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Indexed by:期刊论文

Date of Publication:2013-09-01

Journal:CERAMICS INTERNATIONAL

Included Journals:SCIE、EI、Scopus

Volume:39

Issue:7

Page Number:7445-7452

ISSN No.:0272-8842

Key Words:Eutectic ceramic; Melt superheating treatment; Microstructure evolution; Melt undercooling; Microstructure refinement

Abstract:Microstructure developments of melt-grown Al2O3/YAG/ZrO2 ceramic bulks were investigated by controlling composition, cooling rate, heterogeneous nucleation sites and melt superheating treatment. The solidification microstructure of sample with hypereutectic composition (ZrO2 20 mol%) is finer than that with hypoeutectdc or eutectic ones. With increasing the cooling rate, microstructure of melt-grown samples develops from colony to dendrite and finally to cell. The microscopy and the components of samples vary with the melt superheating temperature and the type of heterogeneous nucleation sites. The microstructure evolutions of melt-grown Al2O3/YAG/ZrO2 eutectic relate to the melt undercooling level and the solid-liquid interfaces stability. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.