上盖铸铁件皮下气孔成因分析与防止措施  

Cause Analysis and Prevention Measures of Pinhole on Cast Iron Cover

作　　者：程俊伟[1] 黄胜操[1] 杨永生[1] 吕乐华[1] 常征[1] 

机构地区：[1]中国一拖集团有限公司,河南洛阳471004

出　　处：《现代铸铁》2016年第3期70-72,76,共4页Modern Cast Iron

摘　　要：介绍了铸件的结构及生产情况,利用扫描电镜和能谱分析仪分析了湿型粘土砂铸铁件皮下气孔缺陷的形成原因,采取了以下改进措施：（1）过滤细碎孕育剂并烘干,确保孕育剂的粒度为3~8 mm;（2）包内孕育剂加入量由0.6%降至0.3%~0.4%,铁液白口深度较大时,采用0.2%的75Si Fe＋0.15%的Si-Ba复合孕育处理;（3）在直浇道设置过滤器,防止熔渣进入型腔;（4）将铸件初浇温度提高10~20℃,保证末浇温度为1 340℃。生产结果显示：铸件的皮下气孔缺陷问题得到解决,废品率由30%降至5%以内。The structure of the casting and production was introduced. The causes of wet clay sand iron casting pinhole defects was analyzed by using scanning electron microscopy and energy dispersive spectroscopy. The following improvements were taken：（1）Filtering and drying crushing inoculant to ensure that the particle size was 3 ~8 mm.（2）The inoculant package amount was dropped from 0.6% to 0.3%~0.4%. Use 0.2% amount of 75 Si Fe＋0.15% Si-Ba composite inoculation when chill depth of liquid was deep.（3）Set up filters in the sprue to prevent slag flashing into the cavity.（4）The beginning of the casting pouring temperature increased 10 ~20 ℃,to ensure that at the end of pouring temperature was 1 340 ℃. Production results shown：the casting pinhole defect problem was resolved and the rejection rate dropped from 30% to less than 5%.

关 键 词：灰铸铁 皮下气孔 孕育剂 熔渣 

分 类 号：TG250.6[金属学及工艺—铸造]