Managing director, Testwell, Ltd., Daventry,
Pages: 11 Published: Jan 1988
Interlaminar shear failure caused by fatigue loading has been studied in carbonepoxy and glass-epoxy unidirectional composites. Short beam specimens were subjected to three-point bending loading with low mean stress, high mean stress, and zero mean stress at a range of alternating stresses to give lives in the range 104 to 107 cycles.
The indications of incipient failure given by acoustic emission were confirmed by ultrasonic Cscan and cutup. Of 150 specimens, only five failed to be confirmed by all three techniques.
After some initial trials to determine optimum gain levels and the addition of a voltage-controlled gate, acoustic emission proved simple to use, reliable, and accurate.
composites, fatigue, acoustic emission, interlaminar shear strength
Paper ID: STP26146S