TIG-拉弧复合热源铝合金螺柱焊接方法

Aluminum stud welding using TIG-arc hybrid heating source

针对中大直径铝合金螺柱焊接过程中出现气孔、未熔合、热裂纹等缺陷及焊接接头性能不良问题,以直径16 mm螺柱为研究对象进行了铝合金螺柱焊方法和工艺的探索性研究.提出了TIG-拉弧复合热源焊接技术,在焊前对铝螺柱采取预浸镀一层锌镍的处理方法,整个施焊过程处于惰性气体保护的状态下.力学性能检测得到接头抗剪强度能够达到128 MPa,其强度系数为70%以上.最佳焊接工艺参数为:预热150℃、焊接电流650 A、焊接时间1 000 ms.结果表明,铝板焊前TIG预处理、螺柱预浸镀锌镍等都能够有效的提高螺柱焊接接头力学性能,并且改善焊缝组织.

Aiming at the problematic issues occured in stud welding in large diameter component,such as gas pore,hot crack and incomplete fusion and poor joint,a welding technology was proposed using TIG-Arc hybrid heating sourceand conducted on Φ16 mm aluminum stud welding. Before the welding of aluminum stud,immersion plating of Zn-Ni layer was applied on the aluminum stud. The whole welding process was protected with inert gas. The shear strength of joint can reached 128 MPa and the strength coefficient of the joint is above 70%. The optimum welding parameters are,preheating temperature of 200 ℃,welding time of 1000 ms,welding current of 650 A. The experimental results also show that the pretreatment of aluminum by TIG and Zn-Ni plating of can effectively improve the mechanical properties and the microstructure of the joint.