Formation of Al oxide particles in combustion of aluminized condensed systems

The experimental methods used for characterization of oxide particles formed in combustion of Al containing model solid propellants and pyrotechnic mixtures are briefly discussed. The size distribution and chemical composition of the combustion products are determined using aluminized condensed systems of different formulations burning under atmospheric and elevated pressures. Agglomeration of original Al particles on the propellant burning surface is studied in dependency on the pressure and component composition. The combustion completeness of Al is studied for different propellants and combustion conditions. The burning law of individual Al particles and the fraction of oxide accumulated on the burning particle surface are determined. Recommendations on reducing the Al agglomeration extent are discussed. Formation of nano oxide particles is studied when varying the size of mother Al particle in the range of 10 - 500 micron. The initial nanoparticles compose tens of micron aggregates with fractal-like dimension about 1.6. The aggregates have the electrical charge about few elementary positive or negative electric units.