Experimental and Statistical Optimisation of Nd-YAG Crystal laser cutting process of INCONEL-718 using grey relational analysis

Inconel-718 is one of widely utilized Ni-based super alloys for aerospace engines applications. This is due to the superior thermos-mechanical properties and high temperature oxidation resistance. Also the weldability and post welding cracking is excellent. This paper aims to achieve optimal parameters while cutting thin sheet of Inconel-718 employed pulsed Nd-YAG laser. The Taguchi method will be used to reduce the variation in the process. The overall objective of this work is to obtain trustable optimal cutting parameters by performing smaller number of experiments aiming to reduce the cost. Kerf width, perpendicularity and number of striations are the parameters under investigation. Grey relational analysis (GRA), is utilised to reach the optimal cutting process parameters. these parameters are cutting speed 350 mm/min, pulse height 80%, pulse duration 1 ms. and pulse frequency 50Hz . Experimental verifications show a good agreement between the predicted and actual cutting process quality measures at the optimal cutting parameters.