Research On Improving The Performance Of Single Base Propellant

The development of modern weapon requires high energy power resource.To meet this requirement,high-energy oxidant(RDX)has been inputted into traditional gun propellants to improve their energy performances.It is of great importance to research the modified propellants’ energy properties,combustion characteristics and mechanical performance.To improve the energy of single-based propellant,modified single base propellant samples with RDX have been prepared with different RDX contents(5%,10%,15%and 20%)and different RDX particle sizes(0.20μm,3.70pm,7.60μm,100.00μm,9.33μm and 13.34μm),and different kinds of Nitrocellulose(NC).The combustion performances of these gun propellants with different RDX and NC are investigated by closed-bomb tests,and the energy properties of these propellants with different RDX contents and different kinds of NC are obtained.Combining the results of differential scanning calorimetry(DSC)tests,the combustion characteristics of these modified single base propellants are analyzed.The effects of RDX particle size,morphology,content and composition of nitrocellulose on the mechanical properties of the modified single-based propellant are investigated by means of tensile test,compression test and impact test,while the thermal expansion properties of the modified single-base propellant are studied by the static mechanical analysis(TMA)test,and the factors affect the mechanical properties of the modified single-base propellant are analyzed.The results show that the thermal decomposition process of the samples mainly contains the thermal decomposition of NC and RDX;the power force of the samples with 20%RDX is 11.37%and 6.93%higher than the single-base propellant and SF-3 gun propellant respectively.With the same content of RDX(5%),the burning rate of the samples increases and the mechanical properties present the downward trend with increasing particle size of RDX;the low temperature impact strength of the samples with 7.60μmRDX is-11.81%and 26.13%higher than it of the single-base propellant and SF-3 gun propellant respectively.When the particle size of RDX is 7.6μm,with the increasing content of RDX,the compressive strength and the tensile strength of the RDX modified single base propellant are slightly reduced when comparing with the original single base propellant,and the compressive strength at high temperature is equivalent to the SF-3 standard propellant.The results of the modified single base propellant with different NC composition show that,the sample with three kinds of NC(grade A,B,C)has a better comprehensive mechanical properties,when compared to the single-base propellant and SF-3 gun propellant,its low temperature impact strength is 49.45%and 113.74%stronger respectively.