Study of the three-body impact abrasive wear behaviour of a low alloy steel reinforced with niobium

In order to improve the wear resistance of steel, a new Nb-added reinforced low-alloy wear-resistant steel was developed, and the wear behavior of the three-body impact abrasive was systematically studied under the impact energy of 0.5J, 2.5J, 4J, 5J. Tensile testing, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nanoindentation were used to characterize the mechanical properties, microstructure evolution and wear mechanism of steel. The experimental results show that NB05 (0.05 wt%-Nb) steel with smaller size lath martensite has higher strength performance and better impact wear resistance than NBO (0 wt %-Nb) steel. During three-body impact abrasive wear tests, the corrected wear rate was less under higher impact energy for both steels, and the NB05 steel owned less wear rate than NBO. The main strengthening mechanisms of the wear layer were newly formed martensite twins, niobium precipitates, high density dislocations and the formation of nanoscale grains for the NB05 steel. The wear mechanism of the wear layer is mainly reflected in buffering, lubrication and protection of debris.