Accession Number:

ADA025998

Title:

Silicon Nitride/Yttria: A Potential Gas Turbine Material,

Descriptive Note:

Corporate Author:

ARMY MATERIALS AND MECHANICS RESEARCH CENTER WATERTOWN MASS

Personal Author(s):

Report Date:

1976-01-01

Pagination or Media Count:

12.0

Abstract:

Yttria is an effective densification aid to silicon nitride due to the formation of xSi3N4.yY2O3.zSiO2 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

Subject Categories:

  • Ceramics, Refractories and Glass
  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE