Since the early 20th century, lead azide (LA) has been commonly used as a primary explosive. However, lead pollution in the air and soil has attracted more and more attention, particularly in military training grounds and shooting ranges. Copper(I) 5-nitrotetrazolate (DBX-1) is considered as one of the most promising alternatives to LA. DBX-1 is typically prepared from sodium 5-nitrotetrazolate dihydrate [NaNT(H 2 O) 2 ] and copper(I) chloride (CuCl). But little is known about its optimal synthesis parameters. In addition, NaNT(H 2 O) 2 is not commercially available. In this study, NaNT(H 2 O) 2 was prepared by ourselves. Taguchi's experimental design method was used to determine the optimal experimental conditions for obtaining the maximum yield of DBX-1. The synthesized NaNT(H 2 O) 2 and DBX-1 were identified by means of SEM, NMR, FTIR, EA, UV-Vis and STA TG-DSC, and the sensitivity of DBX-1 was determined using BAM fallhammer, BAM friction tester and electrostatic spark sensitivity tester. The experimental results indicated that the optimal synthesis parameters of DBX-1 were as follows: the reaction temperature was 100°C, the reaction time was 30 min, the concentration of NaNT(H 2 O) 2 was 0.075 wt.% and the molar ratio of NaNT(H 2 O) 2 to CuCl was 1.15, and then the maximum yield after purification could reach 72.2 %. The decomposition activation energies of DBX-1 calculated by Kissinger and Ozawa methods were 178.6 and 179.0 kJ/mol, respectively. In addition, the impact sensitivity, friction sensitivity and electrostatic spark sensitivity of DBX-1 were 51 mJ, 0.4 N and 7.3 mJ, respectively, which were almost the same as those for LA.

Traditional primary explosives are usually heavy metal salts, especially salts of lead, such as lead azide (LA) and lead styphnate (LS), which can cause environmental pollution problems. The potassium salt of 4,6‐dinitrobenzofuroxan (KDNBF) has attracted more and more attention due to its advantages of no heavy metal pollution to the environment and appropriate sensitivity. There are many reports on the thermal properties and applications of KDNBF, but few reports on the morphological properties. In addition, little is known about the optimal synthesis conditions of KDNBF with different morphologies in the preparation process. In this study, Taguchi's experimental design method was used to determine the optimal experimental conditions for obtaining the maximum yields of KDNBF with different morphologies. The synthesized KDNBF was identified by means of SEM, NMR, FTIR, EA, and TG‐DSC, and its sensitivity was measured using BAM fallhammer, BAM friction tester, and electrostatic spark sensitivity tester. The experimental results indicated that the maximum yields of flaky and spherical KDNBFs could reach 85.6 % and 82.6 % after purification under the optimal experimental condition, respectively. The spherical KDNBF powder had a relatively denser structure than the flaky KDNBF powder. The thermal analyses showed that the activation energies of the decomposition reaction of the flaky and spherical KDNBF powders calculated by the Kissinger method were 171.5 and 188.5 kJ mol−1, respectively, and the Ozawa method were 170.7 and 186.9 kJ mol−1, respectively. The thermal stability of spherical KDNBF powder was higher than that of flaky KDNBF powder. In addition, the sensitivity tests showed that the spherical KDNBF powder was less sensitive than the flaky KDNBF powder.

Four series of TNT based melt cast explosives were prepared by mixing RDX, CL‐20, FOX‐7, and TKX‐50 with TNT in different mass ratios. The compatibility of these composition explosives was evaluated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) according to the STANAG 4147 standard. Furthermore, the DSC and TGA data were also used to calculate the activation energies by the Kissinger and Ozawa methods. The experimental results indicated that the TNT/FOX‐7 composition explosives had good compatibility, whereas the TNT/CL‐20 composition explosives had poor compatibility. The TNT/RDX and TNT/TKX‐50 composition explosives at the mass ratios of 50 : 50, 40 : 60, 30 : 70, 20 : 80 and 10 : 90 had good compatibility. Furthermore, the decomposition activation energy of TNT/FOX‐7 composition explosives increased with increasing FOX‐7 content. Under the compatible condition, the decomposition activation energy of TNT/RDX composition explosives also increased with increasing RDX content, but the decomposition activation energy of TNT/TKX‐50 composition explosives decreased with increasing TKX‐50 content.

In this study, the solventing‐out recrystallization method was applied to prepare insensitive and spherical high bulk density nitroguanidine (NQ). Experiments were performed at various operating conditions by using N‐methyl‐pyrrolidone (NMP) and acetone as solvent and antisolvent, respectively. The effects of different operating parameters such as NQ/NMP ratio, amount of acetone used, crystallization temperature, stirring speed and stirring time were investigated. The particle size and morphology of the prepared NQ crystals were observed by scanning electron microscopy (SEM), the bulk density was measured by the Archimedes’ method and the impact sensitivity was determined by fall hammer method. The experimental results showed that the solventing‐out recrystallization method could be used to prepare spherical high bulk density NQ with a narrow particle size distribution and the particle size could be controlled by changing the operating conditions. The bulk density of these spherical NQ particles was found to be in the range of 0.94–0.97 g cm−3, which is higher than that of needle‐shaped NQ particles, and they became less sensitive towards impact.