热冲压高强钢点焊接头质量评价  

Quality evaluation of spot welded joints of hot stamping high strength steel

作　　者：郝素锋[1] 姜超[1] 陈树君[2] 龚金龙[2] 

机构地区：[1]机械科学研究总院先进制造技术研究中心,北京市100083 [2]北京工业大学机电学院,100124

出　　处：《焊接》2015年第2期48-50,71,共3页Welding & Joining

摘　　要：热冲压高强钢由于其独特的材料特性及点焊热循环的瞬时高温作用,致使点焊接头存在严重的不均匀性,接头更倾向于以界面断裂方式失效,采用传统的接头评价标准存在严重的评价不足问题。针对热冲压高强钢点焊接头质量评价问题,建立热冲压高强钢焊点熔核区球面模型,通过对界面断裂和熔核拔出两种失效方式下的接头应力分析,获得热冲压高强钢焊点临界失效熔核直径评价标准,并在1.2 mm,2 mm厚热冲压高强钢板上通过验证。结果表明,该临界失效熔核直径评价标准能够准确评价22MnB5钢板点焊接头失效。The spot welded joints of hot stamping high strength steel are more inclined to fail as the failure mode of interfacial fracture because of its unique material properties and the instantaneous high temperature of the spot welding thermal cycle.Because the microstructures of the joint become uneven,the welded joint quality cannot be evaluated exactly based on the traditional evaluation standard.The spherical model of welded joint of hot stamping high strength steel was founded to evaluate the spot welding quality.By analyzing the stress analysis in the joint at failure modes of high strength steel joint,the evaluation standard of the critical diameter of nugget was obtained to predict the failure.The experiments showed that the new critical formula can accurately evaluate failure of the welded joints of hot stamping high strength steel.

关 键 词：热冲压高强钢 电阻点焊 界面断裂 熔核拔出 质量评价 

分 类 号：TG444[金属学及工艺—焊接]