【摘要】 使用UN-100交流电阻对焊设备，焊接直径为10 mm的Q235低碳钢和6061铝合金棒材。通过预试验确定工艺参数范围，进行多次正交试验找到相对优异的焊接工艺参数，利用金相显微镜、显微硬度计和万能试验机研究了焊接时采用的端面形式、保护气及过渡层金属对铝钢棒材接头组织与性能的影响。结果表明，当焊接功率为41 kW、焊接时间为1.1 s、加压时间为0.2 s时，可获得性能优良的铝钢对焊焊接接头，抗拉强度最大可达149 MPa，约为6061铝合金电阻对焊接头抗拉强度的77%。此外，采用圆锥台端面、通入氩气保护、添加锌作为中间过渡层会使得焊接接头力学性能提高。当采用圆锥台端面直径为7 mm时，其抗拉强度可达到172 MPa，约为6061铝合金电阻对焊接头的89%，添加中间过渡层金属Zn会使得焊接接头抗拉强度以及硬度值有所提高，添加Cu过渡层未能有效抑制界面Al-Fe金属间化合物的生成，使得焊接接头的抗拉强度有所下降。更多还原

【Abstract】 UN-100 AC resistance butt welding equipment was utilized to weld Q235 low carbon steel and 6061 aluminum alloy bar with a diameter of 10 mm. The range of process parameters was determined through preliminary experiments, and several orthogonal experiments were conducted to understand relatively excellent welding process parameters. The effects of end surface form, protective gas and transition layer metal on the microstructure and properties of aluminum-steel bar joints were investigated by means of metallographic microscope, microhardness tester and universal testing machine. The results indicate that with the welding power of 41 kW, welding time of 1.1 s, and pressure time of 0.2 s, excellent performance of aluminum-steel butt welding joint can be achieved, and the maximum tensile strength can reach 149 MPa, which is about 77% of that of 6061 aluminum alloy resistance butt welding joints. Moreover, mechanical properties are improved after adopting cone end face and adding argon gas protection with zinc as intermediate transition layer, and the tensile strength reaches 172 MPa with the cone end face diameter of 7 mm, which is about 89% of that of 6061 aluminum alloy resistance butt welding joints. Zn transition layer leads to the enhancement of tensile strength and hardness of welded joints, while Cu transition layer is unable to effectively inhibit the formation of Al-Fe intermetallic compounds at the interface, resulting in a reduction in tensile strength of welded joints.更多还原