新型高能钝感炸药JBO-9X在较高冲击压力下冲击起爆过程的实验研究

采用高速扫描相机和楔形炸药构型,对新型高能钝感炸药JBO-9X的冲击起爆过程进行了实验研究;采用LS-DYNA软件对实验结果进行了数值模拟验证。结果表明,在6.9GPa的入射冲击压力下,JBO-9X炸药的冲击转爆轰时间为1.5μs,冲击到爆轰的距离为7.9mm;当冲击波刚进入炸药时,炸药发生化学反应的比例(λ)为0.2,随着冲击波进入炸药的距离增加,受试炸药中发生化学反应的比例逐步增加。在实验条件下,入射冲击波压力为6.85GPa时,JBO-9X炸药的冲击到爆轰距离为8.0mm。化学反应比例随冲击波进入炸药距离的增长曲线与实验基本相同。     

用电磁粒子速度计实验研究一种TATB基钝感炸药的冲击响应

针对一种新的TATB基钝感炸药(Tx),应用组合式电磁粒子速度计(EMV)测试技术,测量了炸药直接加载、增加有机玻璃隔板以及炸药驱动飞片3种加载状态下炸药内部的粒子速度历程和冲击波轨迹。根据测试结果,分析了不同加载压力下炸药的冲击响应过程。结果表明,炸药直接加载时,加载压力最高,Tx钝感炸药很快达到爆轰状态,到爆轰距离约为1.5mm;在增加有机玻璃隔板、加载压力为14.2GPa时,与直接加载时炸药粒子速度一致,Tx钝感炸药的到爆轰距离明显增加,约为5mm;在炸药驱动飞片、加载压力为9.5GPa时,Tx钝感炸药的粒子速度逐渐降低,存在一定钝化现象,到爆轰距离达到20mm以上。     

金属柱壳约束对非理想炸药驱动效率的影响

通过分析金属柱壳在内部炸药滑移爆轰作用下的动力学响应,建立了爆轰产物压力与壳体径向膨胀位移、材料动态屈服强度之间的关系式。基于Taylor假定确定了壳体完全破裂时爆轰产物压力的阈值。以两种具有相近格尼系数的RDX基含铝炸药为例,对该模型的适用性进行了验证。结果表明,相同壳体下,与无硝酸酯的RDX基含铝炸药相比,含硝酸酯的RDX基含铝炸药的驱动能量利用率具有明显优势。当壳体材料动态屈服强度从0.2GPa增至0.8GPa时,其有效作功能的相对增量约从7.5%迅速增大至15.2%,符合战斗部实际应用中的趋势,表明该分析模型可用于非理想炸药驱动作功性能的综合评价。     

固体炸药冲击起爆研究

为了研究固体炸药冲击起爆特性，对JO-9159炸药进行了隔板冲击加载实验，用高速摄影方法记录炸药冲击起爆过程；用解析计算方法分析了有机玻璃隔板的临界厚度值；建立了炸药冲击起爆模型，对起爆过程进行了数值模拟，计算了炸药在冲击作用下的压力历史，分析了JO-9159炸药起爆压力阈值和爆轰成长距离。     

CL-20基含铝炸药爆轰波阵面法向速度与曲率的关系

采用高速扫描相机及电探针测速法测量了具有相同铝含量的CL-20基和RDX基含铝炸药的拟定态爆轰波形及爆速,分析了炸药波阵面法向速度Dn与曲率κ之间的函数关系。结果表明,CL-20基含铝炸药的爆轰波阵面较RDX基含铝炸药的平坦,其法向爆速受曲率效应的影响也较RDX基含铝炸药的小。当κ0.005mm-1时,其法向爆速的下降速率明显小于RDX基含铝炸药;当κ0.005mm-1时,其法向爆速的下降速率略高于RDX基含铝炸药。     

