International Journal of Innovative Technology and Exploring Engineering (IJITEE) ISSN: 2278-3075, Volume-9 Issue-2, December 2019 4120 Published By: Blue Eyes Intelligence Engineering & Sciences Publication Retrieval Number: B7436129219/2019©BEIESP DOI: 10.35940/ijitee.B7436.129219 Abstract: The sustainable cutting process emphasizes green manufacturing techniques, energy-efficient processes with improved quality characteristics. Titanium alloys pose difficulties and challenges during machining as increased speed alleviates temperatures and heat. To minimize the temperatures generated during titanium alloy machining mist-spray of lubrication in form of an aerosol minor quantity at low temperature is employed. In this work, a study of optimal machining controllable parameter data set required for turning of Ti6Al4V alloy under reduced quantity cooling lubrication (RQCL) was investigated. Experiments were designed using Taguchi designs and performed to optimize outputs vibration, surface quality, tool wear rate and Material removal rate (MRR) which are a function of input variables speed, feed and depth of cut(doc) on CNC lathe with PVD coated (TiAlN) carbide inserts. Taguchi design of experiments L16 orthogonal array is used and Date Envelopment Analysis based Ranking (DEAR) is used as multi-response performance enhancement. Speed is the most accentuate factor as far as tool wear rate is concerned which explains 80% of the variation. The tool life was drastically decreased at speed above 160mm/min. Multi performance rank index(MPRI) was calculated and optimum settings identified as speed 160mm/min, feed 0.2mm/rev and doc 1mm and MRR was increased by 25% in this setting. Keywords : Titanium Ti6Al4V, vibrations, MQCL, RQCL, Optimization, Taguchi, DEAR , tool wear, surface roughness. I. INTRODUCTION Titanium alloys Grade 5 (Ti-6Al-4V) is a type of α-β grade that finds applications in aerospace, biomedical industry, automobile industrial applications, power generation applications and defense industry due to strength advantage, corrosion resistance. The main drivers towards sustainable machining are a near zero waste and employment of frugal process selection by careful use of resource and energy-efficient methods and finally environment safety. High-speed machining is the buzz of the industry as speed augments productivity. However, HSM for Ti6Al4V poses many challenges owing to low thermal conductivity. This property aids in high heat energy build at cutting shear-zone thereby increasing cutting temperatures. At high speed tool wear at faster rate which in turn affects surface integrity [1]. Use of flood environment while cutting as lubricating agents pose threat to nature i.e. soil, water, and human. Hence recycling of the used oils is necessitating pollution control Revised Manuscript Received on December 05, 2019. * Correspondence Author V V K Lakshmi* ,Mechanical Engg department, GITAM deemed to be university, Visakhapatnam, India. Email: lakshmi.vennela@gmail.com K V Subbaiah , Mechanical Engg department, Andhra university, Visakhapatnam, India. Email: drkvsau@yahoo.co.in K Arun Vikram, Mechanical Engg department, GITAM deemed to be university, Visakhapatnam, India. Email: arunvikram@gmail.com which incurs costs. Therefore other efficient cutting environments like minimum quantity lubrication (MQL), MQCL, MIST methods gained momentum. The cutting-speed was the most significant factor which effects tool to wear under MQL conditions [2]. Vegetable oil-based mist combined with cooled air (MQCL) was used at a constant depth of cut was studied and reported that tool wear decreased with MQCL application and also surface roughness due to cooling effect [3]. Wear and temperatures optimization using Taguchi in a cryogenic environment with Tungsten Carbide (WC) with a coated tool was performed. Identified speed effect more on tool wear [4-6]. Optimization of variables was attempted using a hybrid technique combining Grey-relational-analysis coupled with AHP .The response studied are Surface integrity, MRR and wear of tool in dry condition using uncoated carbide insert. The compromise for surface roughness to increase productivity and decrease energy was reported to be compensated in finish cut [7].Grey relational analysis was used to optimization inputs for better surface quality, low temperature and MRR for a low machinability material[8].Texture was developed on tungsten carbide tool using spark erosion method on SS316 steel. The outputs MRR, Ra and wear were optimized using grey entropy method [14].The Taguchi S/N ratio was adopted to study the variability in cutting process using Ti-Al-Si-N PVD coated of nickel alloy for minimization of power consumed[16]. The emphasis of this research is on optimization of vibration, surface integrity, tool wear, and productivity while machining a difficult to cut Ti6Al4V under the mist –RQCL environment. Though much research has been reported in machinibility of Ti6Al4V, the surface integrity and productivity parameters have been studied individually and under different cutting environments. Since the machining objectives are conflicting it is imperative to go for a multi-objective optimization study and not much emphasis is given on the study of vibration and its effect on surface integrity. In the current study, the focus is on the study of the effect of vibration on surface quality, material removal rate (MRR) and tool-wear. By the application of RQCL, the research also focuses on cleaner production objectives by minimizing the lubrication quantity by cooling with air in form of aerosols, without compromise on other machining objectives. To achieve this special mixing chamber has been designed indigenously. The Responses were optimized using Taguchi - data envelopment analysis based ranking (DEAR) multi-criteria-decision making(MCDM) technique. The study also aims at the goal of achieving cleaner production by reducing the quantity of lubrication uncompromising on performance and surface integrity. Optimization of Controllable Factors for Turning of Ti-6Al-4V Alloy Under RQCL Environment V V K Lakshmi, K Venkata Subbaiah, K Arun Vikram