Acoustic Emission During Deformation of High-Purity Aluminum Single Crystals.

Single crystal aluminum specimens with the purity of 99. 9997% are studied for their acoustic emission (AE) in the process of tension at a constant rate of 3. 10** minus **3 s** minus 1. Three cases of the tension axis orientation are investigated: in the middle of the steriographic triangle and near to the directions of left bracket 110 right bracket and left bracket 100 right bracket . Registration of the AE was performed simultaneously by two types of pickups: the resonance one (with basic frequency 200 kHz) and the bandwidth one (with the band of 0. 1. . . 3 MHz). In all the above cases dependences of the AE count rate N on deformation epsilon and the total count of AE N on the stress tau are obtained. Peculiarities of the acoustic diagram N( epsilon ) are compared with the pattern of the development of slip traces detected by the metallographic method. The given results are compared with the data available from literature concerning single crystals of aluminum with those obtained when studying AE on polycrystalline aluminum of the same purity.