High pressure Raman spectroscopy of boron-rich boron carbides up to 50 GPa

Journal Article · 06 January 2025 · High Pressure Research

DOI: https://doi.org/10.1080/08957959.2024.2449365 · OSTI ID:2496637

Sereika, Raimundas ^[1]; Iwan, Seth ^[2]; Baker, Paul A. ^[2]; Vohra, Yogesh K. ^[2]

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1. University of Alabama at Birmingham, AL (United States); University of Alabama at Birmingham
2. University of Alabama at Birmingham, AL (United States)

We investigated the effects of increased boron content on the resistance to non-hydrostatic stress-induced (NHSI) local amorphous zones in boron-rich boron carbide (BxC) compounds. Using high-pressure Raman spectroscopy, we subjected B_4.3C, B_6.4C, and B_10.4C to pressures up to 50 GPa and monitored their responses. Our results show that higher boron content delays the onset of NHSI local amorphous zone formation, shifting it from 35 GPa in B_4.3C to approximately 50 GPa in B_10.4C. This enhanced resistance is attributed to a reduction in the formation of the B₁₂(CCC) polytype, which is susceptible to amorphization, and the greater flexibility of B–B–B chains. Furthermore, alternative mechanisms, such as boron vacancy-driven C–C bond formation, provide additional insights into defect-mediated structural changes that may influence the amorphization process. In conclusion, these findings highlight the dual role of boron content and defect mechanisms in improving the structural stability of B_xC materials under extreme environments.

• Research Organization: University of Alabama at Birmingham, AL (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: NA0004090
• OSTI ID: 2496637
• Journal Information: High Pressure Research, Journal Name: High Pressure Research Journal Issue: 1 Vol. 45; ISSN 0895-7959
• Publisher: Taylor & FrancisCopyright Statement
• Country of Publication: United States
• Language: English