Research On The Thermal Conductivity And Performance Of Carbon Filler/RDX Composites

Thermal conductivity is a physical parameter which describes heat conduction performance of materials.It expresses that the heat transfer rate of vertical direction through per unit area and per unit temperature gradient in the stable condition.Its unit is W·m-1·K-1.The thermal conductivity of explosive is one of the key parameters which can analysis physical parameters of structural reliability and assessment safety performance.In this paper,we examined the thermal conductivity,the impact sensitivity and the electrostatic spark sensitivity of composite materials.By combining different high thermal conductivity fillers to strengthen the thermal conductivity,we improve the thermal properties of the composite successfully.At the same time,we explored the quantity of the fillers influence on the heat conduction performance of the explosives.1、We prepared carbon/RDX composite materials by adding different fillers of graphite,graphene,carbon nanotubes and carbon fiber dispersed in RDX matrix.In a relatively low amount of filling(1%,3%,5%),the highest thermal conductivity of the composite materials is 0.55 W·k-1·m-1,which is much higher than the thermal conductivity 0.106 W·k-1·m-1 of the pure RDX.The improvement of thermal conductivity is because of the thermal conductive network.In the process of pressurized solidification,the fillers contact each other more effectively.In the process of filling carbon,we use ultrasonic dispersion and mechanical stirring filler to disperse the fillers.2、In this paper,we summarized the common calculation methods of the thermal conductivity of polymer and collected the experimental value of thermal conductivity which is published.We Choose two methods to calculate the thermal conductivity of materials.Then introduced in conjugated polymers contain groups of-NO2,-N3 and-ONO2 to design several new contain conjugated polymers.We calculate the thermal conductivity of the new designed conjugated polymers.The result shows that the new designed conjugated polymers have higher thermal conductivity compared to the other polymers.3、In this paper we carried on the electrostatic spark sensitivity and impact sensitivity experiments of RDX/carbon to explore the relationship between the thermal conductivity and the sensitivity of explosives.Results show that there is a positive correlation between thermal conductivity of the RDX and impact energy.The greater the thermal transfer is,the greater energy needed to detonate the explosive,which means lower impact sensitivity.For doping different kinds of fillers in the RDX matrix,the highest thermal conductivity is graphene RDX matrix and its impact sensitivity is the lowest.Which proved that the relationship between the thermal conductivity and the mechanical sensitivity.The thermal conductivity and the impact energy of RDX/graphene are all increased compared with pure RDX’s.With the increasing of graphene filler content,the impact sensitivity is decreasing.The reason is that the heat conductivity pathway is build up by adding the fillers.The heat can spread along the pathway.The heat dissipation ability enhanced means the heat can be released more quickly,which reduces the impact sensitivity of RDX composites.