be conducted in a salt bath at 600° for 2 h, with cooling in air. The second tempering should be conducted in a salt bath at 560° for 2 h, with cooling in air. The hardness of the parts after heat treatment is HRC 49–51.All-Union Scientific-Research Institute of the Bearing Industry. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 11, pp. 20–25, November, 1973.