Including Thermal Activation in Simulation Calculations of Dislocation Glide

Our simulation method which was derived for athermal motion of flexible dislocations through obstacle arrays is extended to include thermally activated glide. The deterministic differential equations which describe the dynamics of dislocation motion get an additional stochastic term corresponding to thermal motion of atoms involved. Our approach is based on publications of Langevin, Fokker-Planck, and Klein-Kramers. The investigation of jerky glide reveals that there is an essential influence of the kinetic energy even in case of rather simple obstacle arrangements. Primary results of the simulations are waiting times at obstacles. Thus an activation analysis of our simulated data can be performed by Arrhenius plots in strict analogy to the procedure applied to experimental results.