Federal Institute of Materials Research and Testing (BAM)

Abstract：

In search for a structural understanding of aging of metallic glasses, we exploit here the ability to track atomic-scale dynamics via x-ray photon correlation spectroscopy (XPCS). Conducted across temperatures and under the application of stress, the results reveal non-monotonically evolving and fluctuating relaxation times throughout isothermal conditions, demonstrating heterogeneous dynamics at the atomic scale. In concert with atomistic simulations, we identify possible mechanisms of correlated atomic-scale dynamics that can underly the temporal fluctuations and structural decorrelations (Acta Materialia 267 (2024) 119730). Furthermore, a transition from classical stretched exponential to power-law decorrelations emerges at sufficiently long waiting times, which we interpret as a signature of anomalous transport (Nature Communications 15 (2024) 6595). We discuss these findings in the context of an emerging microstructure in metallic glasses.

Brief CV of Prof. Robert Maaß:

Robert Maaß is an accomplished materials scientist with a distinguished academic and professional background. He currently serves as the head of the materials engineering department at the Federal Institute of Materials Research and Testing (BAM) in Berlin and an honorary professor at the Technical University of Munich. Previously, he was an assistant professor at the University of Illinois at Urbana-Champaign and a junior research group leader at Georg-August University of Göttingen. Maaß has also worked as a management consultant for McKinsey and Company and conducted postdoctoral research at ETH Zürich and the California Institute of Technology. His research focuses on microstructure-property relations in metals, and he has published extensively in this area. Maaß has received numerous awards, including the Masing Memorial Medal from the German Materials Society and the NSF CAREER Award, highlighting his significant contributions to materials science.

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主持人：孙永昊 副研究员

联系人：傅琦（82649469）