Investigations of fluid flow effects on dendritic solidification: Consequences on fragmentation, macrosegregation and the influence of electromagnetic stirring

Final LIMTECH Colloquium and International Symposium on Liquid Metal Technologies

材料科学;金属学

Shevchenko, N.^1 ; Neumann-Heyme, H.^1 ; Pickmann, C.^2 ; Schaberger-Zimmermann, E.^3 ; Zimmermann, G.^2 ; Eckert, K.^1 ; Eckert, S.^1

Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden

01328, Germany^1

ACCESS E.V., Intzestrasse 5, Aachen

52072, Germany^2

RWTH, Foundry Institute, Intzestrasse 5, Aachen

52072, Germany^3

关键词: Convective transport;    Dendrite orientation;    Dendritic solidification;    Dendritic structures;    Density variations;    Electromagnetic stirring;    Grain morphologies;    Segregation phenomena;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/228/1/012005/pdf
DOI  :  10.1088/1757-899X/228/1/012005

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Solidification experiments and numerical simulations have been performed to improve the understanding of the complex interrelation between melt flow and the formation of dendritic structures during solidification of Al-Cu and Ga-In alloys. Melt flow induces various effects on grain morphology primarily caused by convective transport of solute, such as a facilitation of the growth of primary trunks or lateral branches, dendrite remelting, fragmentation or freckle formation depending on the dendrite orientation, the flow direction and intensity. Within this project special interest was focused on fragmentation and segregation phenomena. Natural convection is caused by density variations within the solidifying alloys. Forced convection was produced by electromagnetic stirring. X-ray radioscopy was applied as a powerful tool for the visualization of dendritic growth and coarsening.