Combustion Performances of Smokeless Composite Modified Double-base(CMDB)Propellants Containing 2,6-Diamino-3,5-dinitro pyrazine-1-oxide(LLM-105)

The effect of content and particle size of 2,6-diamino-3,5-dinitro pyrazine-1-oxide(LLM-105),and different composite combustion catalysts(A-Pb/A-Cu/carbon black(CB),B-Pb/B-Cu/CB,C-Pb/C-Cu/CB)and assistant plasticizers(triacetate(TA),diethyl phthalate(DEP))on the combustion performances of smokeless composite modified double-base(CMDB)propellants was investigated by a burning rate-target line method.The results show that with increasing the LLM-105 content in the formulation of the propellant,the burning rates of propellant under different pressures are significantly decreased.Adding LLM-105 with mass fraction of 25%in the formulation of the propellant can make the value of burning rate of the propellant under the pressure of 10 MPa decrease by 53.3%.The effect of LLM-105 with coarse particles on decreasing the burning rate of propellant is better than LLM-105 with fine particles.Replacing same amount of LLM-105 with fine particles by LLM-105 with coarse particles can make the burning rate of propellant under different pressures decrease,especially the burning rate of propellant under 10 MPa reduces by 1.5mm/s.The propellant pressure exponent decrease from 0.43 to 0.25 when the C-Pb/C-Cu/CB catalyst system is used under 6-18 MPa.Replacing DEP in the formulation with TA can make the burning rate and pressure exponent of propellant reduce.