EDM machinability and dry sliding friction of WC-Co cemented carbides

A number of WC-Co cemented carbides with 6–12 wt. % Co were machined and surface finished by grinding or Electrical Discharge Machining (EDM). EDM was executed in deionised water through several consecutive gradually finer steps. Correlations between Material Removal Rate (MRR), surface finish and EDM parameters were derived. The quality and integrity of surface finishes were analysed by Scanning Electron Microscopy (SEM). Dry reciprocating sliding experiments on EDM’ed and ground samples against WC-Co pins using a Plint TE77 tribometer revealed a considerable impact of the EDM process as well as distinctive EDM finishing steps on the friction coefficient. [Received 4 September 2008; Revised 5 January 2009; Accepted 3 April 2009]