双相钢点焊熔核界面撕裂分析  

Analysis of interfacial fracture of resistance spot welding of dual-phase steels

作　　者：张小云[1] 张延松[1] 来新民[1] 陈关龙[1] 

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《焊接学报》2008年第8期45-48,共4页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(50575140);高校博士点基金资助项目(20050248028)

摘　　要：双相高强钢电阻点焊快速冷却过程中形成的淬硬马氏体会增加点焊接头脆性,产生熔核界面撕裂问题,降低接头力学性能与低周疲劳寿命。以1.4mm双相钢DP600为例,采用残余在母材上的熔核面积百分比作为衡量电阻点焊熔核界面撕裂程度的评价指标,利用正交试验设计方法,研究不同焊接工艺参数对熔核撕裂程度的影响规律。通过对单因子分析,可知焊接电流对双相钢点焊接头撕裂程度的影响最大;通过交互作用分析,获得了减少焊点界面撕裂程度的最优工艺参数;最后通过试验验证,有效减少和避免焊点界面撕裂发生。The transformed martensite of dual-phase steel during the cooling stage of spot welding can make the weld nugget very brittle and result in interfacial fracture which was inspected by destructive methods. This failure mode can reduce the static strength and fatigue life of the weld. 1.4 mm DP600 sheets were taken as an example, percentage of residual area in the whole nugget is used to evaluate the interfacial fracture magnitude. Then orthogonal test is used to analyze the influence of welding parameters on fracture magnitude. After single factor analysis, it can be concluded that the welding current is the most important factor that influence the welding magnitude. Using interaction analysis, the optimized welding parameters can be obtained. Experiments are conducted to validate that the modified welding parameters can reduce interfacial fracture magnitude effectively.

关 键 词：电阻点焊 双相钢 界面撕裂 正交试验 

分 类 号：TG438[金属学及工艺—焊接]