EXPERIMENTAL ANALYSIS OF THE INFLUENCE OF LUBRICATION STRATEGY AND MACHINING PARAMETERS ON SURFACE ROUGHNESS & TOOL WEAR INMILLING OF TI- 6AL-4V USING TAGUCHI BASED GREY RELATIONAL ANALYSIS

Suddenly increased demand of titanium in Aerospace and medical industry is attracting the focus towards titanium machining now a days. Titanium in spite of several good properties like high strength to weight ratio and excellent corrosion resistance, it is one of the difficult to cut material because of its low thermal conductivity and high reactiveness at elevated temperature. Ninety percent of the aerospace parts require milling operation hence this paper focuses on milling operation. Titanium milling is constrained by low speed, feed and depth of cut during machining, low MRR, high temperature, costly tooling, and shorter tool life and requires high pressure coolant to be sprayed to cutting zone. All above constraints makes titanium difficult to cut and contribute towards increased environmental burden. Therefore it is necessary to find sustainable machining methods for titanium which will reduce coolant consumption and increase tool life without sacrificing the surface quality. This paper therefore focuses on experimental analysis using Taguchi based GRA to find influence of various factors on tool wear and surface roughness. Method of grey relational analysis is used for multi objective optimization. Taguchi L16 orthogonal array is used and flood cooling and MQL strategy is compared. The optimum combination consists of MQL at 200ml/hr flow rate, Speed 1000 rpm, Feed 0.06 mm/tooth and depth of cut of 0.6mm. At this combination the values of tool wear and surface roughness are 0.068mm and 0.271 micro meter respectively. The TiALN coated carbide milling inserts used for experimentation Cooling strategy is also taken as one of the factors for Study.