Optimization of Dimensional Accuracy for the Nd:YAG Laser Cutting of Aluminium Alloy Thin Sheet Using a Hybrid Approach
P. Joshi and A. Sharma
Al-alloys are the most widely used sheet material in the world after steel because of their exceptional properties. Al-alloy sheets are used for producing structural parts of aircrafts and automobile components. This paper presents the optimization of dimensional accuracy of kerf geometry during pulsed Nd:YAG laser cutting of thin Al-alloy sheet. Top kerf width, bottom kerf width and top kerf deviation are considered as quality characteristics for laser cut kerf. These laser cut quality characteristics are the functions of four laser cutting parameters namely O2 gas pressure, pulse width, pulse frequency and cutting speed. Experimental results of these characteristics have been obtained by performing the experiments using L9 orthogonal array (OA) and these results are optimized simultaneously using Grey relational analysis (GRA) coupled with fuzzy logic (FL). Subsequently, the significance of laser cutting parameters for the process has been found by employing the analysis of variance (ANOVA). From the results, pulse frequency is found as the most contributing (48.40%) laser cutting parameter for the study.
Keywords: Nd:YAG laser, aluminium alloy, Al-alloy, sheet cutting, operating parameters, Grey relational analysis (GRA), fuzzy logic (FL), optimization