Atomic mobility in nanoglasses

• Applicants: Professor Dr.-Ing. Horst Hahn; Professor Dr.-Ing. Gerhard Wilde
• Subject Area: Thermodynamics and Kinetics as well as Properties of Phases and Microstructure of Materials ; Metallurgical, Thermal and Thermomechanical Treatment of Materials
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 427131164

• Final Report Year: 2025

Final Report Abstract

Nanoglasses are a relatively new class of amorphous materials, consisting of two distinct amorphous regions with different atomic arrangements with characteristic dimensions of a few nanometers. It has been found that the atomic structure of metallic nanoglasses is distinctly different from that of the well-known metallic glasses prepared by quenching from the melt. Compositional fluctuations (segregation), free volume differences and increased medium range order, but without crystallization, seem to be the major structural differences between the nanoglasses and the rapidly quenched metallic glasses. The structural differences in the two regions result in drastic changes of the mechanical and the functional properties compared to rapidly quenched metallic glasses. Diffusion can be used as a tool to identify structural differences in materials, for example, diffusion along interfaces and in the bulk are typically very different. In the current project, atomic mobility has been studied in nanoglasses and in therapidly quenched reference structure to identify more details of the drastic structural differences between nanoglasses and the conventionally prepared metallic glasses. Studies of diffusion processes require detailed knowledge of the atomic structure, and, consequently, structural characterization of the metallic nanoglasses has been performed to identify the micro-structure of the nanoglasses and the atomic structure of the interfacial regions.

Publications

• Direct View on Non‐Equilibrium Heterogeneous Dynamics in Glassy Nanorods. Advanced Functional Materials, 31(38).
  Spangenberg, Katharina; Hilke, Sven; Wilde, Gerhard & Peterlechner, Martin
  
• Phase selection rule of high‐entropy metallic glasses with different short‐to‐medium‐range orders. Rare Metals, 41(6), 2021-2027.
  Ying, Hui‐Qiang; Liu, Si‐Nan; Wu, Zhen‐Duo; Dong, Wei‐Xia; Ge, Jia‐Cheng; Hahn, Horst; Provenzano, Virgil; Wang, Xun‐Li & Lan, Si
  
• Enhanced specific heat of the Sc79Fe21 nanoglass compared to the Sc79Fe21 amorphous melt-spun ribbon in a temperature range of 150–300 K. Materials Letters, 349, 134706.
  Wang, Chaomin; Hu, Qiang; Luo, Jipeng; Yin, Nan; Shi, Quan; Gleiter, Herbert & Hahn, Horst
  
• Evidence for Glass–glass Interfaces in a Columnar Cu–Zr Nanoglass. Advanced Functional Materials, 33(44).
  Voigt, Hendrik; Rigoni, Aaron; Boltynjuk, Evgeniy; Chellali, Mohammed Reda; Tyler, Bonnie; Rösner, Harald; Divinski, Sergiy; Hahn, Horst & Wilde, Gerhard
  
• In situ TEM studies of relaxation dynamics and crystal nucleation in thin film nanoglasses. Materials Research Letters, 11(12), 1022-1030.
  Voigt, Hendrik; Rigoni, Aaron; Boltynjuk, Evgeniy; Rösner, Harald; Hahn, Horst & Wilde, Gerhard
  
• Nanoscale Confinement of Dip‐Pen Nanolithography Written Phospholipid Structures on CuZr Nanoglasses. Advanced Materials Interfaces, 11(2).
  Vasantham, Srivatsan K.; Boltynjuk, Evgeniy; Nandam, Sree Harsha; Berganza, Eguiarte Eider; Fuchs, Harald; Hahn, Horst & Hirtz, Michael
  
• Enhanced diffusion in thin-film Cu-Zr nanoglasses. Acta Materialia, 265, 119634.
  Aaron, Rigoni C.; Boltynjuk, Evgeniy; Voigt, Hendrik; Rösner, Harald; Tyler, Bonnie; Hahn, Horst; Divinski, Sergiy V. & Wilde, Gerhard