背面成形对A7NO1铝合金激光-MIG复合焊接头组织性能的影响

Influence of back forming methods on microstructure properties of welded joint in Laser-MIG hybrid welding for A7N01 aluminum alloy

针对高速列车用6 mm厚A7N01P-T4铝合金,进行强制成形和背部加永久垫板两种接头形式的激光-MIG复合焊接试验,并对比分析焊接接头的宏观成形、显微组织、力学性能,以此研究激光-MIG复合焊对两种接头型式的适应性。实验结果表明,两种接头型式均可获得外观成形良好、显微组织正常的焊缝;而力学性能方面,当背部加永久垫板时的接头抗拉强度较强制成型时的接头提高11 MPa,激光-MIG复合焊接高速列车用6 mm厚A7N01P-T4铝合金板时采用背部加永久垫板的接头形能取得较好的性能。

Laser-MIG hybrid welding is applied to weld 6 mm thickness A7N01P-T4 aluminum alloy profile of high speed train. The joint type with permanent backing plate and copper backing plate are used in this study. Weld formation, microstructure and mechanical properties of welded joint are studied to research the condition suitability for joint type of laser-MIG hybrid welding. The results show that different joint types can get similar weld formation and microstructure, but the tensile strength of the joint with permanent backing plate is improved, and 11 MPa more than the other. Joint with permanent backing plate is more suitable for laserMIG hybrid welding of 6mm thickness A7N01P-T4 aluminum alloy profile.