Hits:

Indexed by:会议论文

Date of Publication:2011-03-21

Included Journals:EI、CPCI-S、Scopus

Volume:667-669

Page Number:809-+

Key Words:aluminium alloy; high pressure torsion; strain reversal; differential scanning calorimetry

Abstract:The strengthening of Al-Cu-Mg(-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 vertical bar 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.