Enhanced Strength, Nanolayered SiC for Micro-Gas Turbine Portable Power Generation

Period of Performance: 12/17/1998 - 06/17/1999

$69.6K

Phase 1 SBIR

Recipient Firm

Hyper-therm High-temperature Composites,
18411 Gothard Street, Unit B
Huntington Beach, CA 92648
Principal Investigator

Abstract

Micro-gas turbine devices may offer the potential for power densities equivalent to today's large-scale power generation in small man-portable units. Successful implementation of such devices is dependent on the development of a refractory material capable of operating at high temperatures and extremely high stress levels. Semiconductor micro-fabrication techniques combined with chemical vapor deposited (CVD) silicon carbide process technology is being explored for producing MEMS-type turbine rotors. The fabrication of relatively thick (100-500 micron) devices is currently limited by the strength, residual stresses, and inadequate conformal coverage that is attributable to the columnar grain growth of thick vapor-deposited SiC. This Phase I program proposes to solve these limitations by producing a Nanolayered CVD SiC. Nanolayering of the CVD SiC structure is expected to result in enhanced strengths due to reduced grain size. The reduced grain size is critical as feature dimensions in potential high temperature MEMS decrease in scale. Nanolayering of CVD structures has also been demonstrated to improve surface replication as compared to the conventional, monolithic CVD material due to the elimination of columnar grain growth. This program will fabricate nanolayered CVD SiC materials and compare the microstructural and mechanical behavior of these materials to conventional CVD SiC. BENEFITS: Nanostructured ceramic materials IS an emerging class or materials that may be the enabling technology for the fabrication of refractory MEMS devices such as the micro-gas turbine or other high temperature, wear resistant MEMS (i.e. bearings, sensors, actuators). Potential applications include high temperature, corrosion/erosion resistant coatings, high strength oxidation protective coatings, ultra-hard cutting tool materials and coatings.