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Rate-dependent mode I interlaminar crack growth mechanisms in graphite/epoxy and graphite/PEEKIn this paper the mode I fracture behavior of graphite/epoxy and graphite/PEEK composites is examined over four decades of crosshead rates (0.25-250 mm/min). Straight-sided double-cantilever-beam specimens consisting of unidirectional laminates were tested at room temperature. For graphite/epoxy the load-deflection response was linear to fracture, and stable slow crack growth initiating at the highest load level was observed for all rates tested. In contrast, mode I crack growth in the graphite/PEEK material was often unstable and showed stick-slip behavior. Subcritical crack growth occurring prior to the onset of fracture was observed at intermediate displacement rates. A mechanism for the fracture behavior of the graphite/PEEK material (based on viscoelastic, plastic, and microcrack coalescence in the process zone) is proposed and related to the observed rate-dependent phenomena.
Document ID
Document Type
Reprint (Version printed in journal)
Gillespie, J. W., Jr.
(Delaware Univ. Newark, DE, United States)
Carlsson, L. A.
(Delaware Univ. Newark, DE, United States)
Smiley, A. J.
(Delaware, University Newark, United States)
Date Acquired
August 13, 2013
Publication Date
January 1, 1987
Publication Information
Publication: Composites Science and Technology
Volume: 28
Issue: 1 19
ISSN: 0266-3538
Subject Category
Composite Materials
Accession Number
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