采用金相显微镜、扫描电镜、硬度测试以及电子拉伸等手段,对比研究了Y、Nd和Gd三种稀土元素对镁合金铸态和热处理后显微组织与性能的影响规律。结果表明,三种稀土元素加入合金中,均可以细化组织,提高合金的强度和硬度,特别是经过时效热处理后合金的强度有明显的提高。相同条件下,稀土Nd的晶粒细化作用及强化效果最显著。 The effects of Y, Nd and Gd on the microstructure and properties of magnesium alloy after as-cast and heat treatment were studied by means of metallographic microscope, scanning electron microscope, hardness test and electronic stretching. The results show that the three rare earth elements added to the alloy, can refine the organization to improve the strength and hardness of the alloy, especially after aging heat treatment significantly improved the strength of the alloy. The same conditions, the rare earth Nd grain refinement and strengthening the most significant effect.