Journal Published Online: 01 January 2002
Volume 24, Issue 1

Comparison of the ±45° Tensile and Iosipescu Shear Tests for Woven Fabric Composite Materials

CODEN: JCTRER

Abstract

The mechanical response of a woven eight-harness satin graphite/polyimide composite has been investigated by performing ±45° tensile and Iosipescu shear tests at room temperature. Nonlinear finite element simulations of the tests have been conducted to determine internal stress distributions in the ±45° tensile and Iosipescu fabric specimens as a function of load. In the experimental part of this study, a series of tensile and Iosipescu shear tests have been performed. Acoustic emission techniques have been employed to monitor damage initiation and progression in the composite. The finite element computations have shown that the internal stress distributions in the Iosipescu and tensile fabric specimens are significantly different. In the gage sections of Iosipescu specimens, the state of stress is essentially pure shear, whereas the tensile tests generate biaxial stress conditions. It has been shown in this research that the shear strength of the composite determined from the maximum loads obtained from the Iosipescu shear tests is significantly higher than the shear strength obtained from the ±45° tensile tests. Moreover, the initiation of intralaminar damage in the tensile specimens occurs at much lower loads than in the Iosipescu specimens. It appears that the ±45° tensile test significantly underestimates the shear strength of the composite evaluated from the onset of intralaminar damage and the maximum loads.

Author Information

Kumosa, M
University of Denver, Denver, CO
Odegard, G
University of Denver, Denver, CO
Armentrout, D
University of Denver, Denver, CO
Kumosa, L
University of Denver, Denver, CO
Searles, K
Oregon Graduate Institute of Science and Technology, Portland, OR
Sutter, JK
NASA Glenn Research Center at Lewis Field, Cleveland, OH
Pages: 14
Price: $25.00
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Stock #: CTR10892J
ISSN: 0884-6804
DOI: 10.1520/CTR10892J