Technological conditions of diffusive boride coating formation on silicon carbide and molybdenum disilicide

Abstract

Summary. Basic directions of the diffusive boride coating formation on reaction-sintered silicon carbide and molybdenum disilicide are described. Technological conditions of non-metal ceramic materials boriding depending on the consideration of the amorphous boron concentration in the powder mixture are investigated and analyzed. It is determined that it is possible to speed up the rate of saturation process of the silicon carbide and molybdenum disilicide with boron by introducing sodium and aluminum fluorides as activating agents. Based on the carried out researches, optimal conditions for choosing the concentration of activating agents providing high saturation speed and improve operational parameters of the products are offered. It is also defined that to stimulate the process of boriding reaction-sintered ceramic materials, titanium hydride should be introduced into the saturated environment as the activating agent. Diffusion saturation of metals and alloys in hydrogen environment provides high saturation rate and good quality of the treated surface. The results of the carried out investigations prove that the saturation ability of the boride mixture increases significantly by introducing sodium fluoride and titanium hydride into it.