Microstructure and wear properties of tungsten carbide reinforced steel matrix composites

摘要

WC (27 percent) reinforced steel matrix composites were produced by using an electroslag melting casting technique. The microstructure of the material was characterized using scanning electron microscopy(SEM) , optical microscopy and X-ray diffraction(XRD). Energy dispersive spectroscopy(EDS) and transmission electron microscopy were performed to investigate the interfacial composition between WC particle and steel matrix. The results reveal that the WC particles are partially melted into the steel substrate. At the same time, a reaction layer was detected along with the periphery of WC particle, which significantly enhances the bonding strength of the interface. A slipping wear (high stress abrasion) test was utilized to understand the wear behavior of this material. Abrasive experiment displays a better wear resistance than unreinforced steel matrix when coarse WC particles are dispersed into it. The coarse particles provide greater wear-resistance than the fine particles and operatively takes on the most applied loads. Additionally, the large particles have not been peeled during the wear process for a long time, which indicates the effect of interfacial reaction on wear behavior at the ambient temperature. A double carbide (Fe, W)_3C is detected in the interface zone between particles and matrices using transmission electron microscopy.