Experimental Investigation on Femtosecond Laser Ablation of Stainless Steel

Experiment on femtosecond laser ablation of stainless steel(SUS420) was carried out. The stainless steel was irradiated by femtosecond laser with a wavelength of 780 nm,a pulse width of 164 fs,and repetition rate of 1k Hz under the static experimental condition. The ablation process and result were compared with ultrashort laser and long pulsed laser ablation of stainless steel. The ablation threshold of femtosecond laser ablation of stainless steel was calculated and incubation coefficient of multi femtosecond laser pulse ablation of stainless steel was obtained. The results shows that femtosecond laser ablation of stainless steel has small heat affected zone;ablation threshold of single femtosecond laser pulse ablation of stainless steel is 0.25J/cm2 and incubation coefficient is 0.68;the diameter and depth of the ablated hole can be adjusted by changing the pulse energy and number of the laser pulse.