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Electrical discharge machining (EDM) is a non-conventional process utilized for machining electrically conductive materials which cannot be machined by conventional processes. This paper is focused on modeling and optimization in electrical discharge machining (EDM) of UNS T30407 steel. The variables such as pulse on time (Ton), pulse off time (Toff), and current will influence the material removal rate (MRR) and surface roughness (Ra) which were taken as response variables. Experimental data were collected as per the central composite design (CCD) matrix of response surface methodology (RSM) approach and mathematical models have been developed for both the response variables. The analysis of variance (ANOVA) was employed to determine the significant machining parameters and optimize the input parameters for both the responses (MRR and Ra). The statistical adequacy of the models is tested with the help of ANOVA. The optimum parametric combination for maximum MRR and smaller Ra (highest surface finish) was found. The surface characteristics of the machined surface were investigated by a scanning electron microscope (SEM).

Electrical Discharge Machining (EDM) is the one of the earliest nontraditional machining processes. Today, many parts used in the aerospace and automotive industries and in the final processes of surgical can be finished by the EDM process. The machining parameters mainly affect the economy of process. This work emphasizes to find the optimization of machining parameters using response surface methodology (RSM)by variation of peak current, pulse time variation so that good Surface Finish (SF) can be achieved with the optimum Material Removal Rate (MRR). It was concluded that with the increasing peak current and pulseon Time (Ton), MRR increases but the surface roughness also starts to increase resulted in poor surface finish whereas with decreasing the pulse off Time (Toff), the surface finish increases but MRR starts to decrease. During the experimentation, Tool Steel-D2 was selected as work specimen with the copper electrode. Surface micrography had been done for the deep analysis to see the effect of machining on the Tool Steel-D2. This study indicates towards the practical feasibility of optimized EDM parameters in multi response conditions. How to cite this article:Singh P, Singh L. An Experimental Investigation During Electric Discharge Machining of Tool Steel-D2. J Adv Res Mfg Mater Sci Met Engr 2019; 6(3&4): 1-7.

The material removal in finishing of precision parts and hard to reach regions comprises a standout amongst the most demanding and costly stages in a manufacturing process. The magnetic abrasive flow machining (MAFM) is one of the non-traditional machining techniques which can successfully manage these problems. The MAFM process provides excellent surface finish at comparative low cost. The objective of the present investigation has been to understand the mechanism of the material removal (MR) and roughness improvement rate (RIR) in MAFM on a non-magnetic, soft and ductile workpiece. Finishing fluid in this study contains iron particles as magnetic bonders and diamond particles as abrasive part in different mesh size. Experimentation was conducted on aluminum tubes to investigate the effect of the key parameters on the MR and RIR and was designed in central composite design (CCD) of response surface methodology (RSM). It has been found that magnetic flux density (MFD) and number of cycles have impact on material removal and surface roughness. Based on experimental results, regression analysis of MR and RIR has been performed. This analysis has been used to predict MR and RIR compared with the experimentally obtained results. Both were found in close agreement. Finished surfaces were also examined using the scanning electron microscope (SEM) to get the knowledge for the fine surface texture produced by MAFM.

The advanced ceramics have emerged as a successful alternative to the conventional materials used in ball bearing industry. However, extreme hardness and lower toughness of the ceramic balls make t...

In modern industry presently requirement of finely finished surface has been the major demand as per the technological advancements. in comparison to conventional machining methods the unconventional machining methods provide better surface finish .Magnetic abrasive finishing is a process which is able to remove the material at micro/nano from the metallic and non metallic surfaces . The magnetic abrasives play the major role in MAF. Literature reveals different techniques such as sintering, plasma, chemical etc. for manufacturing of bonded magnetic abrasives in present paper the bonded abrasives are prepared by sintering and is used for internal finishing of brass tubes. The rough bored brass samples are finely finished by newly developed magnetic abrasives and loosely bonded abrasives prepared by silicone gel and the comparison of performance was studied. The material removal rate was also studied.

