Engine Test and Post Engine Test Characterization of Self-Sealing Ceramic Matrix Composites for Nozzle Applications in Gas Turbine Engines

Abstract

The advancement of self-sealing ceramic matrix composites offers durability improvements in hot section components of gas turbine engines. These durability improvements come with no need for internal cooling and with reduced weight. Building on past material efforts, ceramic matrix composites based on either a carbon fiber or a SiC fiber with a sequenced self-sealing matrix have been developed for gas turbine applications. The specific application being pursued on this effort is an F100-PW-229 nozzle seal. Full design life ground engine testing has been accomplished with both material systems. The ground testing has demonstrated a significant durability improvement from the baseline metal design. Residual properties are being determined for both systems by extracting tensile and microstructural coupons from the ceramic matrix composite seal. Nondestructive interrogation showed no material degradation and was used as a guide in setting cutting diagrams. The results from this effort will be presented along with documentation from flight test efforts.

A Global Approach to Fiber nD Architectures and Self‐Sealing Matrices: From Research to Production

“…This again demonstrates that the sequenced SSM provides an efficient protection of the material. This also shows that the stresses and temperatures seen during engine tests are within the material potential capability and confirms the design stress analysis 9 …”

Electrical resistivity monitoring of a SiC/[Si-B-C] composite under oxidizing environments

“…The estimated theoretical ratio and the experimental one are very close, which strongly supports the theoretical global approach previously described. Regarding the SM test (static fatigue, moist air), the ER increase is actually closer to be depending on t 3 oxygen diffusion may also be involved in the advance of the oxidation front. The following conclusions can be highlighted :…”

“…SiC/SiC based Ceramic Matrix Composite materials are promising materials for applications in high-temperature jet engines due to their excellent thermo-mechanical properties under oxidizing environments (high strength, toughness and creep resistance) [1][2][3][4][5]. Their introduction in aeronautical engines should enhance the thrust efficiency by reducing weights and increasing the possible service temperatures.…”

Degradation mechanisms of a SiC fiber reinforced self-sealing matrix composite in simulated combustor environments

“…The oxidation of the PyC weak interphase can occur under dry air at a temperature lower than 500 • C and leads to interfacial degradations of SiC (f) /PyC (i) /SiC (m) . SiC (f) /PyC (i) /[Si, C, B] (m) composites with a sequenced self-sealing matrix have been developed 1,2 and investigated [3][4][5][6][7][8][9][10][11] to protect the PyC interphase against oxidation effects up to 1400 • C. The principles of the and SiO 2 15,17 can volatilize, respectively, at 600 and 1100 • C under water vapor-containing environments. This phenomenon can cause the self-sealing capability to degrade, thus reducing the lifetime of the SiC (f) /PyC (i) /[Si, C, B] (m) .…”