Mechanism of Cu Effect on Energy Release of Al/Ni/Cu Energetic Composites

The improvement of mechanical properties and the reduction of the reaction energy release rate can make Al/Ni energetic composites have better penetration as fragment materials. In this paper, the influence mechanism of the addition and content of Cu particles on the mechanical properties and energy release of Al/Ni energetic composites has been studied in detail. The Cu deposited on the Al–Ni interface hinders the direct contact between Al and Ni and the rapid exothermic reaction, which increases the initial reaction temperature of Al/Ni energetic composites from 427 to 516 °C. However, the addition of Cu can significantly improve the plasticity of energetic composites. When the Cu content increased to 20%, the elongation of the composite increased by 29.7%. In the steady-state exothermic reaction process of Al/Ni/Cu energetic composites, Cu will hinder the solid–solid interface reaction between Al and Ni, enhance the sensitivity of the initial reaction, and reduce the rate of the exothermic reaction. In the process of shock-induced chemical reaction (SICR), Cu does not only participate in the exothermic reaction but also the hindrance of Cu particles leads to the decrease of the reaction rate. When the Cu content is 10%, the duration of the shock-induced chemical reaction is extended from 160 to 250 ms. The research on the energy release mechanism of Al/Ni/Cu energetic composites under steady-state heating and high-speed impact will provide an important theoretical basis for the practical application of this material.