电镜分析在解决铸件夹渣缺陷上的有效应用

Application of SEM Analysis to Effectively Solve Slag Inclusion Defect of Castings

介绍了马达壳体铸件的生产工艺及铸件加工后存在的夹渣缺陷,借助扫描电镜分析缺陷的组织成分及此类组织成分的来源,分析认为,该缺陷是由使用的FeSi孕育剂未熔化所致。最终有针对性地确定了解决方案:将孕育方式由随流孕育改成出炉孕育,孕育剂粒度由0.6~0.8 mm改为1~3 mm,加入量由0.4%调整为0.3%,浇注温度由1350~1370℃提高至1360~1380℃。生产结果显示:经过小批量试验及批量生产验证,马达壳体铸件的成品率由85%提升到98%以上,夹渣类缺陷得到了有效控制。

An introduction was given to the production process of motor housing casting and slag inclusion defect found after casting being machined.By using SEM the constituents of defect and their resource were analyzed.It was considered by analysis that the slag inclusion defect was caused due to the FeSi used as inoculant was not melted.The solution scheme was finally determined:the inoculation process was changed from stream inoculation to tapping inoculation,the grain size of inoculant changed from 0.6~0.8 mm to 1~3 mm,adding amount changed from 0.4%to 0.3%,pouring temperature changed from 1350~1370℃to 1360~1380℃.Production result showed:according small batch trial and batch production validation,the qualified rate of motor housing casting was elevated from 85%to higher than 98%,the slag inclusion defect had been effectively controlled.