Air explosion characteristics of a novel TiH$_2$/RDX composite explosive

An explosive mixture of cyclotrimethylenetrinitramine (RDX) and titanium hydride (TiH$_2$) is introduced. To investigate the explosion characteristics of the composite explosive, charges with various contents of the TiH$_2$ powder are prepared and tested in air explosion experiments. Results show that the peak overpressure, positive duration, and positive specific impulse increase as the content of TiH$_2$ increases from 10 to 20%, as compared to passivated RDX. The peak overpressure, duration, and specific impulse have the largest increase of 6, 9, and 23%, respectively, as compared to passivated RDX, when the TiH$_2$ content is 20%. The effect of the TiH$_2$ particle size is also considered. The charge containing the TiH$_2$ powder with a mean particle size of 4.6 mm shows higher values of the three parameters than that containing 45-mm TiH${}$ particles under the condition of the same content of TiH${}$. However, the relationship between the detonation velocity and TiH$_2$ content is a linear inverse proportion, and the particle size of TiH$_2$ has a minor effect on it. Solid explosion products of the TiH$_2$/RDX composite explosive are analyzed by x-ray photoelectron spectroscopy (XPS) and energy dispersive x-ray spectroscopy (EDX). TiO$_2$ is found in explosion products, which is believed to form due to TiH$_2$ oxidation.