铸铁件缩孔和缩松缺陷防止方法及应用实例

Methods to Prevent Shrinkage Cavity and Porosity Defect of Iron Castings and Their Application Examples

缩孔、缩松是铸铁件的常见缺陷,对这类缺陷的控制标准取决于铸件的功能要求。以汽车铸件为例,介绍了防止缩孔、缩松缺陷的几种常用方法,包括:(1)冒口补缩;(2)熔炼浇注工艺调整控制;(3)冷铁激冷;(4)用冷却筋、散热片局部加速冷却;(5)采用导热率高的型砂、芯砂局部加速冷却;等。同时还介绍了这些方法的原理、使用范围和选择原则。

Shrinkage cavity and porosity are the common defects of the iron castings. The limitation standard of these defects depends on the function requirements of the castings. Taking some automotive castings produced by author＇s company as examples, the methods used usually to prevent the shrinkage defects were introduced including： （ 1 ）riser feeding; （2）melting and pouring process adjustment and control; （3）chilling with iron denseners; （4）locally accelerating cooling with cooling ribs and fins; （5）locally accelerating cooling with high thermal conducting molding or core sand. And the effect principle, application range and choice of above methods were described.