Chemical vapor deposition (CVD) is widely used in processing of composites for a variety of high temperature applications. Variations of the technique include CVD on substrates, fibers, coating inside cavities and on complex objects, and infiltration within preforms, called chemical vapor infiltration (CFI). Sic, Si3n4, BN, carbon-carbon, SiC-SiC, C-SiC, and functionally gradient materials are some examples of composites processing using CVD and CVI. Our current knowledge of the process mechanisms, ability to optimize processes, and scale-up for large scale manufacturing is limited. In the proposed work, mathematical models appropriate for the description of transport phenomena, multicomponent effects, chemical reactions, surface processes, and infiltration within the numerical simulation code. Models for the linking of macroscopic transport phenomena to the microscopic material properties will also be considered. The proposed models and computer code will be used to study and optimize processes of commercial importance and relevance to Air Force missions. A graphical user interface (GUI) for the code will be developed to facilitate transfer of technology to the Air Force and private sector. The proposed STTR work will be conducted in collaboration with the University of Houston, who would address model development for transport within fibrous preforms and microscopic material characteristics.
Keywords: CHEMICAL VAPOR DEPOSITION, CHEMICAL VAPOR INFILTRATION, COMPOSITES, FUNCTIONALLY GRADIENT
