摘要
在厚1.2 mm的08Al与厚1.0 mm的65Mn异种材料的点焊过程中,为了减少可淬硬钢65Mn在焊接过程中所形成的缺陷以及获得优质的异种材料的点焊接头,对双脉冲点焊工艺进行了试验研究。详细分析了熔核的微观组织,测定了熔核直径和硬度分布,并对接头进行了剪切及拉伸试验。实验结果表明,当采用焊接压力3 800 N,一次脉冲电流7.7 kA,通电时间0.24 s;二次脉冲电流4.6 kA,通电时间0.7 s的点焊工艺时,可使点焊熔核得到充分回火,熔核中心未出现二次淬硬组织。其硬度值约HV400。点焊接头的抗拉伸载荷1 380 N,抗剪载荷3 580 N,塑性比38.5%,综合机械性能符合使用要求。
During the dissimilar materials spot welding of 08Al with thickness of 1.2 mm and 65Mn with thickness of 1.0 mm,in order to reduce the welding defects of 65Mn and obtain the high quality nugget,in this article,the process of two-pulse current spot welding is studied.The microstructure of the spot welded joint is analyzed in detail,and the diameter and microhardness of the nugget are measured,then the tensile shear experiment is carried out.The results show that in the conditions of the welding pressure with 3 800 N,the first current with 7.7 kA and lasting 0.24 s,the second current with 4.6 kA and lasting 0.7 s,the joint is tempered adequately and there is no second quench hardening microstructure in the centre of nugget,the microhardness of which is about 400 HV.The resisting tensile load of spot welded joint is 1 380 N,the resisting shearing load of which is 3 580 N and the plasticity ratio of which is 38.5%,and the mechanical properties meet the application requirements
出处
《电焊机》
北大核心
2010年第10期37-40,共4页
Electric Welding Machine
关键词
08Al
65Mn
电阻点焊
组织
性能
08Al
65Mn
resistance spot welding
microstructure
properties
