Abstract
In this work, the precipitation sequence in different Al-alloys containing Si, Mg and/or Cu as major alloying elements is investigated by differential scanning calorimetry (DSC) and dilatometric tests. The superposed exothermic and endothermal effects due to the precipitation and dissolution of Si are separated by the temperature dependence of the instantaneous coefficient of thermal expansion (CTE) from the precipitation sequence of θ’/θ and β precipitates of the age hardening elements. Vacancy annihilation during heating of quenched samples can only be observed by dilatometry of the Si-free alloys.

Key words
Al-alloys, precipitation kinetics, thermal expansion, differential scanning calorimetry (DSC), dilatometry

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