Study of precipitates formation in Al‐4.5Wt%Cu and Al‐4.5Wt%Cu‐0.1Wt%In alloys using creep measurements and positron annihilation technique

The transient and steady state creep deformation of Al‐4.5 wt%Cu and Al‐4.5 wt%Cu‐0.1 wt%In alloys were studied using a constant stress in the aging temperatures range 403 to 703 K for various aging times under different working temperatures. Positron annihilation studies using Doppler–broadening measurements were carried out on the specimens used in creep measurements. The subsequent decrease and increase in the creep parameters n, β and ε_st as well as in Doppler lineshape parameter with increasing aging temperatures and aging times were explained on the basis of structure transformations occuring in Al‐Cu alloys. The mechanical creep measurements are very well correlated with positron annihilation characteristics. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)