Regensburg 2019 – wissenschaftliches Programm
MM 8.4: Vortrag
Montag, 1. April 2019, 16:45–17:00, H43
Atomistic Simulation of Dislocations in High Entropy Alloys — •Aviral Vaid1, Michael Zaiser2, and Erik Bitzek1 — 1Materials Science and Engineering, Institute I, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany — 2Institute of Materials Simulation, Department of Materials Science, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany
Understanding dislocation mobility and dislocation-obstacle interactions is of fundamental importance for the development of alloys with improved mechanical properties. Single phase high entropy alloys (HEAs) are a class of chemically complex alloys that have shown exceptional mechanical properties. Due to the chemical complexity of these alloys, the characteristics of energy landscape that a dislocation experiences in these alloys still needs to be investigated. Through atomistic simulations, we perform a comprehensive characterization of the segment-length-dependent dislocation properties such as Peierls barrier, Larkin length, dislocation line energy, and dislocation structure for both edge and screw dislocations. The dislocations are studied in model HEA systems using different potential formalisms to assess the robustness of the atomistic simulation results. The random nature of the pinning field, where in a sense every atom is a solute, leads to a complex situation as the dislocation adjusts its shape to the fluctuating energy landscape. The results are discussed in the context of parametrizing discrete dislocation dynamics models.