Spark machining

Each bimetallic specimen thus obtained was cut into two pieces using an electric-spark machine. The surface of the Ni-Bi couples was first ground mechanically and then polished electrolytically using an Elypovist ... 

The bimetallic specimens obtained (Fig. 3.12a) were cut in two ways, as shown in Figs 3.12b and 3.12c. Use was made of an electric-spark machine to avoid their damage during cutting. Further specimen preparation, annealing procedure and investigational methods have already been described in Section 1.8.1 (for more detail, see also Refs 269-274). 

V.K. Jain, P.S. Rao, S.K. Choudhury, K.P. Rajurkar Experimental investigations into travelling wire electrochemical spark machining (TW-ECSM) of composites. Trans. AS ME, Journal of Engineering for Industry 113 (1991), p. 75. 

V.K. Jain, P.M. Dixit, P.M. Pandey On the analysis of the electrochemical spark machining process. International Journal of Machine Tools and Manufacture 39 (1999), p. 165. 

V.K. Jain, S. Adhikary On the mechanism of material removal in electrochemical spark machining of quartz under different polarity conditions. Journal of Materials Processing Technology 200 (2008), pp. 460-470. 

V.V. Nesarikar, V.K. Jain, S.K. Choudhury Travelling wire electrochemical spark machining of thick sheets of Kevlar-epoxy composites. Proceedings of the Sixteenth AIMTDR Conference (1994), pp. 672-677. 

In an electrotransport purification study Jordan et al. (1974) grew a Gd crystal 0.6 cm diameter by 2.5 cm long which had a resistance ratio of 250. A small sphere approximately 0.3 cm diameter was spark machined from this crystal, polished and etched. X-ray Laue patterns of the sphere showed it to have a maximum mosaic spread of approximately 1 minute of arc. 

After received high temperature deformation, the gauge part of the specimen ( 5xl3xlmm) was cut out with a spark machine and prepared as the deformed sample for magnetic annealing. A helium free superconducting magnet-installed heat treatment system (made by Sumitomo Heavy Machine Corporation, the maximum... 

L. R. Simpson and M. E Foltz, LLNL Small-scale Static Spark Machine Static Spark Sensitivity Test, LLNL Report UCRL-ID-135525 (Aug. 1999). 

The element has a metallic, bright silver luster. It is relatively stable in air at room temperature, and is readily attacked and dissolved, with the evolution of hydrogen, but dilute and concentrated mineral acids. The metal is soft enough to be cut with a knife and can be machined without sparking if overheating is avoided. Small amounts of impurities can greatly affect its physical properties. 

An attraction of the ECAM technique is the very fast rates of metal removal attainable by the combined effects of sparking and ECM. Eor example, in comparison to hole drilling rates for EDM and ECM, respectively 0.1 and 5.0 mm/min, rates of 15-40 mm/min may be achieved by ECAM. The ECAM technique can be appHed in all the ways discussed for ECM, thus surfaces can be smoothed and ddUed. Turning is also possible, as is wire machining (17). 

An explosion-proof machine is a totally enclosed machine whose enclosure is designed and constructed to withstand an explosion of a specified gas or vapor which may occur within it and to prevent the ignition of the specified gas or vapor surrounding the machine by sparks, flashes or explosions of the specified gas or vapor which may occur within the machine casing. 

A dust-ignition-proof machine is a totally enclosed machine whose enclosure is designed and constructed in a manner which will exclude ignitable amounts of dust or amounts which might affect performance or rating, and which will not permit arcs, sparks, or heat otherwise generated or liberated inside of the enclosure to cause ignition of exterior accumulations or atmospheric suspensions of a specific dust on or in the vicinity of the enclosure. 

The nickel-chrome alloy is available from the Dunlop Aviation Group and has the trade name of Retimet . Retimet is suitable, although its affinity for the organic phase is greater than for the aqueous phase. In order to produce approximately equal affinity for each phase the discs were gold plated for 10 min using a current of 300 mA. It is preferable that the alloy is shaped so that the pore structure is maintained on the surface after machining. Spark erosion is used to shape the material. 

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