Accession Number : ADA113654

Title :   Research Study to Define the Critical Failure Mechanisms in Notched Composites under Compression Fatigue Loading.

Descriptive Note : Final rept. Sep 79-Mar 81,


Personal Author(s) : Rosen,B W ; Nagarkar,A P ; Pipes,R B ; Walsh,R

PDF Url : ADA113654

Report Date : Mar 1981

Pagination or Media Count : 105

Abstract : Analytical and experimental studies of identify the dominant failure mechanisms for compression fatigue of notched composite laminates have been conducted. The effects of stacking sequence and matrix material on damage growth as well as failure mechanisms under compression fatigue loading are reported. Two types of resin materials and four kinds of laminate layups have been considered. Two of the stacking sequences are fiber dominated and two are quasi-isotropic. Ultrasonic C-scans and photomicrographic studies have been utilized for experimental observations. An analytical methodology developed for the study of tension fatigue of notched laminates has been modified to obtain patterns of damage growth under quasi-static load by increasing it gradually in steps. For each step increase in load, a finite element stress analysis is performed and intralaminar and/or interlaminar failures in the elements are predicted.

Descriptors :   *Composite materials, *Matrix materials, *Notch toughness, *Failure(Mechanics), Loads(Forces), Stacking, Fatigue(Mechanics), Tensile strength, Stress analysis, Finite element analysis, Analytical chemistry, Laminates, Epoxy resins, Graphite, Laboratory tests, Photomicrography

Subject Categories : Physical Chemistry
      Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE