铝合金高压开关壳体铸造针孔形成原因及解决措施  

Formation Causes of Pinholes in Aluminium Alloy High Voltage Switch Housings and Prevention Measurements

作　　者：赵丽娟 ZHAO Li-juan(Changzhou Institute of Industry Technology, Changzhou 213164, Jiangsu, China)

机构地区：[1]常州工业职业技术学院,江苏常州213164

出　　处：《铸造》2019年第5期516-518,共3页Foundry

摘　　要：铝合金高压开关壳体形状复杂,采用低压砂型铸造时,端面处有针孔缺陷。分析认为,针孔缺陷形成的原因是铸件内浇口设计在端面处,凝固时冷却缓慢,导致氢气析出,阻碍铝液补缩,形成气缩孔。通过对铸造工艺优化,加快壳体端面部位冷却速率,解决了铸件针孔缺陷。Aluminium alloy high voltage switch housings produced using low pressure sand casting had pinholes defect at the end face. Through experimental analysis, it was found that the pinholes defect at the end face is related to the layout of ingates. The ingates at the end face resulted in the low cooling rate at the end face region during the solidification, which caused the hydrogen precipitation and the formation of gas porosity. Placing chills near the defects position and decreasing the size of ingates can quicken the cooling rate of the end face,preventing hydrogen precipitation. Therefore, the pinhole defect could be eliminated.

关 键 词：高压开关壳体 针孔 铸造工艺 气缩孔 

分 类 号：TG292[金属学及工艺—铸造]