Optimization of Machining Parameters for Surface Roughness in the End Milling of Hybrid Composite Using Response Surface Methodology

A certain degree of machining must be done on hybrid composites (glass and carbon fibres), created by basic manufacturing procedures, so as to achieve close fits and tolerances. End milling is a common method for finishing machined flat plate hybrid composite products, having aerospace, automobile, wind turbine blade and prosthetic applications. This study was performed using, PVD TiAlN coated carbide tools, under dry conditions. Three input parameters, namely nose radius, having two levels, cutting speed and feed rate, having three levels each were considered. Surface roughness parameter Ra was considered as the output performance measure. Taguchi L18 orthogonal array (OA) was applied for the design of experiments. Response surface methodology was adopted to optimize the input performance parameters. A response surface was generated to investigate the effect of input variables and their interactions on the response. From the analysis of the mean effect plot, it was observed that the most significant input parameter on surface roughness was the feed rate. Optimization results revealed that the best surface roughness was observed at a combination of A1B2C1, i.e. nose radius of 1 mm, cutting speed of 94.69 m/min and feed rate of 300 mm/min.