EAGER: Constitutive Relations in Amorphous Metals

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

The research objective of this EArly-concept Grant for Exploratory Research (EAGER) project is to elucidate the fundamental mechanisms and constitutive relations in amorphous metals. Amorphous or metallic glass is a structurally disordered solid without the long-range translational order. This topological disorder leads to some of the most remarkable mechanical properties for this class of materials. In the past decade, extensive research and development have been done to harvest the properties, especially the mechanical properties, which led to several constitutive relations. However, these relations suffer from both conceptual difficulties and lack of critical experimental support. In particular, two constitutive models are going to be tested: one is based on Drucker-Prager criterion and transition state theory; and the second, a new theory for plasticity, is the free energy-based approach. Both FEM and atomistic modeling are planned. The ultimate goal of this research is to establish the constitutive relations among stress, strain, strain rate, temperature, and various physical, structural properties and compositional changes for amorphous solids, which is one of the remaining frontiers in mechanics of materials where no working constitutive model exists to date. This exercise will not only help the scientific community to get closer to more physically justified and working constitutive models for metallic glasses, but will also bring the field a step further toward formulation of deformation in topologically disordered solids in general. Thus this effort is expected to contribute to advancements in the area of mechanics of solids. Associated educational plans will be synergistically integrated with the proposed work.