Experimental Study on Dynamic Modulation Op-timization of Micro-Hole Morphology in Wa-ter-Assisted Laser Drilling

IN718 alloy, a typical nickel-based superalloy, is widely used in key components such as turbine blades and combustion chambers in aircraft engines due to its excellent high-temperature strength, creep resistance, and corrosion resistance. However, the material's high-temperature strength, poor thermal conductivity, and low plasticity lead to low efficiency in traditional machining and severe tool wear. Laser processing, with its high energy density, non-contact nature, and flexibility, is considered an effective method for machining micro-holes in high-temperature alloys. However, laser micro-hole processing in air still faces problems such as large hole expansion, rough hole walls, a large heat-affected zone, and thick oxide layers. To address these issues, this paper introduces a water-assisted environment and combines pulse delay technology to explore its effects and mechanisms in the micro-hole processing of IN718 alloy.