Preparation, Ignition, and Combustion of Boron Fuels with CuO as an Additive

This paper aims to improve boron’s oxidation, ignition, and combustion by adding nano-CuO. Samples with different CuO mass ratios and sizes were prepared by milling. Their properties were investigated by the thermogravimetric analysis (TGA) technique, heated filament test, and particle combustion test in premixed air–C₂H₂ flame. In the TGA experiment at 5 K/min, increasing the ratio or reducing the size of CuO can promote the oxidation of boron powder. Among all CuO additives, 10 wt% nano-CuO can significantly reduce the onset oxidation temperature and improve the extent of the reaction of boron powder. In the heated filament test, CuO additives improve the boron to be ignited at a heating rate of 20,000 K/s, whereas pure boron cannot be ignited. Increasing the ratio or reducing the size of CuO can lower the ignition temperature of the powder. Furthermore, a high heating rate was believed to promote the interaction between CuO and boron particles. In the combustion test, 10 wt% nano-CuO can effectively accelerate the burn rate of submicron boron particles, with burn temperatures only slightly reduced. This study shows the potential of nano-CuO as an additive in boron-based fuels.