Materials Science Forum, Vol.503-504, 585-590, 2006
The influence of the SPD temperature on superplasticity of aluminium alloys
Recent studies have demonstrated that ultrafine-grained (UFG) alloys processed by equal channel angular pressing (ECAP) and high pressure torsion (HPT) can exhibit enhanced superplacticity at relatively low temperature and/or high strain rates. At the same time severe plastic deformation (SPD) of aluminium alloys is often carried out at elevated temperatures leading to various grain size and volume fraction of precipitates. The significance of the SPD temperature for commercial 1420 and 1421 aluminium alloys has been evaluated in this paper using in-situ heating of thin foils in the column of a transmission electron microscope. Superplastic characteristics of alloys processed at various ECAP temperatures are discussed.