An Evaluation of crushing performance of a Boride layer formed on high strength wear resistant steel

Abstract

Boronizing treatment on the surface of wear-resistant steel can both improve the hardness and abrasion resistance of the surface layer and reduce the difference between the hardness of the boride layer and substrate, which can also greatly improve the crush performance and effeciently prevent the occurrence of brittle and fragile boronizing layer in the service process. In this paper, a boride layer without impurities was fabricated on the surface of high strength wear resistant steel (HSWRS) by solid powder boronizing treatment. The boriding behaviors of the HSWRS sample, including phase composition, microstructure, micro-hardness, wear resistance and crushing performance were investigated in comparison with those of 45 carbon steel borided at 1050 °C for 5 h. The results showed that the treated HSWRS was covered by a homogeneous boride layer. The boride layer was mainly composeded of Fe2B, V2B3, CrB2, MC, M2C. The highest micro-hardness value of the boride layer was about 1525 HV and the hardness took on gradient distribution from the surface to the center, and finally reduced to the hardness of the substrate. Compared to the borided 45 carbon steel, the boriding samples exhibit a similar surface toughness, but improved crushing performance.