Acoustic emission in initiation and propagation of the crack in an aluminum alloy under the effect of a corrosive medium

Previously abstracted from original as item 9003-6.1-0187Y. Crack initiation and propagation in an Al--Zn--Mg alloy, V92, was investigated after hardening and aging (10 h at 140 deg C) using double cantilever beam specimens. A crack was grown from a notch under static loading in a 3% NaCl solution and in a solution containing 20 g/dm exp 3 K2Cr2O7 and 13.5 g/dm exp 3 HCL. It is found that the moment of crack initiation can be best determined by using an energy parameter of acoustic emission, such as mean amplitude, whereas the growth of a crack can be best monitored on the basis of AE activity. Graphs. 12 ref.--X-ref.(US).