Evaluation of hard coating materials performance on machinability issues and material removal rate during turning operations

The potential of various varieties of hard outer surface coats of carbide inserts on surface roughness, material removal rate (MRR) and flank wear, are scrutinized based on an experimental study using standard orthogonal array L-16(4<^>3 x 2<^>1). For this motive, AISI 304 austenitic stainless steel is turned applying five divergent varieties of coated carbide inserts over a gamut of cutting parameters that include cutting speed, feed depth of cut and nose radius. Among the selected coated carbide inserts, turning by physical vapour deposition (PVD) coated with TiAlN-TiN layers cemented carbide insert obtained the lowest average surface roughness value (1.06 mu m) and the lowest average flank wear value (0.1580 mm). The maximum average MRR (29248.9 mm(3)/min) is obtained by chemical vapour deposition (CVD) [ Ti (C, N) + Al2O3] layer cemented carbide coated tool. It is found out that the fundamental theoretical tendency of surface roughness values in respect of feed rate is different from the experimental values. Further, the most significant factors affecting the machinability issues and MRR are identified using analysis of variance (ANOVA). Reasonably accurate mathematical models are developed for prediction of machinability issues and MRR within limits. (C) 2018 Elsevier Ltd. All rights reserved.