Performance characteristics of modified antifriction coatings based on the metal composition

Abstract

This paper proposes the technology for obtaining antifriction coatings by short-pulse laser treatment of powder compositions. (Research purpose) The research purpose is in synthesizing thin anti-friction coatings on the surface of steel substrates by short-pulse laser treatment of metal powder compositions and analyze their physical and mechanical properties. (Materials and methods) A solid-state pulsed laser generator was used to synthesize antifriction coatings. B83 babbit powder has been used as an additive material. The powder composition was additionally doped with PMS-1 copper and molybdenum disulfide in order to increase the friction properties and load-bearing capacity of the coatings. Laboratory samples were subjected to wear tests under boundary friction conditions using the SMT-2070 friction machine in comparison with standard surfaces of B83 babbite coating, steel surface, and Molykote d-321R clad surface. X-ray diffractometer DRON-6 was used for x-ray diffractometry. (Results and discussion) It was found that the porosity of the modified coating does not exceed 5 percent, and there are no traces of detachment and destruction in the experimental samples. It was found that the coefficient of friction of the analyzed coating under conditions of boundary friction was 0.12-0.13, which corresponds to the coefficient of friction of a standard babbit alloy. The modified coating have a more efficient workability and a stable coefficient of friction over a large range of loads. It was found that the wear intensity of the analyzed coating is significantly lower than one of the compared surfaces. The increase in friction characteristics is due to the features of the coating structure, which is characterized by a large number of solid intermetallic compounds Cu3Sn having a hexagonal structure, which determines the low friction coefficient. (Conclusions) The results shows the high practical potential of modified antifriction coatings that can be used in mechanical engineering and repair production in the design and restoration of bearing assemblies.