HIGH-STRENGTH MOLDING FORMED BY HIGH-DUCTILITY DIE-QUENCHING PROCESS AND METHOD FOR MANUFACTURING THE SAME

摘要

PPROBLEM TO BE SOLVED: To provide a high-strength molding having high ductility even though the molding is a member formed with a hot-pressing process, and to provide a method for manufacturing the same. PSOLUTION: The high-strength molding 1 is formed by heating a high-tensile-strength steel sheet to an austenite region, and press-molding and cooling the steel sheet in a die; and has a metallographic structure formed of a martensite structure in which carbides 2 are finely dispersed in the whole region including former-austenite grain boundaries. Furthermore, it is preferable to control grain sizes of the former-austenite in the structure of the high-tensile-strength steel sheet which is a base metal to 10 m or smaller. The high-strength molding has the martensite structure, and accordingly has high tensile strength and high ductility. PCOPYRIGHT: (C)2011,JPO&INPIT