1000 MPa级连续退火双相钢的组织与性能研究
Study on Microstructure and Properties of Continuous Annealing DP1000 Dual-phase Steel
乔建军1, 牛 枫2
作者单位：(1. 北京首钢冷轧薄板有限公司, 北京 101300; 2. 北京科技大学 冶金工程研究院, 北京 100083)
中文关键字：连续退火； 双相钢； 过时效； 组织
英文关键字：continuous annealing; dual-phase steel; over-ageing; microstructure
中文摘要：在实验室试制了1000 MPa级连续退火双相钢，利用光学显微镜、 SEM、 TEM以及拉伸试验对双相钢的微观组织和力学性能进行检测。 结果表明， 保温温度830 ℃， 保温时间60 s，快冷至过时效温度240 ℃， 过时效时间240 s，可以得到屈服强度535 MPa、抗拉强度1145 MPa、屈强比0.47、 伸长率13%，具有较好综合性能的高强双相钢；抗拉强度随过时效温度的升高呈下降趋势， 屈服强度、 伸长率和屈强比呈上升趋势，在过时效温度为360 ℃时，出现屈服平台。
英文摘要：1000 MPa grade dual-phase steel was piloted in laboratory. Optical microscopy, scanning electron microscopy, transmission electron microscope and tensile tests were used to characterize the microstructure and mechanical properties. The results indicate that soaked at 830 ℃for 60 s, then rapidly cooled to 240 ℃, the dual phase steel can get excellent mechanical properties. The yield strength is 535 MPa, the tensile strength is 1145 MPa, the yield ratio is 0.47 and the elongation percentage is 13%; the tensile strength reduces with over-ageing temperature increasing. The yield strength, yield ratio and elongation percentage increase with over-ageing temperature increasing. The yield point appears at 360 ℃.