Fig. 1. Experimental equipment. (a) TruDisk-12003 disk laser; (b) KUKA KR30HA welding robot

Fig. 2. Schematic of laser welding

Fig. 3. Microstructure of laser welded Al-Li alloy joint. (a) Cross-sectional morphology of joint; (b) microstructure of base metal; (c) microstructure at weld seam boundary; (d) columnar crystal; (e) equiaxed crystal; (f) local microstructure of weld seam

Fig. 4. Characteristics of molten pool flow in process of laser deep penetration welding of aluminum alloy sheet

Fig. 5. Microstructure of joint. (a) Cross-sectional morphology; (b)-(d) microstructures at different boundary positions of weld seam