1D steady-state finite-element modelling of a bi-carrier one-layer oxide film

Many engineering materials rely on an oxide film to protect them from uniform corrosion. The compact part of this film is commonly modelled using point defect and mixed conduction type models. An extension for use with these models, i.e. the implementation of Poisson’s equation, has been investigated for a bi-carrier one-layer oxide film. The simultaneous set of partial differential equations – two mass transport equations and the Poisson equation – have been solved using finite-elements. The extended model allows to confirm some, but not all, assumptions commonly associated with point defect and mixed conduction type models.