利用扫描电镜观察不同状态不同钢种白点断口的微观形貌, 描述了不同钢种预硬态、热轧态、退火态、调质态白点的微观形貌特点, 并分析了白点与夹杂物和偏析的关系。结果表明: 热轧态、退火态、预硬态钢种的白点形貌多呈碎条状、羽毛状准解理特征, 调质处理后钢中白点具有浮云状和蛀道花样形貌; 对白点敏感的钢种, 白点区不易发现夹杂物和碳化物的偏析, 但夹杂物或碳化物偏析的存在会增加钢产生白点的可能性。

The micromorphology of flake fracture of different steels at different status was observed by scanning electron microscope. The micromorphology characteristics of flakes in different steels at pre-hardening state, hot rolling state, annealing state, and quenching and tempering state were described. The relationship between inclusions, segregation and flakes was also analyzed. The results show that: the morphology of flakes in steels at hot rolling state, annealing state and pre-hardening state had quasi-cleavage characteristics like fragment stripes and feather; while the flakes in steels at quenching and tempering state had the morphology of floating cloud and wormholes; with regard to the steels which were sensitive to flakes, it was not easy to find inclusions and carbide segregation in the areas of flakes, while the existence of inclusions or carbide segregation would increase the probability of flake generation in the steels.