One of the world's leading aircraft manufacturers is looking to a Tennessee Tech researcher to lead a collaboration focused on improving aircraft engine performance.

Ying Zhang

Ying Zhang, assistant professor of Mechanical Engineering, recently received a National Science Foundation grant totaling $330,000 through an initiative called Grant Opportunities for Academic Liaison with Industry.

Working with General Electric Aircraft Engines, located in Cincinnati, and Oak Ridge National Laboratory, Zhang will explore how to improve the ceramic coatings, commonly known as thermal barrier coatings, used to cool and prolong the life of aircraft engine components. The use of TBCs provides major reductions in surface temperature of metal components, which leads to improved durability and significant fuel savings.

"Typical commercial coatings consist of a ceramic coating applied to metal through a bond coat," says Zhang. "We are exploring a new bond coat system that can offer advantages of increased strength, better compatibility, improved stability and reduced manufacturing costs.

"Our goal is not to find a 'cure-all' type of bond coat to replace all others, but to identify a new custom-designed bond coat system that will perform well with the new family of superalloys that engine builders are using."

Ken Currie, director of the Center for Manufacturing Research, says Zhang's collaborative work proposes to tackle a complex issue.

"This topic of thermal barrier coatings is very difficult to solve, and it is fraught with challenges: the thickness, toughness and uniformity of the coating layer, compatibility of the coating with the substrate, and effect of defects in either the coating or substrate/coating interface," he says. "And we want to know how this material system behaves under a number of 'as used' conditions — heat, cold, cycling of temperatures, moisture, corrosives, vibration, impact, load stresses, and more."

Over a three-year period, GEAE will provide overall design guidelines and supply some materials to Zhang. Fabrication and some testing will take place at Tennessee Tech. ORNL will provide testing facilities and open its doors to students participating in the project.

"Dr. Zhang’s proposal is also unique in the way that she has incorporated graduate students into the project and utilized both the industry and ORNL personnel as cohorts to mentor and assist students with understanding measurement techniques as well as understanding the application environment of these material systems," adds Currie. "It makes for a 'lively experiment,' not just about materials but also the way we educate our graduate students."

TBC research is an example of a project that might not be fundamentally investigated if left to industry initiative alone. GOALI targets the high risk/high reward projects that focus on topics industry will not undertake. This, in turn, will afford new approaches to generic problems, innovative collaborations between university and industry educational programs, and direct transfer of knowledge from universities to industry.