University of California - Irvine Irvine United States
This project sought to develop bulk nanostructured materials with high strength and ductility, utilizing amorphous intergranular films AIFs as features that enable both consolidation and enhanced mechanical properties. These amorphous films are in equilibrium, meaning they are stable grain boundary structures, but should also improve grain boundary diffusivity and the ability of an interface to absorb dislocations without cracking. The proposed research answered fundamental questions about the importance of grain boundary complexions for mechanical damage and thermal stability. What alloy compositions and heat treatment temperatures lead to the formation of different complexions in a nanocrystalline metal How do complexions affect mechanical behavior and consolidation How does processing affect complexion type and thickness In the end, we were able to extend the concept of interfacial engineering, by adding another design variable to the toolbox that materials engineers can use to control mechanical properties and thermal stability simultaneously.