A method for processing a workpiece of a nonconductive material, in particular diamonds, by spark erosion

摘要

1452218 Spark eroding diamonds PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd 28 Jan 1974 [7 Feb 1973] 03834/74 Heading B5E [Also in Divisions B3 and C7] In a method of machining an electrically non- conducting workpiece, e.g. diamond, by spark erosion, the dielectric liquid contains a surfaceactive material and from 0À5 to 10% by volume of a solubilized aqueous electrolyte solution. The dielectric which may comprise petroleum, kerosene, carbon, tetrachloride, trichloroethylene, tetraline or olive oil and paraffin oil, may contain an electrolyte solution consisting of sodium hydroxide or sulphuric acid solution. The surface active material comprises an alkylammonium salt, an amine salt, an alkylamine soap, a sulphosuccinate, an alkylaryl sulphonate or a material containing a polyoxyethylene and an alkyl or alkylaryl chain. A tungsten wire may constitute the spark erosion electrode.