General diffusion-kinetic model of metallic oxidation

Abstract A new mathematical diffusion-kinetic model of metallic oxidation under isothermal conditions is proposed. This model is used to define the universal kinetic equation to calculate the thickness of porous or dense oxide layer formed at a metal surface as function of oxidation time and several kinetic and equilibrium parameters describing longitudinal and lateral oxidant transfer. A block–slot model is adopted as a physical model of oxide layer. The universal kinetic equation describes various oxidation laws of type h(t) such as linear, parabolic and higher-order than parabolic, transition from one oxidation law to another and acceleration of oxidation, including sudden acceleration.