AA6063-T6铝合金激光焊接实验研究

采用3500 W Slab CO2激光器，对厚度为5 mm的AA6063-T6铝合金板材进行了激光填丝对接焊接实验研究。测定了AA6063铝合金激光焊接的功率阈值，探讨了激光填丝焊接工艺参数对焊缝成型的影响，并对不同填充焊丝焊接接头的强度及拉伸断口形貌进行了分析。研究结果表明，在合适的工艺参数下，可以获得表面光洁、正反面焊缝成型良好的对接接头;焊态下，单面焊接不填充焊丝的接头强度为180.7 MPa;单面焊接填充AlSi12,AlMg4.5MnZr焊丝的接头强度最低为190 MPa，且两种填充焊丝接头的拉伸强度无明显差异;双面焊接填充AlMg4.5MnZr焊丝的接头强度达到200.7 MPa，约为母材的90%。对于单面焊接接头，由于填充材料难以进入焊缝内部及根部存在气孔加剧了拉伸强度较低的程度。

Experimental Study on CO2 Laser Beam Welding of AA6063-T6 Aluminum Alloy

Bead-on-plate and butt welding of AA6063-T6 aluminum alloy plates with a thickness of 5 mm is carried out by applying a 3500 W Slab CO2 laser. The penetration welding threshold is measured, and the influences of welding parameters on the process stability are studied. Meanwhile, the different joint tensile strength and appearances are tested. The results demonstrate that welds with good appearances could be obtained when welding with the appropriate processing parameters. The as-welded joint tensile strength without filler wire is 180.7 MPa, while the tensile strength is 190 MPa when welding by one side with the filler wire of AlSi12 or AlMg4.5MnZr. However, the joint tensile strength increases up to 200.7 MPa when welding by both sides with the filler wire of AlMg4.5MnZr, which is about 90% of the base-metal tensile strength. The main reasons for the lower tensile strength when welding by one side are that the filler metal can not totally enter the bottom of the weld and there are porosities at the root of weld.