Optimization of CNC Turning Process Parameters for Surface Roughness and Material Removal Rate Using the Taguchi Method

Abstract

Computer numerical control turning is among the most widely used machining processes, and the selection of cutting parameters strongly influences both the quality of the machined surface and the productivity of the operation. Surface roughness and material removal rate are, however, conflicting objectives, so that a systematic approach to parameter selection is required. This paper applies the Taguchi method to optimise the turning of a medium-carbon steel, considering cutting speed, feed rate, and depth of cut as the control factors. A standard L9 orthogonal array was used to plan the experiments, surface roughness was measured with a stylus profilometer, and material removal rate was computed from the cutting conditions. Signal-to-noise ratios and analysis of variance were employed to identify the most influential factors and the optimal parameter combination for each response. The results show that feed rate is the dominant factor governing surface roughness, whereas depth of cut and cutting speed contribute most to material removal rate. The study confirms that the Taguchi approach offers an efficient route to balanced parameter selection, and the identified settings provide practical guidance for finishing and roughing operations. KEYWORDS: CNC Turning, Taguchi Method, Surface Roughness, MaterialRemoval Rate, Orthogonal Array, Process Optimization, Signal-to-NoiseRatio