Microstructure and tribological behavior of in situ ZrB2/A356 composites prepared under magnetic field

Abstract

A356-3 wt% ZrB2 composite was prepared by in-situ magnetochemical reaction at x Hz(x = 0, 5, 10, 15) magnetic field frequency, and its dry sliding friction and wear properties were studied. XRD results show that the composite is composed of ZrB2 and aluminum phase. SEM analysis showed that the size and distribution of ZrB2 particles improved with the increase of frequency. The size of ZrB2 particles in the cluster is about 20–100 nm. The hardness test results showed that with the increase of frequency, the hardness of the composite increased to 235.72 Hv. The friction and wear test results show that the friction coefficient and wear rate of the composite material under 10 N load are lower than that under 5 N load, and the lowest values are 0.28112 and 0.50875, respectively. With the increase of frequency, the wear mechanism changes from adhesive wear to abrasive wear. The effect of magnetic field on in-situ reaction is discussed.