Journal Article

Periodic Segregation of Solute Atoms in Fully Coherent Twin Boundaries

Zhu, Y. M., Nie, J. F., Liu, J. Z., Fang, X. Y.

2013

Overview

The formability and mechanical properties of many engineering alloys are intimately related to the formation and growth of twins. Understanding the structure and chemistry of twin boundaries at the atomic scale is crucial if we are to properly tailor twins to achieve a new range of desired properties. We report an unusual phenomenon in magnesium alloys that until now was thought unlikely: the equilibrium segregation of solute atoms into patterns within fully coherent terraces of deformation twin boundaries. This ordered segregation provides a pinning effect for twin boundaries, leading to a concomitant but unusual situation in which annealing strengthens rather than weakens these alloys. The findings point to a platform for engineering nano-twinned structures through solute atoms. This may lead to new alloy compositions and thermomechanical processes.

• Publisher: American Association for the Advancement of Science,The American Association for the Advancement of Science
• Subject: Alloys / Annealing / Atoms / Boundaries / Chemical engineering / Coherence / Condensed matter: structure, mechanical and thermal properties / Crystal defects / Crystal twinning / Defects and impurities in crystals; microstructure / energy / Exact sciences and technology / Grain and twin boundaries / Impurities / Kinetics / Magnesium / Materials / Materials science / Mechanical engineering / Mechanical properties / Metallurgy / Optimization / Organic Chemistry / Physics / Segregations / Solid solutions / Solutes / Strength / Structure of solids and liquids; crystallography / synergism / Synergistic effect / Twin boundaries / Twins