Evaluating the enhancing potential of metal hydride in high explosives using a simulation approach

Abstract

Modelling and simulation in energetic materials (EM) is a well-known field and it keeps on growing and improving. Being able to simulate the EM before doing synthesis or formulation in the laboratory is a safe route. By using the right simulation tools, the performance parameters such as enthalpy of formation, detonation pressure, detonation velocity and sensitivity can be estimated.Metals are known as enhancing additives to energetic materials and are used to make enhanced explosive composites. Metal hydrides are derived from pure metals or metalloids which can be covalently or ionicallybonded to hydrogen. Metal hydrides havealso been used to enhance the EM performance parameters such as specific impulsesfor solid propellant.In this work theoretical formulation optimization was done for 2,4,6-trinitrotoluene (TNT), 1,3,5-Trinitroperhydro-1,3,5-triazine (RDX), 2,2Bis[(nitroxyl)methyl]propane-1,3-diyl dinitrate (PETN) and composition B with Alane (AlH3), magnesium hydride (MgH2), titanium hydride (TiH2), Zirconium hydride (ZrH2), lithium aluminium hydride (LiAlH4) and sodium aluminium hydride (NaAlH4). The theoretical density and detonation properties of the formulations were estimated with EXPLO5. The densities of the formulations were observed to be affected by the addition of metal hydrides. Where the metal hydrides are made from heavy metals, formulation density increased with increasing metal hydride quantities and the lighter metal hydrides did the opposite. Despite the observed increase in density for some formulations, this did not translate into more increased detonation pressure except for the TNT formulation with ZrH2. AlH3performed well for all the explosives, including PETN formulation.