煤气加热器断裂螺栓的失效分析(英文)  

Failure Analysis of Ruptured Bolts in Coal Gas Heater

作　　者：朱岗 邱艳丽[2] 杨振国[2] 

机构地区：[1]上海石化总厂,上海200004 [2]复旦大学材料科学系,上海200433

出　　处：《复旦学报（自然科学版）》2008年第3期391-397,共7页Journal of Fudan University：Natural Science

摘　　要：对350 MW燃气轮机发电装置煤气加热器盲板上的螺栓断裂的失效机理及其起因进行了系统性的研究.采用一系列的微宏观表征方法,分析其化学组成、金相结构、宏观外形、微观形态和微区的化学结构.试验结果表明:螺栓的失效主要是由其材质不良、表面加工不当、紧固力不合理以及腐蚀环境等共同作用造起的.进一步讨论了螺栓的电偶腐蚀、缝隙腐蚀和应力腐蚀开裂的相关机理,并提出相应的预防措施.The failure mechanisms and causes of the ruptured bolts of blind plate on a coal gas heater of 350 MW gas turbine generating unit were systematically studied. A series of macroscopic and microscopic analysis methods were used to characterize chemical composition, metallographic structure, macroscopic appearance, microscopic morphology and microarea chemical composition of the bolts. The experimental results showed that the failure of the bolts were mainly caused by galvanic corrosion, crevice corrosion and followed stress corrosion cracking, which were resulted from inferior material, unqualified processing quality, and unsuitable fastening force and corrosive environment. The relevant mechanisms on crevice corrosion and stress corrosion cracking of the bolts were carefully discussed and countermeasures for preventing the bolts were also proposed.

关 键 词：螺栓 不锈钢 电偶腐蚀 缝隙腐蚀 失效分析 

分 类 号：TB302[一般工业技术—材料科学与工程]