The finishing of surfaces of some of the aerospace parts and medical equipments was required to be of the finest quality. This work described the finishing of micro holes of aluminium cylindrical tubular type work specimens by one of the non-traditional machining method of finishing, i.e., magnetic abrasive flow machining. The abrasive media used for finishing contains newly prepared diamond based bonded magnetic abrasives. These abrasives were prepared by mechanical alloying followed by annealing method. The performance of magnetic abrasive flow machining process was evaluated in terms of surface roughness improvement rate. The process variables were optimised by employing response surface methodology. The parameters which showed prominent effect on surface roughness improvement rate were extrusion pressure, magnetic flux density and number of cycles. It was found through the experiments that the optimum result was obtained when extrusion pressure was 800 psi, magnetic field density was 0.6, and number of cycles was 25, which depicts that surface roughness improvement rate after finishing was 72.72% (Ra 0.22 μm). The results were also confirmed by analysing through scanning electron microscopy.

The traditional edged tool for machining is uneconomical for harder and difficult to machine materials. In view of the seriousness of this issue, the newly unconventional fine finishing process i.e., magnetic abrasive flow machining (MAFM) has been developed. However, the major constraint in wide spread adoption of this technology is the exorbitant cost of magnetic abrasives, which acts as a cutting tool in MAFM. In this paper, to improve the finishing performance, iron (Fe) powder mixed with diamond abrasives were prepared as bonded magnetic abrasives. These magnetic abrasives were prepared by mechanical alloying followed by annealing of diamond abrasives of 52 μm grit size and Fe powder of 49 μm grit size. These abrasives were micro-structurally analysed. The results indicate that densification increases and porosity decreases with increasing temperature. Further it was clarified that the prepared bonded magnetic abrasives has potential performance as the new magnetic abrasives for fine finishing.

Electrical Discharge Machining (EDM) is a non conventional machining process capable of accurately machining parts with high hardness and of complex shapes. The sparks produced during the EDM process cause localized melting on the work surface. The formation of recast layer is very common on EDMed surfaces. The recast layer reduces the service life of the die or mould surfaces, especially under fatigue loads. In the present work, Magnetic Abrasive Finishing (MAF) process has been explored as a method to remove the recast layer formed on a EN 31 steel cylindrical specimen machined by EDM. MAF process is one of promising methods capable of removing the material at micro/nano level under gentle mechanical forces. The diamond based sintered magnetic abrasives have been used to machine the EDMed surface. The experimental results indicate that the EDMed surface of EN-31 steel can be successfully finished with diamond sintered magnetic abrasives. On the finished surfaces, no evidence of micro cracks, voids and recast layer has been seen. Moreover, an average improvement in the surface finish up to 80% over the initial surface finish has been obtained. The micro hardness measurement on MAFed surface shows that brittle and hard layer has been removed. SEM photographs indicate the success of MAF for removal of EDMed surface.Copyright © 2015 by ASME

With the advancements in various fields such as medical research, space research, robotics, and CNC machines, there is dire need of machining processes, which are capable of providing good surface finish in tight tolerances. Besides this, new materials are being developed to realize the need of present industry. The properties of some of the materials are such that they cannot be machined by conventional or traditional methods. A family of new machining techniques called nonconventional machining processes has been developed. These newly developed processes are helping the industry to attain the required degree of accuracy and surface finish. In contrast to these processes, the conventional machining processes have limited performance and productivity. Nonconventional processes are also capable of machining the hard to machine materials and intricate shapes.

With advancement of technology, finely finished surface is one of the major requirements of modern industry. Fine machining with conventional edged tools is uneconomical and sometimes impossible. Magnetic Abrasive Finishing (MAF) is one promising process which is able to remove the material at micro/nano from metallic and non metallic surfaces. The magnetic abrasives play vital role in MAF. Literature reveals different techniques such as sintering, plasma, chemical, etc. for manufacturing of bonded magnetic abrasives. In the present paper, the bonded magnetic abrasives prepared by a new technique called mechanical alloying have been successfully used for the internal finishing of the brass tubes. After rough boring operation, the inner surface of the tubes is finely finished by newly developed magnetic abrasives. Best surface finish obtained by using these magnetic abrasives is of the order of 9 nm.Copyright © 2012 by ASME

Modern aerospace and electronic industries make frequent use of the difficult to machine materials. The micro machining of these materials with conventional edged tool is uneconomical with poor quality of the surface. A relatively new micromachining technology based on magnetic assistance has been used in the recent past to produce quality surface finish on these materials. The magnetic abrasives play an essential role of cutting tools in these processes. However, the magnetic abrasives are not easily available as these are produced by special techniques. This paper highlights major existing technologies that are used to manufacture magnetic abrasives. Main performance characteristics of magnetic abrasives have also been reviewed as regards to micromachining of various surfaces.