High Entropy Alloys for Energy Conversion and Storage: A Review of Grain Boundary Wetting Phenomena

The multicomponent alloys with nearly equal concentration of components, also known as high entropy (HEAs), were first proposed 22 years ago. HEAs quickly became very important in materials science due to their unique properties. Nowadays, the are frequently used energy conversion and storage applications. can consist five, six or more components. Plasma cladding permits coating large surfaces cheap substrates (often expensive) enlarge, such a way, application area. large-area coatings deposited by plasma possess multiple advantages low thermal distortion, density, well dilution substrate material. ensures good metallurgical bonding between substrate. costs operation equipment attractive. During cladding, mixed powders blown carrier gas into torch positioned on This powder mixture is then melted under torch. torch, turn, sequentially scans After finalizing crystallization process, solid polycrystal appears which contains few residual melts. remaining melt completely incompletely wet grain boundaries (GBs) phase polycrystal. These wetted GBs strongly influence microstructure HEA morphology. In this review we analyze GB wetting containing one two, three phases, reinforced particles carbides, nitrides, borides, oxides. We rather thick after additional laser remelting observe how changes over thickness.