High-entropy alloys: a critical assessment of their founding principles and future prospects

High-entropy alloys (HEAs) are a relatively new class of materials that have gained considerable attention from the metallurgical research community over recent years. They are characterised by their unconventional compositions, in that they are not based around a single major component, but rather comprise multiple principal alloying elements. Four core effects have been proposed in HEAs: (i) the entropic stabilisation of solid solutions, (ii) the severe distortion of their lattices, (iii) sluggish diffusion kinetics, and (iv) that properties are derived from a cocktail effect. By assessing these claims on the basis of existing experimental evidence in the literature, as well as classical metallurgical…

• EA
  Engineering and Physical Sciences Research Council

  Awards: EP/H500375/1, EP/M005607/1