Superior Oxidation Resistance Titanium Alloy ARCONIC-THORTM for Aerospace Applications

Next generation fuel-efficient jet engines are running hotter presenting a structural challenge for the exhaust systems and structures adjacent to the engines. A conventional and affordable titanium alloy with superior oxidation resistance provides significant weight reductions and associated cost savings by eliminating the need for high density material systems such as nickel-base superalloys for service temperatures in between current titanium and nickel, enabling major technology advancement in high temperature aerospace applications. Improvements in temperature capability of titanium alloys in the last 65 years have been incremental. Ti-6Al-2Sn-4Zr-2Mo (Ti-6242), introduced commercially in 1989, with maximum service temperature capability of 1000°F is still the state-of-the-art. Balance of alloy formulation and processing to achieve desired combination of performance without compromising producibility and affordability has been a major challenge in the development of high temperature Ti alloys. Current temperature needs are pushing beyond the available Ti alloys, forcing the only option of using high-density and expensive solutions for these applications, which increases the weight and is an underutilization of their capability.

Under an U.S. Air Force Metals Affordability Initiative project, a collaborative team comprising Arconic, Boeing and Honeywell was formed with the objective of focused maturation of a superior oxidation resistance Ti alloy ARCONIC-THOR^TM. Using an integrated product development approach, the team combined design, materials, manufacturing, and modeling for rapid maturation and implementation of this new Ti alloy. Building upon the detailed technical investigations conducted on sub-scale systems to optimize material and processing, full-scale components were fabricated using production heat lots on production equipment. Manufacturability assessments and coupon/element testing were performed to demonstrate the product readiness from development to production floor. Statistically significant test data were generated and an aerospace material specification AMS6953 for sheet was published.