Applied Mechanics and Materials Vols. 592-594

Abstract: Wire cut Electrical Discharge Machining is one of the important manufacturing process which is used to obtain desired shape using electrical discharge (or) by continuous sparking. This paper deals with wire cut EDM of D2 die steel using Zinc coated wire tool. Two conflicting objectives, surface roughness and kerf width, are simultaneously optimized. Experimentation was planned based on Taguchi’s L-9 orthogonal array. All the experiments has been conducted under different machining conditions of gap voltage, pulse ON time, and pulse OFF time. Wire feed, wire speed, resistance, wire tension, dielectric fluid pressure and cutting length are taken as fixed parameters. In this paper Gravitational Search Algorithm (GSA) is employed for optimising surface roughness and kerf width.

Abstract: Friction welding is an economical solid state joining process which has gained industrial acceptance for producing dissimilar joints with light weight applications. In this work continuous drive friction welding was employed to produce AA6061-T6/AA2024-T6 joints. The process parameters which influence the quality characteristics of the joint like the frictional pressure, upset pressure, rotational speed and burn off length were varied in three levels and the experimental trials were designed by Taguchi’s L₉ orthogonal array. Yield strength, ultimate strength and micro-hardness in the weld area were observed as the responses for the various trials. Weighted S/N (WSN) ratio was calculated for each trial by utilizing the weights generated by simulated annealing (SA) algorithm. The optimal levels were sorted out by taking the WSN ratio as a measure of performance and a confirmation experiment was conducted for validation. The results of ANOVA had revealed the significant contribution of upset pressure in affecting the quality characteristics.

Abstract: In this study, Sparking parameters specifically Current (I), pulse on time (t_on), pulse off time (t_off), spark gap and dielectric flushing pressure (P) are optimized with the consideration of multi responses such as Material Removal Rate (MRR) and Electrode wear Rate (EWR). The characteristic features of the Spark EDM process are explored through Taguchi L₁₈ orthogonal array design of experimental studies with various process parametric combinations. To optimize the above machining parameter, grey relation techniques are used. Based on the grey relation grade, optimum levels of parameters have been identified and major contribution of parameters is determined by ANOVA. Verification test is conducted to validate the test result.

Abstract: Abstract. This paper proposes an experimental investigation of the most influencing machining parameters like spindle speed, feed rate and depth of cut on CNC turning of three metals viz. 316L Stainless steel, EN24 alloy steel and Ti 6 Al 4V alloy. Fractional factorial design with orthogonal array [L₉ (3³)] is employed for the optimization of these turning process parameters. All experiments were carried out using EMCO CNC 250 Turn machine with carbide cutting tool. The comparison revealed that feed rate and depth of cut are the most significant turning factors on surface roughness followed by spindle speed for these three metals.

Abstract: Machining of composite materials is an important and current topic in modern researches on manufacturingprocesses. This paper presents the detailed experimental investigation on drilling Aluminium Silicon Carbideparticulate Metal Matrix Composite (Al-SiC –MMC). Experiments were carried out on Radial Drilling Machine.A plan of experiments, based on the techniques of Taguchi, was performed. The objective of this research is tostudy the effect of cutting speed, feed, diameter of cut, machining time on metal removal rate, specific energy,surface roughness, volume fraction and flank wear. The optimum machining parameters were obtained by Greyrelational analysis. Finally, confirmation test was performed to make a comparison between the experimentalresults and developed modelKeywords: Composite materials; drilling processes; Rey relational analysis Optimization

Abstract: The present study investigates the optimization of multiple responses in turning of EN-8 steel by the Taguchi and grey relational analysis. The performance characteristics considered are tangential force, feed force and radial force. Grey relational theory is adopted to determine the best process parameters that give lower magnitude of tangential, feed, radial forces and optimal cutting parameters. An orthogonal array L₁₈ is used for the experimental design. The setting of process parameters— nose radius, 0.8mm; cutting speed, 60.65 m/min; feed rate, 0.04 mm/rev; and depth of cut, 0.60 mm— has highest grey relational grade and therefore produces best turning performance in terms of cutting forces.

Abstract: In this study the process of Wire Electric Discharge Grinding was carried out with a precise, flexible and corrosion resistant submerged rotary spindle which was designed, fabricated and installed in a five axis CNC Wire Electric Discharge Machining in order to produce free form surfaces on micro rods. The tungsten was taken as a work material since it is hard to machine through conventional process. Based on the literature survey the following four factors such as the spindle speed, pulse off time, peak current and wire speed are considered for obtaining high diametrical accuracy. By Taguchi parametric design the array was designed and experimental trials were taken by machining an Ø2.0mm tungsten (W) pin to Ø0.40mm under various set of parameter combinations. The S/N ratio analysis was carried out to find the optimum machining parameters and significant parameters affecting the diametrical accuracy. The analysis of variance was used to analytically verify the significant parameters. Finally it is concluded experimentally and statically that the significant parameters affecting the diameter accuracy are spindle speed and pulse off time.

Abstract: In the present study AA5083 and AA6061 were welded using friction stir welding process by controlling the various welding parameters viz. rotational speed, welding speed and Tool axial force for two different tool profiles. Aluminum alloys 5083 and 6061 have similar properties and they both are widely used in marine industries and other transportation industries. In this work the effect of various parameters on the mechanical properties viz. tensile strength and impact strength were studied. In this study the Taguchi approach was used as a design of experiment to set optimum parameters. The experiments were done using Taguchi’s L9 orthogonal array. Analysis of variance test was also performed to obtain the effect of the parameters on the weld strength. Both DOE and ANOVA were performed using MINITAB software.

Abstract: Detonation gun spray coating method (D-Spray) is an effective method of coating process [4]. The surface property of material will be enhanced by deposition of coating powders such as metal oxides and ceramics like aluminium oxides, tungsten carbide, nickel chromium etc. which improves micro hardness, corrosion and wear resistant resistance property. This coating process is applicable in different engineering sectors such as aviation industry, marine industry, biomedical industry etc., In this Experimental study the Process parameter optimization of D-spray coating process with different coating powder was done by Taguchi design of experiment [2] and interrelationships among multiple response was analysed with Grey relation Analysis [2] in order to find the optimized processing conditions and to get higher quality of coating. Micro hardness Wear resistant, Surface roughness are the multiple responses estimated for various combinations of parameters and the optimum process parameters were obtained.

Abstract: The purpose of this research paper is focused on the analysis of optimum cutting conditions to get minimum surface roughness and minimal flank wear in turning SCM 440 alloy steel by Taguchi method. L₉ orthogonal array is designed to conduct the experiments. Experiments are conducted on supercut 5XL Lathe using coated carbide tool. The process parameters are cutting speed, feed and depth of cut. Surface Roughness and Flank wear are selected as the responses. Surface Roughness is measured using Mitutoyo Surface roughness tester and Flank wear is predicted using SEM images after the experiments. The results are analyzed using analysis of variance (ANOVA) method. The regression equations for the responses are determined and the probability plots are plotted and found satisfactory. The R-squared values are also calculated using analysis of variances and it is found that these values are close to the proximity level and satisfactory. Taguchi method is used to analyze the dominating parameters in minimization of surface roughness and minimization of flank wear.,