交流频率及装配质量对单面自动焊接头性能的影响分析

开展了6 mm 2A14-T6铝合金对接接头的单面焊双面成形焊接工艺研究,详细分析了交流频率和装配精度对焊缝成形及接头力学性能的影响规律。结果表明:随着交流频率从60 Hz逐渐增加至80 Hz,2A14铝合金对接接头的平均抗拉强度从356 MPa降低至310 MPa,但接头延伸率没有显著变化。装配精度对焊缝质量的影响分析结果显示:随着装配间隙增大,焊缝背部成形效果变差。当间隙超过20%板厚时,焊缝易直接熔穿或单面切割,无法形成焊漏。随着装配错边增大,焊缝背部成形逐渐变差,出现咬边现象;接头力学性能测试显示,随着装配错边的增加,接头抗拉强度和延伸率均呈逐渐下降的趋势。在实际工程应用中,局部错边应控制在25%板厚范围内。

Effect of Alternating Current Frequency and Assembly Quality on Properties of One-Side Automatic Welding Joint

This paper investigated the welding process of one-side welding with backing formation of 6 mm 2A14 -T6 aluminum alloy, and analyzed the discipline of the alternating current frequency and assembly accuracy to the welding formation and the joint performance. The results showed that with the AC frequency gradually increased from 60 Hz to 80 Hz, the average tensile strength decreased from 356 MPa to 310 MPa, but the joint elongation did not change significantly. The analysis of assembly accuracy showed that the body material would be burnt through or single cutting by one-side when the assembly clearance exceeded 20% of thickness which was unable to form welding leakage. On the other way, when the larger assembly stagger was come out, the mechanical properties of joint decreased obviously. In addition, the influence of stagger on the performance was greater than the clearance. When the stagger was increased, the backing formation would be worse. The result of joint performance showed that if the stagger was greater, the joint tensile strength and elongation declined gradually. So in practical engineering applications, the local stagger of joints should be controlled within 25% of thickness.