焊接电流对铝合金和不锈钢电弧熔钎焊接头性能的影响

Effect of Welding Current on Properties of Aluminum Alloy and Stainless Steel Arc Welding Brazing Joints

通过调整焊接电流成功获得了5052铝合金与304不锈钢电弧熔钎焊对接接头。使用扫描电镜(SEM)观察分析了铝/钢接头微观形貌,研究了焊接电流对接头界面结构及力学性能的影响。研究发现,在最优焊接电流85 A下,接头钢侧界面生成致密的金属间化合物层,其平均厚度为7.97μm,经过能谱仪(EDS)分析确定,界面反应产物为η-Fe_(2)Al_(5)和θ-Fe_(4)Al_(13)相。在拉伸载荷下,85A时获得的接头平均抗拉强度为180.8 MPa,约为铝合金抗拉强度的86%。断裂路径在靠近熔合区的铝合金焊缝处,断裂方式是以韧性断裂为主的混合型断裂。

5052 aluminum alloy and 304 stainless steel arc welding brazing butt joints were successfully obtained by adjusting the welding current. Scanning electron microscope(SEM) was used to observe and analyze the microstructure of the aluminum/steel joints, and the effect of welding current on the interfacial morphology and mechanical properties of the joints was studied. The study shows that under the optimal welding current of 85 A, dense intermetallic compound layer is formed on the interface of the joint at the steel side, and the average thickness is 7.97 μm. It is determined by energy spectrometer(EDS) analysis that the interface reaction product is η-Fe_(2)Al_(5)and θ-Fe_(4)Al_(13)phases. Under tensile load, the tensile strength of the joint obtained at 85 A reaches 180.84 MPa, about 86% of the tensile strength of the aluminum alloy.The fracture path is located at the aluminum alloy weld near the fusion zone, and the fracture mode is a composite fracture dominated by ductile fracture.