Metal Science and Heat Treatment

Tarasovi, A.

doi: 10.1007/BF01154076pmid: N/A

The technical possibilities of vacuum elevator and bell furnaces commonly used for brazing and annealing precision parts in instrument-making and electronics can be widened. Small thin-blade tools of powder steels R6M5-P, 10R6M5-MP and “silver” steels R6M5, R6M5K5 with a minimum tolerance for sizing after hardening at a low cooling rate have high operational properties. The present paper is devoted to the process of heat treatment of special tools of the listed steels used to cut and shape ribbons, rods, and foils of alloys 36NKhTYu, 29NK, BrB2 in vacuum bcil furnaces under conditions of batch and small-batch production in electrical-engineering enterprises.

Gulyaev, A.

doi: 10.1007/BF01154077pmid: N/A

Safonov, A.; Aleksenko, S.

doi: 10.1007/BF01154078pmid: N/A

This paper is concerned with the reasons for the higher set of properties of steel 40Khl0S2M subjected to laser treatment with fusion compared to the properties after laser treatment without fusion. A comparative analysis of the properties of the steel after the two kinds of surface treatment is presented.

Astashkevich, B.; Zinov'ev, G.; Voronin, I.

doi: 10.1007/BF01154079pmid: N/A

The reliability of parts of the gas-distributing mechanism and drives of fuel pumps determines to a great degree the operating conditions of cylinder-piston parts and the economic characteristics of diesel engines. Intense wear of the camshaft pair disturbs the distribution phases and the lead angle of fuel supply to the diesel cylinders and increases the rigidity of the operation of the connecting rod-piston group. This causes incomplete combustion of fuel and fuming, a rise in the temperature of exhaust gases, sticking of the rings in the piston grooves and their premature failure, wear cracks, and chips and failure of the parts of the cylinder-piston unit, decreasing the efficiency of the diesel. Laser surface treatment is used to restore cams. It makes it possible to increase substantially the wear resistance of cams and restore their worn surfaces. This paper concerns the characteristics of the cams after such a treatment.

Poletika, I.; Borisov, M.

doi: 10.1007/BF01154080pmid: N/A

A high abrasion strength of facing layers is attained by introducing tungsten carbide into the facing metal. There is a tendency to replace the expensive tungsten carbide by less expensive facing materials that contain chromium as the main alloying element plus carbon and boron. The present work concerns the possibility of increasing the hardness and wear resistance of the surface layers of steel by using high-chromium mixtures instead of tungsten carbide in electron-beam facing.

Gulyaev, A.

doi: 10.1007/BF01154081pmid: N/A

This paper is devoted to the state of the problem of the deformation mechanism in metallic materials in stretching and presents some nonstantandard concepts developed by the author concerning the final stage of tensile plastic deformation before failure.

Antipov, A.; Moiseev, V.; Moder, N.

doi: 10.1007/BF01154082pmid: N/A

VT35 alloy belongs to β-titanium alloys that preserve the body-centered lattice of the β-phase in hardening from the β-region. In an equilibrium state this alloy has an α + β structure. After hardening, VT35 alloy has a high ductility and a low strength. The subsequent single- or double-stage aging in the biphase region promotes considerable strengthening of the alloy due to segregation of a second phase. VT35 titanium alloy is hardened to a “pure” β-phase by cooling from the single-phase region in water, in air, or with the furnace (at a rate of at least 3 -4 deg/min). This special feature of the alloy is caused by its chemical composition (Ti - 3% Al -15% V - 3% Cr - 3% Sn), which provides a high coefficient of β-stabilizationK β = 1.5. The present paper concerns the processes of age toughening of a hardened VT35 alloy and the kinetics of the structural transformations in such a treatment.

Sysoeva, N.; Polyakova, I.; Karpova, I.

doi: 10.1007/BF01154083pmid: N/A

The use of various methods of rapid hardening of melts opens wide possibilities for creating new titanium alloys strengthened by intermetallic compounds that possess elevated heat and creep resistances, strength, and other characteristics. The present paper concerns the regular features in the decomposition of alloy VT22 (in the form of granules) rapidly hardened from the liquid state and alloyed additionally with carbon and boron.

Kolachev, B.; Kondrashova, N.; Skol'tsov, V.; Drozdov, P.

doi: 10.1007/BF01154084pmid: N/A

Alloys of the VT6 type are used for parts operating in the temperature range from 450 -500°C to cryogenic temperatures. At room temperature and below, alloys of this type can develop hydrogen embrittlement. This paper is devoted to the effect of hydrogen on the mechanical properties of the alloy for temperatures ranging from room to that of liquid helium.