To explore the shock wave initiation capacity of typical energetic materials, an improved gap test is used to study the critical shock wave initiation pressure of three typical energetic materials, including RDX-based mixed explosives, HMXbased mixed explosives, and RDX/AP/Al-based mixed explosives. The equivalent contrast of the critical initiation capacity of typical energetic materials with TNT is conducted. The results show that the equivalent ratios of the critical initiation pressure of TNT for RDX-based and HMX-based mixed explosives are less than 1, which means that their shock wave sensitivity and initiation capacity are higher than TNT. However, the shock wave initiation capacity of RDX/AP/Al-based propellant mixed explosive is not up to that of TNT. In addition, to further clarify the dynamic change of the shock initiation process, the shock wave initiation of the RDX-based mixture is selected to perform a numerical simulation. The results show that when the pressure is greater than the critical pressure, a detonation growth process to achieve complete detonation is experienced after the shock wave passes through the gaps and enters the explosive. Therefore, the research results can provide basic data for the critical shock wave initiation capacity of energetic materials.

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To study the effects of composition on the thermal decomposition of emulsion explosives (EE), the methods of C80 micro calorimeter were used to attain the data of the thermal dynamic behavior. Based on the C80 data curve, the decomposition characteristics of EE with different components were researched by the nonlinear fitting kinetic method. The results show that the addition of urea reduces the thermal stability of EE and significantly improves its heat release. Its safety needs to be paid attention to temperature control and thermal safety measures.

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Electrolytic ignition systems are expected to be compatible with ammonium dinitramide (ADN)-based propellants, but it is necessary to understand the associated electrolysis mechanisms when developing such systems. The present study analyzed the electrolysis of molten ADN, employing a specially designed apparatus, while examining the various products using in situ microscopy, Raman spectroscopy, ion chromatography, gas detector tubes and Fourier transform infrared (FTIR) spectroscopy. During electrolysis, the formation of numerous bubbles was observed, and the color of molten ADN changed from yellow to pale yellow with the progress of electrolysis. Raman spectra and ion chromatogram confirmed the presence of nitrate ion in the resulting residue, while a gas detector tube indicated that gaseous nitrogen dioxide (NO₂) and ammonia were generated. FT-IR spectra demonstrated that N₂O and water present in the gaseous products. Using these results, a new mechanism for the processes occurring during the electrolysis of molten ADN was devised. The findings reported herein provide an improved understanding of the electrolysis mechanism of ADN-based propellants.

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Fast Cook-off test (FCO), based on STANAG 4240 Ed2 test procedures 1 and 2, is using liquid hydrocarbon fuels (LHF) to simulate the scenario of fire accidents. However, recently due to increasingly concerning environmental protection, economic effectiveness, and technique enhancement, NATO adopted a new standard AOP 4240 instead of STANAG Ed2 in 2018 for international test standards, which adds procedure 3 using a gas-fueled (GF) heating source for simulation of realistic fire scenarios. By comparison of the most recent global measures applied and in compliance with AOP 4240 requirements, this paper proposes the eco-friendly and safe FCO solution combining the modular-designed burner system with fail-safe propane systems to simulate the fire scenario effectively. Additionally, utilizing the costeffective and flexible devices separately to collect experimental data. This approach can guarantee test validity and provide more benefits than the traditional test method.

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This paper reports the development of a laser ignition system for a super-small solid rocket motor to be used in the OMOTENASHI, a 6U-CubeSat that is the smallest lunar lander ever. A safe, compact, lightweight, and optimized system using a laser diode was developed to ignite the rocket motor. The development was successful, and the spacecraft equipped with the laser ignition system was delivered to NASA. The laser ignition system will be the first one for a spacecraft going on a deep space exploration.

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