2219铝合金直流正极性A-TIG焊接技术

提出了一种用于2219铝合金焊接的新方法，焊前在待焊表面预先涂敷一层除气去膜活性剂，实现了2219铝合金的直流正极性焊接. 研究不同的活性剂浓度对2219铝合金直流正极性活性TIG焊(A-TIG)焊缝表面成形、气孔缺陷、微观组织以及力学性能的影响. 结果表明,当活性剂浓度为10%时可以获得无气孔缺陷、表面成形和力学性能良好的2219铝合金直流A-TIG焊缝. 与变极性TIG焊相比，焊接过程电弧稳定性好，热输入小，焊缝质量优异.

Direct current straight polarity A-TIG welding technology of 2219 aluminum alloy

A new welding method was proposed innovatively for joining 2219 aluminum alloy. The welding surface was coated with a thin layer of activating flux with a function of removing the oxide film and gas before welding. And direct current straight polarity TIG welding method of 2219 aluminum alloy was obtained. This paper investigated the effect of activating flux concentration on the weld surface appearance, porosity defect, microstructure and mechanical properties of 2219 aluminum alloy joints by direct current straight polarity A-TIG welding. The results showed that the 2219 aluminum joint with pore-free, sound surface appearance and excellent mechanical properties was obtained when the activating flux concentration was up to 10%. Compared with the variable polarity TIG welding, direct current straight polarity A-TIG welding presented better arc stability, less heat input, more excellent welding quality.