Investigations on Machinability Behavior in Turning of Al7075/Beryl/Graphene Nano Platelets Hybrid Composites with Multilayer Coated Carbide Insert Using Taguchi and Statistical Techniques

Abstract

This work emphases on characterization and evaluation of machinabity characteristics of a novel hybrid Aluminum Metal Matrix Composite (AMMC) developed through two-step stir-casting method by reinforcing constant amount of Beryl (6%) and varying quantity of Graphene nanoPlatelets - GNPs (0%, 1% and 2%). Morphological analysis result shows the presence of dendritic arms and homogeneous distribution of the Beryl and GNPs in Al7075 matrix. Machinability (turning) characteristics of the developed hybrid composite were studied in detail besides optimizing the machining parameters employing Taguchi technique. The objective was to establish a correlation between cutting parameters such as cutting speed, feed rate and depth of cut with, tool wear, and surface roughness on work piece. In the present study, performance of multilayer hard coatings (TiC/TiCN/Al2O3) on cemented carbide insert for machining of Al7075-Beryl-GNPs. An attempt has been made to analyze the effects of process parameters on machinability aspects using Taguchi technique. Response surface plots are generated for the study of interaction effects of cutting conditions on machinability factors. The correlations were established by multiple linear regression models. The linear regression models were validated using confirmation test.