The effects of room temperature ECAP and subsequent aging on mechanical properties of 2024 Al alloy

Mechanical properties of the 2024 aluminum alloy, which was plastically deformed by equal channel angular pressing (ECAP) at room temperature and aged naturally and artificially at 70 degrees C and 100 degrees C for different times, were investigated in this research. Many of the short shear bands were observed on the microstructure after one pass of ECAP and led to fragmentation of grains. Hardness and yield stress of the sample aged naturally after deformation were considerably improved due to increase of dislocation density calculated by XRD data analysis and their interaction with solute atoms during ECAP. The ductility and work hardening exponent of the deformed samples were significantly reduced due to formation of shear bands within the microstructure. However aging the samples immediately after sever plastic deformation at 70 degrees C and 100 degrees C caused an additional improvement in hardness and yield stress relative to the samples aged naturally after deformation. (C) 2013 Elsevier B. V. All rights reserved.