Multiscale modelling of hardening precipitate interfaces in alloy design

The project will establish a multiscale model for theoretical determination of precipitation hardening effects in metal alloys, using an industrial Al-Mg-Si alloy as the test case. This can only be achieved through first principle based multiscale modelli ng schemes, since the material properties are determined by the physics at various length scales, from atomistic to the macroscopic scale. To the knowledge of the applicants, no such scheme has been fully established at this stage. The project will hire a postdoc at NTNU working on atomistic modelling, in close collaboration with two research groups in SINTEF, focusing on finite element modelling and classical mean-field models, respectively. The modelling scheme will be validated by Hydro Aluminium, as an industrial partner. For the atomistic studies, the present project will merge a new density functional theory based scheme for modelling extended regions on the interface with a finite element modelling based scheme for deriving the long range preci pitate induced strain field in the matrix. In this manner, with extension to modelling of the entire interface, the required input for the mean-field modelling is obtained. The mean-field model tracks the evolution of the entire precipitate size distribut ion from which many important properties can be derived. It has previously been used for the Al-Mg-Si alloy system, but will reformulated in order make use of the atomistic input. Considering the increasing demand from the metal industry for tailoring ma terials properties, this community is expected to significantly benefit from the multiscale model, with theoretical optimization predictions being both more reliable and achieved faster, compared to current day standards. The project treats important indu strial problems with computational need and requires significant computation time through the Norwegian high performance computing facilities.