3D Printing and Performance of NC-BNNSs Composites Energetic Materials

NC/BNNSs composites with BNNSs addition ranging from 0 wt% to 0.4 wt% were prepared by 3D printing. The microstructure, combustion performance and mechanical properties of NC/BNNSs composites were characterized using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS), differential scanning calorimeter (DSC), high-speed photography, bomb calorimeter and tensile strength testing. Results show that BNNSs have a diameter ranging from 20–350 nm and a thickness of 2.6 nm. The morphology of NC/BNNSs composites is regular, and there is no obvious interface between the internal layers. With the increase of BNNSs content in the NC/BNNSs composites, its initial thermal decomposition and exothermic peak temperature gradually decrease. Compared with pure NC, the activation energy of NC/BNNSs is significantly reduced after adding BNNSs. The minimum activation energy was observed for 0.1% BNNSs, with a value of 173.3 kJ·mol⁻¹, which is a decrease of ∼123 kJ·mol⁻¹ compared to that of NC. The maximum combustion rate of NC/BNNSs with 0.2% BNNSs was 12.7 mm·s⁻¹, which increased by 3.4 mm·s⁻¹ compared with the combustion rate of NC (9.3 mm·s⁻¹). The heat of combustion gradually decreases, while the tensile strength gradually increases.