High-entropy alloys (HEAs) represent a modern category of materials formed through a multi-component approach, wherein alloying elements are combined to create a supersaturated solid solution. HEAs typically consist of equal proportions of these elemts. Notably, these materials exhibit outstanding mechanical characteristics, including high strength, ductility, corrosion resistance, and wear resistance.
Integrating Wire Arc Additive Manufacturing (WAAM) with High-Entropy Alloys (HEAs) presents numerous benefits. Foremost among these advantages is the ability to efficiently and cost-effectively produce large-scale components. To successfully implement WAAM for HEAs manufacturing, a crucial component is the presence of a filament with a specific chemical composition, such as a welding wire. While for softer HEAs like Cantor alloys, solid wire or multi-component wire cords can be utilized, the challenge arises with high-hardness alloys where fabricating a solid wire with the required composition becomes impractical. Addressing this intricate technological challenge forms the focal point of the current study [1].
The proposed method revolves around Gas Metal Arc Welding (GMAW) employing Metal Powder-Cored Wires (MPCW). These wires are filled with powder components in equal proportions to each other. This approach offers several advantages compared to alternative methods such as vacuum or argon-plasma melting, primarily due to its dominance in the molten volume of the workpiece. The evolution of this method is elaborated upon using a high-hardness eutectic high-entropy FeCoNiAl alloying system doped with Ta as a case study. The resulting WAAMed alloy exhibits nearly zero plasticity, a characteristic that becomes pronounced following a specialized heat treatment procedure.