INFLUENCE OF POWDER SUSPENDED DIELECTRIC ON MRR & SURFACE ROUGHNESS IN EDM
Keywords:
Powder mixed dielectric EDM, MRR, Surface Roughness, Powder characteristicsAbstract
EDM is a non traditional machining process used to machine complex shape electrically material irrespective to its hardness by removing material through electrically discharges in the presence of dielectric fluid. Powder mixed EDM is modified process which is used to improve surface roughness in addition to improvement in machining efficiency of the process .This process can be applied to fine finishing machining which eliminate post production surface treatment Powder mixed EDM has a different mechanism from the conventional EDM which can improve the surface roughness and higher resistance to corrosion because of the diffusion of electrode (tool) and/or powder into the machined surface. Various powders materials like Aluminium (Al), chromium (Cr), copper (Cu) & sililicon carbide (SCi) has its different effects on material removal rate and surface finish. An intensive study is carried on the investigation done by the different researchers in the field of Powder mixed EDM. This paper presents the different effects of various powders & their characteristics on the efficiency of EDM when used as suspended particles in dielectric fluid.. The mechanism of EDM in Powder suspended dielectric fluid is also discussed. This paper mainly focused on the effect of powder concentration, the particle size, the particle density, and the particle receptivity, thermal conductivity of powder along with other machining parameters on MRR and surface roughness are discussed. Highest surface finish & MRR can be achieved by selection of proper powder characteristics & optimum parameters.
Downloads
References
C.J. Luis, I.Puertas, G.villa (2005) “Material removal rate and electrode wear study on EDM of silicon carbide, Journal of Material Processing Technology, 164-165: 889-896
Erden A, Bilgin S , ( 1980) Role of impurities in electric discharge machining in: Proceeding of 21st international machine tool Design Research conference, Macmillan, London : 345-350
Heuvelman C J, Horsten H. J , Veenstra P.C., (1971) An introductory investigation on Breakdown mechanism in electrodischarge machining Ann CIRP 22 : 49-50
Ho KH, Newman ST (2003) State of Art Electric Discharge Machining (EDM), Int j, Mach. Tools Manuf 43: 1287-1300
Jeswani ML (1981) Effect of addition of graphite powder to kerosene used as the dielectric fluid in electrical discharge machining Wear 70:133 -139 .
Klocke F., Lung D., Antonoglou G, Thomaidis D (2004) The effects of Powder suspended dielectrics on the thermal influenced zone by electric discharge machining with small discharge energies , Journal of Material Processing Technology 149 : 191-197
Ko-Ta Chiang, De Chang Tsai (2006) Effect of silicon particles on rapidly resolidified layer of Al-Si alloys in the elctro discharge machining process, int J Advance manuf Technol.
Kruth J.P. et al., (1998), In process Alloying of the white layer of a workpiece machined by Die sinking EDM , IJEM 3 : 33-38.
Luo V F, Zhang ZY, Yu CY (1988) Mirror surface EDM by electric field partially induced. Ann CIRP 37-1: 179-181.
Luo V. F (1997) The dependence of interspace discharge transitivity upon the gap debris in precision electro-discharge machining, journal of Material processing Technology, 68 : 121-131.
Masui K. et.al., (1995) , “ Surface modification of tool steel by alloying Method using EDM Process. Proc. Of ISEM XI : 419-426.
McGeough JA (1988) Advance methods of machining Chapman & Hall New York .
Mohri N et al, (1985) Mirror like finish by EDM in Proceedings of the 25th international symposium of machine tool design and research UK,
Mohri N, Saito N, Higashi M (1991) A new process of finish machining on free surface by EDM methods. Ann CIRP 40-1: 207-210.
Mohri N, Saito N, Suzuki M (1988), “Surface modification by EDM In ASME. (ed) Proc Winter Annual Meeting of The ASME-Research & Technological Development in non-Traditional Machining, Chicago, Vol.34, : 21-30.
Narumiya H, Mohri N, SaitoN, Otake H, Tsnekawa Y, Takawashi T & Kobayashi K, (1989) EDM by powder suspended working fluid , Proceeding of 9th International Symposium for Electrode machining, 5-8.
Pacas P, Henriques E (2001) Electrical Discharge machining with additive a way of mold steels non manual polishing. In lonardo PM(ed) Proc ist seminar in Innovative manufacturing Engineering –PRIME 2001 CIRP Genova 267-271.
Pacas P, Henriques E (2003) Influence of silicon powder mixed dielectric on conventional electrical discharge machining Int j Mach Tools manuf 43:1465-1471.
Paulo Pecas, & Elsa Henriques (2007), Effect of the powder concentration and dielectric flow in the surface morphology in electrical discharge machining with powder-mixed dielectric (PMD-EDM), Int.J. Adv Manufact Technol.:170-007: 1061-5.
Takawashi, T, Kobayashi H, Sakakibara T, Satio N, 1983 Study mirror surface finishing by planetary EDM, Proc Int. Symp. On Electro machining (ISEM-7), : 137-146.
Tzeng Y.F and Lee C.Y ( 2001) Effects of Powder Characteristics on Electro-discharge machining Efficiency, Int J adv Manuf Technol 17: 586-592.
Uno. Y Okada A and S Cetin (2001), Surface modification of EDMed surface with powder Mixed Fluid, 2nd international conference on Design and production of Dies & mold..
Wong Y. S., Lim L.C, Rehman Iqbal, & Tee W.M (1998) Near-mirror-finish phenomenon in EDM using powder-mixed dielectric journal of material processing Technology 79: 30-40.
Zeid O. A. Abu (1997) on the effect of electro-discharge machining parameters on fatique life of AISI D6 tool steel, journal of Material Processing Technology, 68 : 27-32
Zhao W.S., Meng Q.G, Wang ZL (2002), The application of research on powder mixed EDM in rough machining, journal of Materials processing Technology 129: 30-33..