Accession Number : ADA307602

Title :   Novel Approaches for Alleviation of Electrical Hazards of Graphite-Fiber Composites,

Corporate Author : JET PROPULSION LAB PASADENA CA

Personal Author(s) : Ramohalli, Kumar

PDF Url : ADA307602

Report Date : 15 OCT 1979

Pagination or Media Count : 50

Abstract : This study was aimed at exploring the feasibility of different approaches to solve the electrical problems posed by graphite-fiber composites. Four basically different approaches were considered: gasification of fibers, retention in the matrix, clumping to prevent entrainment, and electrical insulation of fibers. The techniques used to achieve them are described in some detail. Those involved surface treatment of fibers to improve the wettability of fibers and coating the fibers with the selected substances before laying them up for composite fabrication. Thermogravimetric analyses were performed on the plain and treated fibers in inert (nitrogen, argon) and reactive (air) atmospheres. The treated fibers embedded in epoxy were ignited in a Bunsen flame to determine the efficiency of these treatments. A simple apparatus was assembled to detect the time for the first short circuit (in a typical electrical circuit) when exposed to the combustion products from a graphite fiber composite fire. The state-of-the-art and treated fibers cast in typical epoxy were burned and ranked for potential success. It was inferred that the gasification schemes appear promising when reduction or oxidation is tried. It was also found that some very promising candidates were available for the clumping and for the electrical insulation of fibers. The description of a plan for future work in this area concludes this report.

Descriptors :   *HAZARDS, *FIBER REINFORCED COMPOSITES, *ELECTRICAL PROPERTIES, *GRAPHITED MATERIALS, COMPOSITE MATERIALS, SURFACE FINISHING, CARBON FIBERS, NITROGEN, GASES, COATINGS, WETTING, OXIDATION, ENERGY CONVERSION, FIRES, CIRCUITS, SHORT CIRCUITS, ARGON, ELECTRICAL INSULATION, COMBUSTION PRODUCTS, THERMOGRAVIMETRIC ANALYSIS.

Subject Categories : Laminates and Composite Materials
      Inorganic Chemistry
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE