We propose a model for predicting the depletion zone arising next to grain boundaries during non-equilibrium segregation. The model directly links to distribution of segregation energies as provided by atomistic simulations. We expose the theoretical framework based on the thermodynamic extremal principle and propose an efficient algorithm to solve the underlying equations. The example of the W-25at%Re is discussed to illustrate the main features of the model. Multi-component segregation kinetics is discussed for segregation of B, C, and N in Mo to illustrate site-competition scenarios. Comparison with earlier results obtained without depletion illustrates the importance of this effects. Finally the depletion zones along GBs are investigated for many different compositions to asses for which material composition and heat treatments they may be observed experimentally. We find that extended depletion zones arise for very small solute concentrations.
Bibliographische NotizFunding Information:
Financial support by the Austrian Federal government (in particular from the Bundesministerium für Verkehr, Innovation and Technologie and the Bundesministerium für Wirtschaft und Arbeit) and the Styrian Provincial Government, represented by Österreichische Forschungsförderungsgesellschaft mbH and by Steirische Wirtschaftsförderungsgesellschaft mbH, within the research activities of the K2 Competence Centre on “Integrated Research in Materials, Processing and Product Engineering”, operated by the Materials Center Leoben Forschung GmbH in the framework of the Austrian COMET Competence Centre Programme, Projects A1.23 is gratefully acknowledged. J.S. gratefully acknowledges the financial support by the Czech Science Foundation in the frame of the Project 17-01641S .
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