Role of vacancies during creep and secondary precipitation in an underaged Al-Cu-Mg-Ag alloy



Aluminium alloys that are deliberately underaged show both enhanced creep resistance at elevated temperatures and high responses to secondary ageing at lower temperatures (e.g. 20-65 °C). These phenomena appear to be strongly influenced by the presence of vacant lattice sites and positron annihilation spectroscopy has been used to study the roles of solute/vacancy interaction during precipitation in an aged Al-Cu-Mg-Ag alloy. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)