TOPSIS BASED EVALUATION OF LASER CUTTING RESULTS IN CO2 LASER CUTTING OF 3 MM THICK ALUMINIUM ALLOY

Abstract

Laser cutting is complex machining process which involves a number of parameters and process performance characteristics. In literature and practice a number of criteria for evaluation of laser cutting results were proposed. In this study, for the purpose of evaluation of laser cutting results obtained in CO₂ laser cutting of 3 mm thick aluminium alloy, a set of criteria proposed by TRUMPF was considered. In order to deal with a number of criteria as well as performance characteristics, both quantitative and qualitative, a multi criteria decision making (MCDM) method was applied, i.e. the technique for order of preference by similarity to ideal solution (TOPSIS). Laser cutting experiment was conducted according to the full factorial experimental design by varying laser power, cutting speed and assist gas pressure at three levels. Based on experimental data the MCDM model with 27 alternatives (laser cuts) and six criteria was developed. The relative importance of criteria was determined by using pair-wise comparison matrix and geometric mean method of the analytic hierarchy process (AHP) method.