Accession Number : ADA305141

Title :   Elevated-Temperature Application of the IITRI Compression Test Fixture for Graphite/Polyimide Filamentary Composites.

Descriptive Note : Technical paper,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER

Personal Author(s) : Raju, B. B. ; Camarda, Charles J. ; Cooper, Paul A.

PDF Url : ADA305141

Report Date : SEP 1979

Pagination or Media Count : 48

Abstract : Seventy-nine graphite/polyimide compression specimens were tested to investigate experimentally the IITRI test method for determining compressive properties of composite materials at room and elevated temperatures (589 K (600 deg F)). Minor modifications were made to the standard IITRI fixture and a high degree of precision was maintained in specimen fabrication and load alignment. Specimens included four symmetric laminate orientations designated as 0, O,+ or - 45,90sub 2s, 90, and + OR - 45sub 5s. Specimens of various widths were tested to evaluate the effect of width on measured modulus and strength. In most cases three specimens of each width were tested at room and elevated temperature and a polynomial regression analysis was used to reduce the data. Scatter of replicate tests and back-to-back strain variations were low, and no specimens failed by instability. Variation of specimen width had a negligible effect on the measured ultimate strengths and initial moduli of the specimens. Measured compressive strength and stiffness values were sufficiently high for the material to be considered a usable structural material at temperatures as high as 589 K (600 deg F). (MM)

Descriptors :   *FIBER REINFORCED COMPOSITES, *COMPRESSIVE PROPERTIES, *GRAPHITE EPOXY COMPOSITES, SPACECRAFT, COMPOSITE MATERIALS, LAMINATES, STIFFNESS, ORIENTATION(DIRECTION), TEST METHODS, FABRICATION, STRAIN(MECHANICS), ALIGNMENT, REGRESSION ANALYSIS, FILAMENTS, FAILURE(MECHANICS), COMPRESSIVE STRENGTH, CONSTRUCTION MATERIALS, SUBSONIC FLIGHT, POLYIMIDE PLASTICS, POLYIMIDE RESINS.

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE