Structure and Phase Composition of Boride Coatings on Sintered Powder Steels

Abstract

Results of metallographic and X-ray diffraction analyses of boride coatings produced by saturation of porous billets from iron–carbon powder alloys are provided. It is established that the structure and phase composition of boride coatings of iron–carbon powder alloys depend on the composition of borating mixtures: the amount of diffusion activator AlF₃ in the borating mixture essentially influences the structure, phase composition, and hardness of the coating and a higher amount of the activator intensifies the borating process leading to the formation of a very hard coating and borocarbides in the transition zone.