Study On The Formulation Design And Molding Technology Of Silicone Rubber Based Booster Explosive For Explosive Network

In view of the disadvantages of low curing rate and short applicable period of HTPB and GAP adhesive system,a trench charge formula with RTV（room temperature vulcanized）silicone rubber as the bonding system and HMX,CL-20 as explosive was designed,which can be detonated under the size of submillimeter charge.The synchronous explosive network of"one in and eight out"was tested by reverse synchronous microinjection charging mould,the technological conditions of charge were optimized,and the performance of charge was tested.The main research work was as following:（1）On the basis of fully considering the properties of charge forming effect,detonation critical size,compatibility,cost and detonation speed,the main explosives and binders were selected.First of all,the detonation transmission of explosives was analyzed,and the detonation transmission ability of simple explosive was estimated by combining the detonation speed and thermal decomposition temperature of explosives.The sequence of detonation transmission ability of four common explosives was:CL-20>PETN>HMX>RDX.Combined with detonation speed and cost,HMX and CL-20 were selected as the main explosives.Secondly,HMX and CL-20 were refined by solvent/non-solvent recrystallization method and mechanical milling method,respectively.The granularity of HMX,CL-20particles were obtained to be 50⁸0μm and 10μm,respectively,and the optimum ratio of them was determined to be 7:3.The curing process and curing mechanism of silicone rubber were compared and analyzed.In combination with the molding effect,1:1 RTV silicone rubber was selected as the binder.（2）The density of different solid content samples was tested and analyzed,and the relationship between molding density and solid content was studied.The range of solid content of CL-20、HMX explosive was obtained by combining the forming effect,and then the optimized formulation was obtained.The results show that the fitting equation between solid content and theoretical density percentage is Boltzmann equation,and the correlation was more than 99.5%.The molding density increases first and then decreases with the increase of solid content.The range of solid content of HMX and CL-20 is 80⁸6.48%and75.23⁸7.24%respectively.The optimized formula was:HMX:CL-20:silicone rubber=60:26.5:13.5.（3）In view of the"one in eight out"synchronous explosive network structure,a reverse synchronous charge mold was designed and the influence of temperature and solid content on the viscosity of the slurry was studied.The optimum loading process was as following:the temperature of the slurry was at room temperature,the precuring time was 50min,the pressure loading formula was slowly pressurized,the maximum pressure was not over 2.5t,and the pressure holding time was 3min.（4）The relative formability,thermal property,detonation property and impact sensitivity of the formulation were tested.The results showed that the density of the sample was 1.68g/cm³ under the optimized conditions.The critical thickness of detonation was 0.48mm（1mm groove width）and the measured detonation velocity was 7146 m/s（1mm*1mm）.The thermal stability of the sample was improved,due to the refinement of CL-20 by DSC differential thermal analysis,and the impact sensitivity of the sample was tested.The impact sensitivity(H₅₀=56.5cm)is lower than that of refined HMX（29.3cm）and refined CL-20（14.6cm）.