Sixth GAMM Seminar on Microstructures - Abstract

Duderstadt, Frank

Diffusion induced inelastic deformation of crystalline solid mixtures

We describe the coupled process of diffusion and deformation that appears during the evolution of liquid arsenic precipitates in a solid gallium arsenide surrounding. The local constitution of the solid changes in the course of time due to phase transitions at the solid-liquid interfaces and due to diffusion, which leads to diffusion induced changes of the elastic constitutive law. As a result we observe diffusion induced inelastic deformations.
The proposed model is thermodynamically consistent and satisfies exactly the conservation law of mass. These properties are violated in most models that are available in the literature. For example, the most cited Gibbs free energy of a deformed solid, which is found in the textbook by Landau-Lifschitz, violates the second law of thermodynamics. Moreover, most attempts to describe the diffusion process rely on a diffusion equation that violates the conservation law of total mass, and thus can not be used to describe the diffusion problem in gallium arsenide with sufficient accuracy.