University of Minnesota
Aerospace Engineering and Mechanics
Spring 2001 Seminar Series



A Sharp Interface Model for Martensitic Single Crystal Thin Films


Prof. Mitchell Luskin

School of Mathematics, University of Minnesota


Abstract

Martensitic thin films are being used as the active element in actuators, sensors, and micromachines. Single-crystal martensitic thin films have recently been grown in the laboratory by Palmstrøm and theoretically offer even larger displacements during the solid-solid phase transformation.

Bhattacharya and James have derived a thin film variational principle from the three-dimensional elastic energy for martensitic crystals with the surface energy density modeled by the square of the strain gradient. We give a derivation of an alternative thin film variational principle in which the interfacial energy is modeled by the total variation of the deformation gradient. Deformations of finite energy can have sharp interfaces with our model, and more efficient finite element approximations can be used for the deformation.

We will present numerical methods and computational results for the simulation of the deformation of a martensitic single crystal thin film during thermally activated and stress induced phase changes.

Friday, February 9, 2001
209 Akerman Hall
2:30-3:30 p.m.


Refreshments served after the seminar in 227 Akerman Hall.
Disability accomodations provided upon request.
Contact Kristal Belisle, Senior Secretary, 625-8000.