Creating Productive Conditions for Electric Discharge Machining of Non-conductive Ceramics

摘要: Fabricating structures from non-conductive ceramic materials like silicon nitride (Si3N4) is difficult through traditional machining, but their applications are increasing in engineering field due to high hardness, low thermal conductivity and resistance oxidation. High electrical resistivity of such ceramics restricts the use electric discharge machining (EDM) on them. An assistive electrode together with graphite powder-mixed dielectric mixture hydrocarbon fluids was used create favourable conditions for deposition conductive layer SiAlON having 105 Ω cm resistivity. The experiments were conducted according Taguchi design. Analysis variance using signal-to-noise ratios showcased significant parameters optimal values material removal, wear size overcut. elemental composition sample confirmed carbon particles surface which has helped propagation sparking beyond exhaustion layer. SEM images presence deposited removal by spalling evaporation.