Effects of strain path on the microstructure of aluminum alloys during Equal Channel Angular Pressing (ECAP)

Abstract

Aluminum alloys AA1050 and AA6061 were processed by ECAP following either monotonic or redundant routes. The materials were characterized by optical microscopy and orientation imaging microscopy. Grain shape changes were analyzed in different billet planes to assess microstructure refinement mechanisms and were consistent with a proposed model. The results demonstrate that microstructure development is not independent of processing route. In the case of AA6061, annealing characteristics were examined to determine if the material has the requisite properties typically exhibited by a superplastic material. Recommendations are made for future research. This work was funded in part by the Air Force Office of Scientific Research (AFOSR) under contract number F1ATA06058G001.