Accession Number : ADA302655

Title :   Behavior of Composite Bolted Joints at Elevated Temperature.

Descriptive Note : Contract rept.,

Corporate Author : DELAWARE UNIV NEWARK CENTER FOR COMPOSITE MATERIALS

Personal Author(s) : Wilson, Dale W. ; Pipes, R. B.

PDF Url : ADA302655

Report Date : SEP 1979

Pagination or Media Count : 107

Abstract : Experimental results from an investigation which examines the combined effects of temperature, joint geometry and out-of-plane constraint upon the response of mechanically fastened composite joints are presented. Data are presented for simulated mechanically fastened joint conditions in two laminate configurations (0/+/-45/902s and 45/0/-45/02/-45/0/45/02/90s) fabricated from Hercules AS/3501-6 graphite-epoxy. Strength and failure mode results are presented for the test temperatures of 21C (70F) 121C (250F) and 177C (350F) and for a range of the geometric parameters w/D and e/D from 3.71 to 7.43 and 1.85 to 3.69, respectively. A hole diameter, D of 5.16 mm (0.203 in.) was utilized for all tests. Pin bearing tests with out-of-plane constraint were conducted at room temperature only. All elevated temperature data were generated for pin bearing conditions. Three replicates of each test coupon geometry and laminate configuration were tested at each of three temperatures - totalling 126 tests in all. Ultrasonic "C" scan inspection of the failed specimens was employed to assess the damage region and to determine failure mode. Comparative data are presented for pin bearing and out-of-plane constraint conditions for the above mentioned joint configurations. The joint under pin loading was modeled by two-dimensional finite-element methods. Predicted net section strain concentrations were compared with experimental results. (AN)

Descriptors :   *LAMINATES, *GRAPHITE EPOXY COMPOSITES, *BOLTED JOINTS, STRESS STRAIN RELATIONS, MATHEMATICAL MODELS, NONDESTRUCTIVE TESTING, STRESS ANALYSIS, HIGH TEMPERATURE, FINITE ELEMENT ANALYSIS, LOADS(FORCES), COMPARISON, DEFORMATION, SHEAR MODULUS, DAMAGE ASSESSMENT, COMPOSITE STRUCTURES, MATRIX MATERIALS, BEARING STRENGTH, STRENGTH(MECHANICS), SHEAR STRESSES, TENSION, MOISTURE, FAILURE(MECHANICS), FASTENINGS, THERMAL CYCLING TESTS, THERMAL DEGRADATION, ULTRASONIC TESTS, STRESS CONCENTRATION.

Subject Categories : Laminates and Composite Materials
      Couplers, Fasteners, and Joints
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE