Fiber creep rate and high-temperature properties of SiC/SiC composites

[摘要] Optimization of the high-temperature structural properties of continuous silicon carbide fiber, silicon carbide matrix composites (SiC/SiC) requires a fundamental understanding of the relationship between fiber, matrix, and interface properties. Results of a study aimed at relating the fiber creep rate to the subcritical crack growth (SCG) rate and fracture properties of SiC/SiC composites have demonstrated that the crack growth rate in a bulk composite is controlled by the fiber creep rate. This result was demonstrated for Nicalon-CG and Hi-Nicalon fiber reinforced material where a 100 degrees C shift in the creep strength of the fiber resulted in a similar shift in the crack growth rate of the composite. Irradiation enhanced creep of SiC fibers and matrix must also be considered in the performance assessment of SiC/SiC composites. An estimate of the impact of irradiation creep of SiC fibers on the SCG of SiC/SiC will be presented. (C) 1998 Elsevier Science B.V. All rights reserved.

[发布日期] 1998-10-01

[效力级别]  Proceedings Paper