Influence of electrical discharge machining on the reciprocating sliding wear response of WC-Co cemented carbides

A number of commercially available WC-Co-based cemented carbides with 6 up to 12 wt.% Co were machined and surface finished by grinding as well as by wire electrical discharge machining (EDM) in demineralised water through a number of consecutive gradually finer EDM regimes. Comparative dry reciprocating sliding wear experiments on both wire-EDM and ground samples against WC-Co pins were conducted, using a pin-on-plate test rig, in order to investigate the influence of the EDM process on the tribological behavior. The worn surfaces of the investigated cemented carbides were scanned topographically and characterised by scanning electron microscopy (SEM). The post-mortem obtained wear volumes were compared to the online measured wear in order to determine correlations between wear volume and wear rate on the one hand and sliding distance on the other hand. The experimental results revealed a profound influence of surface finish conditions and distinctive EDM regimes on the wear behavior of WC-Co cemented carbides.