Energy release behavior of Zr/B/KNO3 dual-fuel energetic composites: Powders and sticks

Abstract

To enhance the reactivity of B/KNO3 (BPN) energetic composites and study the energy release behavior of energetic sticks, Zr/KNO3 (ZPN) was added to the BPN energetic system, and the energetic sticks with different ZPN/BPN ratios and different thicknesses were prepared by direct ink writing (DIW). In addition, the pore-size distribution, thermal decomposition characteristics, combustion characteristics, and pressure release characteristics of the different energetic sticks were studied. Considering this, the flame propagation behavior of the energetic powders and sticks was examined. The results demonstrate that energetic sticks with different ZPN/BPN ratios and thicknesses exhibit a consistent pore-size distribution. With increasing ZPN content, the peak temperature of the condensed phase reaction of the composite decreased from 479.9 °C to 362.1 °C, the reaction enthalpy increased from 879.5 to 3200.4 J·g−1, and the burning rate of the energetic sticks increased from 62.1 to 136.8 mm·s−1, indicating that the addition of ZPN improved the reaction characteristics of the composite. In addition, the reactivity of the energetic sticks can be regulated by adjusting their thickness With the increase of layers, the burning rate of energetic sticks increases from 58.6 mm·s−1 to 113 mm·s−1. The burning rate–time curves of all energetic sticks show different numbers and ranges of platforms. In comparison to energetic powder, energetic sticks exhibit lower pressure release and pressurization rates but a longer reaction time. This study provides valuable insights into the microscale reactivity regulation of BPN energetic composites and their application in microenergy devices.