HIGH-STRENGTH STEEL SHEET AND THE METHOD FOR PRODUCTION THEREFOR

摘要

A high-strength steel sheet comprises, by weight, not less than 0.25% and not more than 0.5% of C, not less than 4% and not more than 14% of Mn, not less than 6.5% and not more than 9.5% of Cr, and not less than 0.3% and not more than 3% of Si. The high-strength steel sheet satisfies the following formulas 1 and 2 and mainly consists of austenite, and the high-strength steel sheet has yield strength of not less than 1000 MPa and total elongation of not less than 20%. 12≰2.0Si+5.5Al+Cr+1.5Mo≰25  (1) 13≰30C+0.5Mn+0.3Cu+Ni+25N≰17  (2) (Each element symbol in the above formulas indicates the content (weight %) of the element)