NDE of Adhesively Bonded Joints Using Acousto-Ultrasonics and Pattern Recognition
Adhesively bonded joints are increasingly being employed in structural as well as non-structural applications due to the advantages they offer in terms of design flexibility, stress distribution, strength-to-weight ratio and cost effectiveness. However, a major limitation in the structural use of adhesives, particularly in aerospace applications, is associated with the difficulty encountered in making an accurate measure of bond quality or potential performance after the joint has been assembled. Furthermore, the performance of bonded joints during service may be affected by environmental conditions or by service induced damage that would result in a requirement for verification of bond quality. There is consequently a need for nondestructive evaluation techniques that can provide assurance of the structural performance of bonded joints both after fabrication as well as during service life.
KeywordsAcoustic Emission Recognition Rate Stress Wave Failure Load Canonical Variable
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