GTREO Seminar: Dr. Jamesa Stokes – NASA Glenn

Advanced Environmental Barrier Coating Testing and Development for Gas Turbine Engines

ABSTRACT:  Environmental barrier coatings (EBCs) are an enabling technology for the use of SiC-based ceramic matrix composites (CMCs) in next generation gas turbine engines. SiC-based CMCs are lightweight and have higher temperature stability than traditional nickel based superalloys. However, SiC is susceptible to rapid oxidation and recession due to high temperature reactions with water vapor and other combustion species. Thus, EBCs were developed to protect these components and extend operating lifetime. In the extreme engine environment, EBCs must be able to withstand a variety of damage mechanisms and the synergies of degradation between them. This presentation will provide an overview of NASA Glenn Research Center, current aeronautics research, and an introduction to EBC failure modes and environmental durability test methods.

BIOGRAPHY: Dr. Jamesa L. Stokes is a materials research engineer in the Environmental Effects and Coatings Branch at the NASA John H. Glenn Research Center in Cleveland, OH. Dr. Stokes was born and raised in Atlanta, Georgia, and earned a high school diploma from the Lovett School. She continued her education at Auburn University, graduating Cum Laude with a bachelor’s degree of science in Physics in 2014. After graduating, she was awarded a J. William Fulbright Scholarship to conduct research in Stuttgart, Germany at the German Aerospace Center (DLR) Institute of Structures and Design, testing materials for heat shields and thermal protection systems under the supervision of Dr. Hannah Böhrk. Jamesa began Ph.D. graduate studies in 2015 at the Pennsylvania State University in the department of Materials Science and Engineering and completed her thesis research under the guidance of Dr. Douglas Wolfe in the Advanced Coating Department of the Applied Research Laboratory in 2019. Her graduate work focused on environmental barrier coatings for ceramic components in gas turbine engines and deleterious reactions with molten dust particulates from terrestrial sources like desert sand or volcanic ash. Her current duties as a materials research engineer at NASA’s Glenn Research Center in the Environmental Effects and Coatings Branch is to investigate the behavior of materials in extreme environments and to develop new ways to synthesize novel materials and advanced environmental protection systems.