Experimental Investigation of the Dimensional Accuracy and Circularity when Nd:YAG Laser Microdrilling Cu Sheet
S. Vidya, A. Wazeer, M.N. Equbal, P. Mathiyalagan and K. Rajput
Laser machining has become a prominent tool for macro as well as micro-manufacturing because of their increasing demand in industries such as electronics, aerospace, turbine, automobile, etc. Among various laser-based machining processes, laser drilling has gained importance due to requirements of precise and high aspect ratio holes. Apart from machining capabilities, the quality of microholes in terms of shape, size and tolerance matters to a great extent. So in this paper we investigate the dimensional accuracy and quality in terms of the circularity of microholes of 100 μm diameter drilled in Cu sheet using a Nd:YAG laser. The microholes were analysed to evaluate the geometrical profile and the measured data were examined to obtain their quality characteristics. The standard deviation was 2.98 μm having a mean error of 21.75 μm. Ferret’s diameter analysis revealed that the average circularity of the microholes was 0.95. A recast layer was observed which was generated due to resolidification of melt onto the walls of holes.
Keywords: Nd:YAG laser, copper, Cu sheet, laser microdrilling, microholes, geometric profile, circularity