자동차용강의 고속변형거동에 대한 예비변형과 소부경화의 영향

The high speed deformation behavior of TRIP steels and HSLA steels has been investigated at strain rates ranging from 10^(-2) to 10³/sec. The effects of metallurgical factors such as prestrain (2%) and bake hardening condition (170℃, 20 min) on tensile properties at various strain rates are being evaluated. Ultimate tensile strength (UTS), total elongation, strain rate sensitivity, and absorbed energy are reported. In general, UTS increases with increasing strain rate, that is, it shows positive strain rate sensitivity. And strain rate sensitivity increases sharply over 100/sec. Strength increases with increasing the amount of prestrain. The bake hardening treatment slightly influences UTS values. The absorbed energy decreases with increasing prestrain but it is not affected by bake hardening treatment. Received February 14, 2005)