Stable plastic deformability is crucial for the safe service and processing of refractory high-entropy alloys (RHEAs). However, localized planar-slip bands in these RHEAs are generally considered to promote strain localization and impair plasticity. Here, we present evidence for self-suppressed slip localization in Al7Nb34Ti34Zr25 RHEA. An initially localized planar-slip band does not remain continuously dominant, but undergoes repeated branching and activation of neighbouring slip pathways. Self-suppression denotes the interruption, rather than elimination, of persistent localization within the same dominant slip channel. This redistribution of slip activity is associated with strong pinning by chemical-order domains and accumulation of residual dislocation structures. This may locally obstruct repeated glide along the original band and favour participation of alternative pathways.
Mg-3Al-1Zn-0.3Mn alloy was fabricated by low-temperature extrusion to engineer a heterogeneous bimodal structure of coarse deformed grains and a fine dynamically recrystallized (DRXed) matrix. It exhibits a yield strength of 330 MPa, an ultimate tensile strength of 386 MPa, and a fatigue strength of 214 MPa at 107 cycles under R = 0, among the highest values reported for rare-earth-free Mg alloys. Mechanistic characterization reveals progressive participation of DRXed grains in cyclic deformation and activation of multiple dislocation slip modes, enabling distributed strain storage and accommodation. Meanwhile, the nearly fully-recrystallized counterpart shows localized basal slip and cleavage-dominated final fracture morphology.
Achieving yield strengths above 1000 MPa in copper alloys usually causes severe embrittlement, with elongation typically below 8%. Here, repulsive Cu-Cr immiscibility is exploited to redirect the phase separation pathway of a complex concentrated Cu-Ni-Mn-Al alloy. Adding 5 at.% Cr drives the formation of 3.4 nm Cr-rich nanoclusters and raises the L12-(Ni,Cu,Mn)3Al volume fraction from 25.2% to 32.9%, generating a three-dimensional interpenetrating nanocluster network. Both nanoclusters remain coherent and shearable. The alloy achieves a yield strength of 1020 ± 19 MPa with 12.7 ± 1.3% elongation, and first-principles calculations give an antiphase-boundary energy of 189 mJ·m−2, underpinning a ∼570 MPa order-strengthening contribution.
This study reports a cast Al-Si-Mg alloy exhibiting significantly enhanced age-hardening response via Cd and Cu additions. Strong Cd-Mg-vacancy, Cd-Si-vacancy and Cd-Cu-vacancy binding promote rapid formation of Cd-Mg-Si(-Cu) clusters, accelerating initial age-hardening kinetics. These clusters evolve into abundant composite structures of Cd-rich precipitates epitaxially connected with β″/Q′/C precipitates, elevating peak-aged strength. Additionally, over-ageing softening is suppressed via (i) Cd-refined precipitate size and homogenized size distribution, and (ii) slow-coarsening Cu-containing Q′/C precipitates. The resulting high density of fine precipitates promotes strong work hardening, conferring superior ductility under both peak- and over-aged conditions.
Materials design often faces an exploration blind spot where trial-and-error methods are inefficient and data-driven approaches struggle to discover new precipitate phases. Here, we propose High-Throughput Precipitate Informatics (HTPI), integrating physics-driven discovery, data-driven optimization, thermodynamic validation, and experimental verification. HTPI screens over 2 million crystallographic combinations within 2 min and identifies a previously unreported AlLiSi phase as a promising nanoscale precipitate in the age-hardening-blind Al-Si system. Machine-learning-guided Al-0.25Si-0.2Li (-0.2Mg) alloys exhibit pronounced age hardening, demonstrating HTPI as an extendable route for precipitate discovery across diverse alloy systems.
