27SiMn钢连铸圆坯中心星形裂纹分析

Center Crack Reason Analysis of 27SiMn Continuons Casting Billet

对27SiMn钢连铸圆坯中心星形裂纹产生原因进行了研究。采用金相显微镜、扫描电子显微镜及X射线能谱仪对中心星形裂纹的宏观和微观特征、化学成分、显微组织进行分析,结果表明:中心星形裂纹是连铸坯最后凝固钢液形成的卵形树枝晶在张应力作用下形成的空隙。

Star central crack causes of 27SiMn continuous casting round billet were analyzed by means of chemical composition analysis,macroexamination,microstructure examination and scanning electron microscopy and X-ray spectrometer.The result shows that the star central crack is the gap formed by oval dendrite under tensile stress in the central of continuous casting billet.These features indicate that insufficient replenishment of liquid metal in the last solidification place causes the cracks in the center.