Superfunctional materials by ultra-severe plastic deformation

TL;DR

This paper reviews how ultra-severe plastic deformation (ultra-SPD) techniques enable the creation of superfunctional materials with enhanced properties like superplasticity, superconductivity, and photocatalytic activity, opening new avenues in material science.

Contribution

It introduces the concept of ultra-SPD and discusses its application in synthesizing novel superfunctional materials with superior properties.

Findings

High-temperature stability in new aluminum alloys

Room-temperature superplasticity in magnesium and aluminum alloys

Superconductivity and high strength in Nb-Ti alloys

Abstract

Superfunctional materials are defined as materials with specific properties being superior to the functions of engineering materials. Numerous studies introduced severe plastic deformation (SPD) as an effective process to improve the functional and mechanical properties of various metallic and non-metallic materials. Moreover, the concept of ultra-SPD - introducing shear strains over 1000 to reduce the thickness of sheared phases to levels comparable to atomic distances - was recently utilized to synthesize novel superfunctional materials. In this article, the application of ultra-SPD for controlling atomic diffusion and phase transformation and synthesizing new materials with superfunctional properties is discussed. The main properties achieved by ultra-SPD include: (i) high-temperature thermal stability in new immiscible age-hardenable aluminum alloys; (ii) room-temperature superplasticity for the first time in magnesium and aluminum alloys; (iii) high strength and high plasticity in nanograined intermetallics; (iv) low elastic modulus and high hardness in biocompatible binary and high-entropy alloys; (v) superconductivity and high strength in the Nb-Ti alloys; (vi) room-temperature hydrogen storage for the first time in magnesium alloys; and (vii) superior photocatalytic hydrogen production, oxygen production, and carbon dioxide conversion on high-entropy oxides and oxynitrides as a new family of photocatalysts.