Detailed Numerical Modeling and Simulation of Fe 2 O 3 −Al Thermite Reaction

Destructive Effect of High-Temperature Heat Flow of Solid Slow-Release Energetic Materials on a Steel Target

To investigate the high-temperature heat flow's destructive effect of solid slow-release energetic materials on a steel target, we prepared a sample of solid slow-release energetic materials, eruption devices, and a complete test system to conduct the destruction of high-temperature heat flow on the steel target. In addition, we proposed the energy density to characterise the high-temperature heat flow performance and numerically simulated the destructive effect of the high-temperature heat flow on the steel target. The numerical simulation results were in good agreement with the test results, and the error between them was under 8.5%. Based on the test and simulation results, the steady-state melting model of the steel target was established under the action of high-temperature heat flow. Moreover, a time-varying model of the melting hole shape was found. The results showed that the model of destroying the steel target with the high-temperature heat flow of solid slow-release energetic materials was highly accurate. Therefore, the model could provide theoretical guidance for designing and applying solid slow-release energetic materials in ammunition destruction, metal cutting, the simulation of the laser thermal effect, etc.

Thermite reaction driven pyrotechnic formulation with promising functional performance and reduced emissions

Green pyrotechnics/firecrackers reported herein are driven by thermite reactions for self-contained and self-sustained exothermic chemical reactions to make heat and sound by the usage of minimal fuel (aluminum), oxidizer (potassium nitrate), and Sulfur. These firecrackers have the potential for generating less emissions (70%) compared to commercial firecracker-based counterparts due to the presence of additives and are therefore designated as "Green firecrackers" or reduced emissions firecrackers. The functional performance and long-term stability of the composition was investigated through sound measurement and different tests, including ageing, thermal stability, and moisture test. The thermodynamics of the facilitated thermite reaction was cross-checked with experimental and theoretical methods. Prevalent mechanism for a substantial reduction in emissions to the tune of about 70% has been discussed. Cost of the green firecrackers is at par with the commercial firecrackers as cost of raw materials being used to prepare the formulation is comparable to the relatively toxic oxidizer substituted. "Green firecrackers" developed and reported here are environmentally benign in nature with higher business potential as far as a green chemistry-based sustainable solution for the society is required.

Chemical and Structural Analysis of Newly Prepared Co-W-Al Alloy by Aluminothermic Reaction

This article is devoted to the characterization of a new Co-W-Al alloy prepared by an aluminothermic reaction. This alloy is used for the subsequent preparation of a special composite nanopowder and for the surface coating of aluminum, magnesium, or iron alloys. Due to the very high temperature (2000 °C–3000 °C) required for the reaction, thermite was added to the mixture. Pulverized coal was also added in order to obtain the appropriate metal carbides (Co, W, Ti), which increase hardness, resistance to abrasion, and the corrosion of the coating and have good high temperature properties. The phase composition of the alloy prepared by the aluminothermic reaction showed mainly cobalt, tungsten, and aluminum, as well as small amounts of iron, titanium, and calcium. No carbon was identified using this method. The microstructure of this alloy is characterized by a cobalt matrix with smaller regular and irregular carbide particles doped by aluminum.