Manufacturing Processes
M. Dastagiri; P. Srinivasa Rao; P. Madar Valli
Abstract
Electro Discharge Machining (EDM) is an incredibly recognizable machining for ticklishness profiles in ’difficult to machine ‘materials. In EDM, the material ejection of the cathode is cultivated through exact controlled electric pulse (the flash), which changes the metals of two terminals ...
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Electro Discharge Machining (EDM) is an incredibly recognizable machining for ticklishness profiles in ’difficult to machine ‘materials. In EDM, the material ejection of the cathode is cultivated through exact controlled electric pulse (the flash), which changes the metals of two terminals into dissolve and vaporize, as a result of the breakdown of the dielectric medium. The most commonly used dielectric media are kerosene, paraffin, glycerin, transformer oil, and EDM oil; all are derived from petroleum. These dielectric media undergo pyrolysis and carbon soot formation is deposited on work electrode, and sometimes carbon precipitates into work. To overcome these effects vegetable oils are tried as alternate dielectric media. Pongamia Pinnetta is abundantly available in most countries; and it is cheaper and non-edible. Pongamia Pinnata (PP) oil is extracted from plant seeds, and is blended with EDM oil and several experimentations are done to find its suitability. Operational variables with respect to input and output parameters are identified. Some of these are best EWR, MRR, TWR, and SR with applied current (I), pulse on time (Ton), and pulse off time (Toff) are the ones picked as the input process factors; because for the industrial application many machinists choose these three as the input parameters; and other is constant and picked under specific requirements only. After the successful completion of this experimentations, Pongamia Pinnata oil blends are fit for the industrial application using technique of order preferancing with similar to ideal solution [TOPSIS]. It is observed that no carbon soot formation takes place in the work component with PP oil as the dielectric fluid.
P. Kumar; M. Gupta; V. Kumar
Abstract
With the increased diversity of the customer demand and complexity of the product, Inconel 825 is widely used to meet the actual needs, especially in the aerospace industry. It is difficult-to-cut material because of its high toughness and hardness. The present research attempts to optimize the process ...
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With the increased diversity of the customer demand and complexity of the product, Inconel 825 is widely used to meet the actual needs, especially in the aerospace industry. It is difficult-to-cut material because of its high toughness and hardness. The present research attempts to optimize the process parameters of wire electric discharge machining during the cutting operation of Inconel 825. The wire electric discharge machining characteristics such as pulse-on time, pulse-off time, spark gap voltage, peak current, wire tension, wire feed are taken into consideration. The performance was measured in terms of material removal rate, surface roughness, and wire wear ratio. The central composite design of response surface methodology at an α value of ± 2 was employed to establish the mathematical model between process parameters and performance measures. A multi-objective particle swarm optimization algorithm has been used to find the optimal solutions called Pareto optimal solutions. It uses the concept of dominance to find the non dominated set in the entire population and the crowding distance approach to finding the best Pareto optimal solutions with a good diversity of objectives. The confirmation experiments of the multi-objective particle swarm optimization algorithm show a significant improvement in material removal rate (27.934 to 31.687 mm2/min), surface roughness (2.689 to 2.448μm), and wire wear ratio (0.027 to 0.030). SEM micrograph studies showed the number of cracks, pockmarks, craters, and pulled out material on the workpiece and wire electrode surface. Energy Dispersive X-ray analysis is performed to investigate the presence of elements on the work surface other than the base material.
A. Mahamani; S. Jawahar; J. P. Davim
Abstract
In-situ composites have gained the attention of worldwide researchers in the interest of their greater mechanical properties at the lower reinforcement ratio. Controlling the surface quality of components is a paramount task in the grinding process in order to withstand the creep and fatigue load at ...
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In-situ composites have gained the attention of worldwide researchers in the interest of their greater mechanical properties at the lower reinforcement ratio. Controlling the surface quality of components is a paramount task in the grinding process in order to withstand the creep and fatigue load at service conditions. The current effort is intended to examine the mechanism of surface generation in grinding AA6061-TiB2/ZrB2 in-situ composite under different reinforcement ratios, grinding parameters, and wheel materials. The analysis of results indicates that the grinding of the unreinforced alloy is complicated than the composites. Diamond wheel yields superior performance by generating lesser surface roughness and subsurface hardness at all grinding conditions. Among the various grinding parameters, grinding speed and grinding depth are more sensitive than other parameters. This experimental investigation helps to control the surface roughness and subsurface at various grinding conditions.
