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Updated: Sep 18, 2025
10:28
Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
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A new twinning mechanism induced by solute electronic structures
Wenjin Zheng1, Huasheng Lei1, Wei Lai1
1State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, Fujian 350002, P. R. China. yuzyemlab@fzu.edu.cn.
Materials Horizons
|June 20, 2025
Summary
Solute segregation, specifically tungsten (W) atoms, induces a new growth twinning mechanism in (V, W)C precipitates by altering local electronic structure. High W concentrations promote twinning, while lower concentrations suppress it.
Area of Science:
- Materials Science
- Crystallography
- Solid-State Chemistry
Background:
- Twin boundaries are crucial microstructural features in polycrystalline materials, impacting their stability and mechanical performance.
- Understanding the mechanisms of twin formation is essential for controlling material properties.
Purpose of the Study:
- To identify and characterize a novel solute segregation-induced growth twinning mechanism.
- To elucidate the role of local electronic structure and solute concentration in twin formation.
- To provide insights for controlling twinning in crystalline materials.
Main Methods:
- Aberration-corrected scanning transmission electron microscopy (STEM) for high-resolution imaging.
- Energy-dispersive spectroscopy (EDS) for elemental analysis.
- First-principles calculations to investigate electronic structure and coordination changes.
Main Results:
- Interfacial segregation of tungsten (W) atoms was observed to trigger growth twinning in (V, W)C precipitates.
- Twin boundary formation is highly dependent on W concentration: high concentrations (~50 at%) promote twinning, while lower concentrations (~20 at%) suppress it.
- First-principles calculations revealed a coordination shift from octahedral (VC) to trigonal (W2C) geometry with increasing W concentration, driving the twinning mechanism.
Conclusions:
- A new solute-induced growth twinning mechanism driven by local electronic structure changes has been identified.
- Precise control over solute segregation and concentration is key to manipulating twinning events in materials.
- This study offers a pathway for tailoring material properties through controlled twin formation.
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