初始空腔体积率对约束HMX基PBX-3炸药慢烤相变的影响  

Effect of initial void ratio on phase transition of confined HMX-based PBX-3 under slow cook-off

作　　者：胡平超[1] 李涛[1] 刘仓理[2] 傅华[1] HU Pingchao;LI Tao;LIU Cangli;FU Hua(Institute of Fluid Physics,China Academy of Engineering Physics,Mianyang 621999,Sichuan,China;China Academy of Engineering Physics,Mianyang 621999,Sichuan,China)

机构地区：[1]中国工程物理研究院流体物理研究所,四川绵阳621999 [2]中国工程物理研究院,四川绵阳621999

出　　处：《爆炸与冲击》2023年第6期52-59,共8页Explosion and Shock Waves

摘　　要：为了认识慢烤过程中初始空腔体积率对HMX基PBX-3炸药热致相变以及点火响应特性的影响,设计了小尺寸强约束慢烤实验装置。在相同温升速率下,开展了空腔体积率分别为1.0%、4.2%和13.8%的约束PBX-3炸药慢烤实验,获得了炸药内部不同位置以及约束壳体表面的温度演变历程,对炸药中HMX相变过程、初始空腔体积率对HMX相变影响的机制、HMX相变进程对点火反应温度的影响进行了详细分析。结果表明:初始空腔体积率越小,HMX相变吸热表现出的温度平台持续时间越短,点火时刻约束壳体表面的温度越高。分析认为初始空腔体积率越小,慢烤加热至HMX相变温度时刻,PBX-3炸药受到的热应力越大,延缓了慢烤过程中β-HMX转化为δ-HMX的相变进程;由于δ-HMX的热感度更高,慢烤实验过程中HMX的相变进程越慢,δ-HMX放热分解反应引起的热量积累越慢,炸药点火反应时刻约束壳体的温度越高。In order to understand the effect of initial void ratio on the thermal phase transformation and ignition response characteristics of HMX-based PBX-3 under slow cook-off condition,a series of experiments were designed and conducted on the confined PBX-3 explosives with the initial void ratios of 1.0%,4.2%and 13.8%.In each test,the PBX-3 sample composed of two cylindrical pieces of explosive,25 mm in diameter and 10 mm in height for each,was prepared.The temperature was monitored by the five small-size type-K thermocouples,0.25 mm in width and 0.15 mm in thickness for each,among which four were arranged at the different positions in the interior of the PBX-3 and one was positioned on the surface of the shell.The experimental apparatus was positioned in a slow cook-off chamber with a transparent glass cover.The slow cook-off setup was heated to 150℃within 30 minutes,followed by a 45-minute soak at 150℃,and then heated at 0.25℃/min until thermal explosion occurred.During the process,the temperatures at different locations inside the explosive and at the surface of the shell were acquired.The process of the HMX phase transition,the mechanisms exhibiting the effect of the initial void ratio on the HMX phase transition and the effect of the HMX phase transition process on the thermal explosion temperature were analyzed in detail.The result shows that the lower the initial void ratio is,the higher the thermal stress the PBX-3 is subjected to when it is heated to the HMX phase transition temperature,which delays the transformation process ofβ-HMX intoδ-HMX during the slow cook-off.Due to the higher thermal sensitivity ofδ-HMX,the longer the phase transition process of HMX in the slow cook-off is,the slower the heat accumulation resulting from theδ-HMX exothermic decomposition reaction,and the higher the temperature of the confined shell at the time of thermal explosion.

关 键 词：空腔体积率 PBX-3炸药 HMX相变 慢烤实验 

分 类 号：O381[理学—流体力学] TJ55[理学—力学]