Gyula I. Tóth

8568732900

Publications - 2

Phase-field modeling of eutectic structures on the nanoscale: the effect of anisotropy

Publication Name: Journal of Materials Science

Publication Date: 2017-05-01

Volume: 52

Issue: 10

Page Range: 5544-5558

Description:

A simple phase-field model is used to address anisotropic eutectic freezing on the nanoscale in two (2D) and three dimensions (3D). Comparing parameter-free simulations with experiments, it is demonstrated that the employed model can be made quantitative for Ag–Cu. Next, we explore the effect of material properties and the conditions of freezing on the eutectic pattern. We find that the anisotropies of kinetic coefficient and the interfacial free energies (solid–liquid and solid–solid), the crystal misorientation relative to pulling, the lateral temperature gradient play essential roles in determining the eutectic pattern. Finally, we explore eutectic morphologies, which form when one of the solid phases are faceted, and investigate cases, in which the kinetic anisotropy for the two solid phases is drastically different.

Open Access: Yes

DOI: 10.1007/s10853-017-0853-8

Phase-field modeling of polycrystalline solidification: From needle crystals to spherulites - A review

Publication Name: Metallurgical and Materials Transactions A Physical Metallurgy and Materials Science

Publication Date: 2014-01-01

Volume: 45

Issue: 4

Page Range: 1694-1719

Description:

Advances in the orientation-field-based phase-field (PF) models made in the past are reviewed. The models applied incorporate homogeneous and heterogeneous nucleation of growth centers and several mechanisms to form new grains at the perimeter of growing crystals, a phenomenon termed growth front nucleation. Examples for PF modeling of such complex polycrystalline structures are shown as impinging symmetric dendrites, polycrystalline growth forms (ranging from disordered dendrites to spherulitic patterns), and various eutectic structures, including spiraling two-phase dendrites. Simulations exploring possible control of solidification patterns in thin films via external fields, confined geometry, particle additives, scratching/piercing the films, etc. are also displayed. Advantages, problems, and possible solutions associated with quantitative PF simulations are discussed briefly. © 2013 The Minerals, Metals & Materials Society and ASM International.

Open Access: Yes

DOI: 10.1007/s11661-013-1988-0