A facile and effective strategy for modifying combustion of Zr/KClO4 via adding Si

Abstract

As a commonly applied ignition composition, Zr/KClO4 has attracted various interests and plenty of efforts have been made to improve the combustion performance. In this study, Si nanoparticles were incorporated into Zr/KClO4 by sonication. Around 2.5× peak pressure and 9.2× reactivity were achieved by Si/50%Zr/KClO4 when compared to Zr/KClO4. In addition, the peak pressure and pressurization rate of Si/Zr/KClO4 ternary systems are all superior to ones of both Zr/KClO4 and Si/KClO4 binary systems. The synergetic effect of Si/Zr/KClO4 is a combination of shorter ignition delay of Zr/KClO4 and more gas production of Si/KClO4, which is also reflected on the higher flame propagation rate of Si/Zr-based thermites than composites with pure Si or Zr as the fuel. Meanwhile, the heat release during the redox reaction has been measured. The results show ∼700–1000 J/g higher energy release than Zr/KClO4, and higher combustion efficiency can be attained by ternary systems than binary ones. Thus, adding Si powders is an effective way to improve the energetic behavior of Zr/KClO4 ignition composition, and Si/Zr/KClO4 ternary composites can be a promising candidate for application in pyrotechnics.