Effect of heat treatment on AA2014 alloy processed through multi-pass friction stir processing

Abstract

In this paper, the ultrafine grain (UFG) structure was prepared in AA2014 via multipass friction stir processing (FSP). Post-processing heat treatment was carried out in order to enhance the mechanical properties. For achieving this aim, trail experiments have been performed to opt the process parameters and number of passes. 3D optical microscopy, Vickers's microhardness tester, and universal tensile testing (UTM) machine were employed to study the microstructural features and mechanical properties and the results have been reported. Scanning electron microscope (SEM) was used to examine the microstructures of fracture features of tensile specimens. The properties of the heat treated (HT) sample was found better than the non-heat treated (NHT) sample. Fracture surfaces of both samples show the presence of large dimples which indicates ductile failure.