研究了添加不同含量的稀土元素La对7055高强度铝合金的铸态组织和力学性能的影响。实验结果表明,稀土元素La对铝合金组织有明显的细化作用,添加适量的稀土元素能够细化铸造铝合金的组织,改善合金的力学性能。但添加过量的稀土元素不仅使合金的晶粒变得粗大,而且使合金的力学性能恶化。 The effects of different content of La on the as-cast microstructure and mechanical properties of 7055 high strength aluminum alloy were studied. The experimental results show that the rare earth element La has obvious thinning effect on the aluminum alloy. Adding appropriate amount of rare earth elements can refine the microstructure of the cast aluminum alloy and improve the mechanical properties of the alloy. However, adding an excessive amount of rare earth elements not only coarsened the grains of the alloy but also deteriorated the mechanical properties of the alloy.