DNP/HMX熔铸炸药的流变性能

To understand the rheological behavior of 3,4-dinitropyrazole(DNP)/HMX suspension under different influencing factors, the rheological properties of DNP/HMX suspension were tested by using a Brookfield R/S rheometer,and the effects of HMX content, particle size, particle gradation, system temperature and chemical additives on rheological behaviors of suspensions were measured. Results show that DNP is an Newtonian fluid and its apparent viscosity is about 16.4mPa•s, which is 82% higher than TNT and 140% higher than DNAN. At the same shear rate, the apparent viscosity of DNP/HMX melt-cast explosive suspensions increases with the increase of solid content. When the solid content is 30%, the suspension is similar to an Newtonian fluid. However, when the solid content is higher than 30%, the apparent viscosity decreases exponentially with the increase of shear rate. In addition, the apparent viscosity of suspensions decrease with the increase of particle size or system temperature. The flow activation energies increase from 29211J/mol to 38458J/mol when the temperature rises from 95℃ to 105℃. Furthermore, when the solid content is 60%, the optimal mass ratio of HMX particles with average particle size (d₅₀) of 16.6μm and 575.6μm is 1:5, and the apparent viscosity of suspension is the smallest. N-methyl-4-nitroaniline (MNA) makes the apparent viscosity of suspensions decrease, while cellulose acetate butyrate (CAB) and microcrystalline wax-80(MV80) make the apparent viscosity of suspensions increase.