Available Technologies

Background

CrCoNi-based medium-entropy alloys (MEAs) possess high toughness while also exhibiting exceptionally high strength among both high-entropy alloys (HEAs) and MEAs, making them suitable for use in sliding components.
However, due to differences in the redox potentials of their constituent elements, multicomponent alloys are generally considered difficult to deposit as thin films with equiatomic composition by electroplating. In particular, when Cr is included as a constituent element, there is a challenge in that a complex deposition process must be employed, partly due to environmental considerations.

Description and Advantages

Kyoto University researchers have successfully formed thin films of medium-entropy alloys with nearly equiatomic composition by optimizing the electroplating solution and conditions.

✓　High Flexibility in the Selection of Constituent Elements

       This technology enables electroplating on MEAs containing Cr. Furthermore, in principle, any combination of elements that can be  reduced in an aqueous solution is possible.

✓　Equiatomic ratio adjustment of constituent elements　

      The surface morphology of the thin film obtained by the new electroplating method is relatively smooth, and the constituent elements can be deposited in nearly equiatomic ratios (Fig.1 &.2).

✓　Rapid Fabrication of MEA Thin Films　

        By mixing multiple types of solvents in appropriate ratios in the electroplating solution, multiple types of metal ions can be continuously supplied to the electrode during electroplating, enabling rapid fabrication of MEA thin films.