Gama-Titanium-aluminide (?-TiAl) is an intermetallic material, used in applications where high temperature is required. Compared to other materials, these alloys offer opportunities for substantial weight reductions, and compared to titanium alloys they offer better creep, oxidation resistance, and increased strength at elevated temperatures. ?-TiAl is typically used in a temperature range between 100 °C and 850 °C. In recent years, the efforts to improve ?-TiAl alloys processing and properties were concentrated on structural manipulation by thermo mechanical processing, innovative processing methods such as defect free casting or near net shape processing and surface properties improvement using surface engineering tools. In this project a new ?-TiAl alloy, containing Ti-Al-Nb-Ta-Cr-Ni, was obtained and analysed. In order to increase the ?-TiAl alloy performance two distinct research modules were planned in project’s frame: a thermo-mechanical processing module, able to conduct to crystalline grains refinement and a surface modification module by ionic implantation. After ionic implantation treatment, resulted surfaces showed superior properties reflected in increased corrosion and wear resistance.
The project’s WorkPackages contained research activities related to following specific innovative objectives:
- Design and synthesis of a new ?-TiAl alloy, exhibiting mechanical and structural properties able to assure it’s processing in advantageous technological conditions;
- New ?-TiAl alloy casting technology establishment, in order to obtain complex shape-defect free components;
- Thermo-mechanical processing technology design, at laboratory level, focused to obtain enhancements in mechanical properties and corrosion resistance;
- New ?-TiAl alloy surface treatments, using an innovative ionic implantation procedure, in order to improve mechanical and corrosion resistance at elevated temperatures.