DIE MANUFACTURING METHOD AND DIE

摘要

[Problem] To provide a die, which is molded by wire electric discharge machining and for which dimensional changes that occur with time can be limited, and a die manufacturing method. [Solution] The manufacturing method is provided with a forming process (S1) of forming the die and a dimensional change-limiting process (S2) of performing heat-treatment after the forming process (S1) to limit dimensional changes that occur with time. The forming process (S1) is provided with a hardening process (S11) of hardening the die material that has been rough-processed, a tempering process (S13) of tempering the die material after the hardening process (S11), and a machining process (S15) of shaping the die by wire electric discharge machining of the die material after the tempering process (S13). In order to improve the state of the heat-affected zone formed from the machining surface towards the interior by the wire electric discharge machining, a medium temperature tempering process in which the tempering temperature is 350-400°C is performed in the dimensional change-limiting process (S2) as the heat-treatment for limiting dimensional changes that occur over time.