Related Experiment Video
Updated: Mar 3, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
9.0K
Thermal rejuvenation in metallic glasses
Junji Saida1, Rui Yamada1, Masato Wakeda2
1Frontier Research Institute for Interdisciplinary Sciences (FRIS), Tohoku University, Sendai, Japan.
Science and Technology of Advanced Materials
|May 2, 2017
Summary
Structural rejuvenation in metallic glasses was achieved through controlled annealing. This process alters their atomic structure, potentially improving mechanical properties by modifying the glassy state.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- Metallic glasses exhibit unique properties due to their amorphous atomic structure.
- Structural relaxation and rejuvenation are key phenomena influencing metallic glass properties.
- Understanding and controlling the glassy structure is crucial for material applications.
Purpose of the Study:
- To investigate structural rejuvenation in metallic glasses via thermal annealing.
- To identify key parameters controlling the rejuvenation process.
- To establish a framework for predicting and controlling rejuvenation.
Main Methods:
- Experimental investigation of various alloy compositions.
- Theoretical analysis of structural changes during annealing.
- Development of a rejuvenation map based on annealing temperature and cooling rate.
- Analysis of potential energy, density, and local atomic structure.
Main Results:
- Thermal rejuvenation increased potential energy, decreased density, and softened mechanical properties.
- A rejuvenation map was constructed using annealing temperature (Ta/Tg) and cooling rate (Vc/Vi).
- Annealing above 1.2Tg with appropriate cooling generates a new glassy structure (rejuvenation).
- Partial rejuvenation was observed at lower temperatures (Ta/Tg ~ 1.07) in specific alloys.
Conclusions:
- Structural rejuvenation in metallic glasses can be controlled by annealing temperature and cooling rate.
- The proposed rejuvenation map provides a tool for optimizing thermal treatments.
- Controlling the glassy structure through rejuvenation offers a novel approach to enhance mechanical properties.
Related Concept Videos
02:37Metallic Solids
21.1K
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
21.1K
01:17Theory of Metallic Conduction
1.9K
The conduction of free electrons inside a conductor is best described by quantum mechanics. However, a classical model makes predictions close to the results of quantum mechanics. It is called the theory of metallic conduction.
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
1.9K
02:32Bonding in Metals
54.5K
Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Drüde called the “Electron Sea Model”.
54.5K
02:51Metal-Ligand Bonds
25.0K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
25.0K
01:27Biasing of Metal-Semiconductor Junctions
720
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
720
01:26Residual Stresses
714
Residual stresses reside in a structure even after removing the original stress inducer. This phenomenon often arises from varied plastic deformations across different parts of a structure. Consider a rod stretched beyond its yield point. It will not regain its original length due to permanent deformation. Even after load removal, the rod does not entirely lose stress because of uneven plastic deformations, resulting in residual stresses. The computation of these stresses in structures is...
714