Graphite Fiber Oxidation
Abstract
In order to improve the low interlaminar shear strengths which hinder widespread use of epoxy composites made from high modulus graphite fibers, an investigation was made of fiber surface treatments. Treatments of the fibers with various oxidizing systems was found to increase composite interlaminar shear strengths as much as twofold. Among the oxidizing agents studied, concentrated nitric acid was the most effective in increasing fiber-resin adhesion without significantly decreasing fiber strength. Exposure of the fiber to low pressure oxygen in the presence of an rf plasma was also an effective treatment. The mechanism by which fiber oxidation improves composite shear strength appears to be related both to an increase in fiber surface area and to an alteration of the nature of the surface resulting from the attachment of oxygen-containing functional groups.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 28, 1969
- Accession Number
- AD0863536
Entities
People
- John C. Goan
Organizations
- Naval Ordnance Laboratory