Raman Study of Uncoated and p-BN/SiC-Coated Hi-Nicalon Fiber-Reinforced Celsian Matrix Composites, Part 1

摘要

Hi-Nicalon fiber reinforced celsian matrix composites were characterized by Raman spectroscopy and imaging, using several laser wavelengths. Composite Number 1 is reinforced by as-received fibers while coatings of p-BN and SiC protect the fibers in composite Number 2. The matrix contains traces of the hexagonal phase of celsian, which is concentrated in the neighborhood of fibers in composite Number 1. Some free silicon was evident in the coating of composite Number 2 which might involve a (BN + SiC yields BNC + Si) 'reaction' at the p-BN/SiC interface. Careful analysis of C-C peaks revealed no abnormal degradation of the fiber core in the composites.