摘要
通过对路试断裂螺栓套进行断口和能谱分析,确定断裂失效模式为延迟性开裂,并进一步从金相和硬度方面分析认为,不当的焊接工艺导致螺栓套形成中碳马氏体,硬度偏高是延迟开裂的主要原因。通过改进螺栓套焊接工艺解决了螺栓套硬度偏高问题,改进后再次进行金相和硬度检验,螺栓套马氏体含量和硬度均降低到合理范围内,螺栓套延迟开裂问题得到了有效控制。
Based on the analysis of the fracture surface and energy spectrum of the fractured bolt sleeve in the road test,it is determined that the fracture failure mode is delayed cracking.Furthermore,from the aspects of metallography and hardness,it is found that improper welding process led to the formation of medium carbon martensite in the bolt sleeve,and high hardness is the main reason for delayed cracking.The problem of high hardness of the bolt sleeve is solved by improving the welding technology of the bolt sleeve.The improved bolt sleeve is subjected to metallographic and hardness testing again.The martensite content and hardness of the improved bolt sleeve are reduced to a reasonable range.The problem of delayed cracking of the bolt sleeve is effectively controlled.
作者
王迪
唐刚
梁鹏
周俊
周盼泉
Wang Di;Tang Gang;Liang Peng;Zhou Jun;Zhou Panquan(BYD Auto lndustry Company Limited,Shenzhen 518118)
出处
《汽车工艺与材料》
2025年第8期36-40,共5页
Automobile Technology & Material
关键词
螺栓套
焊接
延迟开裂
马氏体
Bolt sleeve
Welding
Delayed cracking
Martensite
