Kinetics of oxidation of metal nanoparticles acquired practical importance with rapidly developing nanoenergetic systems and materials. Nanoenergetic thermites include mixtures of Al and metal oxides in nanoscale. Our research focuses on modeling aluminum combustion in nanoscale. The research problem is considered a spherically symmetric case and used the Cabrera Mott oxidation model to describe the kinetics of oxide growth on the aluminum nanoparticles to predict reaction temperature, thermal front velocity and oxidation time. We assumed that aluminum of radius 10 to 50 nm is covered by a thin oxide layer (1-4nm) and is surrounded by abundant amount of oxygen stored by oxidizers. The ball is rapidly heated up to ignition temperature to initiate self-sustaining oxidation reaction as a result of highly exothermic reaction. We investigated oxidation model numerically, using the COMSOL software. The software runs the finite element analysis along with the grid takes into account the geometric configuration of the body. In the oxide layer of excess concentrations of electrons and ions are dependent on the electric field potential with the corresponding of the Gibbs factors and that it conducts to the solution of a nonlinear Poisson equation for the electric field potential in a moving boundary domain.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2013: Electronics, Devices, Fabrication, MEMS, Fluidics and Computational (Volume 2)
Published: May 12, 2013
Pages: 587 - 590
Industry sector: Advanced Materials & Manufacturing
Topics: Informatics, Modeling & Simulation