摘要
采用扫描电镜观察、化学成分及金相检验等方法对高强度螺栓断裂的原因进行了分析。结果表明,螺栓基材的芯部显微组织中含有一定量的贝氏体,降低了零件的强度,导致在承受外力作用时,过早在应力集中的螺栓头根部产生疲劳裂纹。在交变应力和腐蚀介质的共同作用下,造成疲劳裂纹不断向内扩展。当个别螺栓的有效承载截面减小至强度不足时引起断裂,剩余螺栓承受载荷加大,加速产生腐蚀疲劳断裂。
The reason on fracture of high strength bolt was analyzed by means of SEM observation,composition analysis and metallographic test.The results show that there is a centain amount of bainite in microstructure at the core of the bolt substrate,which reduced the strength of bolt,leading to produce too early the fatigue crack at the root of bolt head of stress concentration when subjected to external forces.Under the joint action of alternating stress and corrosion medium,the fatigue crack keeps expanding inward.The bolt would be finally fractured when the effective bearing secsion of individual bolts is reduced to the strength insufficient to be to cause fracture,and the other bolts subjected more load to accelerate the corrosion fatigue fracture.
作者
王鑫
孙耀明
彭晓华
江俊灵
张轶梁
梁成劲
唐武飞
陈寿
WANG Xin;SUN Yao-ming;PENG Xiao-hua;JIANG Jun-ling;ZHANG Yi-liang;LIANG Cheng-jin;TANG Wu-fei;CHEN Shou(Shenzhen 863 New Material and Technology Co.,Ltd.,Shenzhen Guangdong 518117,China;Shenzhen Beauty Star Co.,Ltd.,Shenzhen Guangdong 518117,China)
出处
《热处理技术与装备》
2019年第6期39-42,共4页
Heat Treatment Technology and Equipment
基金
深圳市科技攻关项目(JSGG20170822140852612)
关键词
高强度螺栓
贝氏体
腐蚀疲劳
high strength bolt
bainite
corrosion fatigue
作者简介
王鑫(1985-),女,硕士,工程师,从事材料方面的分析研究工作;通信作者:孙耀明,联系电话:13751034189,E-mail:petervivi@qq.com。
