The fabrication of film cooling holes on turbine blade of aero-engine is always a difficult problem. In this paper

the EDM ECM hybrid machining method for small holes drilling is presented

in which electrical discharge machining (EDM) and electrochemical machining (ECM) occur simultaneously. According to experimental studies on the EDM ECM hybrid machining method

machining process phenomenon

waveforms of voltage and current were observed. The composition of processed product was analyzed

and the ratio of material removal by electrochemical dissolution was also calculated. Effects of different working fluid conductivities on tool electrode wear performances were studied. Machining qualities of small holes by hybrid machining and pure EDM were compared. The results of experiments indicate that the EDM ECM hybrid machining can effectively remove the recast layers on the side wall of the hole in the machining process. Thus

a novel way to machining the film cooling holes can be provided with high efficiency and free of recast layer. It also can be used for machining other small hole structures in aero-engine.