Modeling of charge welds evolution through Cahn-Hilliard equation for interaction between different Fluids: Experimental-numerical comparison with industrial case studies
Sara Di Donato, Riccardo Pelaccia, Marco Negozio, Barbara Reggiani, Lorenzo Donati
Abstract. In the hot extrusion process for metals, the interaction between the old and new billet materials during each cycle contaminates a specific length of the extruded profile. Experimental analysis of defect evolution is both time-intensive and costly, while empirical industrial methods and analytical formulas lack the precision required in scenarios where minimizing scrap is critical. To address this, a numerical model was developed using COMSOL Multiphysics® software, coupling the Navier-Stokes equations with the Cahn-Hilliard equation to investigate the interaction between two immiscible fluids with very high viscosities—representing the old and new billet materials. The model’s accuracy was validated through four industrial case studies, that varied in terms of profile-shape complexity and material extruded.
Keywords
Extrusion, Charge Welds Defects, Advanced Numerical Simulation, Aluminum Alloys
Published online 5/7/2025, 10 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Sara Di Donato, Riccardo Pelaccia, Marco Negozio, Barbara Reggiani, Lorenzo Donati, Modeling of charge welds evolution through Cahn-Hilliard equation for interaction between different Fluids: Experimental-numerical comparison with industrial case studies, Materials Research Proceedings, Vol. 54, pp 799-808, 2025
DOI: https://doi.org/10.21741/9781644903599-86
The article was published as article 86 of the book Material Forming
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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