Role of Interfacial Debonding and Matrix Cracking in the Effective Thermal Diffusivity of Alumina‐Fiber‐Reinforced Chemical‐Vapor‐Infiltrated Silicon Carbide Matrix Composites

Abstract

The thermal diffusivity of a biaxial weave alumina‐fiberreinforced chemical‐vapor‐deposited (CVD) SiC composite heated to 1500°C, which is above the manufacturing temperature, was found to exhibit an increase for heat flow parallel to the fiber plane, whereas a decrease was observed perpendicular to the fiber plane. The increase parallel to the fiber plane was thought to be due to the annealing of the fibers and matrix. The decrease perpendicular to the fiber plane was found to be the result of interfacial debonding and matrix cracking within the plane of the fibers.