Novel Molecular Sources for Dispersing Boron in Carbon-Carbon Composites
Abstract
Improving the oxidation resistance of carbon-carbon composites is key to expanding the use of this material system into higher temperature applications. While boron particles have been added to these materials to seal cracks in protective coatings, oxidation of the carbon matrix neighboring the boron particles seriously affects composite strength. This problem is exacerbate by a natural segregation of the boron particles to fiber rich areas of the composites. Carborane, a robust molecular source of boron, was used as the precursor for atomically dispersed boron in a phenolic derived carbon matrix. Modifications of the chemical structure of carborane were used to improve the solubility in phenolic. Additions of carboranes into the phenolic resins dramatically improved the oxidation resistance of the carbonized char. The char yield of the phenolic resin was also increased significantly.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 31, 1991
- Accession Number
- ADA246999
Entities
People
- Philip S. Chen
- Ward C. Stevens