ФОРМУВАННЯ ЗНОСОСТІЙКИХ ГАЗОТЕРМІЧНИХ ПОКРИТТІВ НА ТИТАНОВИХ СПЛАВАХ

Abstract

Досліджено закономірності формування детонаційних плазмових покриттів. Виконано хімічний і фазовий рентгено-структурний аналіз порошку та покриттів після напилювання. Представлені результати дослідження зносостійкості отриманих покриттів.

The patterns of formation of detonating plasma coatings are investigated. Chemical and phase X-ray-structural analysis of powder and coatings after spraying are performed. The study results of the obtained coatings wear resistance are presented. It is established that the coating structure after spraying consists of carbides particles distributed in the metal matrix, as well as oxide of the weeping elements. The microstructure is heterogeneous in terms of the components structure, their microhardness and distribution. The microhardness of the particles varies depending on the type of the curing metal and the size of the carbides. If the output particles are 80-100 μm, the carbide impregnation has a microhardness of 14-29 GPa. With a decrease in the magnitude of the source particles there is a more complete interaction with the material in the process of spraying. Microhardness of carbides at the same time decreases. The sizes of carbide particles in the plasma coating of titanium carbide, covered with nickel and copper, are 20-60 μm. In the structure there are separate conglomerates of particles that are formed obviously at the stage of the powder coating. The structure of detonation coatings is characterized by a more even distribution of particles in the matrix, their microhardness does not exceed 12 GPa, the size - no more than 10 - 15 microns. According to the abovementioned studies, it has been established that titanium alloys have low antifriction properties: high and unstable friction coefficient and are disposed to solidification. The main way of increasing the efficiency of titanium alloys in the nodes of friction - the application of coatings on parts of these alloys. The most promising coatings that are applied by various spraying methods, due to technological capabilities, technical and economic indicators, that have significant advantages over traditional coating methods.