20Cr1Mo1VNbTiB钢高温紧固螺栓失效分析  

Failure analysis of high temperature fastening bolt of 20Cr1Mo1VNbTiB steel

作　　者：黄江 牟申周 王静 陶亮 黄桥生 王学[3] Huang Jiang;Mou Shenzhou;Wang Jing;Tao Liang;Huang Qiaosheng;Wang Xue(CHN Energy Changyuan Wuhan Qingshan Co-Generation Co.,Ltd.,Wuhan Hubei 430080,China;Wuhan Branch,China Energy Science and Technology Research Institute Co.,Ltd.,Wuhan Hubei 430077,China;School of Power and Mechanics,Wuhan University,Wuhan Hubei 430072,China)

机构地区：[1]国能长源武汉青山热电有限公司,湖北武汉430080 [2]国家能源集团科学技术研究院有限公司武汉分公司,湖北武汉430077 [3]武汉大学动力与机械学院,湖北武汉430072

出　　处：《金属热处理》2023年第8期286-290,共5页Heat Treatment of Metals

基　　金：国家自然科学基金(52174370)。

摘　　要：某超临界机组用20Cr1Mo1VNbTiB钢高温螺栓出现了早期断裂,对断裂的宏观和微观特征进行了观察,分析了螺栓老化状况,探讨其失效原因。结果表明,20Cr1Mo1VNbTiB钢螺栓经高温运行后,碳化物聚集长大不明显,抗拉强度和硬度没有明显下降,但冲击性能明显降低,可见螺栓断裂失效与老化无关。装配时的预紧力过大,加速了螺栓的蠕变损伤,根据断口形貌判定其断裂性质为高温蠕变断裂。A high-temperature bolt made of 20Cr1Mo1VNbTiB steel for a certain supercritical unit was early fractured.The macroscopic and microscopic characteristics of the fracture were observed,the aging condition of the bolt was analyzed,and the failure reasons were discussed.The results show that after running at high temperature,the aggregate growth of carbides in the bolt is not obvious,the decrease of tensile strength and hardness is not significant,but the decrease of impact absorbed energy is obvious,which means that the bolt fracture failure is not related to the aging.Excessive preload during the bolt assembly accelerates its creep damage.According to the fracture morphology,it is determined that the fracture belongs to high temperature creep rupture.

关 键 词：20Cr1Mo1VNbTiB钢 螺栓 断裂 组织 力学性能 

分 类 号：TG162.84[金属学及工艺—热处理]