Tribological properties of Fe(Cr)-B alloys at high temperature

Abstract

This work is aimed to study the effect of boron on wear resistance of Fe-Cr-B alloys containing different boron contents (0 wt%, 5 wt%, 7 wt% and 9 wt%) from room temperature (RT) to 800 °C in order to explore their applications as high-temperature wear resistant mechanical parts. Additionally, the wear mechanism of alloys is evaluated. The tribological properties of alloys are systematically studied by using a ball-on-disc tribometer at 10 N and 0.20 m/s from RT to 800 °C sliding against Si3N4 ceramic ball. The boron element greatly improves the wear resistance of specimens as compared with that of unreinforced specimen. The friction coefficients of specimens decrease with increasing of testing temperature. The wear rates of Fe-Cr-B alloys decrease firstly and then raise with the increase of boron content. The specific wear rates of specimens with boron are 1/10 of the unreinforced specimen. Fe-21wt%Cr-7wt% B keeps the best tribological properties at high temperature.