High-pressure infiltration fabrication of WC-based self-lubricating ceramics with synergistic enhancement of mechanical and lubrication properties

The mechanical performance defects of self-lubricating ceramics bottleneck restricting their development and application. Such a defect is attributed to the lubricant's hindering effect on the substrate's bonding during the sintering process. Here, we report a high-pressure infiltration scheme and present a two-step approach for preparing WC-based self-lubricating ceramics with excellent mechanical and lubrication properties. We have demonstrated that the process breaks through the limitations between mechanical and lubrication properties to improve the wear resistance of the ceramics significantly. The effects of residual stresses due to lubricating phases and the complex three-dimensional pore structure within the ceramics deserve extensive discussion. A multiple lubrication mechanism involving multiple particles is proposed based on frictional wear analysis. This straightforward strategy opens a gate to developing the next generation of self-lubricating ceramic materials.