后扭转梁总成开裂分析  

Cracking Analysis of Rear Torsion Beam Assembly

作　　者：张骁杰 贲显力 李卫华[1] 王冲[1] 袁超 王斌[1] ZHANG Xiaojie;BEN Xianli;LI Weihua;WANG Chong;YUAN Chao;WANG Bin(Automotive Engineering Technical Center of Hebei,Research&Development Center of Great Wall Motor Co.,Ltd.,Baoding Hebei 071000,China)

机构地区：[1]长城汽车股份有限公司技术中心河北省汽车工程技术研究中心

出　　处：《汽车零部件》2019年第10期82-85,共4页Automobile Parts

摘　　要：针对某SUV车型后扭转梁总成开裂问题,采用SEM、元素含量、金相和显微硬度等方法系统地分析后扭转梁总成开裂的原因。分析结果表明零件开裂为疲劳开裂。焊接接头过热区和正火区材料性能差异较大,耐久试验中材料变形不均易产生应力集中,且焊接质量不佳是造成扭转梁总成失效的原因。最后针对此类失效给出相应的解决措施。Aiming at the cracking of the rear torsion beam assembly of a sport utility vehicle,the cracking causes of the rear torsion beam assembly were systematically analyzed by means of scanning electron microscope,elemental analysis,metallography and microhardness.The analysis results show that the cracking of part is fatigue cracking,and the material properties in coarse grain heat affected zone and inter-critical heat affected zone of welded joints are much different.The uneven deformation of materials in durability test is prone to stress concentration,and the poor welding quality are the reasons for the failure of the torsion beam assembly.Finally,the corresponding solutions were given for this kind of failure.

关 键 词：后扭转梁总成 疲劳开裂 低温焊接 焊接缺陷 

分 类 号：TG441.7[金属学及工艺—焊接]