Shear-spinning-tailored dislocation substructures driving dislocation–precipitation synergistic strengthening in a Fe₄₀Ni₃₆Al₁₃Cr₁₀Mo₁ hypoeutectic dual-phase high-entropy alloy

Shear spinning is proposed as an industrially scalable route to engineer gradient dislocation architectures in the Fe₄₀Ni₃₆Al₁₃Cr₁₀Mo₁ hypoeutectic dual-phase high-entropy alloy (DP-HEA), addressing the longstanding challenge of introducing high-density, non-uniform dislocation structures at engineering-relevant scales. The unique triaxial stress state activates multiple non-coplanar slip systems, generating a three-dimensional cellular dislocation network in the FCC matrix at a density of 4.54 × 10 ¹ ⁵ m⁻², which is ∼15% higher than that produced by conventional cold rolling (3.93 × 10 ¹⁵ m⁻²). This high-energy defect state accelerates co-precipitation of coherent L1₂ and B2 phases during aging, with L1₂ contributing ∼20% to the total yield strength versus ∼15% in the cold-rolled-and-aged counterpart. The shear-spun-and-aged alloy achieves a yield strength of 1283 MPa, an ultimate tensile strength of 1512 MPa, and a tensile elongation of 8.2%, representing a ∼61% enhancement over the solution-treated state and ∼56 MPa above the cold-rolled-and-aged condition. A fundamental mechanistic transition from dislocation hardening (∼900 MPa) in the as-spun state to synergistic dislocation–precipitation strengthening after aging demonstrates shear spinning as a practical industrial strategy for concurrently tailoring dislocation configurations and precipitation kinetics to overcome the strength–ductility trade-off in multiphase HEAs.