  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.
