OBRABOTKAMETALLOV MATERIAL SCIENCE Том 23 № 3 2021 EQUIPMEN . INSTRUM TS Vol. 6 No. 2 2024 Conclusion 1. It is experimentally proved that the strain resistance and strain energy, as well as the density of the spherical sliding bearing ring made of corrosion-resistant steel powders, obtained by cold forming of sintered blanks, are influenced by the configuration of the end surface of punches. The top and bottom edges are most intensively compacted when the punch faces are made with a chamfer angle of 30–40 deg. 2. It is established that in the production of one-piece spherical sliding bearings it is advisable to use sintered cylindrical blanks coated with lubricants containing solid particles of molybdenum disulfide and polytetrafluoroethylene, which makes it possible to reduce the strain resistance during cold forming of the outer ring by 20–30 %, and the sliding friction coefficient during operation is within 0.05–0.06. 3. It is revealed that mechanical and technological properties of sintered blanks from chromium-nickel stainless steels are influenced not only by the chemical composition of powders, but also by the mode and conditions of press sintering. The ultimate strength of specimens sintered in vacuum is 230–240 MPa, and in dissociated ammonia the ultimate strength is 40–45 MPa due to intensive oxidation of chromium on the boundaries of powder particles not only by oxygen contained in the protective environment, but also with oxygen slammed in the pores of the blank. 4. A simpler method of calculated and experimental determination of the contact friction coefficient is developed, which makes it possible to evaluate the influence of the degree and work of deformation, composition of lubricants containing solid particles of molybdenum disulfide and PTFE on the kinetics of forming at obtaining parts of various configurations by cold die forging of porous blanks. References 1. Dorofeev Yu.G., Gasanov B.G., Dorofeev V.Yu., Mishchenko V.N., Miroshnikov V.I. Promyshlennaya tekhnologiya goryachego pressovaniya poroshkovykh izdelii [Industrial technology of hot pressing of powder products]. Moscow, Metallurgiya Publ., 1990. 206 p. EDN: OFSEDO. Fig. 13. Dependence of the coefficient of contact friction during radial deformation of an annular specimen on the degree of transverse strain (εr = 0.05 (a); εr = 0.24 (b), εr = 0.42 (c)) and lubricant composition: 1 – pencil graphite; 2 – PTFE; 3 – MoS2 a b b d
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