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In this paper, the influence of the mass of Energetic Material (EM) and the relevant stand-off distance on the perforator charge performance has been investigated experimentally and numerically. An experimental program has been conducted, in which perforator charges have been constructed using different masses of an EM; where the relevant stand-off distances for the perforator charges have been changed accordingly. The constructed perforator charges with 33 mm in diameters are statically exploded against 1006 steel target and the depth of jet penetration for each tested perforator charge has been measured. Moreover, Autodyn-2D hydrocode is fed with the data of the constructed perforator charges to simulate their jet formation and its penetration process into 1006 steel target. The hydrocode predicts the dependence of the resultant jet velocity and its penetration depth into 1006 steel target on the mass of EM and the relevant stand-off distance. This dependence has also been confirmed by the corresponding static test results of small diameters perforator charges. Results show that the measured penetration depth increases from 11.0 to 13.7cm into 1006 steel target when the mass of EM increases from 36 to 41g and the relevant standoff distance decreases from 25.6 to 22.6 mm then; the penetration depth decreases again due to the limited standoff distance maintained for the tested perforator charges.

Million tons of explosives are used in mining, civil engineering, and military applications. Accidental detonation of these explosives due to mild impact loading during transportation and handling has been a significant concern. These explosions form highly localized temperature regions called ‘hot spots.’ However, the fundamental mechanism of hot spot formation remains elusive. An experimental investigation using ultrahigh-speed microscopy and high-speed visible imaging is performed in this study to reveal the hot-spot generation mechanism under mild impact loading conditions. A model particulate composite, with its constituents, has properties roughly equal to its counterparts in polymer-bonded explosives and is used to reveal the dominant heat-generating deformation mechanisms. The high-speed microscopic infrared full-field measurement of the model material under dynamic loading showed that the local heating is mainly concentrated in the binder solid inclusion interface region. On the other hand, a high spatiotemporal resolution deformation measurement on the model composites reveals that this local heating is mainly due to the sudden frictional relative movement between the inclusion and the binder.

Heat-resistant energetic materials refer to a type of energetic materials that possess a high melting point, high stability and operational safety. By studying the structures of these energetic materials has showed that the thermal stability can be enhanced by introducing amino groups to form intra/inter-molecular hydrogen bonds, constructing conjugate systems and designing symmetrical structures. This article aims to review the physical and chemical properties of ultra-high temperature heat-resistant energetic compounds and provide valuable theoretical insights for the preparation of ultra-high temperature heat-resistant energetic materials. We also analyze the selected 20 heat-resistant energetic materials with decomposition temperatures higher than 350 °C, serving as templates for the synthesis of various high-performance heat-resistant energetic materials.

In order to further improve the safety of RDX in preparation and application, the effect of polydopamine (PDA) on the performance of RDX was investigated, and the RDX/PDA composite was prepared by microfluidic technology. Composite morphology, structure, and thermal properties were evaluated using scanning electron microscopy (SEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and thermal analysis, respectively. The results show that the RDX/PDA composites are successfully prepared in one step, the particle size is 1~2 μm, the median particle size D 50 is about 0.98 μm, the span value is 0.54, the crystal structure is unchanged. The thermal decomposition activation of RDX/PDA is increased by about 23 kJ∙mol −1 , the thermal stability is improved, and the thermal decomposition mechanism is not changed.

Emulsion explosives (EE) have been commercially available in various forms for over 50 years. Over this period, the popularity and production technology of this class of energetic materials have been developing constantly. Despite this rapid rise to prominence and, in some applications, prevalence over traditional energetic materials, remarkably little information is available on the physicochemical and energetic properties of these materials and factors affecting those properties. This work is dedicated to presenting the fundamental information relevant to the features, properties and applications of EEs, while highlighting the most significant recent progress pertaining to those materials. Particular emphasis has been given to providing information about the types, composition, modifications and detonation parameters of EEs, as well as to highlighting the less obvious, emerging applications of EEs.

This article focused on 3,5-dimethyl-4-nitropyrazole (C 5 H 7 N 3 O 2 ) as the subject of research for hydrogen-bonded energetic materials. It examined the characteristics and properties of this organic crystal under high pressure using a diamond anvil cell (DAC) and Raman spectroscopy. High-pressure Raman spectroscopy studies indicate that 3,5-dimethyl-4-nitropyrazole does not undergo a phase transition at pressures up to 9.9 GPa, confirming the structural stability of this compound. Analyzing the Hirshfeld surface energy, fingerprint plots, and intermolecular interactions reveals that this stability is attributed to its unique screw structure.

