Macroscopic Shear Banding in an Aluminum-Based Alloy During Equal-Channel Angular Pressing

Abstract

ABSTRACTEqual-channel angular pressing is now recognized as an effective technique for fabricating materials with ultrafine structures. It is generally considered that the strain is homogeneously distributed in the materials after ECA pressing. The present investigation shows, however, that severe macroscopic shear band, which extends from bottom to top surface and slants to the longitudinal axis of specimen at an angle of about 45°, develops at regular intervals, with a high shear strain accommodation of about 3.7 within the band. Different families of macroscopic shear bands may cut across each other, and the total volume fraction of macroscopic shear bands may well surpass 50%.