681910.fig.001a
(a)
681910.fig.001b
(b)
Figure 1: (a) Macrostructures of weld at different welding conditions for 6061T6-5052H32 sheet combination (dissimilar Al grades): (A) rotational speed: 1500 rpm; plunge depth = 1.95 mm; shoulder diameter = 16 mm; welding speed = 80 mm/min; (B) rotational speed: 1500 rpm; plunge depth = 1.95 mm; shoulder diameter = 16 mm; welding speed = 130 mm/min; (C) rotational speed: 1500 rpm; plunge depth = 1.95 mm; shoulder diameter = 12 mm; welding speed = 80 mm/min; RS: 5052H32, AS: 6061T6. (b) Macrostructures of weld at different welding conditions for 6061T6-6061T6 sheet combination (similar Al grades): (A) rotational speed: 1100 rpm; welding speed: 90 mm/min; shoulder diameter: 18 mm; plunge depth = 1.8 mm (defective case); (B) rotational speed: 1300 rpm; welding speed: 90 mm/min; shoulder diameter: 12 mm; plunge depth: 1.9 mm; (C) rotational speed: 1350 rpm; plunge depth: 1.9 mm; shoulder diameter: 18 mm; welding speed = 120 mm/min [17].