Influence of Crystal Morphological Parameters on the Solidification of ESR Ingot

Abstract:

Electroslag remelting (ESR) is an advanced process to produce high quality steel. During the ESR process, the steel electrode is melted and then solidified directionally in a water-cooled mold. The quality of the ingot is strongly dependent on the shape of melt pool, i.e. the depth and thickness of mushy zone, which is in turn influenced by the bulk and interdendritic flow. Here, we perform a numerical study to investigate the effect of crystal morphological parameter such as primary dendrite arm spacing on the solidification of the ESR ingot ( 750 mm). The crystal morphology is dominantly columnar and dendritic, thus a mixture enthalpy-based solidification model is used. Accordingly the mushy zone is considered as a porous media where the interdendritic flow is calculated based on the permeability. The permeability is determined as function of the liquid fraction and primary dendrite arm spacing according to Heinrich and Poirier [Comptes Rendus Mecanique, 2004, pp. 429-44]. The modeling results were verified against experimental results.

• Periodical: Materials Science Forum (Volumes 790-791)
• Pages: 396-401
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.790-791.396
• Online since: May 2014
• Authors: Ebrahim Karimi-Sibaki*, Abdellah Kharicha, J. Korp, Meng Huai Wu, Andreas Ludwig
• Keywords: AC Frequency, Dendrite Arm Spacing, Electroslag Remelting, Permeability

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