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Supercooling and structure of levitation melted Fe-Ni alloysA study has been made of the effect of supercooling, quenching rate, growth inhibitors, and grain refiners on the structure of levitation-melted Fe- 25 pct Ni alloys. A combination of three morphologies, dendritic, spherical, and mixed dendritic and spherical, is observed in samples superheated or supercooled by less than 175 K. At larger supercooling, however, only the spherical morphology is observed. The grain size and the grain boundary shape are found to be strongly dependent on the subgrain morphology but not on the quenching temperature. Considerable grain growth is evident in samples with spherical and mixed morphologies but not in the dendriitic samples. The average cooling rates during solidification and the heat transfer coefficients at the metal-quenching medium boundary are calculated. For samples solidified in water, molten lead, and ceramic molds, the heat transfer coefficients are 0.41, 0.52, and 0.15 w/sq cm, respectively.
Document ID
19830054472
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Abbaschian, G. J.
(Florida, University Gainesville, FL, United States)
Flemings, M. C.
(MIT Cambridge, MA, United States)
Date Acquired
August 11, 2013
Publication Date
June 1, 1983
Publication Information
Publication: Metallurgical Transactions A - Physical Metallurgy and Materials Science
Volume: 14A
ISSN: 0360-2133
Subject Category
Metallic Materials
Accession Number
83A35690
Funding Number(s)
CONTRACT_GRANT: N00014-81-K-0730
CONTRACT_GRANT: NSG-7645
Distribution Limits
Public
Copyright
Other

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