聚能射流冲击起爆屏蔽压装PBX炸药的试验研究

为了分析由聚能射流引起的两种典型屏蔽压装PBX炸药的冲击起爆感度,采用某Ф80mm制式破甲弹作为标准射流源,在炸高为150mm的条件下,对不同厚度45~#钢覆盖板屏蔽的PBX-1和PBX-2炸药进行了射流冲击起爆感度试验;采用"兰利法"对覆盖板的厚度进行选取,得到了聚能射流引爆两种典型压装PBX炸药的临界隔板厚度。结果表明,临界爆轰时,PBX-1炸药覆盖板厚度为35～40mm,PBX-2炸药覆盖板厚度为140～150mm,即PBX-1的临界隔板厚度比PBX-2炸药减少73.3%;PBX-1炸药起爆所需的射流能量为185mm~3/μs~2,远高于PBX-2炸药,因此PBX-1炸药的射流安全性显著优于PBX-2炸药。     

Al粉对炸药爆炸加速能力的影响

采用电探针法测量了RDX基含铝炸药爆炸驱动金属薄片的速度变化,分析了铝粉含量对炸药爆炸加速能力的影响。结果表明,炸药爆炸对金属薄片的加速能力受配方中铝粉的反应比例影响;金属薄片的加速过程分速度增长和速度减小两个阶段;金属薄片达到最大速度的距离与铝粉的含量有关,随着铝粉含量的增加,达到最大速度的距离有所增加,该距离在40~60mm。铝粉含量对炸药爆炸加速能力的贡献有一最佳值,对于RDX基含铝炸药,其值约为15%。     

背板材料及炸药厚度对破片冲击起爆8701炸药装药的影响

为了研究背板材料及炸药厚度对破片冲击起爆8701炸药装药的影响,设计了单一破片和双破片冲击起爆屏蔽8701装药的试验。采用AUTODYN-3D软件进行数值模拟,通过改变背板材料及炸药厚度,来改变背板反射波的幅值,探究其对装药起爆阈值的影响。试验结果表明,在本研究装药结构下,除双破片撞击产生的冲击波叠加作用影响装药起爆的速度阈值外,背板反射波亦影响装药起爆的速度阈值。模拟结果表明,临界起爆速度随背板波阻抗的增大而减小;随炸药厚度的增大,背板反射波的作用逐渐减弱,当炸药厚度增大到30mm时,靠两钨球撞击产生的冲击波叠加起爆装药,背板对双破片冲击装药的临界起爆速度几乎无影响。     

硝酸酯对RDX基含铝炸药驱动能力的影响

为了研究硝酸酯对RDX基含铝炸药驱动能力的影响,采用圆筒试验研究了含硝酸酯的RDX基含铝炸药加速圆筒壁膨胀速度和格尼能的变化过程,并与不含硝酸酯的RDX基含铝炸药进行了对比,分析了硝酸酯对炸药能量释放特性及金属驱动能力的影响。结果表明,硝酸酯可改善RDX基含铝炸药的铝氧比,改变其反应速率;在反应初期,含硝酸酯的RDX基炸药加速筒壁的速度低于不含硝酸酯的炸药,而在爆炸反应中后期,含硝酸酯的RDX基炸药加速筒壁的速度以及格尼能均高于不含硝酸酯的炸药;含硝酸酯的RDX基含铝炸药的能量释放特性使其适合用于破片战斗部中,可提高其金属驱动能力。     

LX-04炸药大隔板试验的数值模拟

为研究不同条件下LX--04（HMX／氟橡胶／85／15）大隔板试验（LSGT）的冲击波感度G。,运用ANSYS／LS．DYNA对整个爆炸冲击波传爆过程进行了数值模拟,观察了LSGT中爆轰冲击波的传播过程,分别讨论了主发炸药PE4、TNT、B炸药产生的爆轰波经过有机玻璃隔板、铝隔板、钢隔板衰减后的冲击波压力变化情况,最终找出了3种不同主发炸药和3种隔板下LX-04冲击波感度G50。同时,定性地分析了3种隔板对爆炸冲击波的衰减系数。其中,铝隔板的衰减系数最大,有机玻璃隔板的衰减系数最小。     

