Initiation and propagation of delamination in a centrally notched composite laminate

Journal Article · Fri Jan 01 00:00:00 EST 1993 · Journal of Composite Materials; (United States)

DOI:https://doi.org/10.1177/002199839302700303· OSTI ID:6300336

Jen, M H.R.; Kau, Y S; Hsu, J M ^[1]

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1. National Sun Yat-Sen Univ., Kaohsiung (Taiwan, Province of China)

A prediction model based on boundary layer theory is proposed to obtain interlaminar stress distributions and singularities at the free edge around the hole in a composite laminate. The Hashin-Rotem failure criterion is used to predict the loading and location at which initiation of delamination occurred. The model has been validated by a series of experiments for static tension and T-T fatigue tests. The test specimens include both the orthotropic and quasi-isotropic laminates. A circular hole was drilled in the center of each specimen. X-ray radiography was used to examine damage mode, location of the onset of delamination and propagation at each loading step. An approximately linear relationship is found between delamination area and stiffness reduction for the centrally notched quasi-isotropic laminates. The residual strength of the laminate first increases as applied cycles increased and then decreases during fatigue tests. Residual stiffness always decreases monotonically with the increase of applied cycles. 19 refs.

• OSTI ID: 6300336
• Journal Information: Journal of Composite Materials; (United States), Vol. 27:3; ISSN 0021-9983
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
CRACK PROPAGATION
OPENINGS
DYNAMIC LOADS
FATIGUE
NOTCHES
MATERIALS
MECHANICAL PROPERTIES
360603* - Materials- Properties