机件断裂是危险的失效方式之一,不仅危及人身完全,且对国家财产带来巨大损失。从断裂事例分析开始,进而据此改进产品的设计、材料冶炼和制造工艺,对提高产品质量有重要意义。分析研究断裂的目的,一方面是解决实际问题,防止在运转中机件断裂;另一方面,是探明断裂的机理。机件断裂事例分析研究的方法,主要是用断裂力学知识解决实际问题,并用断口金相分析探明断裂的微观机 Mechanical fracture is one of the dangerous failure modes, which not only endanger people completely, but also bring huge losses to state property. From the analysis of the case of rupture, and then to improve the product design, material smelting and manufacturing processes, to improve product quality is of great significance. Analysis of the purpose of fracture analysis, on the one hand is to solve practical problems, to prevent mechanical fracture in the operation; the other hand, to identify the mechanism of fracture. The method of mechanical fracture analysis is mainly based on fracture mechanics to solve practical problems. Fracture micro-machine