RDX基铝薄膜炸药与铝粉炸药水下爆炸性能比较

为了减少铝粉炸药在生产过程中因铝粉对环境污染,降低铝粉炸药的撞击感度,提高含铝炸药的成型性及力学性能,将RDX用铝薄膜分层包裹得到新型的铝薄膜混合炸药。将铝薄膜混合炸药与铝粉炸药进行水下爆炸实验与爆速实验,得到两种炸药的爆速与压力时程曲线,经过分析计算得到两种炸药的压力峰值、冲量、冲击波能、气泡脉动周期与气泡能。结果表明：铝薄膜炸药药柱的轴向为RDX与铝薄膜独立贯通的结构,有利于降低混合炸药中添加物对基体炸药爆轰波传播的影响,从而使铝薄膜混合炸药的爆速高于铝粉炸药,导致铝薄膜炸药的冲击波损失系数高于铝粉炸药,使铝薄膜混合炸药的总能量、比气泡能与铝粉炸药相当情况下,其比冲击波能却降低了10.16%～10.33%,计算过程说明铝薄膜混合炸药的C-J压力计算公式具有合理性。     

Laboratory‐Scale Method for Estimating Explosive Performance from Laser‐Induced Shock Waves

A new laboratory‐scale method for predicting explosive performance (e.g., detonation velocity and pressure) based on milligram quantities of material is demonstrated. This technique is based on schlieren imaging of the shock wave generated in air by the formation of a laser‐induced plasma on the surface of an energetic material residue. The shock wave from each laser ablation event is tracked for more than 100 μs using a high‐speed camera. A suite of conventional energetic materials including DNAN, TNT, HNS, TATB, NTO, PETN, RDX, HMX, and CL‐20 was used to develop calibration curves relating the characteristic shock velocity for each energetic material to several detonation parameters. A strong linear correlation between the laser‐induced shock velocity and the measured performance from full‐scale detonation testing has been observed. The Laser‐induced Air Shock from Energetic Materials (LASEM) method was validated using nitrocellulose, FOX‐7, nano‐RDX, three military formulations, and three novel high‐nitrogen explosives currently under development. This method is a potential screening tool for the development of new energetic materials and formulations prior to larger‐scale detonative testing. The main advantages are the small quantity of material required (a few milligrams or less per laser shot), the ease with which hundreds of measurements per day can be obtained, and the ability to estimate explosive performance without detonating the material (reducing cost and safety requirements).     

Research on the Size of Defects inside RDX/HMX Crystal and Shock Sensitivity

Intragranular defects inside RDX/HMX were studied by optical microscopy with matching refractive (OMS), sink‐float method (SFM), and micro‐focus CT (μCT) techniques. OMS results revealed the phenomenon that RDX/HMX had more defects and cracks than RS‐RDX/RS‐HMX. μCT results indicated that RDX/HMX had more defects with larger volume than RS‐RDX/RS‐HMX. The gap test showed that critical shock pressure/gap thickness was 6.4 GPa/19.4 mm for PBX based on RDX, while they were 7.5 GPa/17.5 mm and 8.6 GPa/16.2 mm for PBX based on M‐RDX and RS‐RDX, respectively. Meanwhile, an analysis of the relationship between defects inside RDX/HMX crystal and shock sensitivity was made. Finally, the shock pressure response under impact loading was investigated by discrete element method.     

A Low‐Sensitivity Composition Based on FOX‐7

1,1‐Diamino‐2,2‐dinitroethene (DADNE, FOX‐7) is considered to be an explosive combining comparatively high performance and low sensitivity. In the present study, FOX‐7 has been evaluated as a possible replacement of RDX in TNT‐based melt‐cast compositions. A composition containing FOX‐7, TNT, Al and wax, and a method of preparing it were proposed. Its sensitivity to impact, friction, shock wave, jet impact, fast heating, and its thermal stability were tested. Some detonation parameters like the detonation pressure, velocity and heat were measured. Moreover, the Gurney velocity, the so‐called effective exponent of the expansion isentrope and the JWL equation of state of the detonation products were determined from the results of a cylinder test. The detonation characteristics were compared with that obtained for cast TNT.     

