Optoacoustic Investigations of Mechanical Properties of Ultrafine-grained Aluminum AD1 after Severe Plastic Deformation by Torsion and Thermal Treatment

摘要

The results of investigations of mechanical properties of metals before and after severe plastic deformation and thermal treatment of commercial aluminum AD1 are presented in this paper. The use of optoacoustic technique allowed to measure values of propagation speed of longitudinal elastic waves in a plate and in a thin rod for various regimes of processing and to show the correlation of speed and pulse attenuation with a change of material microstructure. The sound velocity is determined by predominant crystallographic direction of face-centered cubic lattice of aluminum, and attenuation of acoustic pulse is determined by presence and distribution of defects in material structure.