Description: Under Phase II-E program, QuesTek will continue developing an enhanced tool material for friction stir welding of high melting point materials such as Ni-based superalloys. Phase II program has been focusing on fabricating tools with lab-scale production. Phase II-E program will further develop the technologies by producing tools with a larger quantity, establishing scalable production method of tools, and performing friction stir welding (FSW) with repeated plunge tests and a longer linear run for more realistic and relevant testing. QuesTek will keep working with Professor Rajiv Mishra from the University of North Texas, an active and renowned researcher in the area of friction stir welding, to fabricate and test the designed cermet materials. Concurrently, QuesTek will work with NASA Marshall Space Flight Center's Booster Element Office to develop high-performance steels for additive manufacturing (AM) which will be welded by FSW, which will be non-SBIR funded efforts. QuesTek will leverage both QuesTek’s expertise on steel design for AM and experiences from FSW tool development to develop steels for AM with properties of interests identified by NASA. This non-SBIR efforts to develop steels for AM include review of requirements for high performance AM substrate materials, design alloy compositions, and design validation through coupon build by AM and characterization. In addition, QuesTek will utilize the knowledge and insights from the FSW tool development to evaluate weldability by FSW of the developed steels.

Benefits: Regarding the FSW tool development, the efforts here would be invaluable in advancing the solid-state welding technologies at NASA in conventional-FSW, Hybrid-FSW, TSW of high melting point materials. Regarding the development of high-performance AM steels, the efforts here would be critical to allow NASA to rapidly manufacture component for aerospace application with less defects from AM and FSW process.

Regarding the FSW tool development, QuesTek has consulted multiple OEMs working in space-related research who have admitted that the availability of an FSW weld tool for high strength Ni-based alloys (the turbine engines, nozzles) would be of interest. Regarding the development of high-performance AM steels, potential markets include aerospace, defense, UAV, and other high-performance industries.