BLAST MACHINING METHOD AND BLAST MACHINING DEVICE

摘要

Provided is a blast machining method or the like having high machining accuracy. The disclosed blast machining method is for forming a recess (9) in the surface of an object being machined (8) so as to conform with a target recess of a predetermined shape by blasting a blast material (21) onto the surface of the object, the method involving: a step of denting the surface of the object by blasting the blast material (21) onto the same in order to form a provisional recess (91) smaller and shallower than the target recess; a step of removing foreign substances in the provisional recess (91) by blowing a gas toward the provisional recess; a step of measuring the depth of the provisional recess (91) in a manner so as to trace the inner-surface shape of the provisional recess (91); a step of determining the target distance by which the provisional recess (91) is to be further dented, the determination being made based on the depth of the predetermined target recess and the result of measuring the depth of the provisional recess (91); and a step of further denting the provisional recess (91) by blasting the blast material (21) in accordance with the target distance.