A Comprehensive Analysis of Macrosegregation Formation During Twin-Roll Casting
- Montanuniversitaet Leoben, Metallurgy Department (Austria)
- Montanuniversitaet of Leoben, Christian-Doppler Laboratory for Metallurgical Application of Magnetohydrodynamics (Austria)
A two-phase Eulerian–Eulerian volume-averaged model is used to predict the formation of macrosegregation during the twin-roll casting of inoculated Al-4 wt pct Cu alloys. For low solid fractions, the equiaxed crystals are modeled according to the submerged object approach. However, above a given transition limit, they are assumed to behave like a viscoplastic material. This means that the solid phase behaves as a coherent structure that can influence the motion of the liquid. Such approach allows one to take into account the flow dynamics arising from the occurrence of both solidification and hot rolling simultaneously, which usually occurs in twin-roll casting. Therefore, it is possible to explain the origin of the macrosegregation patterns obtained in the simulations based on the relative motion between the phases. Compression-induced expulsion of segregated melt is observed as a result of the deformation of the solidifying shells. Such occurrence leads to a negative macrosegregation region in the outer part of the as-cast strip. Then, because the solute-enriched melt is squeezed out toward adjacent regions, two positively segregated bands can be found near the center of the domain. Furthermore, it is shown how solidification-induced feeding weakens the absolute value of the negative and positive segregation bands.
- OSTI ID:
- 22933717
- Journal Information:
- Metallurgical and Materials Transactions. B, Process Metallurgy and Materials Processing Science, Vol. 50, Issue 3; Other Information: Copyright (c) 2019 The Minerals, Metals & Materials Society and ASM International; Article Copyright (c) 2019 The Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 1073-5615
- Country of Publication:
- United States
- Language:
- English
Similar Records
Modeling of macrosegregation due to thermosolutal convection and contraction-driven flow in direct chill continuous casting of an Al-Cu round ingot
Combined experimental and numerical investigation of the formation of macrosegregation during multicomponent steel solidification