Abstract: A method for surface treatment of a workpiece made from a hard-brittle material comprises first blasting employing abrasive grains of higher hardness than a hardness of a base material of the workpiece for forming a three dimensional recess-protrusion profile having protrusions and recesses formed between the protrusions on a surface of the workpiece; and second blasting employing an elastic abrasive having a structure in which abrasive grains carried in and/or on an elastic body made from material with low rebound elasticity for polishing the surface of the workpiece formed with the recess-protrusion profile so as to achieve an arithmetic average roughness Ra of not greater than 1.6 ?m on the surface of the protrusions and the recesses on the workpiece while maintaining the recess-protrusion profile formed by the first blasting.

Abstract: A method for surface treatment of a workpiece made from a hard-brittle material comprises first blasting employing abrasive grains of higher hardness than a hardness of a base material of the workpiece for forming a three dimensional recess-protrusion profile having protrusions and recesses formed between the protrusions on a surface of the workpiece; and second blasting employing an elastic abrasive having a structure in which abrasive grains carried in and/or on an elastic body made from material with low rebound elasticity for polishing the surface of the workpiece formed with the recess-protrusion profile so as to achieve an arithmetic average roughness Ra of not greater than 1.6 ?m on the surface of the protrusions and the recesses on the workpiece while maintaining the recess-protrusion profile formed by the first blasting.