Experimental Investigations on Sinking-EDM of Seal Slots in Gamma-TiAl

The increasing thermomechanical strength of modern materials for aerospace industry is accompanied by a challenging conventional machinability via cutting. This applies particularly to γ-TiAl alloys. In principle Electric Discharge Machining (EDM) processes are ideal for machining these materials, since they are independent of the material's mechanical properties and capable of machining complex structures. Seal slots in blades of compressors and turbines are one example. Manufacturers of EDM machine tools do not provide adapted technologies for processing γ-TiAl alloys, so end users are forced to configure and develop specific EDM processes by themselves. Therefore it is indispensable to develop fundamental knowledge about EDM-machining of γ-TiAl alloys. To acquire this knowledge the interdependency of material, process-related parameters and productivity is examined. The analysis is focusing on two different γ-TiAl alloys.