【作者】 李志刚； 李晓东； 马鸣图； 熊云奇； 卢海波； 惠卫军；

【Author】 LI Zhigang~1 LI Xiaodong~2 MA Mingtu~1 XIONG Yunqi~3 LU Haibo~3 HUI Weijun~4(1 China Chongqing Automobile Restarch Institute; Chongqing 400039; 2 Logistics Engineering Institute,Chongqing 400016; 3 Dongfeng Auto Co. Technological Research Institute,Shiyan 442001; 4 Central Iron and Steel Research Institnte, Beijing 100083)

【机构】 重庆汽车研究所； 后勤工程学院； 东风汽车集团公司工艺研究所； 北京钢铁研究总院；

【摘要】 对14.9、12.9级高强度螺栓在不同的应力水平。不同表面状态下,进行了延迟断裂试验。结果表明:14.9、12.9级高强度螺栓在原始表面状态下,一般在20h左右即发生断裂;经涂装后,其抗延迟断裂的时间显著延长,达到或接近标准要求;断口的形貌以穿晶的准解理+微坑为主。更多还原

【Abstract】 Delayed fracture characteristis of 14.9 and 12.9 grad high strenth bolts were investigated. The tests of delayed fracture for 14.9 and 12.9 grad high strength were carried under the various stress level and the various surface conditions. The results show that the 14.9 and 12.9 grad high strength bolts will occur fracture in the about 20h. But after coating surface, the ability for resisting to delayed fracture will be obviously increased and will. attain to or near to standed requirement. The fracture structure is quasi-cleavage plus micro-pits.更多还原