Microscopic description of the kinetics of a martensitic transition in real crystals: bcc-hcp transition in Zr

The kinetics of the bcc-hcp transition in Zr in the presence of dislocations is investigated by numerical simulation methods. It is shown that the transition occurs in a nondiffusional (at a velocity of the order of the speed of sound) in two stages: relatively long development of instability of long-wavelength acoustic phonons and a fast stage of instability of short-wavelength phonons. The elastic stresses near a dislocation make it possible for these instabilities to develop at much lower temperatures than in an ideal crystal.