Inhibition Of Interfacial Damage Of Polymer Bonded Explosive By Low Pressure Under Variable Temperature

Polymer-bonded explosive(PBX)is a high-energy,interface-sensitive composite material widely used in the military field.PBX will undergo temperature changes over a wide range during storage and use.Experiments have shown that temperature changes will cause interfacial damage of the PBX,greatly affecting the safety and detonation performance of explosives.Therefore,it is very important to suppress interface damage.In this paper,the RVE model of PBX is constructed based on the Voronoi method.The numerical simulation is used to explore the mechanism of interface damage at variable temperature and the inhibition of pressure on interface damage.The relationship between displacement,interfacial stress,relative density and interface damage of PBX explosive under single temperature change and under dual conditions of temperature change and applied pressure was analyzed.This article also fits the relationship between the interface normal stress and the pressure in the cooling stage,and finally explores the effect of the thickness of the binder on the interface damage in the cooling stage,and the variation of the optimal pressure to suppress the interface damage with the thickness of the binder.The results show that the initial damage is mainly caused by the tangential stress of the interface during the heating phase,and the interface is debonded due to the normal stress of the interface during the cooling phase.The cooling is more likely to cause interface damage than the heating.To suppress the interface damage,the cooling process requires bigger pressure than the heating.The process requires pressure,but excessive pressure may cause new damage.When the relative density is close to 1,the interface damage is minimum while the temperature is rising,which can be attributed to the fact that the pressure inhibits the expansion of the PBX,making it closest to the initial state;when the relative density of the PBX explosive changes slowly during the cooling period,the interface damage is the smallest,which is related to the pressure.When the relative density of PBX increases slowly in the cooling stage,the interface damage is minimal,which is related to the movement and interaction of particles and binders in the PBX under pressure.The study also found that the E index can be used to fit the curve of the interface normal tensile stress with the pressure change in the cooling stage to predict the interface normal tensile stress under different pressures.What's more,the thicker the binder,the larger the interface damage,the greater the optimal pressure for suppressing the interface damage while in the cooling stage.So far,to study the influence of temperature changes on the interface performance of PBX,more experimental studies have been used,and few theoretical and numerical simulation methods have been used,especially for the study the suppression of interface damage under low temperature by varying temperatures.The analysis results in this paper can be corroborated with the relevant experimental results,and provide theoretical guidance for suppressing the interface damage of PBX explosives at variable temperature.The analysis results in this paper can be corroborated with the relevant experimental results,and provide theoretical guidance for suppressing the interface damage of PBX explosives at variable temperature.