Research On The Safety Characteristics And Formulation Design Of HTPE Solid Propellant

In order to investigate the safety characteristics of the new high-energy insensitive propellant,two group HTPE insensitive solid propellants were designed by theoretical calculation and the thermal safety characters were studied.The thermal decomposition characteristics of 173 and 176 were observed by differential scanning calorimetry(DSC)and adiabatic acceleration calorimeter(ARC).In DSC test,the heating rates wereset to 1?/min?2?/min?4?/min?8?/min and 10?/min.The onset decomposition temperature of 173 and 176 were 158.48??161.73??166.86??170.79??183.86? and 139.27??148.82??172.74??175.02??175.56?,respectively,which was enhanced with increasing of heating rates.The adiabatic reaction temperatures predicated by AKTS were 125? and 127?,respectively.The ARC test results showed that there were three exothermic stages in the decomposition of of 173 and 176,the first onset decomposition temperature were 125.30 ? and 120.38?,respectively,which were lower than that measured by DSC,but close to the predicatevalues.The response characteristics of 173 and 176 to thermal stimulation were carried out by slow cook-off test at different scales.The reaction temperature of 173 and 176 were measured to be 114.6? and 115.4? under the condition of small sample without package,and they were129.8? and 122.5? when there was a package constraint.Both reaction temperature were very close while the destruction effect of 176 was far higher than that of 173.It can be concluded that,thermosensitivity were nearly uniform when the composition of propellants were similar.However,the damage effect was remarkably improved when a small amount of HMX was added into the propellants.In addition,the reactive temperature at adiabatic condition calculated by AKTS and values obtained by DSC and ARC were found to be almost identical,so AKTS could be used to estimate the adiabatic reaction temperature of HTPE.