Effect of Temperature and Fluid Flow on Dendrite Growth During Solidification of Al-3 Wt Pct Cu Alloy by the Two-Dimensional Cellular Automaton Method

Journal Article · Fri Dec 15 04:00:00 EST 2017 · Metallurgical and Materials Transactions B, Process Metallurgy and Materials Processing Science

DOI:https://doi.org/10.1007/S11663-017-1060-3· OSTI ID:22856099

Gu, Cheng; Wei, Yanhong; Liu, Renpei; Yu, Fengyi ^[1]

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1. Nanjing University of Aeronautics and Astronautics, College of Material Science and Technology (China)

A two-dimensional cellular automaton–finite volume model was developed to simulate dendrite growth of Al-3 wt pct Cu alloy during solidification to investigate the effect of temperature and fluid flow on dendrite morphology, solute concentration distribution, and dendrite growth velocity. Different calculation conditions that may influence the results of the simulation, including temperature and flow, were considered. The model was also employed to study the effect of different undercoolings, applied temperature fields, and forced flow velocities on solute segregation and dendrite growth. The initial temperature and fluid flow have a significant impact on the dendrite morphologies and solute profiles during solidification. The release of energy is operated with solidification and results in the increase of temperature. A larger undercooling leads to larger solute concentration near the solid/liquid interface and solute concentration gradient at the same time-step. Solute concentration in the solid region tends to increase with the increase of undercooling. Four vortexes appear under the condition when natural flow exists: the two on the right of the dendrite rotate clockwise, and those on the left of the dendrite rotate counterclockwise. With the increase of forced flow velocity, the rejected solute in the upstream region becomes easier to be washed away and enriched in the downstream region, resulting in acceleration of the growth of the dendrite in the upstream and inhibiting the downstream dendrite growth. The dendrite perpendicular to fluid flow shows a coarser morphology in the upstream region than that of the downstream. Almost no secondary dendrite appears during the calculation process.

• OSTI ID: 22856099
• Journal Information: Metallurgical and Materials Transactions B, Process Metallurgy and Materials Processing Science, Journal Name: Metallurgical and Materials Transactions B, Process Metallurgy and Materials Processing Science Journal Issue: 6 Vol. 48; ISSN MTBSEO; ISSN 1073-5615
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
COMPUTERIZED SIMULATION
CONCENTRATION RATIO
COPPER ALLOYS
DENDRITES
FLUID FLOW
LIQUIDS
MORPHOLOGY
SEGREGATION
SOLIDIFICATION
SOLIDS
SOLUTES
SUBCOOLING
TEMPERATURE DEPENDENCE
TWO-DIMENSIONAL CALCULATIONS
TWO-DIMENSIONAL SYSTEMS