Taguchi-Grey Relational Based Multi-Response Optimization on the Performance of Tool Coating Thickness in Pocket Milling

In this paper, the Taguchi method and Grey relational analysis is used to evaluate the effect of tool coating thickness by machining Titanium Alloy Grade 5 (Ti6Al4V) with Titanium Aluminium Nitrate (TiAlN) Nano coated tools by varying their coating thickness. The pocket milling operation is carried out using the L9 orthogonal array with three levels and four factors design on the CNC vertical machining center. The tool coating thickness, spindle speed, feed rate and depth of cut was selected as machining input parameters for the experiment. The various output parameters such as cycle time, tool wear, surface roughness, material removal rate, micro hardness were found out after machining process. After obtaining all the output parameters the optimization was done by finding out the S/N ratio and grey relation analysis method. According to grey relational grading it was found out that tool coating thickness is the most affected factor for the machining. The confirmation test was done using the optimized value and the results obtained were close to each other. (C) 2017 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of International Conference on Materials Manufacturing and Modelling (ICMMM - 2017).