Ultrafine grained WC-10FeCoCu cemented carbides doped with La2O3 prepared by spark plasma sintering

Abstract

La2O3/WC-10FeCoCu cemented carbides were fabricated using FeCoCu medium-entropy alloy (MEA) as a novel binder and La2O3 as a grain growth inhibitor via spark plasma sintering (SPS). Effects of sintering temperature and the amount of La2O3 on the microstructure and properties were investigated. WC-10FeCoCu with good mechanical properties was obtained. To further refine the grain size of WC, La2O3 was introduced as grain growth inhibitor. It was found that grain size of the WC-10FeCoCu samples added with 0.6 wt% of La2O3 is finer than 400 nm (388 nm). Its Vickers hardness and fracture toughness reach 1944.2 HV30 and 16.16 MPa∙mm1/2, respectively. The experimental findings highlight the successful preparation of La2O3/WC-10FeCoCu with ultrafine grains and favorable properties by using FeCoCu MEA as a binder and La2O3 as a grain growth inhibitor.