A Sharp-Interface Model of the Diffusive Phase Transformation in a Nickel-Based Superalloy

authored by: Lukas Munk, Silvia Reschka, Hans Jürgen Maier, Peter Wriggers, Stefan Löhnert
Abstract: A sharp-interface model employing the extended finite element method is presented. It is designed to capture the prominent (Formula presented.) - (Formula presented.) phase transformation in nickel-based superalloys. The novel combination of crystal plasticity and sharp-interface theory outlines a good modeling alternative to approaches based on the Cahn–Hilliard equation. The transformation is driven by diffusion of solute (Formula presented.) -forming elements in the (Formula presented.) -phase. Boundary conditions for the diffusion problem are computed by the stress-modified Gibbs–Thomson equation. The normal mass balance of solute atoms at the interface yields the normal interface velocity, which is integrated in time by a level set procedure. In order to capture the influence of dislocation glide and climb on interface motion, a crystal plasticity model is assumed to describe the constitutive behaviour of the (Formula presented.) -phase. Cuboidal equilibrium shapes and Ostwald ripening can be reproduced. According to the model, in low (Formula presented.) volume-fraction alloys with separated (Formula presented.) -precipitates, interface movement does not have a significant effect on tensile creep behaviour at various lattice orientations.
Organisation(s): Institute of Materials Science
Institute of Continuum Mechanics
External Organisation(s): Technische Universität Dresden
Type: Article
Journal: Metals
Volume: 12
ISSN: 2075-4701
Publication date: 08.2022
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: General Materials Science, Metals and Alloys
Electronic version(s): https://doi.org/10.3390/met12081261 (Access: Open)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{121e508542f44807be30d4ca0c0f2132,
title = "A Sharp-Interface Model of the Diffusive Phase Transformation in a Nickel-Based Superalloy",
abstract = "A sharp-interface model employing the extended finite element method is presented. It is designed to capture the prominent (Formula presented.) - (Formula presented.) phase transformation in nickel-based superalloys. The novel combination of crystal plasticity and sharp-interface theory outlines a good modeling alternative to approaches based on the Cahn–Hilliard equation. The transformation is driven by diffusion of solute (Formula presented.) -forming elements in the (Formula presented.) -phase. Boundary conditions for the diffusion problem are computed by the stress-modified Gibbs–Thomson equation. The normal mass balance of solute atoms at the interface yields the normal interface velocity, which is integrated in time by a level set procedure. In order to capture the influence of dislocation glide and climb on interface motion, a crystal plasticity model is assumed to describe the constitutive behaviour of the (Formula presented.) -phase. Cuboidal equilibrium shapes and Ostwald ripening can be reproduced. According to the model, in low (Formula presented.) volume-fraction alloys with separated (Formula presented.) -precipitates, interface movement does not have a significant effect on tensile creep behaviour at various lattice orientations.",
keywords = "crystal plasticity, diffusion, phase transformation, sharp-interface theory, XFEM",
author = "Lukas Munk and Silvia Reschka and Maier, {Hans J{\"u}rgen} and Peter Wriggers and Stefan L{\"o}hnert",
note = "Funding Information: This work was supported by the LUH compute cluster, which is funded by the Leibniz Universit{\"a}t Hannover, the Lower Saxony Ministry of Science and Culture (MWK), and the German Research Association (DFG). Funding Information: The authors gratefully acknowledge financial support by Deutsche Forschungsgemeinschaft (DFG) through grant no. 282253287. The publication of this article was funded by the Open Access Fund of Leibniz Universit{\"a}t Hannover.",
year = "2022",
month = aug,
doi = "10.3390/met12081261",
language = "English",
volume = "12",
journal = "Metals",
issn = "2075-4701",
publisher = "Multidisciplinary Digital Publishing Institute",
number = "8",
}