Abstract
In the absence of grain-refining additions to a melt or of any significant heterogeneous nuclei, equiaxed grains can only originate in a casting from primary dendrite fragments. Thus, it is pertinent to understand how dendrites become fragmented and to explain why liquid stirring should appear to “break up” and refine the grain structure. Dendrite fragmentation occurs by local remelting, and fluid flow is important as a dispersal mechanism.
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Additional information
A. Hellawell earned his D.Phil. in physical science at Oxford University in 1956. He is currently emeritus research professor at Michigan Technological University. He is also a member of TMS.
S. Liu earned his M.S. in materials science and engineering at Northwestern Polytechnical University, China, in 1989. He is currently a Ph.D. candidate at Michigan Technological University.
S.Z. Lu earned his Ph.D. in metallurgical engineering at Michigan Technological University in 1986. He is currently a research associate professor at Michigan Technological University. He is also a member of TMS.
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Hellawell, A., Liu, S. & Lu, S.Z. Dendrite fragmentation and the effects of fluid flow in castings. JOM 49, 18–20 (1997). https://doi.org/10.1007/BF02914650
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DOI: https://doi.org/10.1007/BF02914650