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Pyrotechnic compositions using polyurethane as binder were designed to maximize the temperature of combustion and the burn rate. The flares consisted in mixtures of potassium perchlorate/Mg-Al alloy/polyurethane/additives. In order to determine the optimum input ratio that conducts to the most appropriate solution in terms of theoretical amount of heat released, specific volume of gaseous products and chemical composition, Explo5� thermochemical software runs were executed. Further, the temperature of combustion and the burn rate were determined by infrared thermography, while the heat of combustion and the specific volume of gases were obtained using an adiabatic calorimeter coupled with a Julius-Peters volumeter. The fuel ratio was varied in the compositions in order to optimize the combustion, and the addition of chlorinated rubber confirmed a significant enhancement in both parameters.

This paper presents the development, testing and evaluation of a new unguided rocket equipped with a thermobaric warhead. The aim of the research was to design the ammunition to be integrated with an existing multiple launch rocket system. This condition introduced limitations of dimensions, mass and mass distribution. The experimental work consisted also in optimisation of the thermobaric composition and configuration. The resulting ammunition was tested for determination of effective range and precision. The destructive effect was evaluated by live firing against non-armoured vehicles and masonry light structures.

The issue of heavy metal and radionuclide contamination is still causing a great deal of concern worldwide for environmental protection and industrial sites remediation. Various techniques have been developed for surface decontamination aiming for high decontamination factors (DF) and minimal environmental impact, but strippable polymeric nanocomposite coatings are some of the best candidates in this area. In this study, novel strippable coatings for heavy metal and radionuclides decontamination were developed based on the film-forming ability of polyvinyl alcohol, with the remarkable metal retention capacity of bentonite nanoclay, together with the chelating ability of sodium alginate and with “new-generation” “green” complexing agents: iminodisuccinic acid (IDS) and 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTC). These environmentally friendly water-based decontamination solutions are capable of generating strippable polymeric films with optimized mechanical and thermal properties while exhibiting high decontamination efficiency (DF ≈ 95–98% for heavy metals tested on glass surface and DF ≈ 91–97% for radionuclides 241Am, 90Sr-Y and 137Cs on metal, painted metal, plastic, and glass surfaces).

The objective of this research was to develop and to experimentally validate a method to predict the blast performance of thermobaric annular charges based on isopropyl nitrate‐aluminium and RDX‐isopropyl nitrate‐aluminium. Overpressure and thermal output were investigated in open air using piezoelectric pressure transducers, high speed visible and infrared imaging. Prediction of the explosive transformation of the annular thermobaric charge was computed by thermochemical code EXPLO5® using the Chapman‐Jouguet (ideal detonation) and non‐ideal Wood and Kirkwood (WK) detonation model. The Jones‐Wilkins‐Lee (JWL) parameters obtained in the calculations were used in hydrocode numerical simulation using AUTODYN® in order to predict the incident overpressure, total impulse and arrival time. Additional energy attributed to aluminium afterburning was used in order to simulate the post‐combustion phase. For isopropyl nitrate‐aluminium based charges, both BKW and WK models estimate correctly the peak overpressure and arrival time, while the total impulse was more accurately calculated by WK non‐ideal detonation model. For the RDX‐containing formulation, the prediction of peak overpressure, total impulse and arrival time are in agreement with the predictions obtained using WK non‐ideal detonation model with additional energy. The performances of the investigated thermobaric charges were compared with an equivalent mass charge of TNT, confirming both the expected higher total impulse and higher peak overpressures in the case of RDX‐isopropyl nitrate‐aluminium based thermobaric charges. Thermal measurements highlighted two distinct phases, an anaerobic phase and the post combustion of the thermobaric compositions. In terms of thermal output, the RDX‐isopropyl nitrate‐aluminium thermobaric based charge manifests superior performances.