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The incorporation of reactive material damage element technology in ammunition warheads is a research hotspot in the development of conventional ammunition. The research results are of great significance and military application value to promote the development of high-efficiency damage ammunition technology. In this paper, we aimed to understand the behavior of the reactive jet and its damage effect on a steel target by undertaking theoretical analysis, numerical simulation, and experimental research. We studied the influence of structural and material parameters on the shape of the reactive jet based on autodyn-2d finite element simulation software, and the formation behavior of the reactive jet was verified using a pulsed X-ray experiment. By studying the combined damage caused by the steel target penetrating and exploding the reactive jet, the influence of the structural and performance parameters, and the explosion height of the reactive jet liner on the damage effect to the steel target was studied. A static explosion experiment was carried out, and the optimal structural and performance parameters for the reactive material and explosion height of the reactive jet liner were obtained.

A series of impact fuel tank experiments are carried out through the ballistic impact method. The ignition abilities of Bi2O3-reinforced PTFE/Al reactive material, metal aluminum, and inert metal steel are compared and analyzed, and the ignition mode of kerosene is explored when PTFE/Al/Bi2O3 impacts the fuel tank at different velocities. The results offer that PTFE/Al/Bi2O3 reactive material has outstanding ignition ability, and the order for ignition ability is PTFE/Al/Bi2O3 reactive material, metal aluminum, and inert metal steel. The kerosene content of the fuel tank has a significant impact on the ignition effect. The ignition effect of PTFE/Al/Bi2O3 reactive material impacting the fuel tank filled with 50% kerosene is weaker than that impacting the full tank. Under different impact velocities, PTFE/Al/Bi2O3 reactive materials display diverse ignition modes for kerosene: kerosene is directly ignited by the flame in the reverse reaction zone under low-velocity conditions, while high-temperature-activated reactive fragments are the ignition heat source of high-velocity conditions.

Structural reactive material (SRM) is consolidated from a mixture of micro- or nanometric reactive metals and metal compounds to the mixture theoretical maximum density. An SRM can thus possess a higher energy density, relying on various exothermic reactions, and higher mechanical strength and heat resistance than that of conventional CHNO explosives. Progress in SRM solid studies is reviewed specifically as an energy source for air blast through the reaction of fine SRM fragments under explosive loading. This includes a baseline SRM solid explosion characterization, material properties of an SRM solid, and its dynamic fine fragmentation mechanisms and fragment reaction mechanisms. The overview is portrayed mainly from the author’s own experimental studies combined with theoretical and numerical explanation. These advances have laid down some fundamentals for the next stage of developments.

The objective of this study was to prepare an adsorbent material from eggshells of chicken banished to the ambient as wastes to satisfy the ecological requirements of sustainable. The preparation process based on the extraction of calcium ions from eggshells and these ions must be reacted with iron to form nanoparticles of (Ca/Fe)-layered double hydroxides (LDHs) which immobilized as Na-alginate beads. Molar ration of calcium to iron, pH and dosage of LDH nanoparticles must be equal to 1, 12 and 5 g/100 mL to ensure that the prepared beads have highest ability to remove of Amoxicillin (AMOX) antibiotic with removal efficiency equal to 32% for operational conditions of Co=100 mg/L, beads dosage=0.5 g/50 mL, speed=200 rpm, pH=7 for 3 hrs. To increase this efficiency to ≥ 90%, best conditions must be time 90 min, pH 7, and beads mass 1.2 g/ 50 mL for Co 100 mg/L at 200 rpm in the batch mode. The Pseudo second order has high capability in the description of such tests with coefficient of determination (R2) ≥ 0.9924 and sum of squared error (SSE) ≤ 0.1287. Hence, the sorption of AMOX onto beads is governed by the chemisorption process. The reflections of XRD analysis proved the presence of (Ca/Fe)-LDH nanoparticles with size of 13.49 nm, calcium hydroxide (Ca(OH)2) and calcium carbonate (CaCO3)

Reactive material (RM) is a special kind of energetic material that can react and release chemical energy under highly dynamic loads. However, its energy release behavior is limited by its own strength, showing unique unsustainable characteristics, which lack a theoretical description. In this paper, an impact-initiated chemical reaction model is proposed to describe the ignition and energy release behavior of Al/PTFE RM. The hotspot formation mechanism of pore collapse was first introduced to describe the decomposition process of PTFE. Material fragmentation and PTFE decomposition were used as ignition criteria. Then the reaction rate of the decomposition product with aluminum was calculated according to the gas-solid chemical reaction model. Finally, the reaction states of RM calculated by the model are compared and qualitatively consistent with the experimental results. The model provides insight into the thermal-mechanical-chemical responses and references for the numerical simulation of impact ignition and energy release behavior of RM.

