Fig. 1. Surface roughness test results of superalloy samples

Fig. 2. Schematic diagram of ultrashort pulse laser processing system

Fig. 3. Morphologies of ablation holes irradiated by 100 laser pulses with a pulse width 290 fs at different pulse energy

Fig. 4. Curves of ablation hole diameter vs laser energy for the superalloy surface after the irradiation of ultrafast laser with different pulse duration

Fig. 5. Curves of square of ablation hole diameter vs laser energy for the superalloy surface irradiated by ultrafast laser with different pulse duration

Fig. 6. Curves of the ablation threshold vs number of pulses