Study on micro-hole morphology of Ni-based superalloy optimized by pulse-delay dynamic modulation of nanosecond laser

Ni-based superalloys are widely used in aerospace for their excellent high-temperature properties.. To address thermal damage and dimensional ac-curacy issues faced by IN718 in high-power nanosecond laser micro-drilling, this study proposes a pulse-time modulation strategy. By dynamically con-trol-ling heat accumulation through precise pulse-delay adjustments, a seg-mented energy delivery mechanism enhances through-hole quality. Two pulse-delay op-timization strategies are proposed and verified in comparison with the conven-tional processing: the optimized hole size accuracy is improved by 70%, the av-erage roughness of the hole wall is reduced by 30%, and the ta-per of the through-hole is reduced by 54%.