Intermetallics formed at interface of ultrafine grained Al/Mg bi-layered disks processed by high pressure torsion at room temperature

摘要

In this work, Mg/Al bi-layered disks were fabricated by high pressure torsion (HPT) at room temperature. A 0.26 mu m layer of gamma-Mg17Al12 intermetallic formed at the interface of Mg/Al disks. This is very different to the interface of Mg/Al produced by other techniques such as diffusion bonding and friction stir welding where both gamma-Mg17Al12 and beta-Al3Mg2 form and the beta-Al3Mg2 layer is much thicker than the gamma-Mg17Al12 layer. This unusual phenomenon is attributed to the interfacial energies of intermetallics and the effect of room temperature HPT on diffusion of Al in Mg and they gamma-Mg17Al12 layer. (C) 2016 Elsevier B.V. All rights reserved.