Accelerated artificial ageing regimes of commercial aluminium alloys. II: Al-Cu, Al-Zn-Mg-(Cu), Al-Mg-Si-(Cu) alloys

For Al-Cu, Al-Zn-Mg-(Cu), Al-Mg-Si-(Cu) commercial aluminium alloys effects of temperature and exposure on the phase composition and morphology of hardener precipitates, strength and plasticity were carried out. These results are submitted as TTT (time-temperature-transformation) and TTP (time-temperature-properties) diagrams for ageing. For acceleration of ageing the two-stage ageing regimes with high-temperature stages are used, the characteristics hardener precipitates remaining close to optimum. The examples of the accelerated ageing regimes in industrial conditions for sheets from 1201 alloy (type of 2219), sheets from V95 alloy (type of 7075), forgings from AK6 alloy (system Al-Mg-Si-Cu) are presented. The comparison of the mechanical properties, damage tolerance, corrosion resistance of the semi-products processed by standard and accelerated regimes is given. (C) 2000 Elsevier Science S.A. All rights reserved.