NASA 1996 SBIR Phase I


PROPOSAL NUMBER : 96-1 04.04-4000

PROJECT TITLE : Ceramic Matrix Composites with Net-Shape Single Crystal YAG Reinforcement

TECHNICAL ABSTRACT (LIMIT 200 WORDS)

Oxide fiber - oxide matrix type of ceramic matrix composites (CMCs) are candidate materials for turbine engine components operating at temperatures up to 1700íC. Polycrystalline oxide fibers however, lack the creep resistance required at that temperature. Currently available (commercial and experimental) oxide single crystal fibers have large diameter (~125 mm), are extremely expensive and are subject to damage and strength reduction during handling and preforming.

Foster-Miller proposes an innovative method to fabricate CMCs with net-shape single crystal yttrium aluminum garnet (YAG) reinforcement preforms. Compared to hexagonal sapphire, YAG is less anisotropic due to its cubic crystal structure. The net shape of the preform will eliminate handling and related damage and strength reduction. Most importantly, the creep resistance of single crystal YAG is an order magnitude higher than that of sapphire.

The objectives of the proposed effort are to fabricate single crystal YAG reinforcement preforms; infiltrate with model matrix; fabricate test coupons; and characterize the coupons. In the following Phase II, the objective will be to fabricate and validate prototype turbine components. Thus, the innovation will result in strong, highly creep resistant, oxidation resistant, net-shape reinforcement with tailorable interface for metallic, intermetallic and oxide matrices as desired by the subtopic.

POTENTIAL COMMERCIAL APPLICATIONS
The technology developed under this Phase I program will lead to high performance, high temperature, and substantially improved CMCs that are low-cost and commercially viable. The areas which will most immediately benefit from the success of this technology include: advanced gas turbine engine components, rocket engines, and armor.
NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR
Dr. Prashant G. Karandikar
Foster-Miller, Inc.,
350 Second Avenue,
Waltham, MA 02154-1196
NAME AND ADDRESS OF OFFEROR
Foster-Miller, Inc.,
350 Second Avenue,
Waltham, MA 02154-1196