ZA—27合金铸件底缩的控制和防止

The Control and Prevention of the Underside Shrinkage in ZA-27 Alloy Casting

对ZA—27合金砂型铸件产生底面收缩(底缩)进行了试验研究。试验表明:铸件顶部的含铝量比底部多得多,这是铝的宏观偏析,它导致底缩的形成。本文提出了控制和防止底缩的方法。

The underside shrinkage in ZA-27 alloy sand mold castings has been studied. The experimental results show that the content of aluminum in the top of the casting is much more than in the bottom and it is such a macrosegregation of aluminum during solidification that leads to the formation of the underside shrinkage. The mathods for control and prevention of this kind of defect are also given in this paper.