Nd:YAG激光与半导体激光复合焊接对铝合金焊缝组织和性能的影响

目的 提高铝合金的焊缝抗拉强度，解决铝合金焊接过程中的裂纹缺陷。方法 采用脉冲Nd:YAG激光与半导体激光复合焊接铝合金，先用Nd:YAG激光形成焊接熔池，然后用半导体激光对熔池进行加热保温，获得无裂纹的焊缝，并对焊缝进行抗拉强度测试。结果 与单独的Nd:YAG激光焊接相比，Nd:YAG激光与半导体激光复合焊接的铝合金焊缝抗拉强度提高了50%，达到193 MPa，为母材抗拉强度的90%。结论 2束激光的结合延长了熔池的冷却凝固时间，从而有效避免了热裂纹，减少了焊接缺陷，提高了焊接质量。

Effects of Nd:YAG Laser and Diode Laser Hybrid Welding on Microstructure and Properties of Aluminium Alloy Laser Weld

The work aims to improve the tensile strength of aluminum alloy weld and solve the crack defect during welding of aluminum alloy. Pulsed Nd:YAG laser and diode laser hybrid welding was adopted to weld the aluminum alloy. First, the Nd:YAG laser was used to form a welding pool. Then, the pool was heated and kept warm by diode laser to obtain crack-free welds and test the tensile strength of the welds. The tensile strength of aluminium alloy weld left by pulsed Nd:YAG laser and diode laser hybrid welding was 50% higher than that of the single Nd:YAG laser welding, reached to 193 MPa, which was 90% of the tensile strength of the base metal.The combination of laser beam prolongs the cooling and solidification time of the molten pool, thus avoids the hot crack effectively, reduces the number of welding defects and improves the welding quality.