http://localhost:8081/jspui/handle/123456789/8 2025-07-22T11:24:59Z 2025-07-22T11:24:59Z Kumar, Sadeep http://localhost:8081/jspui/handle/123456789/17966 2025-07-09T12:42:54Z 2013-06-01T00:00:00Z

Title: PARAMETRIC OPTIMIZATION AND iNVESTIGATION OF ULTRASONIC TURNING PROCESS Authors: Kumar, Sadeep Abstract: Ultrasonic Turning (UST) is of particular interest for the cutting of non-conductive, hard and brittle work piece materials, which are otherwise very difficult to machine by conventional machining. This is a variant process of ultrasonic machining (USM) These include high strength, stainless and heat resistant steels and alloys, titanium, ceramics, composites, glass and other non-metallic materials. These materials may not be suitable for conventional methods of machining due to the chipping or fracturing of the surface layer, or even the whole component, which results in a poor quality of the workpiece. Unlike other non-conventional processes such as laser beam, and electrical discharge machining, etc., Ultrasonic Turning does not thermally damage the work piece or appear to introduce significant levels of residual stress, which is important for the survival of brittle materials in its working lif. The principles and the mechanism of material removal of ultrasonic turning process is same as for ultrasonic machining i.e. erosion. The fundamental principles of Ultrasonic Turning the effect of operating parameters on material removal rate. tool wear rate and surface roughness are reviewed and the parametric optimization olthe process is being done.

2013-06-01T00:00:00Z Singh, Rohit http://localhost:8081/jspui/handle/123456789/17965 2025-07-09T12:42:46Z 2013-06-01T00:00:00Z

Title: MACHINABILITY STUDIES ON ALUMINIUM BASED METAL MATRIX COMPOSITES Authors: Singh, Rohit Abstract: Metal matrix composites (MMCs) are replacing many conventional materials because of their superior properties such as high toughness, high specific strength, workability at elevated temperature, high stiffness etc. Metal matrix composites (MMCs) have become common engineering materials and are designed and manufactured lbr various applications including automotive components, sporting goods, aerospace parts. The growth in composite usage also came about because of increased awareness regarding product performance and increased competition in the global market. 13ut these MMCs are very difficult to machine due to abrasive nature of reinforcement. This abrasive nature of reinforcement results in higher cutting forces and accelerated tool wear. Therefore in this report an attempt has been made to investigate the machining characteristics of hybrid MMCs. In this experimental investigation, drilling experiments were conducted on Al/I O%SiC, Al/I O%SiC/l %Gr and Al/I O%SiC/3%Gr hybrid composites, with the help of 1-ISCo twist, lISCo step and HSCo TiN coated drills. All types of MMCs were fabricated using stir casting method. The efThct of variables like feed, cutting speed, drill type and %of graphite on the thrust force, surface finish and torque has been studied. Results indicate that small addition of graphite reduces the thrust force in all types of MMCs. The results show that the output variables are greatly influenced by the feed rather than cutting speed for all cutting conditions for all types of MMCs. Also the surface roughness values of graphitic MMCs were slightly more than Al/lO%SiC. The graphitic MMCs have better machinability than those reinforced with SiC alone.

2013-06-01T00:00:00Z Kumar, Ravinder http://localhost:8081/jspui/handle/123456789/17964 2025-07-09T12:42:39Z 2013-06-01T00:00:00Z

Title: ELECTRIC DISCHARGE HOLE GRINDING IN METAL MATRIX COMPOSITES Authors: Kumar, Ravinder Abstract: Metal matrix composites (MMCs) are playing a very important role in industrial growth because of their superior properties such as high toughness, high specific strength, high temperature resistance, high stiffness etc. The superior properties of these materials cause the difficulty in their machining. In order to achieve an economic machining of hybrid MMC (HMMC), non conventional machining is the best alternative. This report explains the machining of hybrid MMC with three processes namely Electric discharge cutting (EDC), Electric discharge drilling (EDD) and Electric discharge hole grinding (EDHG). Electric discharge cutting (EDC) process is one of the recently developed processes for the enrichment of capabilities of discharge machining. Experimental studies have been conducted on hybrid metal matrix composite (HMMC) with input parameters as current, pulse on-time and flushing pressure, keeping other parameters constant. Material removal rate of developed EDC process has been evaluated through standard test procedures. It has been found that the EDC based process is quick as compared to the conventional cutting processes. Electric discharge drilling has been carried out on an Al based hybrid MMC. The objective of this work is to study the effect of input variables (i.e. current, duty factor, tool speed and flushing pressure) on the material removal rate (MRR), tool wear rate (TWR) and surface roughness (SR). Design of experiments has been employed using response surface methodology (RSM) and through holes have been drilled by using the rotary tool electrode. The experimental results show that the input parameters have significant effect on MRR. TWR and SR. Electric discharge Hole Grinding (EDI-IG) is a combination of Electric discharge machining and mechanical grinding. A16063/SiC/Al203/Gr HMMC was used as a workpiece material and through holes were drilled by using rotary copper tool electrode followed by EDHG. The objective of this study was to investigate the effect of EDl-lG operation on the surface roughness of the hole with input parameters as current, duty factor, tool speed and flushing pressure. From the experimental results. it was found that the process is very effective to produce a finished hole. The grinding action of the process is clearly visible in scanning electron microscopic (SEM) image.

2013-06-01T00:00:00Z Ningala, Rakesh Babu http://localhost:8081/jspui/handle/123456789/17963 2025-07-09T12:42:30Z 2013-06-01T00:00:00Z

Title: CHARACTERIZATION OF MMC's DEVELOPED USING DIFFERENT MOLDING MATERIAL Authors: Ningala, Rakesh Babu Abstract: Metal Matrix Composites (MMCs) constitute an important class of design and weight-efficient structural materials that are encouraging every sphere of engineering applications. In the present work lOwt% SIC particulate reinforced A16063 matrix composite have been fabricated using two types of molding material like metallic mold and green sand mold through stir casting process. The Mechanical properties like tensile strength, impact strength, microstructure and hardness test conducted on both the samples taken from casted composites using two molding materials has been presented briefly. The tensile test conducted, results are plotted and it is concluded that the MMC obtained using metallic mold has better tensile strength. Microstructure of the resulting composites was studied by using metallographic testing, the results demonstrated that the distribution of reinforcement particles is reasonably uniform in metallic mold composite. When compared with sand mold composite. However, some porosities are observed in few areas due to the absorption of hydrogen gas during mechanical stirring and lack of lk wettability of the reinforcement particles. The impact strength of composite obtained using metallic mold shows a good strength than in composite from sand mold. Microhardness test results revealed, that the hardness in MMC obtained from metallic mold has slightly higher than in MMC obtained from green sand mold.

2013-06-01T00:00:00Z