Boron-based composite energetic materials (B-CEMs): Preparation, combustion and applications

Metal fuels are attractive for solid/hybrid rocket propulsion and energy-conversion applications, because of their high energy densities. Boron powder (B), due to its high gravimetric (58.30 MJ & BULL;kg(-1)) and volumetric heats of combustion (136.44 kJ & BULL;cm(-3)), is ideally one of the most promising fuel candidates for fuel-rich solid propellant (SP). However, from an application perspective, amorphous B has drawbacks of high ignition temperatures and incomplete combustion, resulting in low energy-release rate and efficiency. Thus, there is growing interest in employing B-based composite energetic materials (B-CEMs) in SP, explosives, and pyrotechnics. The present work provides a comprehensive review of the advances made over the past few decades in the areas of preparation, combustion, and applications of B-CEMs. The preparation methods of various types of B-CEMs are introduced, and the physicochemical properties of B-CEMs are systematically discussed particularly with regards to achieving advantages over B and other metal powders in a broad range of applications. The ignition and combustion behavior of different energetic formulations with B-CEMs are reviewed. Finally, the existing problems and future challenges in our understanding of the field (prospects) are discussed.

Automated summary

Metal fuels with high energy densities are attractive for solid/hybrid rocket propulsion and energy-conversion applications. Boron powder is an ideal fuel candidate due to its high gravimetric and volumetric heats of combustion. However, amorphous boron has drawbacks of high ignition temperatures and incomplete combustion. Thus, there is growing interest in using boron-based composite energetic materials. This review provides a comprehensive overview of the preparation, combustion, and applications of boron-based composite energetic materials, and discusses the future challenges in the field.