Electrical and Mechanical Properties of Intercalated Graphite Fibers.
Abstract
In order to understand the electrical and mechanical property changes which occur when graphite fibers are intercalated, it is essential that a better understanding of the properties of the fibers prior to intercalation be developed. Research aimed at elucidating the structure-property relationships in neat carbon and graphite fibers is presented. In particular, the changes with increasing heat treatment in both electronic and structural properties are discussed. The relative importance of crystallite size, three dimensional order, and the details of disordered regions between crystallites are demonstrated by analysis of: resistance versus temperature; piezoresistance; x-ray diffraction; and intercalation behavior. Crystallite size effects must be included in order to understand the electronic structure of the fibers studied here. Arguments which demonstrate the potential importance of the disordered regions between crystallites to the anamolous resistance-temperature behavior of low-modulus, high-strength fibers are presented. Three dimensional order is shown to increase continously with heat treatment. The piezoresistance of carbon and graphite fibers is discussed in terms of a simple polycrystalline model, and useful qualitative information on the parameters needed for modelling the elastic properties of these material is obtained.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1985
- Accession Number
- ADA155560
Entities
People
- H. A. Goldberg