【作者】 路宝玺； 尤兆宏； 关凯书；

【Author】 Lu Baoxi~1 You Zhaohong~1 Guan Kaishu~2 (1.Shanghai SECCO petrochemical Co.,Ltd Shanghai 201507; 2.The key laboratory of safety science of pressurized system,ministry of education,East China University of Science and Technology ShangHai 200237 China)

【机构】 上海赛科石化股份有限责任公司； 华东理工大学承压系统安全科学教育部重点实验室；

【摘要】 采用金相、扫描电镜方法对电子束焊接的乙烯裂解炉管焊缝开裂进行了分析。分析结果显示,电子束焊接过程中形成了垂直柱状晶,焊缝的中心存在明显的交汇线,而裂纹正是在交汇线上形成的。焊缝中心存在大量的碳化物析出物,导致焊缝的脆化,该中心线成为炉管的薄弱部位,抗热疲劳断裂能力、高温抗拉强度和抗高温蠕变断裂能力变差。停车降温引起的炉管收缩拉力加速了焊缝的开裂。更多还原

【Abstract】 the crack occurred at the electron beam weld of ethylene cracking tubes.The failure analysis was carried out by mean of metallography and scanning electron microscope(SEM).The results show that obvious centerline with dendritic crystal at the weld was existence where the crack occurred.Coalescence of carbides is identical at the centerline which results in me brittlement of me weld.Centerline results from electron beam weld is mainly responsible for the crack.Temperature decreases violently during shutting down accelerated me cracks.更多还原