Additive Manufacturing of Superior Oxidation Resistance Titanium Alloy HOWMET-THOR™

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 nickel-base superalloys for service temperatures in between current titanium and nickel. Improvements to higher temperature capability 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 of about 1000°F is still the state-of-the-art. Current temperature requirements have pushed beyond the available Titanium alloys, forcing the only option of using high-density material resulting in increased fuel consumption. A novel titanium alloy HOWMET-THOR^TM was developed which exhibits superior oxidation resistance than any other currently available conventional titanium alloy. Additive manufacturing (AM) is an enabler for advanced structural components that could provide additional weight savings. This presentation provides an overview of laser powder bed AM of HOWMET-THOR^TM highlighting powder characteristics, example AM builds, post-AM thermal processing treatments, microstructure, and mechanical properties.