MedeA Application Notes for Aerospace

Interfaces are present in most materials and have a large impact on mechanical properties such as stiffness and yield strength. Given that the properties of an interface can radically change by the presence of even minute amounts of impurities, it is of great interest to predict the effect of segregated atoms at interfaces.

As systematic experimental information on the impact of specific defect types on the grain boundary strength is hard to obtain, computational modelling is of great help.

Accurate measurements of diffusion coefficients of atoms in solids are difficult and deviations between different experiments can be several orders of magnitude. For the benchmark case of hydrogen diffusion in nickel first-principles calculations give a remarkable agreement with available experimental data especially near room temperature. Thus, computations of diffusion coefficients can be comparable in reliability with measured data. Simulations are possible for situations such as high strain, or slow processes where measurements are difficult or impractical.