Use of acoustic emission for defect detection in adhesively bonded cylindrical joints loaded in torsion

The Acoustic Emission (AE) technique has been applied in order to detect and recognise the presence and size of defects in cylindrical adhesively bonded joints loaded in torsion. The application of a Design of Experiment procedure showed that load rate and curing time mainly affect the resistance of the joint. Statistical correlation coefficients confirm this result. Acoustic Emission also are more correlated to load rate and curing time than to defect size. In the tests performed at strictly constant load rate and curing time, a very good correlation between defect size and Acoustic Emission parameters (counts, events and amplitude distributions) has been found. In conclusion a test procedure for defect detection in adhesively bonded joints, based on Acoustic Emission application, is proposed.