| 摘要 |
PROBLEM TO BE SOLVED: To provide a high carbon steel sheet for precision blanking which has excellent precision blanking properties and can be subjected to induction hardening. SOLUTION: The structure of a medium carbon or high carbon steel sheet comprising 0.15 to 0.90 wt.% C is regulated to the one where carbides with a spheroidizing ratio of≥80% and a mean grain size of 0.4 to 1.0μm are dispersed into a ferrite matrix, and its notched tensile elongation El<SB>V</SB>is controlled to≥20%. Further, when its D value [=(3×El<SB>V</SB><SP>2</SP>+18×El<SB>V</SB>)/TS] (wherein TS is a tensile strength) is controlled to≥3, the service life of a die is improved as well. COPYRIGHT: (C)2010,JPO&INPIT |
