Accession Number : ADA309271

Title :   Effects of Thermal and Environmental Exposure on the Mechanical Properties of Graphite/Polyimide Composites.

Descriptive Note : Technical note,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CEN TER

Personal Author(s) : Hanson, M. P. ; Serafini, T. T.

PDF Url : ADA309271

Report Date : DEC 1971

Pagination or Media Count : 17

Abstract : Composites were exposed in circulating and static air environments up to 589 K (600 deg F) for a maximum of 1000 hours. Composites of HT-S, HM-S, Thornel 50S, and Fortafil 5-Y fiber and a new addition type polyimide resin were laminated in a matched-die mold. Flexural strength, flexural modulus, and interlaminar shear strengths were determined at 297, 533, and 598 K (75 deg, 500 deg , and 600 deg F) after various durations of exposure. Composite and fiber weight loss characteristics were determined by isothermal gravimetric analysis in air. Properties of composites exposed and tested at the environment temperatures are compared with those determined under short-term exposure. A new short beam interlaminar shear fixture is described. Environmental effects of long-term (up to 1 year) ambient temperature exposure on the elevated temperature mechanical properties of graphite/polyimide composites are presented.

Descriptors :   *THERMAL PROPERTIES, *MECHANICAL PROPERTIES, *EXPOSURE(GENERAL), *ENVIRONMENTAL IMPACT, *GRAPHITED MATERIALS, *POLYIMIDE RESINS, TEMPERATURE, FIBERS, ENVIRONMENTS, AIR, COMPOSITE MATERIALS, HIGH TEMPERATURE, FLEXURAL STRENGTH, GRAVIMETRIC ANALYSIS, STATICS, CIRCULATION, WEIGHT REDUCTION, ISOTHERMS.

Subject Categories : Polymer Chemistry
      Laminates and Composite Materials
      Plastics
      Mechanics
      Thermodynamics
      Environmental Health and Safety

Distribution Statement : APPROVED FOR PUBLIC RELEASE