University of Minnesota
Aerospace Engineering and Mechanics
Winter 1997 Seminar Series


Microstructural Evolution in Inhomogeneous Elastic Media


Professor Perry Leo

University of Minnesota

Department of Aerospace Engineering and Mechanics



Abstract

We simulate the evolution of microstructures produced by solid-state diffusional phase transformations in two dimensions. The microstructure consists of arbitrarily shaped precipitates embedded coherently in an infinite elastic matrix. The phases are taken to be elastically anisotropic with different elastic constants (elastically inhomogeneous). Both mismatch strains between the phases and arbitrary far-field strains are allowed. Diffusion and elastic fields are calculated by using the boundary integral method, and the precipitate-matrix interfaces are tracked by using a non-stiff time integrating method. Results show that precipitate shapes depend strongly on far-field flux and elastic fields. Growing shapes tend to form dendritic structures, while coarsening shapes tend to be smooth. Simulations of multiparticle systems show complicated elastic interactions involving precipitate merging, translation and alignment. These interactions depend on the elastic inhomogeneity as well as the details of the applied and misfit strains.

Friday, January 10, 1997
209 Akerman Hall, 2:30 - 3:30 p.m.


Refreshments served after each seminar in 227 AKERMAN HALL .
Disability accommodations provided upon request.
Contact Leslie Petrus : Secretarial Assistant.

petrus@aem.umn.edu (612) 625-8000.