Accession Number : ADA294724

Title :   Translaminar Fracture Toughness Test Methods and Results from Interlaboratory Tests of Carbon/Epoxy Laminates.

Descriptive Note : Final rept.,

Corporate Author : ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER WATERVLIET NY BENET LABS

Personal Author(s) : Underwood, John H. ; Kortschot, Mark T. ; Lloyd, W. R. ; Eidinoff, Harvey L. ; Wilson, Dale A.

PDF Url : ADA294724

Report Date : FEB 1995

Pagination or Media Count : 31

Abstract : Fracture tests were performed with carbon/polymer laminates and analyzed for the purpose of developing translaminar fracture toughness test and analysis procedures. Notched specimens were tested on two types of symmetrical layups, quasi-isotropic (0/45/90) and (0/90); two carbon fiber/epoxy materials, a relatively brittle T300 fiber/976 epoxy and a tougher AS4 fiber/977-2 epoxy; two laminate thicknesses, 2-mm and 4-mm; and three specimen configurations, the standard three-point bend and compact configurations, and an extended compact specimen with arm height-to-specimen width ratio of 1.9. Stress and displacement expressions were obtained for the extended compact specimen, including those for stress intensity factor, K, and crack-mouth opening displacement, V, in terms of relative notch length, a/W, and for a/W in terms of V. Relationships for the bending stresses that control self-similar and off-axis cracking for the extended compact specimen were also derived. (MM)

Descriptors :   *LAMINATES, *TOUGHNESS, *FRACTURE(MECHANICS), STRESS ANALYSIS, POLYMERS, LOADS(FORCES), CRACKING(FRACTURING), CRACKS, DAMAGE ASSESSMENT, DISPLACEMENT, FIBER REINFORCED COMPOSITES, BENDING, CARBON, BRITTLENESS, EPOXY COMPOSITES, ULTRASONIC TESTS, NOTCH TOUGHNESS.

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE