However, boron particles are easily agglomerated owing to their larger specific surface area and denser structure. In addition, the combustion performance of thermites can also be improved by adopting appropriate preparation procedures, including ultrasonic mixing and arrested reactive milling. However, the disadvantages of Bi 2O 3, such as high electrostatic sensitivity or low ignition thresholds, pose a hidden threat during the processes of transportation and storage. studied the combustion performance of B/Bi 2O 3 by rapid heating (>10 5 K/s) temperature-jump/time-of-flight mass spectroscopy, which indicated that B/Bi 2O 3 can be ignited at a temperature as low as 520 ☌. studied the influence of varieties of metal oxides (MgO, Al 2O 3, Bi 2O 3, Fe 2O 3, etc.) by adding them to B particles, and the results revealed that Bi 2O 3 can decrease the ignition temperature by 15.2%. reported that the reaction temperatures of nano-B/NiO and nano-B/CuO particles were 30 ☌ and 116.86 ☌ lower than that of B particles, respectively. Recently, to overcome these challenges of B, different metal oxides have been chosen to enhance the combustion performance of B. However, applications of B-based thermites are limited due to their high ignition temperature and low combustion efficiency, making the combustion of thermites difficult. In comparison to Al, boron (B) has higher volumetric and gravimetric calorific values. The main studies about thermites have focused on aluminum (Al)-based thermite, e.g., Al/CuO, Al/Fe 2O 3, etc. Therefore, they have been widely used for various applications, such as explosions, pyrotechnics, and micro-actuators. Thermite is a mixture of metal and metal oxide or non-metal oxide, which can release a lot of heat upon ignition. In addition, the laser ignition energy required for B/NC/CuO microparticles was also reduced from 70 to 45 mJ. Between −50 ☌ to 55 ☌, the burning rate of B/NC/CuO increases by 14.16% from an initial rate of 13.35 mm⋅s −1. Combustion is barely affected by ambient pressure. Compared with the ball milling sample, the standard deviation of the burning rate of the electrosprayed sample was reduced by 32%. The optimum formula was observed for micro particles with 11 wt% B content. The particles are ignitable and burn consistently with minor variations in the conditions: B content (8.3–17%), ambient temperature (−50–55 ☌), and ambient pressure (0.02–0.1 MPa). Scanning electron microscopy results show that the sizes of these particles mostly lie in the range of 3–4 μm. The burning rate dependency on boron content, ambient temperature, and pressure was estimated by compressing B/NC/CuO micro particles into columns. To improve the combustion stability and ignition performance of thermite, B/NC/CuO micro particles were prepared from boron (B), nano copper oxide (CuO), and nitrocellulose (NC) as an energetic binder through the electrospray technique.
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