High-Throughput Design and Additive Manufacturing of Refractory MPEAs

Refractory multi-principal element alloys (MPEAs) are promising candidates for structural applications in extreme environments, but their implementation in additive manufacturing (AM) is challenged by composition-dependent phase formation and poor manufacturability. This work presents a high-throughput alloy design and manufacturing combining computational screening and experimental validation to identify ternary MPEAs within the Hf-Mo-Nb-Ta-Ti-Zr system with 100% BCC phase above 1000 °C, narrow solidification ranges (ΔT < 50 °C), and low susceptibility to cracking for improved processability. Out of 3,421 simulated compositions, six were selected for arc melting and subsequent characterization. Among them, Nb25Ti20Zr55 and Hf45Nb30Ti25 demonstrated stable single-phase BCC microstructures and favorable thermal and mechanical behavior. Phase stability was validated by in situ high-temperature XRD and DSC, while nanoindentation and confirmed promising strength and ductility. Preliminary DED trials suggest promising laser processing, with initial results indicating the potential for ductile, crack-free deposition, refined microstructures, and limited elemental segregation. These findings support a pathway from computational alloy design to additive manufacturing, contributing to the development of refractory MPEAs for aerospace, energy, and high-temperature applications.