摘要
新一代超高强Q&P淬火延性钢在具有高强度的同时具有较好的断后伸长率,在车身制造中具有广阔的应用前景.然而在对镀锌Q&P980钢进行电阻点焊试验后,在焊接接头中发现了表面裂纹,前期研究表明该表面裂纹是由液态金属脆化机制所引起的,即钢板在液态锌和应力的共同作用下发生的沿晶界开裂.结果表明,点焊中的工艺参数,包括焊接电流、焊接时间及电极压力、以及加工条件,包括电极端面形状、加压模式、电极对中度均会对接头中的液态金属脆裂纹产生不同程度的影响,因此可以通过调整工艺参数及加工条件来降低裂纹的敏感性.
The new generation ultrahigh strength Q&P(Quenching and Partitioning)steel owns both high strength and fine ductility,it has wide application prospect in automobile industry.However,after carrying out resistance spot welding experiment on the galvanized high strength Q&P980 steel plates,cracks were detected on the surface of joint,former researches showed that the cracks were caused by liquid metal embrittlement(LME),that was the steel plates were intergranular fractured under the effect of liquid zinc and stress.Experiment results indicated that process parameters(including welding current,welding time and electrode force)and process conditions(including electrode morphology,pressure mode and electrode alignment)were found to have influence on the LME cracks of joints.Thus,there is a possibility to reduce the crack sensibility by adjusting the process parameters and conditions.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2018年第7期37-41,共5页
Transactions of The China Welding Institution
基金
国家重点研发计划资助(2017YFB0304400)
关键词
高强钢
电阻点焊
液态金属脆
裂纹
high strength steel
resistance spot welding
liquid metal embrittlement
crack
