EVALUATION OF MACHINABILITY BASED ON CUTTING FORCE AND SURFACE QUALITY CHARACTERISTICS USING THE TOPSIS METHOD

Abstract

The study proposes a multi-criteria machinability evaluation based on cutting forces, surface quality, and productivity characteristics obtained from CNC milling experiments. Three tool steels (1.2379, 1.2842, and ES Aktuell 1200) and four long-reach milling cutters were tested under controlled machining conditions. The experimental data set, including force components and surface roughness parameters, was analysed using the TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) method to integrate multiple performance indicators into a single metric, referred to as the Cutting Ability Index (CAI). The results show that the proposed approach enables the ranking of material-tool combinations and provides a more comprehensive interpretation of machinability compared to single-parameter evaluations. However, the resulting rankings are sensitive to the selection and balance of input criteria and, in certain cases, deviate from expected physical behaviour. This highlights the limitations of equally weighted multi-criteria approaches and underscores the importance of appropriate parameter selection and weighting. The study confirms that while TOPSIS can serve as an effective decision-support tool in machining analysis, its application requires careful methodological consideration.