600MPa级热镀锌双相钢再结晶和相变规律研究

Study on Regularities of Recrystallization and Phase Transformation in Hot Dip Galvanized Dual Phase Steel with 600 MPa

在Gleeble-3800热模拟机上对600MPa级热镀锌双相钢进行了连续退火工艺模拟实验，利用光学显微镜与扫描电镜观察分析了600MPa级热镀锌双相钢在连续退火过程中的再结晶和相变规律。结果表明，600MPa级热镀锌双相钢在连续退火初期。650～700℃加热范围内再结晶剧烈进行。加热速度提高，冷变形组织的再结晶开始与结束温度也相应升高。两相区保温后快速冷却得到不同体积分数的铁素体和马氏体组织，随两相区保温温度升高，马氏体特征更加明显。

The simulated test of the continuous annealing technology is made by the Gleeble - 3800 thermal simulator for the hot dip galvanized dual phase steel with 600 MPa. The regularities of recrystallization and phase transformation in the hot dip galvanized dual steel with 600 MPa during the continuous annealing are analyzed by the optical microscope and scanning electron microscopy. The results show that the recrystallization in the heating range from 650 to 700℃ is occurring strong- ly for the hot dip galvanized dual steel with 600 MPa at the preliminary stage of the continuous an- nealing. The temperatures both at the beginning and at the end of the recrystallization of the cold de- formation microstructures increase with the increasing of the heating speed. The ferrite and martens- ite mierostructures with different volume fractions are formed after soaking and subsequently rapid cooling the two - phase region. The martenite characteristic appears much more obviously as the soa- king temperature in the two- phase region is increasing.