Correlating Ten Composition-, Lattice- and Microstructure-Derived Descriptors with Compressive Yield Strength in Previously Reported Single-Phase BCC Refractory High-Entropy Alloys

Composition criteria for refractory high-entropy alloys (RHEAs) reliably predict whether a candidate composition forms a single-phase body-centred-cubic (BCC) solid solution, but not which BCC-confirmed composition will be strongest. Here we revisit seven previously reported RHEA compositions on freshly arc-melted material of our own, confirm each as single-phase BCC using full-spectrum X-ray diffraction re-indexing, and screen ten descriptors obtainable before mechanical testing against their room-temperature compressive yield strength: five compositional (mean atomic radius r−, mixing enthalpy ΔHmix, atomic-size mismatch δ, VEC, and melting point Tm), two lattice-scale (Nelson–Riley parameter a0 and Williamson–Hall apparent microstrain ε) and three microstructural (KAM, ELM15, and grain ECD). Only ΔHmix ranks the strengths, and its direction inverts the usual expectation: the less negative the mixing enthalpy, the stronger the alloy. Refractoriness carries no ranking information, and the most refractory member, NbMoTaW, is second weakest of six. At n = 6 only a perfect ranking reaches a Benjamini–Hochberg q below 0.05 across ten descriptors, so the q of 0.167 obtained here measures cohort resolution: a ranking of this magnitude clears the corrected threshold from eight alloys upwards. Mean atomic radius separately predicts a0 across all seven alloys.