Abstract
Variation in the rate of ultrasonic wave propagation in tensile polycrystalline materials has been observed and examined. The regular features exhibited by these phenomena are found to be related to the multiple-stage behaviour of plastic flow curves and to plastic flow localization. It is shown that the observed strain and acting-stress dependences of ultrasonic rate are universal in character and thus typical of a number of metals and alloys. An interpretation of the observed effects is proposed; the role of these effects in the emergence of macroscopic inhomogeneities of plastic flow is considered.
