Silicon Nitride/Yttria: A Potential Gas Turbine Material,
Abstract
Yttria is an effective densification aid to silicon nitride due to the formation of (x)Si3N4.yY2O3.(z)SiO2 reaction product compounds which liquify at intermediate temperatures to promote sintering and then further react with Si3N4 to produce more refractory compounds. Significant increases in strength and stress-rupture properties have been demonstrated for the Si3N4-Y2O3 system in comparison with current Si3N4-MgO hot pressed materials, at temperatures exceeding 2400-2500 F. These are projected turbine inlet temperatures desired for high efficiency operation of gas turbines. Further studies on oxidation resistance, thermal shock, etc. are required to fully assess the overall capabilities of the Si3N4-Y2O3 materials system for operation in high temperature gas turbine environments. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1976
- Accession Number
- ADA025998
Entities
People
- George E. Gazza
Organizations
- United States Army Research Laboratory