EDM is the most popular unconventional machining process. The present technology of EDM consists of a pulsed or capacitive type power supply in which the pulsed type power supply is more popular and effective. The following essential component of an EDM is its servo mechanism, which controls the gap between the electrodes and maintains the gap voltage. A low machining speed, complex power supply, and servo mechanism increase the cost of machining and the maintenance cost of an EDM machine. To resolve the above issues from the EDM, a novel servo mechanism has been developed, which is simple in design and low in cost and has the capacity to use direct current as a power source. The current work elaborates a brief description of the novel servo mechanism and its feasibility analysis. Pure DC power is employed with the conjunction of Maglev lucidity to refine the shortcomings of conventional micro EDM. The novel technology addresses the prime concerns of conventional micro EDMs and deficiencies such as the delayed response of mechanical actuators and a servo mechanism. The novel technology uses the logical arrangement of permanent magnets and electromagnets to address inadequacies such as short circuiting and arcing. The work outlook is to establish the viability of the novel Maglev EDM by a comparison with a similar range of parameters. The results on the novel technology showed an improved material removal rate (MRR), which was in the range of 76.6 μgm/min, whereas the specific energy and surface roughness were 33.4 Joule/microgram and 4.3 μm, respectively, while machining commercially pure titanium.

The demand of ultra-precision micro-machine tools is growing day by day due to exigent requirements of miniaturized components. High accuracy, good dimensional precision and smooth surface finish are the major characteristics of these ultra-precision machine tools. High-speed machining has been adopted to increase the productivity using high-speed spindles. However, machine tool vibration is a major issue in high-speed machining. Vibration significantly deteriorates the quality of micro-machining in terms of dimensional precision and surface finish. This paper describes a design methodology of a closed type machine structure for vibration minimization of a high-speed micro-milling center. The rigid machine structure has provided plenty of stiffness and the damping capability to the machine tool without utilizing vibration absorbers. The models of the machine structures have been generated and assembled in AutoCAD 3D. The performances of the integrated micro-milling machine tools were determined by finite element analysis. The best model has been selected and proposed for manufacturing. Additionally, simulation results were validated by comparing with experimental results. Eventually, after manufacturing and assembly, experiments have been performed and determined that the amplitude of vibration was approaching towards nanometer level throughout the working range of the high-speed spindle. The machine tool was capable to fabricate miniaturized components with fine surface finish.

Generation of high pressure and temperature has various applications in defence. Several techniques, viz flying plate method, collapsing of linear, convergence of detonation waves in solid expiosives, have been established in this connection. In the present paper, converging detonation waves in solid explosives, where variable heat of detonation is being added to the front, is studied, by using Whith"am's characteristics rule. Results are compared with those reported, elsewhere.

At present, the machining performance of the existing EDM technology depends upon the commonly used pulsed power supply and gap control mechanism. The complexity and the higher cost of the above said vital components, reflected in the product cost. A simple electrical circuit has been applied to control the voltage and the electric magnet so that the tool electrode can levitate over the workpiece at the desired distance (electrode gap). A prototype is fabricated with the DC power supply and the maglev levitation mechanism. To evaluate novel maglev EDM technology with the existing EDM technology, experiments were conducted on Ti-6Al-4V alloy with a brass tool. The discharge waveform of maglev EDM has shown the discharge voltage and current and the absence of short-circuit at high duty factor. A predictive model is formulated by dimensional analysis based on MRR and average surface roughness. The experimental result of conventional EDM from the literature were used to prepare the model. The maglev EDM is showing higher MRR and surface roughness than the prediction. Surface morphology showed similar surfaces as formed in EDM. The specific energy analysis showed that the developed maglev EDM performs in reported data range. It is noted that the proposed technology is in its early stage and the performance is significantly comparable with the existing technology. Therefore, it is expected that the research in this area may help to develop an economically sustainable alternative to the existing costly and complex EDM technology.

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