DNP/HMX熔铸炸药成型工艺研究

Research on the Forming Process of DNP/HMX Melt-Cast Explosives

3,4-二硝基吡唑(DNP)在能量密度、安定性等方面性能优异,是具有广阔应用前景的新型熔铸炸药载体.为研究DNP基熔铸炸药装药工艺和成型规律,以DNP/HMX(40/60)熔铸炸药为实验配方,采用数值模拟与实验验证相结合的方法,研究冒口预热工艺对DNP/HMX熔铸炸药装药冷却凝固时间与装药缺陷的影响规律,并在此基础上通过数值模拟方法研究大尺寸DNP/HMX熔铸炸药成型工艺.结果表明:冒口预热工艺能够改变装药内部凝固顺序,保证补缩通道持续畅通,从而有效减少药柱内缩松产生;装药尺寸对炸药成型过程影响显著:随着装药尺寸增加,相同工艺条件下药柱冷却耗时大幅延长,缩松占比明显上升,需要更高冒口预热温度消除药柱内缩松;尺寸超过临界值后,仅靠冒口预热工艺已无法消除药柱内部缩松.

3,4-Dinitropyrazole(DNP)has excellent performance in energy density and safety,and it is a novel carrier explosive with broad application prospects.In order to study the process and forming law of DNP-based melt-cast explosives,DNP/HMX(40/60)were used as experiment materials,and the method of combining numerical simulation and experimental verification was used to study the effect of riser preheating process on the porosity reduction mechanism of DNP/HMX melt-cast explosives.The influence of riser preheating process on solidification time and charge defects was analyzed,and on this basis,the influence of the forming process in the process of large-scale DNP/HMX melt-cast explosives was studied.The results show that the riser preheating process can effectively reduce the porosity of the charge by changing the internal solidification sequence of the charge and ensuring the continuous action of the feeding channel during the charging process;the size of the charge has a significant impact on the explosive forming process:cooling time increases with model size;at high preheating temperature,the influence of model size on cooling time falls down;under the same process conditions,the larger the model size,the greater the proportion of porosity,and the greater preheating temperature required to eliminate the porosity of the charge;models within D200 mm can eliminate the porosity of the charge by preheating risers,while the porosity cannot be eliminated by the riser preheating process individually above a critical diameter.