Amorphization mitigation in boron-rich boron carbides quantified by raman spectroscopy

Abstract

Boron carbide is an extremely hard and lightweight material used in armor systems. Upon impact above the Hugoniot elastic limit (HEL), boron carbide loses strength and suddenly fails. Atomistic models suggest that boron-rich boron carbides could mitigate amorphization. Such samples were processed, and indentation-induced amorphous zones were created throughout the boron-rich samples of varying degrees and were mapped with Raman spectroscopy to assess changes in the amorphization intensity. Boron-rich samples with a B/C ratio of 6.3 showed a large reduction in amorphization intensity compared to commonly used stoichiometric B4 C, in agreement with recent TEM results. Additionally, hardness trends were also noted as boron content is varied. This offers another pathway in which doping boron carbide can reduce amorphization.