Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2024 Sep 14;14(18):1493.
doi: 10.3390/nano14181493.

Toughening Mechanism in Nanotwinned Boron Carbide: A Molecular Dynamics Study

Hongchi Zhang  1 , Yesheng Zhong  1 , Xiaoliang Ma  1 , Lin Yang  1 , Xiaodong He  1   2 , Liping Shi  1
Affiliations

Toughening Mechanism in Nanotwinned Boron Carbide: A Molecular Dynamics Study

Hongchi Zhang et al. Nanomaterials (Basel). .

Abstract

Boron carbide ceramics are potentially ideal candidates for lightweight bulletproof armor, but their use is currently limited by their low fracture toughness. Recent experimental results have shown that sintered samples with high twin densities exhibit high fracture toughness, but the toughening mechanism and associated crack propagation process of nanotwinned boron carbide at the atomic scale remain a mystery. Reported here are molecular dynamics simulations with a reactive force field potential to investigate how nanoscale twins affect the fracture toughness of boron carbide ceramics. The results show that the strength disparity on either side of a twin boundary is the fundamental reason for the toughening effect; the twin boundary impedes crack propagation only when the crack moves to a region of higher fracture strength. The fracture toughness of nanotwinned boron carbide is greatly affected by the angle between the twin boundary and the prefabricated crack. At an angle of 120°, the twin boundary provides the maximum toughening effect, enhancing the toughness by 32.72%. Moreover, phase boundaries-another common structure in boron carbide ceramics-have no toughening effect. This study provides new insights into the design of boron carbide ceramics with high fracture toughness.

Keywords: boron carbide ceramic; fracture toughness; molecular dynamics; phase boundary; twin boundary.

PubMed Disclaimer

Conflict of interest statement

Xiaodong He is working in Shenzhen STRONG Advanced Materials Research Institute Co., Ltd., and other authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Left: atomic structures of (a) twin boundary (TB) and (b) phase boundary (PB). Right: simulation models for fracture toughness of (c) nanotwinned (NT) B4C and (d) PB B4C.
Figure 2
Figure 2
Stress–strain relationships of single-crystal (SC) and NT B4C at several typical included angles.
Figure 3
Figure 3
Changes in von Mises stress distribution with crack propagation for NT (first row) and SC (second row) B4C models at angles of (a) 90°, (b) 40°, and (c) 140°.
Figure 4
Figure 4
Variation in fracture energy of NT and SC B4C with included angle.
Figure 5
Figure 5
Stress–strain relationship of SC-120 model and NT-120 model.
Figure 6
Figure 6
Stress–strain relationships of SC and PB B4C at several typical included angles.
Figure 7
Figure 7
Changes in von Mises stress distribution with crack propagation for PB (first row) and SC (second row) B4C models at angles of (a) 90°, (b) 40°, and (c) 140°.
Figure 8
Figure 8
Variation in fracture energy of PB and SC B4C with included angle.
See this image and copyright information in PMC

References

    1. Gogotsi G., Groushevsky Y.L., Dashevskaya O., Gogotsi Y.G., Lavrenko V. Complex investigation of hot-pressed boron carbide. J. Less Common Met. 1986;117:225–230. doi: 10.1016/0022-5088(86)90037-8. - DOI
    1. Thevenot F. Boron carbide—A comprehensive review. J. Eur. Ceram. Soc. 1990;6:205–225. doi: 10.1016/0955-2219(90)90048-K. - DOI
    1. Vogler T., Reinhart W., Chhabildas L.C. Dynamic behavior of boron carbide. J. Appl. Phys. 2004;95:4173–4183. doi: 10.1063/1.1686902. - DOI
    1. Savio S., Rao A.S., Reddy P.R.S., Madhu V. Microstructure and ballistic performance of hot pressed & reaction bonded boron carbides against an armour piercing projectile. Adv. Appl. Ceram. 2019;118:264–273.
    1. Le Godec Y., Courac A., Solozhenko V.L. High-pressure synthesis of superhard and ultrahard materials. J. Appl. Phys. 2019;126:151102. doi: 10.1063/1.5111321. - DOI

LinkOut - more resources