Computational Materials Science has grown rapidly over the last decades with remarkable close collaborations and long term partnerships between industry and academic researchers. In this work some examples of modelling subjects are presented to show the profitable commercial benefit resulting from the application of this type of research. The aspect of modelling is to connect theoretical and experimental work, having a sound theoretical base, which allows making predictions about distinguished material-s behaviour, for example prediction about precipitating evolution or mechanical properties. The major goal of the present work is the numerical description of the precipitation kinetics of Al-Mg-Si(-Cu) and Al-Zn-Mg(-Cu) alloys. Multiscale thermo-kinetic modelling is used for different aspects of processes, predicting the amounts of different phases as well as mechanical properties. Quantum mechanics modelling techniques are applied, describing materials properties such as enthalpy of formation of metastable and stable phases. Calculated ab intio binding energies enables to describe the interactions of elements and clusters to vacancies and the related influences to the mobility of the system are taken into account in the models.