Effect of heat and thermomechanical treatments on the structure and physical and mechanical properties of the N30K10T3 invar

Invar alloy N30K10T3, whose austenite is metastable with respect to the martensitic γ → α transformation that occurs upon cooling below the martensitic point (M _s = ?80°C), has been studied. The following six ways of the alloy strengthening have been tested: (1) aging (a) in a temperature range of ΔT _a = 20–700°C; (2) liquid-nitrogen cooling (lnc) of the material preliminarily hardened by aging under the aforementioned conditions (route 1) (a + lnc); (3) preliminary phase-transformation-induced hardening (ph) (γ → α → γ_ph) and aging in the temperature range of ΔT _a (ph + a); (4) liquid-nitrogen cooling of the material preliminary hardened via route 3 (ph + a + lnc); (5) preliminary cold deformation (to 30%) at room temperature and aging in a temperature range of ΔT _a (cd + a); and (6) liquid-nitrogen cooling of the material preliminary hardened via route 5 (cd + a + lnc). The six ways of hardening were found to affect the hardness, electrical conductivity, magnetic permeability, and temperature dependence of the thermal expansion coefficient.     

Effect of severe plastic deformation on the properties of the Fe-36% Ni invar alloy

Temperature dependences of the magnetization and thermal expansion coefficient of the Fe-36% Ni invar alloy in different structural states obtained upon plastic deformation by torsion under a quasihydrostatic pressure followed by annealing at different temperatures are studied. A decrease in the thermal expansion coefficient of the invar in a temperature range of 20–100°C and the formation of ordered precipitates (with a superstructure) were found to result from severe plastic deformation.     

Effect of cold deformation on the properties and structure of corrosion-resistant alloy KhN30MDB

The effect of the degree of cold deformation on the structure and mechanical and corrosive properties of the corrosion-resistant alloy KhN30MDB have been studied in detail. Deformation regimes that provide for a high level of strength properties and satisfactory plasticity, combined with high corrosion resistance, including general and pitting corrosion and sulfide corrosion cracking in hydrogen sulfide, have been determined. Original Russian Text ? T.V. Svistunova, 2008, published in Korroziya: Materialy, Zashchita, 2007, No. 11, pp. 1–6.     

Effect of plastic deformation on the mechanical properties and structure of alloy Mg-3.6% Sm

Alloys based on magnesium which exhibit low density and specific strength are used as light structural materials. Alloying of magnesium alloys with REM promotes an increase in their strength properties both at room and elevated temperatures. The possibility is studied of an additional increase in strength properties on alloying magnesium with samarium as a result of plastic deformation.A. A. Baikov Institute of Metallurgy, Moscow. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 1, pp. 24–26, January, 1994.     

Effect of low-rate isothermal plastic deformation on the structure and properties of ZhS6KP nickel alloy

ZhS6KP alloy is used in commercial production of blades of aircraft engines pressed in Widin presses. Standard heat treatment that consists in air hardening from 1220°C (4 h) and aging at 950°C for 2 h with cooling in air does not always provide an optimum combination of long-term strength and fatigue resistance for the alloy at 900°C. In this connection, the possibility of improving the fatigue resistance and the long-term strength while preserving the high level of short-term mechanical properties by conducting low-rate plastic deformation before the heat treatment is considered.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 31 – 33, July, 1996.     

Effect of preliminary cold plastic deformation on the properties of maraging steels

Conclusion Cold plastic deformation (rolling and forging) increases the strength of quenched maraging steels with no substantial reduction of the ductility. The effect of strain hardening is more evident after subsequent aging, the preliminary cold deformation leading to acceleration of aging processes, which is due to earlier formation of intermetallic phases.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 9, pp. 15–18, September, 1975.     

Effect of various kinds of severe plastic deformation on the structure and electromechanical properties of precipitation-strengthened CuCrZr alloy

The effect of various kinds of severe plastic deformation (equal-channel angular pressing and quasi-hydrostatic extrusion at 77 and 300 K) on the structural formation of precipitation-strengthened CuCrZr alloy has been studied. A combination of experimental methods has been used. Sputtering by deuterium ions was used as the tool for the layer-by-layer study of the alloy structure. The difference between the sputtering yields of the matrix (copper) and precipitates (Cr and Zr) allowed us to visualize the alloy structure to a total depth of 0.5?1 μm. The effect of severe plastic deformation on the precipitate distribution is considered. It has been shown that the main peculiarity of the microstructure is related to the high density of precipitates enriched in chromium, which completely determine the surface roughness. Their distribution is not related to the grain size. The combination of equal-channel angular pressing and quasi-hydrostatic extrusion was shown to lead to the increase in the microhardness of the CuCrZr alloy to 2300 MPa in the case of low-temperature quasi-hydrostatic extrusion (at 77 K) and to the retained high conductivity. It has been proved that the high anisotropy of precipitate shape, microhardness, and sputtering yield of the CuCrZr alloy is determined by equal-channel angular pressing.     

Effect of plastic deformation on the structure and properties of laminated composite materials

Experience with the development and application of plasma cutting of metals using reversed polarity current and mixed gas supply is described. The high efficiency of plasma cutting with reversed polarity in both the manual and automatic cutting modes in the plant conditions is stressed. It is noted that the number of activations of the constricted arc can be greater than 1000 without failure of the electrode.     

固溶-时效热处理对易切削变形Zn-10Al-1.0Cu-xBi-ySn合金组织与性能的影响

采用力学性能测试、扫描电镜、透射电镜和能谱分析技术、切削性能测试研究固溶-时效热处理工艺对自行研制的易切削变形Zn-10Al-1.0Cu-xBi-ySn合金挤压态组织与性能的影响。结果表明:为获得较佳的综合性能,该合金较佳的热处理工艺为(350℃,30 min水冷)+(100℃,12 h空冷);经过合理的热处理后,合金中的α+η胞状和粒状组织增多,层片状组织减少,合金塑性提高;热处理后该合金的抗拉强度达到327.05 MPa,伸长率为20.5%。