Additive Manufacturing of Cemented Tungsten Carbide with a Cobalt-Free Alloy Binder by Selective Laser Melting for High-Hardness Applications

Abstract

Cemented tungsten carbide (WC) is commonly used for wear-resistant applications, such as cutting tools and abrasives due to its extremely high hardness. This hardness leads to post-process machining of WC to be time- and cost-intensive. This study examined the feasibility of additive manufacturing of cemented WC to near-net-shape in an effort to reduce post-process machining. The binder phase in the manufactured samples is an iron-based alloy, which has a lower melting temperature than cobalt, the conventional binder in cemented WC. In this proof-of-concept study, cuboid specimens of WC with a low content of the iron-based alloy binder were printed; the effect of different processing conditions on the resultant density and microstructure of the material were investigated. Theoretical densities as high as 95% were achieved using this method. Artifacts indicative of the manufacturing process are present in the samples, and the challenges in removing the processing history from the final microstructure are discussed.