Weld Repair of Titanium Alloys for Turbine Engine Applications

Integrally Bladed Rotors – IBRs – are an important part of current and future military aeroengines. The use of IBR allows lower weight rotors with decreased drag and improved compressor efficiency. Repair of these parts however is currently problematic. The overarching objective of the Phase II work is to build upon the successful proof of principle conducted in Phase I and to build, test and validate a prototype for Titanium Gas Metal Arc Welding (GMAW) for IBR weld repair. This project will build upon the successful Phase I work by first developing welding parameters for smaller diameter wire enabling even finer weld geometry and hence repairs on smaller areas. Then, a novel monitoring and control methodology known as In – Process quality Assurance – IPQA – will be implemented to sense and control vital aspects of the welding process not possible with current approaches. Lastly, this advanced monitoring and control will be integrated with commercial power supplies to provide a prototype solution that can be transitioned to production in Phase III. Demonstration weld repairs will be made on prototypic mockup parts and metallurgical and mechanical properties will be evaluated to ensure suitability of this procedure for IBRs.