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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Atomic structure and structural stability of Sc75Fe25 nanoglasses
1Institute for Nanotechnology, Karlsruhe Institute of Technology (KIT), Karlsruhe 76021, Germany. jxfang@mail.xjtu.edu.cn
Nano Letters
|November 30, 2011
Summary
Nanoglasses, solids with nanoscale glassy regions, show increased interfacial regions with higher annealing temperatures. This nanostructure enhances ductility in Sc(75)Fe(25) glasses, offering a path to more ductile materials.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Nanoglasses are characterized by nanometer-sized glassy regions interconnected by lower-density interfaces.
- Understanding the structure-property relationship in nanoglasses is crucial for developing advanced materials.
Purpose of the Study:
- To investigate the structural evolution of Sc(75)Fe(25) nanoglasses under thermal annealing.
- To correlate microstructural changes with mechanical properties, specifically ductility.
Main Methods:
- Electron microscopy, positron annihilation spectroscopy, and small-/wide-angle X-ray scattering were employed to characterize nanoglass structure.
- In situ small-angle X-ray scattering monitored structural changes during annealing.
- Micro-compression tests evaluated the deformation behavior of nanoglass and ribbon glass.
Main Results:
- Positron annihilation spectroscopy revealed nanoglasses composed of 65% glassy and 35% interfacial regions.
- Annealing increased the width and volume fraction of interfacial regions exponentially.
- Correlation length, related to interfacial region size, increased from 1.3 to 1.7 nm with temperature elevation.
- Nanoglasses exhibited remarkable plasticity, unlike brittle ribbon glass, due to glass-glass interfaces.
Conclusions:
- Thermal annealing significantly modifies the interfacial structure of nanoglasses.
- The nanostructure, particularly the interfaces, is key to achieving high ductility in glasses.
- Nanoglasses present a promising route for engineering ductile glass materials.
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