聚黑-14C的传爆装置冲击起爆实验及数值模拟

基于聚黑(JH)-14C传爆药的小隔板试验方法及结果,建立了小隔板试验有限元模型并进行了模拟计算,确定了密度为1.65g/cm~3时JH-14C的Lee-Tarver参数。以RDX-8701为主发药柱,对实际装药条件下JH-14C的传爆装置进行了冲击起爆实验,得到了钢鉴定块的凹坑深度。根据小隔板试验确定的JH-14C传爆药Lee-Tarver参数,建立了全尺寸的冲击起爆实验有限元模型,并对比分析了模拟结果与实验结果,通过改变导爆药柱顶部的钢隔板厚度,确定了JH-14C的传爆装置发生冲击起爆的临界钢隔板厚度。结果表明,冲击起爆实验中钢鉴定块的凹坑深度约为2.1mm,模拟计算结果与实验结果基本吻合;JH-14C的传爆装置冲击起爆的临界钢隔板厚度在4~5mm。     

Effect of Al/O Ratio on the Detonation Performance and Underwater Explosion of HMX‐based Aluminized Explosives

The performance of detonation and underwater explosion (UNDEX) of a six‐formula HMX‐based aluminized explosive was examined by detonation and UNDEX experiments. The detonation pressures, detonation velocities, and detonation heat of HMX‐based aluminized explosive were measured. The reliability between the experimental results and those calculated by an empirical formula and the KHT code was verfied. UNDEX experiments were carried out on the propagation of a shock wave and a bubble pulse of a 1 kg cylindrical HMX‐based aluminized explosive underwater at a depth of 4.7 m. Based on the experimental results of the shock wave, the coefficients of similarity law equation for the peak pressure and attenuation time constant of shock wave were in acceptable agreement. The bubble motion during UNDEX was simulated using MSC.DYTRAN software, and the radius time curves of bubbles were determined. The effect of the aluminum/oxygen ratio on the performance of the detonation and UNDEX for an HMX‐based aluminized explosive was discussed.     

Underwater detonation performance of the aluminum film explosive

A new aluminized explosive is proposed, and the approach is to replace the aluminum powder in the traditional aluminized explosive with an aluminum film. The purpose is not only to improve mechanical properties and lower the impact sensitivity of traditional aluminized explosives, but also to reduce environmental pollution in the aluminum particle production process. The pressure-time curves of the aluminum film explosive and RDX are measured in underwater explosion experiments. The peak pressure, impulse, shock wave energy, and bubble energy are obtained by analyzing the curves. The results of the study indicate that the peak pressure of the aluminum film explosive is lower than that of RDX. However, the aluminum film explosive maintains a high pressure for a longer period of time. The large amount of energy is found to liberate by subsequent reactions of the Al film with the primary detonation products. The increase in the explosion energy of the aluminum film explosive is based mainly on the increase in the bubble energy.     

Detonation propagation in thin explosive layers with inert partitions

This paper describes the experimental results in the study of detonation transfer in thin layers of a PVV-12M plastic-bonded explosive (90% of RDX and 10% of bond) through solid and perforated partitions. The critical thicknesses of steel or Plexiglas partitions, exceeding which makes detonation transfer impossible, are determined for the explosive layers with a thickness of 2–12 mm. It is shown that shock waves in the plates, which bound the explosive charge, can stay ahead of the initiating shock wave in the passive part of the explosive charge and load the explosive charge from the lateral surface. Thus, the peripheral desensitized layers of the explosives are formed, which reduce the layer thickness of the detonable explosive and complicate the detonation transfer. Detonation transfer through the partitions whose thickness is greater than the critical thickness can be carried out with the use of holes in the partition, closed by thin plates. The plate thicknesses at which detonation propagates through the hole either in forward and reverse directions or in the forward direction only, are determined.