Precision structural and phase analysis of boron carbide

Abstract Structural analyses and phase quantification of solution-synthesised and commercially available boron carbide powders are conducted via Rietveld refinement of X-ray diffraction data. A fixed incidence parallel beam geometry is compared against the more commonly used Bragg-Brentano geometry. Fixed incidence parallel beam is found to have a significant advantage in phase quantification through the minimisation of peak aberrations due to the high X-ray transparency of boron carbide. The enhanced resolution and accuracy afforded by this technique allows for fundamental new insights into the phase content of boron carbide powders. Specifically, commercially obtained boron carbide powders are found to be multi-phasic, containing varying contents of both B∼4C and B∼6.5C phases. Solution-synthesised boron carbide produced in this study is found to comprise of B4.05C only. These findings have significant importance to the development of boron carbide for high-performance applications and present a potential avenue for the synthesis of high purity boron carbide powders with controlled stoichiometry.