High hardness Ta doped eutectic high entropy alloy by wire arc additive manufacturing

Integrating Wire Arc Additive Manufacturing (WAAM) with HEAs presents numerous advantages, notably cost-effectively and efficiently producing large-scale components. However, the successful implementation of WAAM for HEAs necessitates specific filament compositions, which poses challenges. While softer HEAs like Canrtor can be manufactured using solid wire or multicomponent wire cords, fabricating solid wire with the requisite composition for high-hardness alloys becomes unfeasible. Addressing this technological complexity is the focus of this study. The proposed methodology revolves around gas metal arc welding (GMAW), which employs metal powdercored wires (MPCW). These wires contain powder components in equal proportions, offering advantages over alternative bulk alloy production methods such as vacuum or argon-plasma melting, primarily due to the greater volume of molten material within the workpiece. The refinement of this approach is illustrated using a high-hardness eutectic high-entropy FeCoNiAl alloy system doped with Ta. The resulting WAAMed alloy initially exhibits nearly zero plasticity, a characteristic later mitigated through a specialized heat treatment procedure.