Temperaturabhängige Dynamic auf der Nanoskala und kritische Temperaturen von Gläsern mit unterschiedlicher Chemie durch Elektronen-Zeitkorrelations Mikroskopie

• Applicant: Professor Dr.-Ing. Gerhard Wilde, since 2/2023
• Subject Area: Thermodynamics and Kinetics as well as Properties of Phases and Microstructure of Materials ; Experimental Condensed Matter Physics
• Term: since 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 314661497

Electron time-correlation microscopy (etCM) will be applied to analyze the temperature dependence of the local mechanisms governing relaxation and diffusion in metallic glasses. Heterogeneities within the amorphous phases introduced by variation of the nominal composition or minor element additions, give rise e.g. to exceptional crystallization behavior and the related atomistic dynamics. In-situ dark-field (DF) time series under isothermal heating conditions sheds light on the relaxation and related diffusion at the given temperature. In particular, the following issues shall be addressed in this project: 1) relaxation and temporal-spatial dynamics of PdNiP and minor alloyed systems, 2) deduction of a critical temperature from the temperature dependence of the relaxation, 3) local analysis of heterogeneities, by variation of the chemical composition and deformation induced (PdNiP and AlYFe), and 4) methological aspects. It is to expect, that a critical temperature obtained by etCM and the temperature dependence of the dynamic domain size can be used to distinguish a glass from an amorphous solid in the microscope. It is also to expect, that the variation of chemistry might change the domain size at lower temperatures, becoming more uniform at higher temperatures and critical temperatures stay basically constant.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Martin Peterlechner, until 1/2023