Study of the Cryogenically Cooled Electrode Shape in Electric Discharge Machining Process

Authors: Vineet Srivastava, Pulak M. Pandey

Abstract:

Electrical discharge machining (EDM) is well established machining technique mainly used to machine complex geometries on difficult-to-machine materials and high strength temperature resistant alloys. In the present research, the objective is to study the shape of the electrode and establish the application of liquid nitrogen in reducing distortion of the electrode during electrical discharge machining of M2 grade high speed steel using copper electrodes. Study of roundness was performed on the electrode to observe the shape of the electrode for both conventional EDM and EDM with cryogenically cooled electrode. Scanning Electron Microscope (SEM) has been used to study the shape of electrode tip. The effect of various parameters such as discharge current and pulse on time has been studied to understand the behavior of distortion of electrode. It has been concluded that the shape retention is better in case of liquid nitrogen cooled electrode.

Keywords: cryogenic cooling, EDM, electrode shape, out of roundness.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1085583

References:

[1] K. H. Ho, S. T. Newman, "State of the art electrical discharge machining (EDM)," Int. J. Mach. Tools & Manuf., vol. 43, pp. 1287-1300, 2003.
[2] N. M. Abbas, D. G. Solomon, M. F. Bahari, "A review on current research trends in electrical discharge machining (EDM)," Int. J. Mach. Tools & Manuf., vol. 47, pp. 1214-1228, 2007.
[3] P. K. Mishra, Nonconventional Machining; Narosa Publishing House, London, 1997, ch.8.
[4] H. Ramasawmy, L. Blunt, "Effect of EDM process parameters on 3D surface topography," J. Mat. Process. Tech., vol. 148, pp. 155-164, 2004.
[5] A. Ozgedik, C. Cogun, "An experimental investigation of tool wear in electric discharge machining," Int. J. Adv. Manuf. Tech., vol. 27, pp. 488-500, 2006.
[6] G. C. Onwubolu, A note on "surface roughness prediction model in machining of carbon steel by PVD coated cutting tools," Amer. J. App. Sci., vol. 2 no. 6, pp. 1109-1112, 2005.
[7] N. R. Dhar, S. Paul, A. B. Chattopadhyay, "Role of Cryogenic Cooling on Cutting Temperature in Turning Steel," Trans. of ASME, vol. 124 no. February, pp. 146-154, 2002.
[8] F. J. da Silva, S. D. Franco, A.R. Machado, E. O. Ezugwu, A. M. Souza Jr., "Performance of cryogenically treated HSS tools," Wear, vol. 261, pp. 674-685, 2006.
[9] S. Paul, A. B. Chattopadhyay, "A study of effects of cryo-cooling in grinding," Int. J. Mach. Tools & Manuf., vol. 35 no. 1, pp. 109-117, 1995.
[10] K. V. B. S. K. Kumar, S. K. Choudhury, "Investigation of tool wear and cutting force in cryogenic machining using design of experiments," J. Mat. Process. Tech., vol. 203 no. 1-3, pp. 95-101, 2008.
[11] A. A. Khan, M. I. Ahmed, "Improving tool life using cryogenic cooling," J. Mat. Process. Tech., vol. 196, pp. 149-154, 2008.
[12] D. Kim, M. Ramulu, "Cryogenically treated carbide tool performance in drilling thermoplastic composites," Trans. N. Amer. Manuf. Res. Inst. SME, vol. 32, pp. 79-85, 2004.
[13] S. Abdulkareem, A. A. Khan, M. Konneh, "Reducing electrode wear ratio using cryogenic cooling during electrical discharge machining," Int. J. Adv. Manuf. Tech., vol. 45, pp. 1146-1151, 2009.
[14] Vineet Srivastava, Pulak M. Pandey, "Performance evaluation of EDM process using cryogenically cooled electrode," Accepted for publication in Mat. and Manuf. Process.
[15] K. L. Wu, B. H. Yan, F. Y. Huang, S. C. Chen, "Improvement of surface finish on SKD steel using electro-discharge machining with aluminum and surfactant added dielectric," Int. J. Mach. Tools & Manuf., vol. 45, pp. 1195-1201, 2005.
[16] Y. C. Lin, C. H. Cheng, B. L. Su, L. R. Hwang, "Machining Characteristics and Optimization of Machining Parameters of SKH 57 High-Speed Steel Using Electrical-Discharge Machining Based on Taguchi Method," Mat. and Manuf. Process., vol. 21, pp. 922-929, 2006.
[17] K. M. Patel, Pulak M. Pandey, P. Venkateswara Rao, "Determination of an Optimum Parametric Combination Using a Surface Roughness Prediction Model for EDM of Al2O3/SiCw/TiC Ceramic Composite," Mat. and Manuf. Process., vol. 24, pp. 675-682, 2009.
[18] M. P. Samuel, P. K. Philip, "Powder metallurgy tool electrodes for electrical discharge machining," Int. J. Mach. Tools & Manuf., vol. 37 no. 11, pp. 1625-1633, 1997.
[19] M. M. Rahman, M. A. R. Khan, K. Kadirgama, M. M. Noor, R.A. Bakar, "Experimental Investigations into Electrical Discharge Machining of Stainless Steel 304," J. App. Sci., vol. 11 no.3, pp. 549- 554, 2011.
[20] Y. Chen, S. M. Mahdavian, "Parametric Study into Erosion Wear in a Computer Numerical Controlled Electro Discharge Machining Process," Wear, vol. 236, pp. 350-354, 1999.