Coolant side surface roughness on airfoil castings by electrical discharge machining (EDM)

摘要

The present invention involves a process for increasing coolant side surface roughness on castings such as airfoils, shrouds, nozzles or the like by electrical discharge machining (EDM). An EDM electrode is shaped to fill completely or a portion of a cavity in the casting, the electrode is then connected to an electric discharge machine, and the internal surfaces of the internal core cavity are then machined to form a roughened surface.