Possibility of a soliton description of acoustic emission during plastic deformation of crystals

Abstract

Two basic sources of acoustic emission (AE) during plastic deformation of pure crystals are discussed. One is related to nonstationary dislocation motion (the bremsstrahlung type of acoustic radiation), and the other to dislocation annihilation processes (the main component of the transition type of acoustic radiation). The possible soliton description of the bremsstrahlung acoustic radiation by oscillating dislocation kink and by a bound kink-antikink pair (dislocation breather) is considered on the basis of Eshelby’s theory [Proc. Roy. Soc. London A 266, 222 (1962)]. The dislocation annihilation component of the transition acoustic emission is considered only in relation to the Frank–Read source operation. A soliton model for this type of acoustic radiation is proposed and the simple quantum-mechanical hypothesis is advanced for the purpose. Both soliton descriptions are discussed on the basis of available experimental data on the AE intensity behavior during tensile deformation of crystals.