零件的断裂往往导致事故,不仅损坏机器,甚至危及人身安全。影响零件断裂的因素很多,有原材料的质量问题,有铸、锻、热处理工艺问题,有冷加工和装配质量的影响,有负荷条件工作环境、设计选材和使用操作不当等原因。所以对失效的构件分析,必须深入现场调查研究,从失效的构件宏观和显微组织结构研究出发,综合化学成份, Breaking of parts often leads to accidents, not only damaging the machine, but also endangering personal safety. There are many factors that affect the breakage of parts. There are quality problems of raw materials, casting, forging, heat treatment process problems, the impact of cold working and assembly quality, working conditions of load conditions, design selection and improper operation. Therefore, the failure of component analysis, we must in-depth field investigations and studies, starting from the macroscopic failure of the structure and microstructure research, integrated chemical composition,