The Effect of Graphite Content on the Wear Behavior of Ni/WC/G Composite Coating

Abstract

The Ni/WC/G composite coating was fabricated through vacuum cladding. The effect of graphite content on the wear behavior was investigated, and the worn surface was observed through scanning electron microscopy (SEM). The friction coefficient decreased with the increasing graphite content until the graphite content was 6%, and then increased when the graphite content was 8%. The wear rate decreased with the increasing graphite content for all graphite content. The wear loss of GCr15plate decreased with the increasing graphite content until the graphite content was 6%, and the wear loss of plate was rising when graphite was 8%. There was a layer composed of wear debris that containing oxides and graphite. The covering area increased with the increasing graphite content, which agreed with the changing trend of friction coefficient and wear rate. The net texture-like structure was formed among the composite coating, which could be the main support for load during wear process. There was little single WC particle protruding for support the wear load. Therefore, the Ni-based substrate was not easily to be worn.