A facile route to prepare ODS WC Co cemented carbides

Abstract Oxide dispersion strengthened (ODS) WC Co cemented carbides with excellent mechanical properties were prepared by a facile three-step method. First, the mixture of ammonium paratungstate, cobalt oxalate and aluminum nitrate nonahydrate were roasted to generate precursor powder. Then, the precursor powder was reacted with insufficient carbon black to remove oxygen to aid precise carbon addition in the next step. Finally, depending on the carbon content difference between carbothermic reduction products and target product, the sample was mixed with the required carbon black to prepare WC Co Al2O3 cemented carbides directly by the method of powder sintering. Experiments showed that after the addition of uniformly distributed nano-sized Al2O3 particles, the mechanical properties included hardness and toughness of ODS cemented carbides improved. When the content of Al2O3 was 0.5%, the densification of finally prepared WC-5.5wt%Co-0.5wt%Al2O3 alloy could reach to 99.08%, and the values of fracture toughness and Vickers hardness were 11.35 ± 0.60 MPa·m1/2 and 1756 ± 20.92 HV, respectively, thus giving excellent results.