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Updated: Mar 13, 2026
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Negative Additive Manufacturing of Complex Shaped Boron Carbides
Published on: September 18, 2018
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Breaking the icosahedra in boron carbide
Kelvin Y Xie1, Qi An2, Takanori Sato3
1Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218.
Summary
Laser-assisted atom probe tomography reveals boron carbide icosahedra are less stable than expected, challenging previous assumptions about their structural integrity and amorphization. This study offers new insights into crystalline material stability.
Area of Science:
- Materials Science
- Nanotechnology
- Solid-State Physics
Background:
- Boron carbide is known for its exceptional structural stability.
- Understanding the atomic-level bonding and structure is crucial for predicting material behavior.
Purpose of the Study:
- To characterize the atomic structure and interatomic bonding in boron carbide using advanced techniques.
- To investigate the stability of icosahedral structures within boron carbide under experimental conditions.
Main Methods:
- Laser-assisted atom probe tomography (LA-APT) was employed to analyze boron carbide.
- Individual ionization events were characterized to understand atomic bond strengths.
- Quantum mechanics simulations were integrated with experimental data.
Main Results:
- Crystallographic planes were identified, indicating crystallinity is maintained during field evaporation.
- Unexpected evidence of individual icosahedra destruction was observed.
- Statistical analysis revealed that boron carbide icosahedra are not as stable as previously assumed.
Conclusions:
- The study provides critical insights into the structural instability and amorphization mechanisms of boron carbide.
- Atom probe tomography is a powerful tool for analyzing the stability and interactions of building blocks in complex crystalline materials.
Keywords:
ab initio molecular dynamicsbond dissociationlaser-assisted atom probe tomographymultiple hitsMore Related Videos
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