Growth kinetics and abrasive wear resistance of boride layers on Fe–15Cr alloy

Abstract

Two boride layers based on the FeB and Fe₂B compounds are formed at the interface between an Fe–15Cr alloy and boron at 850–950°C and reaction times up to 12 h, with the average chromium content being around 8 at-% in the former and 12 at-% in the latter. Both boride layers reveal a pronounced texture. Diffusional growth kinetics of the layers are close to parabolic and can alternatively be described by a system of two non-linear differential equations. Microhardness values are 17·4 GPa for the FeB layer, 14·4 GPa for the Fe₂B layer and 0·95 GPa for the Fe–15Cr alloy base. The dry abrasive wear resistance of borided alloy samples is around 45 times greater than that of non-borided ones.