Buckeye engineers awarded $1.97M to create new class of superalloys

Ohio State engineers are teaming up with NASA Glenn Research Center, GE Aerospace and the Air Force Research Laboratory to design superalloys with exceptional high-temperature properties. Such materials are critical for improving the efficiency of ultra-high temperature applications—such as jet engines and power generation system turbines—and reducing harmful carbon emissions.

Materials Science and Engineering Chair Michael Mills leads the team of researchers who received a four-year, $1.97 million grant from the National Science Foundation (NSF) for the project. The award is part of NSF’s Designing Materials to Revolutionize and Engineer our Future (DMREF) initiative to drive the design, discovery and development of advanced materials needed to address major societal challenges. 

“The MSE department at Ohio State has an international reputation for leading-edge research in materials for extreme environments, such as conditions found in advanced turbine engines for aerospace. While improving the specialized metallic materials needed for these applications brings a host of benefits, they are already highly optimized and so making advancements is a big challenge,” Mills said. “In this new DMREF program, we are harnessing our prior experience in superalloys with innovations in materials processing that have been enabled by a new additive manufacturing technique that opens the door for exploring a new class of oxide-reinforced alloys.”

The new superalloys are based on the concept that metals can be reinforced by uniformly distributing a small amount of ceramic oxide phases throughout the metallic matrix. The presence of such oxide reinforcements can make materials significantly stronger and help protect them against harsh, high-temperature environments.

The researchers will use a novel additive manufacturing approach pioneered at NASA Glenn Research Center to create oxide dispersion strengthened metallic materials. It involves a moving laser that melts and solidifies the metal and oxide powder, building up the material layer-by-layer. The project will further improve these materials by using additional strategies for strengthening the metals.

“The desirability of oxide dispersion strengthening (ODS) has been known for decades, but the traditional processing means used to create a fine distribution of oxide particles—mechanical alloying—is very time- and cost-intensive, while yielding undesirable variability in the resulting microstructures,” Mills explained. “The additive manufacturing process pioneered by NASA Glenn Research Center appears to provide an attractive, faster alternative that enables direct production of the desired microstructures. These materials will inherit additional strength from precipitation strengthening, a traditional approach to improving behavior in superalloys.”

Co-investigators on the project include Associate Professors Stephen Niezgoda and Calvin Stewart, who hold joint appointments in materials science and engineering and mechanical and aerospace engineering at Ohio State. Emmanuelle Marquis, a professor of materials science and engineering at the University of Michigan, is also a co-investigator. These researchers will work together to measure the mechanical and oxidation behavior of these new materials, characterize their microstructures and develop models linking processing to microstructure to properties. Alumnus Timothy Smith (PhD 2016, materials science and engineering) leads the effort to further develop the additive manufacturing process at NASA Glenn Research Center. GE Research Principal Engineers Laura Dial and Akane Suzuki are active industry participants and advisors on the program. Several colleagues at the Air Force Research Laboratories are also collaborating on the program, including Program Manager Todd Butler of the Materials and Manufacturing Directorate.

Researchers will generate new knowledge about the interaction between this new processing strategy, the resultant internal structure of the alloy and mechanical behavior of these new materials. This knowledge will be made accessible using a new artificial-intelligence framework that will enable the team to the optimize the alloys.

“The additive ODS processing route opens the door to rapid assessment of alloy behavior,” Mills said. “It enables, for the first time, the use of effective machine-learning approaches for alloy-microstructure-property optimization of novel ODS alloys.”

by Candi Clevenger, College of Engineering Communications, clevenger.87@osu.edu