某苯乙烯装置中Incoloy 800HT合金高温蒸汽管道主管对接接头开裂原因  

Cracking Cause of Incoloy 800HT Alloy High-Temperature Steam Pipeline Butt Weld in Styrene Plant

作　　者：陈刚 李志峰[2] 路宝玺 杨利军[2] CHEN Gang;LI Zhifeng;LU Baoxi;YANG Lijun(Shanghai SECCO Petrochemical Company Limited,Shanghai 201507,China;China Special Equipment Inspection&Research Institute,Beijing 100013,China)

机构地区：[1]上海赛科石油化工有限责任公司,上海201507 [2]中国特种设备检测研究院,北京100013

出　　处：《机械工程材料》2022年第12期98-102,共5页Materials For Mechanical Engineering

基　　金：国家市场监督管理总局科技计划项目(2021MK169)。

摘　　要：某苯乙烯装置中已使用13 a的Incoloy 800HT合金高温蒸汽管道在定期检验过程中在主管对接接头处发现裂纹,通过拉伸试验、弯曲试验、金相检验和微观形貌观察等方法分析了裂纹产生的原因。结果表明:主管接头在913℃长时服役后在熔合线上有大量析出相,析出相主要是由合金元素铬和钼形成的碳化物;碳化物相的析出导致合金高温力学性能的降低并产生应力集中,蠕变孔洞在析出相附近产生,长时间高温使用下演变为蠕变裂纹。Cracks were found in the regular inspection of Incoloy 800HT alloy high temperature steam pipeline used for 13 a, and the causes of cracks were analyzed by tensile test, bending test, metallographic examination and micromorphology observation. The results show that the tensile and bending specimens both fractured on the weld fusion line. A large number of precipitated phases existed on the fusion line, and the precipitated phases were mainly carbides formed by alloying elements chromium and molybdenum. The phase led to the decrease of high temperature mechanical properties of the alloy and the generation of stress concentration. Creep holes were generated near the precipitated phase and evolved into creep cracks after long-term high temperature use.

关 键 词：Incoloy 800HT合金 熔合线 蠕变裂纹 析出相 

分 类 号：TG172.6[金属学及工艺—金属表面处理]