Ammonium DiNitramide (ADN) is an interesting oxidizer to replace ammonium perchlorate in the composition of solid propellants. In this study, Spray Flash Evaporation (SFE) is presented as a new technology to enhance stability of ADN by crystallization of nanoparticles. The crystallinity and purity of the compound was confirmed by X‐Ray Diffraction and Raman analysis. An average diameter of spherical particles around 32 nm (solution of ethyl acetate) and 34 nm (solution of methyl acetate) was measured by Scanning Electronic Microscopy (SEM). Furthermore, the downsizing to nanoscale induces a slower moisture absorption kinetic under 55 % of relative humidity, a reduction of the critical diameter of detonation and the desensitization to impact.

To our knowledge, the incorporation of nanodiamond (nD) as a reducing agent in an energetic composition has never been reported in the literature. Diamond exhibits particularly interesting physico‐chemical properties: high density, good energetic potential, and relatively low thermal sensitivity. This study proposes to demonstrate that an explosive energetic composition can be obtained by physical mixing of nD and potassium chlorate (PC). First, the energetic characteristics of this formulation were compared to those of the famous “white powder” made of PC and saccharose and discovered by the French chemist Berthollet in the 18th century. In the second part, the combustion of pelletized nD‐based mixtures initiated by a laser beam was studied by time resolved cinematography. The deflagration velocity was measured on the most energetic composition, which has a slightly negative oxygen balance (OB=−30.1%).

Thermites prepared from nanoparticles are currently the subject of growing interest due to their increased performances compared to classical micrometer‐sized thermites. Here, we studied the combustion behavior of energetic composite composed of Al and chromium (III) oxide (Cr2O3) as function of the oxide particle size. Homogeneous composites were prepared by mixing Al nanoparticles (Φ≈50 nm) with Cr2O3 micro‐ and nanoparticles (Φ≈20 nm), respectively, in hexane solution. The dried Cr2O3/Al composite powders were ignited by using a CO2 laser beam. The use of nanosized Cr2O3 particles incontestably improves the energetic performances of the Al/Cr2O3 thermite since the ignition delay time was shortened by a factor 3.5 (16±2 vs 54±4 ms) and the combustion rate (340±10 mm s−1) was significantly accelerated in contrast to those reported until now. Interestingly, the sensitivity to friction of the Al‐based thermites formulated from Cr2O3 is two orders of magnitude lower than the thermite prepared from other metal oxide nanoparticles (MnO2, WO3). Finally, our study shows that the decrease of Cr2O3 particle size has an interesting and beneficial effect on the energetic properties of Cr2O3/Al thermites and appears as an alternative to tune the properties of these energetic materials.

Section 3.3.1 First Paragraph second sentence:As can be observed, the thermite made of micro-Cr 2 O 3 is much more sensitive to impact than its nano-Cr 2 O 3 counterpart, the sensitivity being however relatively low compared to the one of commonly used organic explosives such as hexogen or octogen.should be read:As can be observed, the thermite made of micro-Cr 2 O 3 is much less sensitive to impact than its nano-Cr 2 O 3 counterpart, the sensitivity being however relatively low compared to the one of commonly used organic explosives such as hexogen or octogen.88