A three-dimensional polyhedral unit model for grain boundary structure in fcc metals

Abstract

Polyhedral structures: Building blocks for metallic interfaces US researchers have designed a model to aid understanding of how crystals pack in metals such as aluminum and copper. Most metals form as polycrystalline microstructures, i.e., they are composed of small crystals of varying size and orientation. The lack of structural order, along the interfaces where crystals of different orientations meet, makes it difficult to model their properties. Arash Banadaki and Srikanth Patala at North Carolina State University have taken the first step towards quantifying these relationships, by developing a three-dimensional model that classifies the geometrical nature of how atoms pack along these disordered regions in the microstructure. The model was tested on face-centered cubic crystals, but is also applicable to systems with different lattice structures. This is a key first step in the bottom-up design of structural materials with desired properties.