You are being redirected because this document is part of your ASTM Compass® subscription.
    This document is part of your ASTM Compass® subscription.


    Effect of Laminate Thickness and Specimen Configuration on the Fracture of Laminated Composites

    Published: 0

      Format Pages Price  
    PDF (564K) 19 $25   ADD TO CART
    Complete Source PDF (8.9M) 454 $65   ADD TO CART

    Cite this document

    X Add email address send
      .RIS For RefWorks, EndNote, ProCite, Reference Manager, Zoteo, and many others.   .DOCX For Microsoft Word


    The effect of laminate thickness on the fracture behavior of laminated graphite/epoxy (T300/5208) composites has been studied. The predominantly experimental research program included the study of the [0/±45/90]ns and [0/90]ns laminates with thicknesses of 8, 32, 64, 96, and 120 plies and the [0/±45]ns laminate with thickness of 6, 30, 60, 90, and 120 plies. The research concentrated on the measurement of fracture toughness utilizing the center-cracked tension, compact tension, and three-point bend specimens. The development of crack-tip damage prior to fracture was also studied.

    Test results showed fracture toughness to be a function of laminate thickness. The fracture toughness of the [0/±45/90]ns and [0/90]ns centercracked laminates decreased with increasing thickness and asymptotically approached lower bound values of 1043 MPa √mm (30 ksi √in.) and 869 MPa √mm (25 ksi √in.), respectively. The fracture toughness of the [0/±45]ns center-cracked laminate increased with increasing thickness but reached an upper plateau value of 1390 MPa √mm (40 ksi √in.). The fracture toughness of all laminates was independent of crack size except the [0/90]2s laminate that split extensively. The fracture surface of all thick laminates was uniform in the interior and self-similar with the starter notch. With the exception of the [0/±45]ns laminate, the fracture toughness of the thicker laminates was relatively independent of specimen configuration.


    composite materials, graphite/epoxy, fracture toughness, thick laminate, center-cracked tension, compact tension, three-point bend

    Author Information:

    Harris, CE
    Assistant professor, Texas A&M University, College Station, TX

    Morris, DH
    Professor, Virginia Polytechnic Institute and State University, Blacksburg, VA

    Committee/Subcommittee: D30.04

    DOI: 10.1520/STP35348S