IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 __________________________________________________________________________________________ Volume: 02 Issue: 11 | Nov-2013, Available @ http://www.ijret.org 381 PERFORMANCE EVALUATION OF NANO GRAPHITE INCLUSIONS IN CUTTING FLUIDS WITH MQL TECHNIQUE IN TURNING OF AISI 1040 STEEL M M S Prasad 1 , R.R.Srikant 2 1 Professor, Dept of Mechanical Engg, Regency Institute of Technology, Yanam-U T of Puducherry, India 2 Associate Prof, Dept of Mechanical Engg, GIT, GITAM University, Visakhapatnam, A.P., India prasadmms@yahoo.co.in, r.r.srikant@gmail.com Abstract Liberation of heat and generation of friction associated with any machining operation ever pose a problem which not only reduce the tool life but also impair quality of the product. Cutting fluids have been the conventional choice to curtail friction and temperatures in machining because of its lubrication and cooling actions. However, considering health hazards posed by the conventional cutting fluids to health of the workers and ecology, the quest is towards identifying alternative strategies to the usual flood application. Selection and use of proper lubricant that can improve the overall cutting phenomena which is an important aspect in reducing the cutting forces and temperatures The present work studies the use of nano cutting fluids in MQL which is a minimal cutting fluid technique, for turning operation using HSS and cemented carbide tools. Development of nano materials by nanotechnology technique, dispersing them in the cutting fluid improve the effectiveness of the cutting fluid and hence nano graphite powder is selected of particle size 80 nm in varying proportions i.e. 0.0%, 0.1%, 0.3% and 0.5% by weight are mixed in water soluble oil and applied drop by drop. Experimentation is carried out at different flow rates like 5 ml/min 10 ml/min and 15 ml/min with nanoparticle suspended fluids along with dry machining, flood coolant machining under constant cutting conditions. Experimental results are very encouraging with much reduction in surface roughness, tool flank wear, temperatures and cutting forces is observed in fluids with nanoparticle inclusions. Different properties of the nanofluids are estimated through a series of standard tests. Keywords: Machining, nano Graphite, minimum quantity lubrication, cutting fluids. ----------------------------------------------------------------------***----------------------------------------------------------------------- 1. INTRODUCTION Machining is one of the major manufacturing processes and is often accomplished by very high energy consumed to shear off the material by the cutting tool. Due to this, abnormal amount of friction and in turn very high temperatures are generated at the tool, work and chip interfaces. Inadvertently, the machining parameters like cutting force, tool wear and surface roughness are to be increased [1]. In order to reduce the these parameters, cutting fluids are the best choice as they provide cooling and lubrication to the cutting zone [2,3]. However, cutting fluids introduce major health and safety concerns, high handling and carrying costs, disposal, water and soil pollution,[4,5] exposure to cutting fluids for long term causes dermatitis [6] . It was estimated by the National Institute for Occupational Safety and Health (NIOSH) that in every year 1.2 million workers involved in machining, forming and other metal working operations are exposed to metal working fluids [7]. It was reported recycling services for the cutting fluids in the United States charge twice the purchasing price for disposal and the cost is four times as much in Europe [8]. This has prompted the search for alternative methods, wherein the use of cutting fluids is minimized. Minimum Quantity Lubrication (MQL) is one such strategy where very minimal amounts of the fluids are used. Nevertheless, to achieve high cooling ability with minimum quantity lubrication, a fluid with high thermal conductivity of the fluids, like nanofluids, must be chosen [9-11]. 2. LITERATURE REVIEW Cutting fluids are said to be accounting to major expenditure in any metal cutting industry, in fact more than the cost of the cutting tools [12]. Considering the stringent environmental laws, high cost of the cutting fluids, ecological and issues related to health hazards, various methods are evolved to minimize or eliminate the usage of the cutting fluids [13]. This has lead to the development of minimum quantity lubrication (MQL) [14]. MQL has been applied in several operations like turning, milling and grinding and encouraging results were obtained [14-16]. However, since the amount of fluid supplied is very low, a fluid with superior properties, compared to the