The formation characteristics of reactive material (RM) composite jet were studied by finite element software AUTODYN. The effect of diameter and thickness ratio, and cone angle of the liner on the tip velocity of composite jet and effective jet length were investigated. In numerical simulations, with increasing of the ratio of liner diameter, the ratio of liner thickness and the liner cone angle, the tip velocity of the composite jet decrease. With increasing of the liner cone angle, the effective length of composite jet decreases. But it is almost independent of the liner diameter and thickness ratio. When the liner diameter ratio is 0.6-0.8, the liner thickness ratio is 0.1-0.2, and the cone angle of composite liner is 60°-80°, the comprehensive performance of the RM-composite jet is better.

The density evolution behaviour and distribution characteristics of the explosively formed reactive material jet were studied based on the SPH algorithm. Numerical simulations show that the reactive material jet has obvious expansion phenomenon under the shaped charge effect. Especially, the expansion and divergence of the jet head are obvious. In general, the density deficit occurs in the whole reactive material jet, and the density increases from the jet head to the tail. Compared with the initial density of the reactive liner material, the density of jet head decreases by about 30%. In addition, the effect laws of the reactive liner thickness, the liner cone angle, and the type of explosive on the jet density distribution were investigated. With increasing of the reactive liner thickness, increasing of the liner cone angle, and decreasing of the explosive detonation pressure, the proportion of the high-density area on the reactive jet and the average density of the jet head increase.

The reactive materials filled structure (RMFS) is a structural penetrator that replaces high explosive (HE) with reactive materials, presenting a novel self-distributed initiation, multiple deflagrations behavior during penetrating multi-layered plates, and generating a multipeak overpressure behind the plates. Here analytical models of RMFS self-distributed energy release and equivalent deflagration are developed. The multipeak overpressure formation model based on the single deflagration overpressure expression was promoted. The impact tests of RMFS on multi-layered plates at 584 m/s, 616 m/s, and 819 m/s were performed to validate the analytical model. Further, the influence of a single overpressure peak and time intervals versus impact velocity is discussed. The analysis results indicate that the deflagration happened within 20.68 mm behind the plate, the initial impact velocity and plate thickness are the crucial factors that dominate the self-distributed multipeak overpressure effect. Three formation patterns of multipeak overpressure are proposed. •The space distribution model of equivalent deflagration points of reactive material filled structure (RMFS) is developed.•The analytical model describing the self-distributed deflagration behavior of RMFS is developed.•The formation mechanism of multi-peak overpressure subjected to sequential impact and chemical deflagration is revealed.•Three multipeak overpressure patterns caused by spatiotemporal and multi-source deflagration are discussed.

The penetration enhancement behaviors of a reactive material double-layered liner (RM-DLL) shaped charge against thick steel targets are investigated. The RM-DLL comprises an inner copper liner, coupled with an outer PTFE (polytetrafluoroethylene)/Al reactive material liner, fabricated via a cold pressing/sintering process. This RM-DLL shaped charge presents a novel defeat mechanism that incorporates the penetration capability of a precursor copper jet and the chemical energy release of a follow-thru reactive material penetrator. Experimental results showed that, compared with the single reactive liner shaped charge jet, a deeper penetration depth was produced by the reactive material-copper jet, whereas the penetration performance and reactive material mass entering the penetrated target strongly depended on the reactive liner thickness and standoff. To further illustrate the penetration enhancement mechanism, numerical simulations based on AUTODYN-2D code were conducted. Numerical results indicated that, with increasing reactive liner thickness, the initiation delay time of the reactive materials increased significantly, which caused the penetration depth and the follow-thru reactive material mass to increase for a given standoff. This new RM-DLL shaped charge configuration provides an extremely efficient method to enhance the penetration damage to various potential targets, such as armored fighting vehicles, naval vessels, and concrete targets.

In order to study the microscopic reaction mechanism and kinetic model of Al/PTFE, a reactive force field (ReaxFF) was used to simulate the interface model of the Al/PTFE system with different oxide layer thicknesses (0 Å, 5 Å, 10 Å), and the thermochemical behavior of Al/PTFE at different heating rates was analyzed by simultaneous thermal analysis (TG-DSC). The results show that the thickness of the oxide layer has a significant effect on the reaction process of Al/PTFE. In the system with an oxide layer thickness of 5 Å, the compactness of the oxide layer changes due to thermal rearrangement, resulting in the diffusion of reactants (fluorine-containing substances) through the oxide layer into the Al core. The reaction mainly occurs between the oxide layer and the Al core. For the 10 Å oxide layer, the reaction only exists outside the interface of the oxide layer. With the movement of the oxygen ions in the oxide layer and the Al atoms in the Al core, the oxide layer moves to the Al core, which makes the reaction continue. By analyzing the reaction process of Al/PTFE, the mechanism function of Al/PTFE was obtained by combining the shrinkage volume model (R3 model) and the three-dimensional diffusion (D3 model). In addition, the activation energy of Al/PTFE was 258.8 kJ/mol and the pre-exponential factor was 2.495 × 1015 min−1. The research results have important theoretical significance and reference value for the in-depth understanding of the microscopic chemical reaction mechanism and the quantitative study of macroscopic energy release of Al/PTFE reactive materials.