SBIR-STTR Award

There is a need for a good structural ceramic material that can be used at high temperatures in the oxidizing and corrosive atmosphere of turbine engines and that can be formed economically to complex shapes with low weight. The objective of this research project is to investigate a new family of ceramic composite materials that may meet those requirements. It is based on chemically vapor deposited (CVD) silicon carbide as the matrix, reinforced by a ceramic textile preform. The preform is woven to net shape and infiltrated with silicon carbide in a gas phase reaction. This program includes the evaluation of several types of fibers and fabrics for such a composite; the fabrication of test samples; and testing to obtain thermal, oxidation, and mechanical property data.

In the Phase I SBIR program, the feasibility of fabricating fiber reinforced ceramic matrix composites via chemical vapor infiltration (CVI) was investigated. The goal was to identify processing techniques capable of yielding composite microstructures that could provide the desired properties (especially toughness) suitable for rotating and/or static turbine engine components at temperatures above 1100 degrees c. The phase i program demonstrated that it is technically feasible to produce a high temperature, non-brittle ceramic composite with good strength by chemical vapor depositing silicon carbide into continuous ceramic composite with good strength by chemical vapor depositing silicon carbide into continuous ceramic fiber preforms. The objective of the phase ii program will be to develop a CVI processed silicon carbide matrix composite material that can demonstrate the microstructual stability, oxidation resistance and thermal shock resistance sufficient to maintain strength and toughness properties to 1350 degrees c. The program will include fiber/matrix interface studies, ceramic fiber preform evaluation, chemical vapor infiltration process development and physical property characterization of the material.