Influence of Strain Reversals during High Pressure Torsion Process on Strengthening in Al-Cu-Mg(-Li) Alloy
The strengthening of AlCuMg(Li) alloys subjected to high pressure torsion (HPT) deformation with strain reversals was studied by microhardness (Hv) tests and differential scanning calorimetry (DSC). It was found that the strengthening is lower for both cyclic HPT (c-HPT) and single reversal HPT (sr-HPT) as compared to monotonic HPT (m-HPT). The DSC results demonstrate that |HPT influences S phase precipitation. With increasing strain, the maximum heat flow (height of the S peak) and the heat content of S formation peaks increases. There is a larger S heat content reaction in the periphery of HPT processed disks compared with those in the centre. Strain reversal also has a significant influence on the S precipitation. The strengthening during HPT deformation is discussed in terms of the density of statistically stored and geometrically necessary dislocations.
Jing Tao Wang, Roberto B. Figueiredo and Terence G. Langdon
J. W. Zhang et al., "Influence of Strain Reversals during High Pressure Torsion Process on Strengthening in Al-Cu-Mg(-Li) Alloy", Materials Science Forum, Vols. 667-669, pp. 809-814, 2011