球墨铸铁铸件的补缩工艺

Feeding Process of the Ductile Iron Castings

通过分析和总结在生产实践过程中球墨铸铁铸件产生缩孔缩松缺陷以及成功解决办法,对球铁铸件凝固收缩理论提出理解和看法:铸件的补缩及缺陷产生取决于压力,由于球铁的凝固特性使石墨化膨胀和凝固收缩分离,薄壁件截面凝固差异不明显,石墨化膨胀压力无法有效利用,厚大件的截面凝固的差异大,容易实现石墨化膨胀压力的利用。铸造补缩工艺的设计原则就是提供并保持这样的压力,对薄壁要强调外部压力补缩,厚壁则充分利用石墨化膨胀压力自补缩。

By analyzing and summarizing the process of practice in the production of ductile iron castings produced Shrinkage Defects and successful solution.Make to some understand and view of ductile iron castings solidification theory： Feeding a casting depend upon the pressure.For the solidification characteristic of the spheroidal graphite cast iron,the expansion of the graphitization are not synchronized shrink.In thin wall,no function of the the expansion pressure of the graphitization because fewer division of solidification,and the thick wall,the more division with solidification in section,so the expansion and the shrink will be segistration.So the intention of the feeding process disign are supporting and keeping on pressure.The thin wall,pressure shall be supported with others,and the thick wall,the pressure maybe exploit the the the expansion of the graphitization.