High Performance Fibers
Abstract
A two and a half year ONR/ARPA funded program to develop a low cost process for manufacture of a high strength/high modulus sigma/E boron nitride (BN) fiber was initiated on 7/1/90 and ended on 12/31/92. The preparation of high sigma/E BN fibers had been demonstrated in the late 1960's by the PI using a batch nitriding of B2O3 fiber with NH3 followed by stress graphitization at approx. 2000 deg C. Such fibers displayed values comparable to PAN based carbon fibers but the mechanicals were variable most likely because of redeposition of volatiles at 2000 deg C. In addition, the cost of the fibers was very high due to the need for many hours of nitriding necessary to convert the BsO3 fibers. the use of batch nitriding negated two possible cost advantages of this concept, namely, the ease of drawing very fine, multi-filament yarn of B2O3 and more importantly the very low cost of the starting materials.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1994
- Accession Number
- ADA274693
Entities
People
- J. Economy