运用SEM对聚醚酰亚胺注射成型制品的微观结构进行了分析,找出了制品应力开裂的原因。对制品脆断面的SEM分析可以看出,细微的银纹和熔融料流注射充模过程的流动波纹,有助于正确判断影响制品质量的工艺因素。工程塑料的熔融行为对成型加工至关重要,正确的工艺设置需要对熔融行为进行测试。指出了影响PEI注塑件应力的成型技术的关键因素。 The microstructure of polyetherimide injection molded product was analyzed by SEM, and the reason of stress cracking was found out. SEM analysis of the brittle section of the product shows that the flow ripples during the injection molding process of the fine silver grain and melt stream help to correctly judge the technological factors that affect the product quality. The melting behavior of engineering plastics is crucial to the forming process, and the correct process settings require testing of the melting behavior. The key factors affecting the forming technology of PEI injection molded parts are pointed out.