Research Of HMX Gradation On The Properties Of TNT Based And DNAN/TNT Based Melt-Cast Explosives

Melt-cast explosives are kinds of widely used military explosives.Witfh the growing military demand for low-fragile insensitive explosives,the traditional TNT-based melt-cast explosives gradually failed to meet the needs of the modem military.In this study,the effect of HMX gradation on the properties of TNT-based melt-cast explosives was investigated.In addition,the properties of the eutectic mixture formed by TNT and DNAN were explored.Based on this,the effect of HMX gradation on the properties of TNT/DNAN-based melt-cast explosives was investigated.The research contents are as follows:First of all,the effects of different content and gradation ratio on the properties of TNT-based cast explosives were studied by using the small particle size and low sensitivity of the micro-nano HMX.TNT-based cast explosives were characterized by density homogeneity test,FESEM,TG-DSC,impact and friction sensitive test,etc.The comparison shows that HMX gradation can improve the comprehensive properties of TNT-based melt-cast explosives.Secondly,the DNAN/TNT eutectic mixture was prepared by DNAN and TNT.At the same time,the thermal properties of the DNAN/TNT was tested.TG-DSC analysis shows that TNT has a significant effect on reducing DNAN melting point.When the content of DNAN is 50%,the lowest melting point of DNAN/TNT is 66.4 ?.When DNAN content is between 10%and 70%,the melting points of DNAN/TNT eutectic mixture are lower than that of TNT.Finally,DNAN/TNT-based melt-cast explosives containing HMX gradation were prepared by using matrix ingredient composed of 70DNAN/30TNT,and then were subjected to FESEM,TG-DSC.The results show that the HMX gradation can also improve the comprehensive properties of DNAN/TNT-based melt cast explosives.The DNAN/TNT-based melt cast explosives have lower sensitivity and higher mechanical properties than traditional TNT-based melt cast explosives.The DNAN/TNT-based melt cast explosives with 65%coarse particle HMX have 38.0%lower friction sensitivity,145.3%higher compressive strength and 238.5%higher tensile strength than the traditional TNT-based melt cast explosives with 60%coarse particle HMX.