采用光学显微镜和扫描电镜对使用过程中开裂的大型低合金钢空心磨球残体进行了组织观察分析，测定 了其硬度和冲击韧性。 结果表明，大型低合金钢空心磨球组织中存在夹杂物和缩松，以及组织转变不均匀和针状铁素 体，造成冲击韧性明显偏低和硬度偏高，使空心磨球运行过程中发生开裂。提出了防止大型低合金钢空心磨球运行过程 开裂的建议措施。

Optical microscopy and scanning electron microscopy were used to observe and analyse the microstructures of large hollow grinding ball residues made of low-alloy steel that cracked during use, and their hardness and impact toughness were determined. The results show that inclusions and microscopic shrinkage cavities exist in the microstructures of large low alloy steel hollow grinding balls, as well as uneven and thorough microstructure transformation, resulting in significantly lower impact toughness and higher hardness, causing cracking of the hollow grinding balls during operation. Measures to prevent cracking of large low alloy steel hollow grinding balls have also been proposed.