85Cr18Mo2V进气门断裂失效机理分析  

Analysis on Fracture Failure Mechanism of 85Cr18Mo2V Intake Valve

作　　者：胡巍[1] 樊湘芳[1] 王媛妮[1] 龚仁政 

机构地区：[1]南华大学机械工程学院,湖南衡阳421001

出　　处：《热加工工艺》2016年第6期256-257,260,共3页Hot Working Technology

基　　金：衡阳市科学技术发展计划项目(2013k J03)

摘　　要：利用JSM-6490LA型扫描电镜、GX51型奥林巴斯倒置金相显微镜及TH320全洛氏硬度计等仪器,对85Cr18Mo2V进气门的断裂失效样件进行宏观形貌和微观组织观察、化学成分检测和硬度测试,探讨进气门断裂失效机理。结果表明:当原材料C、Si、O含量偏高,或后续热加工工艺不当,会使组织成分不均匀,冲击韧性和疲劳强度降低,进气门的脆性增加,导致其在恶劣的工作环境下发生高周疲劳断裂。By JSM-6490LA SEM, Olympus GX51 stereomicroscope and TH320 Rockwell apparatus, the macro -morphology and microstructure observation, chemical composition testing and hardness testing of 85Crl 8Mo2Vintake valve were carried out. The fracture failure mechanism of intake valve was discussed. The results show that under high content of C, Si and O in raw material or improper subsequent hot working technology, the microstructure composition is uneven, and then, the impact toughness and fatigue strength reduce, the brittleness of intake valve increases. At last, high cycle fatigue fracture appears in 85Crl 8Mo2V intake valve under bad working condition.

关 键 词：85Cr18Mo2V 进气门 高周疲劳 

分 类 号：TG111.91[金属学及工艺—物理冶金]