| 摘要 |
PURPOSE:To obtain an incombustible electric discharge machining liquid which causes no partial exhaustion of the electrode and permits an electric discharge machining improved markedly in machining speed by incorporating a specific block copolymer in an incombustible base liquid for electric discharge machining. CONSTITUTION:A block copolymer represented by the formula [wherein n is 1-25; and n/(m+p)=0.5-2.5], which is a copolymer of propylene oxide and ethylene oxide, is dissolved in an incombustible base liquid (e.g. water) for electric discharge machining to prepare an incombustible electric discharge machining liquid. By using the discharge machining liquid thus obtained, the rate of electrode exhaustion can be reduced below about 1%. Further, by dissolving the block copolymer of the formula, a substituted phenol (e.g. o-cresol) or/and an amine derivative (e.g. phenyl-alpha-naphthylamine) together in an incombustible base liquid, a further reduction in the rate of electrode exhaustion and improvement in the machining speed can be achieved. |
