Atomistic modelling of the Shape Memory Effect

Abstract

This paper reviews the status of molecular dynamics as a method in describing solid-solid phase transitions, and its relationship to continuum approaches. Simulation work done in NiTi and Zr using first principles and semi-empirical potentials is presented. This shows failures of extending equilibrium thermodynamics to the nanoscale, and the crucial importance of system-specific details to the dynamics of martensite formation. The inconsistency between experimental and theoretical crystal structures in NiTi is described, together with its possible resolution in terms of nanoscale effects.