Fig. 1. Schematics of small-core-diameter laser oscillation welding platform. (a) Welding platform; (b) galvanometer system

Fig. 2. Schematics of motion trajectory

Fig. 3. Schematics of beam motion trajectories under different oscillation frequencies

Fig. 4. Effect of spot radius on energy distribution. (a) 0.014 mm; (b) 0.028 mm; (c) 0.056 mm; (d) 0.102 mm

Fig. 5. Effect of welding speed on energy distribution. (a) 15 mm·s^-1, (b) 20 mm·s^-1, (c) 25 mm·s^-1, (d) 30 mm·s^-1

Fig. 6. Effect of oscillation frequency on energy distribution. (a) 100 Hz; (b) 150 Hz; (c) 200 Hz; (d) 300 Hz

Fig. 7. High-speed camera images of welding processes under different oscillation frequencies. (a) 50 Hz; (b) 100 Hz; (c) 150 Hz; (d) 200 Hz

Fig. 8. Schematics of welding formation and depth-to-width ratios under different parameters. (a) Welding speed of 15 mm·s^-1 and oscillation frequency of 50 Hz; (b) welding speed of 20 mm·s^-1 and oscillation frequency of 50 Hz ; (c) welding speed of 25 mm·s^-1 and oscillation frequency of 50 Hz ; (d) welding speed of 30 mm·s^-1 and oscillation frequency of 50 Hz ; (e) welding speed of 20 mm·s^-1 and oscillation frequency of 100 Hz; (f) welding speed of 20 mm·s^-1 and oscillation frequency of 150 Hz; (g) welding speed of 20 mm·s^-1 and oscillation frequency of 200 Hz; (h) welding speed of 20 mm·s^-1 and oscillation frequency of 250 Hz; (i) depth-to-width ratio

Table 1. Chemical compositions of 2A12 aluminum alloy

Table 2. Welding parameters of 2A12 aluminum alloy with laser oscillation