不同焊丝2A14铝合金TIG焊接头微观组织和力学性能对比分析

Comparative Analysis of Microstructure and Mechanical Properties of TIG Welding Joint of 2A14 Aluminum Alloy with Different Welding Wires

摘要: 分别采用BJ-380D焊丝和BJ-380A焊丝开展了2A14-T6铝合金的TIG焊接试验，对比研究BJ-380D焊丝和BJ-380A焊丝对焊接接头组织、抗拉强度和硬度的影响。结果表明：两种焊丝接头焊缝区均为典型的铸态枝晶组织，焊丝Zr、V、Cr等微合金成分的添加使得BJ-380D焊丝接头焊缝区微观组织比BJ-380A焊丝焊接接头的更加细小，同时接头抗拉强度、伸长率及显微硬度也得到一定程度的提高。BJ-380D焊丝中添加的Be元素，起到了控制焊缝中Al₂O₃夹杂，抑制焊缝气孔缺陷的作用。相同焊接条件下，BJ-380D焊丝焊缝组织中的微观气孔大幅降低。

Abstract: TIG welding test of 2A14-T6 aluminum alloy were carried out by using BJ-380D and BJ-380A welding wires, respectively. The effects of BJ-380D and BJ-380A welding wires on the microstructure, tensile strength and hardness of the welded joints were discussed.The results show that typical cast dendrite is obtained in the weld zone of the joints with the two welding wires. Zr, V, Cr elements added in BJ-380D welding wire can refine the microstructure of weld zone, and the mechanical properties of the welded joint increase in a certain extent.Be element added in BJ-380D welding wire can reduce Al₂O₃ inclusions, and inhabits the pore defect in the weld. Under the same welding conditions, the micro-pores in the weld zone with BJ-380D welding wire are greatly reduced.