Ultra-severe plastic deformation for room-temperature superplasticity and superfunctionality

Abstract

Abstract. Ultra-severe plastic deformation (ulta-SPD) is a terminology used for the introduction of extremely large shear strains (over 1000) to material so that the thickness of sheared phases geometrically reaches the subnanometer level. Under such extreme shearing conditions, new nanostructured phases with unique properties are formed even from the immiscible systems. Various metallic alloys and ceramics were developed by this concept for different applications such as room-temperature superplasticity, room-temperature hydrogen storage, photocatalytic hydrogen production, photocatalytic carbon dioxide conversion, etc. This article reviews recent advances regarding ultra-SPD with a focus on low-temperature superplasticity, which was reported for the first time at room temperature in aluminum and magnesium alloys.