CUTTER

摘要

A cutting instrument (1) has a cutting blade portion (13) formed with a skin (7) made of an electrode material or a reaction product of the electrode material, the electrode material having been molten by pulse discharges induced between the cutting blade portion (13) and an electrode in a machining liquid or gas, having as the electrode one of a mold molded from powder of a kind or powder of a mixture of kinds out of a metal or metals, a metal compound or metal compounds, and a ceramic or ceramics, and a heat-treated mold being the mold as heat-treated.