NFLUENCE OF NANOSTRUCTURATION ON THE SOUND VELOCITY IN ALUMINUM AL_99.50

The paper aims to determine the influence of nanostructure on sound velocity, to severe plastic deformation by cold multiaxial forging of aluminum. The deformation process is discontinuous and comprises deformation processes defining a severe plastic deformation cycle. Thus, a number of 7 determinations were performed for each sample, corresponding to the first 12 cycles of severe plastic deformation. As a result of the analysis of the results, it can be deduced that the area of passages 3, 4 and 5 represents, in fact, precisely the transition zone between micrometric granulation and mesoscopic (ultrafine) granulation, which is only