an experimental investigation of the effects of fiber laser percussion drilling: influence of process parameters

this study is focused on investigating the parameters of laser percussion drilling process of nickel-base super alloy inconel 718 with thickness of 1 mm. fiber laser with the power of 500 watts was used as the laser source. laser pulse frequency, duty cycle, laser power, focal point position, were assumed as the laser drilling process variables. the hole geometry features, i.e. entrance hole diameter, circularity of entrance hole, and hole taper were measured. the results indicated that pulse frequency of laser has a direct influence on the entrance hole diameter. increasing the duty cycle leads to increases in hole taper. by increasing the laser power, entrance diameter and hole taper increases.