Intermediate temperature creep behaviour of a forged Al–Cu–Mg–Si–Mn alloy

The creep behaviour of an Al–4.4Cu–0.5Mg–0.9Si–0.8Mn alloy (IADS 2014 grade, numbers indicate wt.%) was experimentally investigated in the temperature range from 403 to 443 K for relatively long time (up to 5000 h). The material was sampled in axial direction from a cylindrical forged component in the T6 temper condition. The exposure at test temperature caused reduction in hardness up to 20%. The deformation behaviour of the alloy (secondary creep strain rate) in power-law and power-law breakdown regimes was modelled considering the presence of an apparent threshold stress, this latter decreasing with time due to the coarsening of strengthening particles.