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.

Thermal treatments of steel components with the goal of hardening often result in distortion by releasing the residual stresses which were brought into the specimen during the preceding processing steps. The goal of the presented work is the minimization of this distortion. By generating definite residual stress fields and investigating the resulting distortion, the distortion mechanism can be observed in detail. A flexible and reproducible way to generate such residual stress fields inside a specimen is by means of local thermal treatment with a laser beam. Computer simulations as well as experiments were carried out using an idealized tooth of a gearwheel (finger sample) as a model system. The deformation of the samples due to the laser heat treatment and the stress fields generated inside the samples were determined with respect to different process parameters.

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