The compatibility of erythritol tetranitrate (ETN) with RDX, CL-20, PETN, TNT, HMX, Picric acid was studied by differential scanning calorimetry (DSC). Two methods for judging the compatibility level of ETN and conventional explosives are introduced. One method is using the decomposition temperature ( T p ) and apparent activation energy ( E o ) of the thermal decomposition curve at the heating rate, the compatibility levels of the two explosives can be obtained. The results show that ETN with RDX have good compatibility, level 1; ETN with HMX, CL-20 are fair compatibility, level 2; ETN with PETN, TNT and Picric acid are poor compatibility, level 3. Another method is when apparent activation energy ( E o ) is not added, the compatibility levels are different when just used the decomposition temperature ( T p ).

The polytetrafluoroethylene/aluminum (PTFE/Al) granular composite, a common formulation in impact-initiated energetic materials, undergoes mechanochemical coupling reactions under sufficiently strong dynamic loading. This investigation discusses the dynamic properties and the constitutive relationship of the PTFE/Al granular composite to provide a preliminary guide for the research on mechanical properties of a series of composite materials based on PTFE/Al as the matrix. Firstly, the 26.5Al-73.5PTFE (wt.%) composite specimens are prepared by preprocessing, mixing, molding, high-temperature sintering, and cooling. Then, the quasi-static compression and Hopkinson bar tests are performed to explore the mechanical properties of the PTFE/Al composite. Influences of the strain rate of loading on the yield stress, the ultimate strength, and the limited strain are also analyzed. Lastly, based on the experimental results, the material parameters in the Johnson–Cook constitutive model are obtained by the method of piecewise fitting to describe the stress–strain relation of the PTFE/Al composite. Combining the experimental details and the obtained material parameters, the numerical simulation of the dynamic compression of the PTFE/Al composite specimen is carried out by using the ANSYS/LS-DYNA platform. The results show that the computed stress–strain curves present a reasonable agreement with the experimental data. It should be declared that this research does not involve the energy release behavior of the 26.5Al-73.5PTFE (wt.%) reactive material because the material is not initiated within the strain rate range of the dynamic test in this paper.

As a hot research topic, nano-scale energetic materials have recently attracted much attention in the fields of propellants and explosives. The preparation of different types of nano-sized energetic materials were carried out, and the effects of nano-sized energetic materials (nEMs) on the properties of solid propellants and explosives were investigated and compared with those of micro-sized ones, placing emphasis on the investigation of the hazardous properties, which could be useable for solid rocket nozzle motor applications. It was found that the nano-sized energetic materials can decrease the impact sensitivity and friction sensitivity of solid propellants and explosives compared with the corresponding micro-sized ones, and the mechanical sensitivities are lower than that of micro-sized particles formulation. Seventy-nine references were enclosed.

Energetic materials, characterized by their capacity to store and release substantial energy, hold pivotal significance in some fields, particularly in defense applications. Microfluidics, with its ability to manipulate fluids and facilitate droplet formation at the microscale, enables precise control of chemical reactions. Recent scholarly endeavors have increasingly harnessed microfluidic reactors in the realm of energetic materials, yielding morphologically controllable particles with enhanced uniformity and explosive efficacy. However, crucial insights into microfluidic-based methodologies are dispersed across various publications, necessitating a systematic compilation. Accordingly, this review addresses this gap by concentrating on the synthesis of energetic materials through microfluidics. Specifically, the methods based on micro-mixing and droplets in the previous papers are summarized and the strategies to control the critical parameters within chemical reactions are discussed in detail. Then, the comparison in terms of advantages and disadvantages is attempted. As demonstrated in the last section regarding perspectives, challenges such as clogging, dead zones, and suboptimal production yields are non-ignoble in the promising fields and they might be addressed by integrating sound, optics, or electrical energy to meet heightened requirements. This comprehensive overview aims to consolidate and analyze the diverse array of microfluidic approaches in energetic material synthesis, offering valuable insights for future research directions.