Abstract:Recently, laser cutting technologies begin to use for manufacturing mechanical parts of Inconel super-alloy sheet due to difficulties of machining of the Inconel material as a results of its extremely tough nature. The objective of this work is to investigate the influence of cutting parameters on surface characteristics of the cut section in the cutting of Inconel 718 super-alloy sheet using CW Nd:YAG laser through laser cutting experiments. Normal cutting experiments were performed using a laser cutting system with six-axis controlled automatic robot and auto-tracking system of the focal distance. From the results of the experiments, the effects of the cutting parameters on the surface roughness, the striation formation and the microstructure of the cut section were examined. In addition, an optimal cutting condition, at which the surface roughness is minimized and both the delayed cutting phenomenon and the micro-cracking are not initiated, is estimated to improve both the part quality and the cutting efficiency.

Key words: Inconel 718 sheet; CW Nd:YAG laser; cutting parameters; surface roughness; cut and break ratio; surface qualities; optimal cutting condition