摘要
研究了电极压力、焊接电流、焊接时间和脉冲回火对1 000 MPa级高强结构钢点焊接头显微组织和力学性能的影响。结果表明:随着电极压力和焊接电流增大,接头熔核直径均表现为先增加而后减小的特征;在电极压力为2.8 kN和焊接电流为8.0 kA时接头产生飞溅;随着焊接时间的增加,接头熔核直径呈现逐渐增加的趋势;当电极压力3.4 kN、焊接电流7.5 kA、焊接时间为16 cyc时,接头熔核直径较大,马氏体组织较为细小,硬度较高,此时接头承受的拉剪力可达13.0 kN,具有较高的抗剪强度;经过1次脉冲回火和2次脉冲回火后接头承受的最大拉剪力分别为13.8 kN和14.2 kN,相较于未脉冲回火的点焊接头分别提高了6.15%和9. 23%。
The effects of electrode pressure,welding current,welding time and pulse tempering on the microstructure and mechanical properties of 1 000 MPa grade high strength steel structure spot welded joint were studied.The results show that with the increase of the electrode pressure and welding current,the nugget diameter of the spot welded joint increases first and then decreases,at the electrode pressure of 2.8 kN and the welding current of 8.0 kN,the spot welded joint has splash.With the increase of the welding time,the diameter of the spot welded nugget is increased gradually,at the electrode pressure of 3.4 kN,welding current of 7.5 A and welding time of 16 cyc,the nugget diameter of spot welding joint is larger,the martensite structure is thin,the hardness is higher,the tensile shear force reaches 13.0 kN,the joint strength is higher.After 1 times pulse tempering and 2 times pulse tempering,the maximum tensile shear strength of the spot welded joint is 13.8 kN and 14.2 kN,respectively,which is 6.15%and 9.23%higher than that of the non-pulse tempered joint.
作者
张玉菊
陈颖
张广峻
谢剑
Zhang Yuju;Chen Ying;Zhang Guangjun;Xie Jian(Department of Engineering,Xingtai Polytechnic College,Xingtai 054000,Hebei,China;School of Materials Science and Engineering,Jilin University,Changchun 130012,China)
出处
《焊接》
2018年第9期26-30,66,共6页
Welding & Joining
关键词
电极压力
焊接电流
焊接时间
脉冲回火
点焊
electrode pressure
welding current
welding time
pulse tempering
spot welding
