Defects and Interfaces: Their Role During Phase Transformations in Aluminium-Silver Alloys

The story of metallurgy is a story of civilisation. Physical metallurgy concerns the fundamentals and applications of phase transformations: the process in which atoms arrange themselves from one structure to another. Al-Ag alloys have served as a textbook system for understanding the solid-state phase transformations. Using transmission electron microscopy and atomistic calculations, Zezhong found a new precipitate phase, zeta (AgAl), in this classical system. In-situ microscopy and electron tomography revealed phase transformations in time and space. Zezhong illustrated the importance of defects and interfaces, and how to use them to tailor the precipitation behaviour.