Experimental and numerical studies of fragmentation shells filled with advanced HMX-plastic explosive compared to various explosive charges

Abstract

The wide usage of TNT as a main charge for fragmentation shells has been eliminated due to its lower performance and exudation on the fuze thread and relevant safety measures inconvenience. These disadvantages have not become accepted anymore due to the desired safety requirements and the limited efficiency of the TNT, especially when different new explosives are introduced into researches. This research studies the fragmentation calculations of the 120 mm high explosive shell when its is loaded with different explosives rather than TNT. Different explosives have been used in the current research include the melt cast compositions such as Octol and composition B, a cast cured composition based on RDX with HTPB polymer matrix and the plastic explosive composition HMX-silicone. The fingerprint of the fragmentation pattern of each shell loaded with different explosive has been obtained using Autodyn smooth particle hydrodynamic (SPH) algorithm, whose numerical model has been validated with previous measurements using TNT explosive. Based on obtained numerical estimates, the HMX-silicone explosive has been proposed to replace the traditional TNT explosive material. This explosive has been then manufactured and casted into the studied 120 mm shell, where the experimental field pit test was established to collect, separate and analyse the resultant fragments. Current calculations and experimental results showed that the shell loaded by composition HMX-silicone produced the highest fragmentation velocities (i.e. 1.5 times that of TNT) and the largest number of fragments (i.e. 2.7 times that of TNT) with lower masses, which will be recommended for our next production stages instead of the traditional TNT.