基于激光共聚焦显微镜模拟微合金钢连铸过程中第二相的析出行为

Precipitation behaviors of secondary phases in micro-alloy steels during continuous casting simulated by CLSM

通过高温激光共聚焦显微镜模拟了微合金钢在不同冷却工艺下的凝固过程,并原位观察该过程样品表面的变化,探讨样品表面变化与第二相析出的关联性.研究结果表明:随着微合金钢钢液的凝固冷却,样品表面会出现细小浮凸;该浮凸出现的温度及分布位置与第二相的析出理论计算及透射电镜表征结果一致;通过原位观察该浮凸的产生,可间接表征第二相的析出,有利于分析第二相对基体组织演变的影响.

Solidification of micro-alloyed steels under different cooling processes was simulated by confocal laser scanning micros-copy （ CLSM） , and the change of the sample surface was in-situ observed. The correlation between the change of the sample surface and the precipitation of secondary phases was discussed. It is found that some small reliefs appear on the sample surface during liquid steel solidification. The appearing temperature and the distribution of reliefs are consistent with the results of the theoretical calculation of secondary phase precipitation and the characterization of transmission electron microscopy （ TEM） . The precipitation of secondary phases can be indirectly characterized by in-situ observations of surface reliefs, which will be helpful to analyze the effect of secondary phases on the evolution of the matrix.