Experimental research on femtosecond laser helically machining micro-holes

Abstract Micro-holes are widely used in many industrial fields, and their processing quality often affects the performance of the entire product. However, the machining of micro-holes would face the challenges of short tool life, low machining efficiency, low machining accuracy, and poor surface quality. Femtosecond laser has the characteristics of ultra-short pulse duration and ultra-high instantaneous power, which can realize non-contact, high-precision and high-quality processing of materials. In this paper, the micro-hole processing experiment on stainless steel was carried out by femtosecond laser. The influence of laser power, defocusing distance, and scanning depth on the diameter and conicity of the micro-hole was studied.