采用宏观及显微分析、能谱分析、密度测试、硬度试验等方法，对某AZ40M镁合金锻件低倍试片上的不规则形状缺陷进行了分析。结果表明：该不规则缺陷为铝、锰、铁元素组成的化合物偏析，属于区域性偏析；该偏析对材料的局部密度和硬度均匀性均有影响；同时由于该区域含有大量的铁元素，其耐蚀性能也大大降低。

By means of macroscopic and microscopic analysis, energy spectrum analysis, density test and hardness test, the anomaly-defect in the macrostructure specimen of AZ40M magnesium alloy forging was analyzed. The results show that the anomaly-defect was segregation of compounds composed of elements of Al, Mn and Fe, and it belonged to regional segregation. The segregation had influence on the local density and hardness uniformity of the material. At the same time, due to the large amount of Fe element in the region, the corrosion resistance was also greatly reduced.