Date of Award
Master of Science
Department of Aeronautics and Astronautics
Marina B. Ruggles-Wrenn, PhD
The tension-tension fatigue behavior of two oxide-oxide ceramic matrix composites (CMCs) was investigated at 1200°C in laboratory air and steam. Both composites consist of a porous oxide matrix reinforced with laminated, woven mullite/alumina (NextelTM720) fibers. The first composite had an alumina matrix, while the second had an alumina-mullite matrix. First, we assessed the effects of incorporating mullite into the matrix material on fatigue performance by studying the tension-tension fatigue behavior of alumina-mullite matrix CMC. Second, we evaluated the effects of effusion holes on the alumina matrix CMC's fatigue performance. Specimens containing an array of 17 effusion holes of 0.5-mm diameter were tested in tension-tension fatigue. The fatigue run-out was set to 100,000 cycles. All specimens that achieved fatigue run-out were subjected to tension tests to failure in order to measure the retained tensile properties. Fracture surfaces of the tested specimens were examined, damage and failure mechanisms are discussed.
DTIC Accession Number
Cabri, Anthony R., "Fatigue of Two Oxide/oxide Ceramic Matrix Composites at 1200°C in Air and in Steam. Effect of Diamond Drilled Effusion Holes" (2021). Theses and Dissertations. 4973.