Al对冷轧双相钢高温热塑性的影响

Effect of Aluminum Amount on the Hot Ductility of the Dual Phase Steel

采用Gleeble2000高温力学性能模拟试验机对不同铝含量双相钢高温热塑性进行了对比研究。结果表明,Al的加入使得双相钢的高温低塑性区向高温区域偏移,温度区间由低铝时的710～920℃升高到高铝时的800～1020℃;为了避免铸坯表面产生裂纹,高铝双相钢矫直段温度应控制在1050～1150℃范围内,冷却水应采用弱冷水制度,并合理控制钢中的N、S及O的含量。同时发现,试验钢高温热塑性随着应变速率的增大而提高。

The hot ductility of two kinds cold-rolled dual-phase steel with the different aluminum amounts has been investigated. The results indicate that the high aluminum amount led the hot brittleness zone shift to the higher temperature zone, and the temperature zone shifted from 710-920 ℃ of the low-aluminum steel to 800- 1020℃ of the high-aluminum steel. In order to avoid the occurrence of the surface cracking during continuous casting, the temperature of the high-aluminum slab at the straightening stage should be maintained between 1050-1150 ℃, the secondary cooling water should be soft and the amount of N, S, O in the steel should be properly controlled. It is also indicated that the hot ductility of the steel is improved with the increase of the strain rate.