biostudies-literatureZhang CFundamental Research Funds for the Central Universities111 project of ChinaShaanxi Province Innovation Team ProjectNational Natural Science Foundation of Chinae02349https://www.ebi.ac.uk/biostudies/studies/S-EPMC12376552biostudies-literatureUnknown12(30)Duplex (α+β) Ti alloys often manifest limited uniform elongation (ε_u) mainly originating from the lack of <c+a> dislocations for insufficient work hardening capability and semi-coherent α/β interfaces for strain incompatibility. The strength-ductility trade-off of duplex Ti alloys is further amplified by interstitial atoms-poisoning effects (e.g., N and O). Here, by selecting N atoms with the strongest hardening ability in Ti alloys, a counterintuitive strategy is proposed that harnesses bifunctional N-dislocation interactions in a model duplex Ti-Cr-Zr-Al alloy to construct a heterogeneous lamella structure, involving the elongated α_p grains decorated with N-rich low-angle grain boundaries (LAGBs) and densely coherent interstitial-N α'-nanotwinned martensites in β-grAdvanced science (Weinheim, Baden-Wurttemberg, Germany)Harnessing Bifunctional Nitrogen-Dislocation Interactions for a Record Ultra-Strong-and-Ductile Duplex Titanium Alloy.PMC123765522024RS-CXTD-589236030152441407xtr062024006U23302039216320152431006523B2004U23A6013Li XLi SZhang JZhang CSun JLiu GfalseHarnessing Bifunctional Nitrogen-Dislocation Interactions for a Record Ultra-Strong-and-Ductile Duplex Titanium Alloy.Duplex (α+β) Ti alloys often manifest limited uniform elongation (ε_u) mainly originating from the lack of <c+a> dislocations for insufficient work hardening capability and semi-coherent α/β interfaces for strain incompatibility. The strength-ductility trade-off of duplex Ti alloys is further amplified by interstitial atoms-poisoning effects (e.g., N and O). Here, by selecting N atoms with the strongest hardening ability in Ti alloys, a counterintuitive strategy is proposed that harnesses bifunctional N-dislocation interactions in a model duplex Ti-Cr-Zr-Al alloy to construct a heterogeneous lamella structure, involving the elongated α_p grains decorated with N-rich low-angle grain boundaries (LAGBs) and densely coherent interstitial-N α'-nanotwinned martensites in β-gr2025-01-01T00:00:00Z2025 Aug2026-05-09T17:51:30.953Z2026-04-08T01:07:02.671ZS-EPMC123765524053673310.1002/advs.202502349