IJSRD - International Journal for Scientific Research & Development| Vol. 1, Issue 5, 2013 | ISSN (online): 2321-0613 All rights reserved by www.ijsrd.com 1116 Abstract--In today’s world, composite materials have many engineering application for manufacturing, packaging, automobile industry. For the machining of these composite materials, many accurate and cost effective machining processes have been used to reduce the machining time and man hour. The work piece of composite material of aluminium 6061 and silicon carbide powder of 100 mesh is prepared by the stir casting process with different weight fraction of powder in aluminium matrix. The prepared work piece of the composites are then carried out for machining on Ultra Sonic Machine to evaluate the tool wear rate with different process variables which are work piece material composition, amplitude, pressure and thickness of composite sheet. Experiments have been conducted to conclude that by changing the amplitude, tool wear is effectively increased at higher rate. Other variables also make definite changes which are smaller in comparison to amplitude. The comparison of mathematical model with experimental results will also serve as future validation of the model. Keywords: Tool wear, Ultrasonic machining, SiC., Taguchi I. INTRODUCTION With the development of technology, more and more challenging problems are faced by the engineers and technologists in the field of manufacturing. Recently, many new engineering materials have been developed, many of which are very difficult to machine. This applies particularly to super-hard materials, such as tungsten and titanium carbides, diamonds, hard steels, magnetic alloys and corundum. Grinding is the only technique used for machining these materials. Another group of materials, like germanium, silicon, ferrite, ceramics, glass, and quartz gives difficulty in machining on account of their higher brittleness. These materials often not able to withstand the forces needed for shaping .The complex shapes in these materials are either difficult to machine or time-consuming by the traditional processes. The need for methods of shaping these unshakable materials with the requirements of higher production rate at cheaper rates may demand the use of non-traditional processes. In USM, high frequency electrical energy is converted into mechanical vibrations via a transducer/booster combination which are then transmitted to an energy focusing as well as amplifying device: horn/tool assembly (fig.1). This causes the tool to vibrate along its longitudinal axis at high frequency [5]; usually above 20 kHz with amplitude of 12-50 μm. The power ratings range from 50- 3000 W and a controlled static load is applied to the tool. Abrasive slurry, which is a mixture of abrasive material; e.g. silicon carbide, boron carbide or aluminum oxide suspended in water or some suitable carrier medium is continuously pumped across the gap between the tool and work (~25-60 μm). The vibration of the tool causes the abrasive particles held in the slurry to impact the work surface leading to material removal by micro chipping [6]. Aluminium and its alloys are alternative for many engineering applications due to their superior properties such as chemical inertness, high strength and stiffness at elevated temperatures, high strength to weight ratio, corrosion resistance, and oxidation resistance. However these properties also make Aluminium and its alloys difficult to shape and machine into a precise size and shape. As a result, their widespread applications have been hindered by the high cost of machining with current technology [1]-[3]. The machining characteristics for Aluminium and its alloys using conventional machining processes are summarized below [3]-[4]: 1) Aluminium and its alloys are poor thermal conductors. As a result, the heat generated when machining Aluminium cannot dissipate quickly; rather, most of the heat is concentrated on the cutting edge and tool face. About 50% of the heat generated is absorbed by into the tool while machining Aluminium alloy (6061Al). 2) During machining, Aluminium alloys exhibit thermal plastic instability that leads to unique characteristics of chip formation. The shear strains in the chip are not uniform; rather, they are localized in a narrow band that forms serrated chips. 3) -The contact length between the chip and the tool is extremely short (less than one-third the contact length of steel with the same feed rate and depth of cut). This implies that the high cutting temperature and the high stress are simultaneously concentrated near the cutting edge (within 0.5 mm). 4) -Serrated chips create fluctuations in the cutting force; this situation is further promoted when alpha-beta alloys are machined. The vibrational force, together with the high temperature, exerts a micro-fatigue loading on the cutting tool, which is believed to be partially responsible for severe flank wear. Therefore, there is a crucial need for reliable and cost effective machining processes for Aluminium and its alloys. Over the last few decades, there have been great advancements in the development of cutting tools, including coated carbides, ceramics, and cubic boron nitride and polycrystalline diamond. These have found applications in the machining of cast iron, steels and high temperature alloys such as nickel based alloys and super alloys. However, none of these newer developments in cutting tool materials have had successful Tool Wear Analysis of USM for Composite Material using Taguchi Technique Bhupesh Goyal 1 Alpesh Makwana 2 Akash Pandey 3 1 M.Tech 2, 3 Assistant Professor 1,2 Mechanical Department, Government Engineering College, Dahod 3 Faculty of Tech. & Eng., Maharaja Sayajirao University, Vadodara