METHOD FOR MANUFACTURING TWINNING-INDUCED PLASTICITY STEEL SHEET BY UTILIZING DYNAMIC RECRYSTALLIZATION AND TWINNING-INDUCED PLASTICITY STEEL MANUFACTURED BY THE SAME

摘要

The present invention relates to a method for manufacturing a twinning induced plasticity (TWIP) steel sheet having improved strain rate and yield strength and a TWIP steel sheet manufactured by the method. Disclosed is the method for manufacturing a TWIP steel sheet and the TWIP steel sheet manufactured by the method comprises the following steps of: heating TWIP steel composed of 15-20 wt% of Mn, 0.5-1.0 wt% of C, 0.5-2.0 wt% of Al, and the remainder Fe and other inevitable impurities; hot-rolling the heated TWIP steel; cooling the hot-rolled TWIP steel; warm-rolling the cooled TWIP steel; and winding the warm-rolled TWIP steel. [Reference numerals] (S110) Heat a TWIP steel sheet at 1100-1200C; (S120) Hot-roll the heated TWIP steel sheet; (S125) Reheat the hot-rolled TWIP steel sheet up to 500-700C after cooling the TWIP steel sheet down to room temperature; (S130) Cool the TWIP steel sheet down to 500-700C; (S140) Warm-roll the TWIP steel sheet up to 500-700C; (S150) Wind the TWIP steel sheet at 500C or below