Advances in the Development of Silicon Nitride and Other Ceramics

The use of silicon nitride for high temperature components in gas turbine engine and other heat engine applications continues to be sought due to the potential for significant improvements in both efficiency and emissions. However, low impact resistance and inadequate resistance to environmental degradation of current materials reduce its reliability for rotating and stationary components. Material improvements are needed to overcome these limitations. Potential and demonstrated methods to achieve improved fracture toughness, strength, and high temperature environmental resistance are reviewed.