Aluminium Nanoflakes for Propulsion Application – ANPA

Energetic materials play a key role in many applications both civilian and military. The objective of the ANPA project is to synthesize, characterize and understand the mechanisms of oxidation of nanostructured aluminum powders with the aim of their application in the formulation of propellants. Based on our recent results, unexpected in view of what is generally accepted by the scientific community, we plan to optimize procedures of high-energy mechanical milling in order to produce aluminum nanopowders with high specific areas and optimal morphology for improved reactivity in solid and hybrid propulsion applications. This reactivity will be tested at two levels. Firstly, thermogravimetry analyses in the presence of oxygen will be performed and a first study based on the optimization of the milling additives will allow defining optimized samples. Secondly, elaborated powders will be formulated in propellants and tested in ballistic experiments in order to compare them with the best existing products. Meanwhile, a fundamental study of the oxidation mechanisms of aluminum powders will be conducted to understand the influence on reactivity of dimensional, morphological, nanostructural parameters and of local chemistry. The oxidation of aluminum particles is a complex phenomenon that involves both phase transitions and chemical reactions in a confined system. The most refined methods of chemical analysis, thermodynamics, kinetics, structural analysis and imaging will be used to propose the most likely reaction scenario. This fundamental study will contribute to define the optimum for the intended application but also to improve the knowledge in the field of the reactivity of materials either nanostructured and / or having a high surface area. The project deliverables are of both applied and fundamental nature. At the end of the project we want to propose a new process for the synthesis of aluminum nanopowders that can be used in propellant for solid and hybrid propulsion. The partners associated, with ONERA, will deposit a patent covering the whole process of fabrication and formulation of the aluminum nanopowders. Moreover the partners will publish in high impact research journal their fundamental results, interpretations and models of the oxidation of aluminum nanopowders.