Effect of (Ti,W)C/TaC addition on the early oxidation behavior of surface layer of WC-Co cemented carbides

Abstract WC-Co-based cemented carbides with cubic carbides (Ti,W)C/TaC were prepared and the early oxidation behavior of their surface layers was investigated. Different carbides exhibit independent oxidation processes and selective oxidation behavior. The solid solution containing Ti slows the oxidation process due to its high stability. In addition, an oxidation stage model was established to describe the formation of surface oxide scale of cemented carbides. The increasing (Ti,W)C/TaC content is beneficial to hinder the oxygen diffusion at 500-700 °C during the early oxidation. Selective oxidation of carbides is the main reason to change the oxidation resistance of surface layer.