Laser metal deposition of TiAl alloys

Laser Metal Deposition (LMD) is a validated process for repairing aero engine parts and complete components. An increase of specific efficiency of aero engines is achieved by replacement of heavy parts out of Nickel Base Alloys in the HPC (High Pressure Compressor) and LPT (Low Pressure Turbine) sectors by lightweight parts out of TiAl Alloys in operating temperature ranges from 450 up to 700 °C. Due to the use of these upcoming new materials and non available repair techniques the market requires adequate R & D and repair development for specific parts and components. First results achieved within basic R & D of LMD of TiAl Alloys are presented. The determined suitable process parameter windows including suitable preheating temperature ranges to achieve defect free (crack free, pore free and bonding defect free) Laser Metal Deposits are shown. The influences of the process parameters on the results achieved by LMD arc discussed.