Damage Resistance of Corundum Treated with Abrasive and Contact-Free Processing

The planishing of the surface of solids is aimed to minimize its roughness, downgrade a content of larger cracks in the modified layer, and, in general, reduce a thickness of the latter one. However, the abrasive processing induces residual stresses in the surface layer. The stresses relax through the motion of dislocations but in superhard materials like corundum or silicon dioxide, is extremely limited. In the present work, the role of the modified surface layer in corundum was studied within the context of the method and regime choice which affect the surface processing the mechanical characteristics of corundum. An efficiency of the abrasive treatment was assessed by comparison with the properties of surfaces processed with the ion polishing, sheared surface, and natural face of crystal from the viewpoint of reaching the high mechanical damage resistance of the surface.