Wear Resistance of Laser Treated Partially Stabilized Zirconia

The laser beam treatment of magnesia partially stabilized zirconia (Mg-PSZ) sample surfaces has shown a considerable improvement in their wear resistance and surface hardness. The laser beam treated surfaces exhibited higher wear resistance than either ground untreated or ground and laser treated ceramic surfaces. There are optimum combination of the laser treatment process parameters (laser power and exposure characteristics) that resulted in the minimum wear rate or the maximum surface hardness. There was no correlation found between the wear rate and the surface hardness. There were two wear mechanisms operational, namely, surface fracture and surface polishing. The treatment of the ceramic surfaces reduced the fracture component of the wear rate. The laser treatment effect on the polishing process was not detected. The increase in the wear resistance and the surface hardness of the laser beam treated surfaces were due to the thermally induced phase transformations resulted in the formation of the compressive stress field on the surface and altering the surface structure.