Published: 
By  Karen Walker

The National Science Foundation awarded a four-year, $1.75 million grant to a team of researchers from the University of Virginia and Duke University to develop materials that can withstand the extreme stress and heat of turbine engines. Elizabeth J. Opila, director of the Rolls-Royce University Technology Center on Advanced Materials Systems and professor of materials science and engineering and mechanical and aerospace engineering at UVA, leads the team. She is joined by Patrick E. Hopkins, UVA professor of mechanical and aerospace engineering; Jon Ihlefeld, UVA associate professor of materials science and engineering and electrical and computer engineering; and Cormac Toher, assistant research professor of mechanical engineering and materials science at Duke University. Turbine engines used for power and propulsion gain efficiency when operating at higher temperatures. Today's engines have hit a ceiling, however, in the temperatures they can withstand. The grant award for collaborative research, from the National Science Foundation's Designing Materials to Revolutionize and Engineer the Future project, aims to raise the ceiling by accelerating discovery of high-entropy silicates for extreme environments. The UVA-Duke team will design new coatings to enable higher temperature turbine operation. Their method innovates current approaches to coatings, which rely on a single rare-earth element in the silicate, a base material. They hypothesize that a mix of some combination of the 15 rare-earth elements in the silicates will optimize desirable coatings properties, including low thermal conductivity and high stability in reactive turbine engine environments. Their challenge is to find the right recipe. The exponential number of combinations makes this type of experimentation impractical for field research. They will instead employ computational models to learn and predict how material properties will change with each variation of the composition. Ihlefeld brings a high-end materials processing capability using gases, liquids and solids as precursors to make the coating materials. Opila and Hopkins will then test the materials, gaining knowledge of their properties. Their experimental results will feed Toher's computational model, which compares properties based on first principles such as bond energies, to make a prediction about the performance of a specific composition. Their agile development approach creates a positive feedback loop between a novel processing model and the materials system. This investment in new modeling computation methods can extend theoretical knowledge of rare-earth silicates into other materials systems.