Ultra-low wear of WC/bronze composite prepared by binder jet printing and infiltration via amorphous-crystalline nanocomposite tribofilm

Anti-wear performance is vital for the lifespan of moving component. Herein, ultra-low wear, even negative wear was obtained for the tungsten carbide/bronze composites prepared by additive manufactured binder jet printing (BJPWC), especially when sliding contact with silicon carbide (SiC) ceramic. Sliding interface observation reveals that the promising tribological performance of SiC/BJPWC is ascribed to the in-situ formed stable tribofilm which can deliver beneficial friction reduction and anti-wear effects. The friction process between SiC balls and WC/bronze composite under varying loads induces the diffusion of Si atoms toward the sliding interface, where they form negative mixing enthalpy and network chemical bonds with other metals, promoting the amorphization of the tribo-layer. An in-situ formed unique nanocomposite protective layer is generated, in which Cu/WC nanocrystals are uniformly dispersed within a silicate amorphous matrix. This unique structure effectively accommodates friction-induced plastic deformation and resist damage. This work can provide some basic understandings for the ultra-low wear materials, and guides the selection of sliding counterparts for future application of additive manufactured component.