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P. Estermann, Y.V. Shan, E. Kozeschnik:
"Modelling grain boundary segregation in polycrystalline materials";
Talk: THERMEC 2021, Online; 2021-05-10 - 2021-05-14.

The segregation of solute atoms towards grain boundaries and dislocations can severely impact the mechanical properties of alloys. Interstitial atoms can move to the dislocation cores to reduce the system energy and thus increase the force necessary for movement. At the grain boundaries, segregations can influence the cohesion force between grains and eventually promote inter-granular fracture. Several models were devised to gain a better understanding of the mechanism and to be able to simulate the segregation kinetics over time. Recently, Svoboda et al. published a paper describing a set of equations for atom trapping based on the thermodynamic extremum principle. This model is implemented in the material simulation software MatCalc, where it can be used to analyze, for example, the influence of segregation on the grain boundary energy. This makes it possible to run parameter studies with varying inputs on several alloying systems. In addition, these results are compared to microprobe measurements taken from the literature, where good agreement is observed.

Project Head Ernst Kozeschnik:
K1 Met Thermomechanical modelling of continuous casting