A sharp-interface model for diffusional evolution of precipitates in visco-plastic materials

authored by
Lukas Munk, Silvia Reschka, Stefan Löhnert, Hans Jürgen Maier, Peter Wriggers
Abstract

This paper describes a 3D implementation of the sharp-interface theory for material heterogeneities and is, hence, able to identify equilibrium shapes of precipitates in superalloys. The theory is adopted from Morton E. Gurtin and extended by crystal plasticity in the bulk. Crystal plasticity relaxes stresses at the phase interface, which leads to subsequent coalescence of the precipitates. The fully implicit model employs the extended finite element method (XFEM) in conjunction with level sets. The level set is advected in a velocity field computed by the stress-modified Gibbs-Thomson interface condition. Mechanical equilibrium and level set update are solved in a staggered procedure. Jump quantities are treated by means of a suitable enriched least square smoothing. Multiple schemes for the computation of curvature of surfaces in the context of the XFEM are presented and compared. Equilibrium shapes at different levels of misfit are computed. A cuboidal equilibrium shape is retrieved in a rotated mesh in order to quantify mesh-independence, a linear volume-time relationship during Ostwald ripening is reproduced and merging of particles under tension is reported.

Organisation(s)
Institute of Continuum Mechanics
Institute of Materials Science
External Organisation(s)
Technische Universität Dresden
Type
Article
Journal
Computer Methods in Applied Mechanics and Engineering
Volume
391
ISSN
0045-7825
Publication date
01.03.2022
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Computational Mechanics, Mechanics of Materials, Mechanical Engineering, Physics and Astronomy(all), Computer Science Applications
Electronic version(s)
https://doi.org/10.1016/j.cma.2021.114440 (Access: Closed)
 

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