2019/08/05 by Vladyslav Turlo, Timothy J. Rupert, Turlo, Vladyslav +1 · 1 citation
Engineering · Materials Science · #Advanced Materials Characterization Techniques #Aluminum Alloy Microstructure Properties #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Microstructure and mechanical properties
paper · pdf · doi:10.48550/arxiv.1908.01849
openalex publication_date 2019/08/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Linear complexions are defect states that have been recently discovered along\ndislocations in body centered cubic Fe-based alloys. In this work, we use\natomistic simulations to extend this concept and explore segregation-driven\nstructural transitions at dislocations in face centered cubic alloys. We\nidentify a variety of stable, nanoscale-size structural and chemical states,\nwhich are confined near dislocations and can be classified as linear\ncomplexions. Depending on the alloy system and thermodynamic conditions, such\nnew states can preserve, partially modify, or completely replace the original\ndefects they were born at. By considering different temperatures and\ncompositions, we construct linear complexion diagrams that are similar to bulk\nphase diagrams, defining the important conditions for complexion formation\nwhile also specifying an expected complexion size and type. Several notable new\ncomplexion types were predicted here: (1) nanoparticle arrays comprised of L12\nphases in Ni-Fe, Ni-Al, and Al-Zr, (2) replacement of stacking faults with\nlayered complexions comprised of (111) planes from the Cu5Zr intermetallic\nphase in Cu-Zr, (3) platelet arrays comprised of two-dimensional\nGuinier-Preston zones in Al-Cu, and finally (4) coexistence of multiple linear\ncomplexions containing both Guinier-Preston zones and L12 phases in ternary\nAl-Cu-Zr. All of these new complexion states are expected to alter material\nproperties and affect the stability of the dislocations themselves, offering a\nunique opportunity for future materials design.\n