热成形钢点焊接头性能影响因素  

Influencing factors of resistance spot welding performance of press-hardened steel

作　　者：王伟峰[1] 计遥遥[1] 代朋虎 周世龙[1] Wang Weifeng;Ji Yaoyao;Dai Penghu;Zhou Shilong(Technology Center of Ma’anshan Iron and Steel Company,Ma’anshan 243000,Anhui,China)

机构地区：[1]马鞍山钢铁股份有限公司技术中心,安徽马鞍山243000

出　　处：《焊接》2024年第10期67-73,共7页Welding & Joining

摘　　要：【目的】为了研究焊接工艺参数对热成形钢点焊接头性能的影响。【方法】采用正交试验方法,对22MnB5热成形钢点焊接头性能进行了试验研究。【结果】单脉冲焊接工艺条件下,在焊接电流、焊接时间和电极压力3个工艺因素中,焊接电流对点焊接头力学性能的影响程度最大,电极压力的影响次之,焊接时间的影响程度较小。最佳的点焊工艺参数组合为焊接电流8.5 kA,电极压力4 kN,焊接时间525 ms,点焊接头的力学性能表现为最好。【结论】热成形钢点焊接头由母材区、回火区、软化区、临界区和熔核区组成,焊点结合线位置(熔核区)存在严重的应力集中,是热成形钢焊点失效的危险区域。采用多次脉冲焊接,末次脉冲小热输入量可以显著降低接头的应力集中,提升焊点的力学性能。[Objective]The purpose is to study influence of welding process parameters on properties of spot welded joints of hot forming steel.[Methods]The orthogonal test is performed for 22MnB5 press-hardened steel.[Results]The order of priority affecting the mechanical properties of spot weld is welding current,electrode pressure and welding time under the condition of single pulse welding process.The best mechanical properties of the welded joint and the good welding quality can be gotten with the best welding parameters,welding current of 8.5 kA,welding time of 525 ms,and electrode pressure of 4 kN.[Conclusion]The press-hardened steel welded joint consists of the BM area,the tempering area,the softening area,the critical area and the nugget area.There is a serious stress concentration at the welding point joint line(nugget zone),which is a dangerous area for the failure of press-hardened steel welding joints.The last pulse small heat input can significantly reduce the stress concentration of the welding joint and improve the mechanical properties of the joint by using multiple pulse welding.

关 键 词：热成形钢 影响因素 最佳点焊工艺 多次脉冲焊接 

分 类 号：TG453[金属学及工艺—焊接]