某汽车变速箱316L不锈钢过滤网在服役期间出现多处断裂。通过宏观分析、断口分析、金相检验及成分分析、微观分析等方法对过滤网的断裂原因进行了分析。结果表明：该316L不锈钢过滤网的断裂模式为疲劳断裂。网丝在拉拔工艺中表面产生了分层、划痕及其近表面的硬质夹杂颗粒等缺陷，集成制网时在网丝交叉处产生了加工硬化，在二者的共同作用下导致过滤网发生疲劳断裂。

The 316L stainless steel strainer screen of an automobile gearbox fractured in several places during its service. The fracture causes of the strainer screen were analyzed by means of macro analysis, fracture analysis, metallographic examination, composition analysis and micro analysis. The results show that the fracture mode of the 316L stainless steel strainer screen was fatigue fracture. During the drawing process, there were some defects on the surface of wire, such as delamination, scratch and hard inclusion particles near the surface. Work hardening occurred at the intersection of wire mesh during integrated mesh making. Under the joint action of the both sides, the strainer screen occurred fatigue fracture.