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Updated: Jun 25, 2026
06:45
Negative Additive Manufacturing of Complex Shaped Boron Carbides
Published on: September 18, 2018
Depressurization amorphization of single-crystal boron carbide
1WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
Physical Review Letters
|March 5, 2009
Summary
Single-crystal boron carbide (B4C) amorphizes upon depressurization due to nonhydrostatic stresses. This phenomenon involves irreversible bending of atomic chains within the material
Area of Science:
- Materials Science
- Solid-State Physics
- Chemistry
Background:
- Boron carbide (B4C) is a well-known ceramic material with exceptional hardness and high melting point.
- Understanding the phase transitions of B4C under extreme conditions is crucial for its applications.
Purpose of the Study:
- To investigate the phenomenon of depressurization amorphization in single-crystal boron carbide.
- To elucidate the role of nonhydrostatic stresses in the high-pressure phase transitions of B4C.
Main Methods:
- In situ high-pressure Raman spectroscopy was employed to monitor B4C during pressure changes.
- First-principles molecular dynamics simulations were utilized to understand the atomic-level mechanisms.
Main Results:
- Localized amorphization of B4C was observed during the unloading process from high pressures.
- Nonhydrostatic stresses were identified as a critical factor influencing the high-pressure phase transition.
- Simulations revealed that pressure-induced irreversible bending of C-B-C atomic chains causes amorphization.
Conclusions:
- Depressurization amorphization is a significant phenomenon in single-crystal boron carbide.
- The study highlights the critical role of stress states in the structural stability of B4C.
- Understanding these mechanisms provides insights into the mechanical behavior of ceramics under extreme conditions.
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