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Postavalanche Relaxation Sheds Light on Twinning Mechanisms
Haile Gebrehiwet Seyoum1, Emil Bronstein1, Eilon Faran1
1Technion-Israel Institute of Technology, Faculty of Mechanical Engineering, Haifa 3200003, Israel.
Physical Review Letters
|June 23, 2025
Summary
Deformation twinning in magnesium involves distinct avalanche and relaxation events. Avalanches (twin nucleation) occur rapidly (μs), followed by slower relaxations (twin growth, ms), with nearly identical twinned volumes, revealing a geometric link.
Area of Science:
- Materials Science
- Physics
- Solid Mechanics
Background:
- Avalanches are abrupt transitions in complex systems, distinct from simpler relaxation dynamics.
- Deformation twinning involves microstructural changes crucial for material properties.
Purpose of the Study:
- To differentiate avalanche and relaxation dynamics during deformation twinning in magnesium.
- To investigate the relationship between twin nucleation and growth processes.
Main Methods:
- Analysis of deformation twinning in magnesium.
- Characterization of event timescales (μs for avalanches, ms for relaxations).
- Quantification of twinned volumes during nucleation and growth.
Main Results:
- Identified elemental differences in rate and duration between avalanches and relaxations.
- Observed that each avalanche is followed by a relaxation of nearly identical magnitude.
- Found that local volumes twinned during nucleation (avalanche) and growth (relaxation) are nearly identical.
Conclusions:
- Established a simple geometrical relationship between twin nucleation and subsequent twin growth.
- Elucidated fundamental mechanisms governing the early stages of twinning in magnesium.
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