Accession Number : ADA302442

Title :   Experimental Studies of Graphite-Epoxy and Boron-Epoxy Angle Ply Laminates in Shear,

Corporate Author : TECHNION - ISRAEL INST OF TECH HAIFA

Personal Author(s) : Weller, T.

PDF Url : ADA302442

Report Date : SEP 1977

Pagination or Media Count : 92

Abstract : This report describes and presents a test program carried out at NASA Langley Research Center aimed at defining the nonlinear/inelastic response under inplane shear of a large variety of 3M SP-286T3 Graphite-Epoxy and AVCO 5505/5.6 Mil. Dia. Boron-Epoxy angle-ply laminates, as well as obtaining their strength allowables and detecting the mechanisms which govern their mode of failure. Two types of specimens for the program were chosen, tested and evaluated: shear panels stabilized by an Aluminum Honeycomb core and shear tubes. A modified biaxially compression/tension loaded picture frame' was designed and utilized in the test program with the shear panels. Evaluation of the experimental results, i.e. the type of experienced stress-strain field and strength values observed for the panels tested with this new apparatus, and comparison of the results with those experienced by the tubes, indicate that the new modified picture-frame has fulfilled and justified the expectations and proved to be an adequate and reliable device for inplane shear testing. The results obtained with this test technique categorically prefer the shear panels, rather than the tubes, for adequate and satisfactory experimental definition of the objectives concerned with the present test program. The present test results indicate the existence of a so-called core-effect which ought to be considered when reducing experimental data for weak in shear laminates.

Descriptors :   *LAMINATES, *SHEAR STRESSES, *EPOXY COMPOSITES, *BORON, *GRAPHITE EPOXY COMPOSITES, COMPRESSION, SHEAR PROPERTIES, STRESS STRAIN RELATIONS, STRENGTH(MECHANICS), ALUMINUM, TENSION, FRAMES, FAILURE(MECHANICS), EPOXY RESINS, HONEYCOMB CORES, SHEAR TESTS.

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE