CMC Matrices Enabling Long Operational Lifetimes at Temperatures Above 2700°F

Silicon Carbide based ceramic matrix composites (CMCs) offer the potential to fundamentally change the design and manufacture of gas turbines to significantly increase performance and fuel efficiency over current metal-based designs. Physical Sciences Inc. (PSI) and the University of California Santa Barbara (UCSB will develop and utilize Integrated Computational Materials Engineering (ICME) tools that will help us design and fabricate enhanced SiC-based matrices capable of long term operation at 2700°F in the combustion environment. Our approach will build upon PSI"s and UCSB"s previously successful work in incorporating refractory and rare earth species into the SiC matrix to increase the CMC use temperatures and life-time capabilities by improving the protective oxide passivation layer that forms during use. We will realize near term benefits by creating physics based-materials and process models that qualitatively define methods of improving matrix properties and can feed into our development of ICME tools. In the Phase I program we will focus on performing experiments and developing models predicting the effect of phase distribution, grain size, chemical composition, matrix density, and surface flaws on the oxidation behavior of the CMC matrix. We will iteratively improve the CMC performance by optimizing the composition and characteristics of the additives.