中文摘要：

研究加入稀土Ce对Al4.5Cu合金流动性、凝固收缩、微观组织和热裂倾向的影响。结果表明,适量稀土Ce的加入,降低金属液的黏度,提高合金流动性,减少金属在凝固过程中的收缩,抑制合金枝晶化的趋势,改善铸造合金的微观组织,净化合金,提高合金的导热率,明显地减少合金的热裂倾向。稀土Ce加入量为4%时,Al4.5Cu合金流动性最佳、凝固收缩量最小、合金晶粒组织细化圆整,同时其热裂倾向最小。

英文摘要：

The effects of adding rare earth Cerium on alloy fluidity,solidification shrinkage,microstructure and hot tearing trend of Al4.5Cu alloy are investigated.The results show that by addition of proper rare earth cerium,a series of effects occur,including the reduction of alloy viscidity,the increase of liquidity,the decreasing shrinkage during the solidification of the metal liquid,the restrained trend of alloy dendrite,the improved microstructure of the casting alloy,the purified alloy,the enhanced thermal conductivity,and the remark decrease of hot tearing trend of Al4.5Cu alloy.With about 4% of rare earth cerium being added to Al4.5Cu alloy,the fluidity of Al4.5Cu alloy is optimal,and the volume shrinkage is the least.At the same time,the grain of the alloy is refined,round and the alloy has the lowest hot tearing trend.