Effects of aging on mechanical sensitivity threshold and thermal decomposition characteristic of RDX/HMX

In order to analyze the influences of storage aging on the safety of typical elemental explosives, the aged cyclotrimethylene trinitramine (RDX) and cyclotetramethylene tetranitramine (HMX) were prepared by isothermal aging tests. The reaction thresholds of aged RDX and HMX under any ignition probability were studied by Langlie-Optimal D method. The thermal decomposition characteristics of RDX and HMX after aging were analyzed by DSC and ARC. Experimental results showed that compared with unaged RDX and HMX, on the one hand, the critical impact energy and critical friction of RDX and HMX aged for 14, 28, and 56 days are significantly reduced at an explosion probability of 50%, 0.01%, and 0.0001%, respectively. With the increase of aging time, the mechanical sensitivity of RDX and HMX increases obviously. On the other hand, the initial decomposition temperature of RDX and HMX after 56 days of aging decreases, the decomposition heat decreases, the activation energy increases, and the reaction difficulty increases.