稀土合金变质对高碳当量灰铸铁结晶过程及工艺性能的影响

Process and Crystallization of High Carbon Equivalent Gray Cast Iron Modified by Rare Earth Alloy

系统综述了稀土合金变质剂对高碳当量灰铸铁工艺性能的影响,并从热分析、晶格常数和共晶团的角度分析了高碳当量灰铸铁在稀土合金变质条件下的结晶过程。实验结果表明,用适量的稀土合金对高碳当量灰铸铁进行变质,可降低白口倾向,有效细化石墨,使共晶团数量增加,同时造成一定程度的晶格畸变,产生了良好的孕育效果,并且在使高碳当量灰铸铁力学性能得到一定程度提高的同时,保留了其良好的铸造性能。

The effect of rare earth alloy modification on technological performances in high carbon equivalent gray cast iron was summarized systematically, and the crystallization process of high carbon equivalent gray cast iron with a certain amount of rare earth alloy modification was analyzed from viewpoint of thermal theory, crystal lattice and eutectic cell. Experiment results show that the adding right amount of rare earth alloy modification in high carbon equivalent gray cast iron can reduce the chilling tendency, refine graphite effectively, and increase the number of eutectic cell. Meanwhile, it can bring about crystal lattice distortion and perfect inoculation efficiency. As result, it can improve the mechanical properties of high carbon equivalent gray cast iron with retaining its perfect castability.