Abstract: Recently, hard-brittle optical crystal material is applied widely in the aviation and spaceflight, optics, optoelectronic industries. The technology of ultra-precision cutting of hard-brittle optical crystal material have received an much attention. A brief introduction covering the evolution process and the recent studies of cutting model, brittle-ductile transition mechanism and research ways and means of this technology is presented.

Key words: Brittle-ductile transition, Cutting model, Hard-brittle material, Mechanism