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Sintering, Microstructure, Hardness, and Fracture Toughness Behavior of Y 2 O 3 ‐CeO 2 ‐ZrO 2
Author(s) -
DUH JENQGONG,
DAI HSINGTAO,
CHIOU BISHIOU
Publication year - 1988
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1988.tb07528.x
Subject(s) - sintering , materials science , tetragonal crystal system , microstructure , fracture toughness , coprecipitation , monoclinic crystal system , grain size , mineralogy , calcination , grain growth , crystallography , metallurgy , composite material , chemical engineering , crystal structure , chemistry , biochemistry , engineering , catalysis
A wet‐chemical approach is applied to derive fine powders with compositions 11 mol% CeO 2 ‐ZrO 2 , 1 mol% YO 1.5 ‐10 mol% CeO 2 ‐ZrO 2 , 12 mol% CeO 2 ‐ZrO 2 , and 2 mol% YO 1.5 ‐10 mol% CeO 2 ‐ZrO 2 by the coprecipitation method. The characteristics of the as‐derived powders are evaluated through thermal analysis and electron microscopy. The sintering behavior of the calcined powders is carried out at 1400° and 1500°C for 1 to 10 h. Sintered density higher than 98% of theoretical is achieved for sintering at 1400°C for several hours. The as‐sintered density dependence on the sintering condition is related to the extent of tetragonal‐to‐monoclinic phase transformation as well as the associated microcracks. Partial substitution by Y 2 O 3 in CeO 2 ‐ZrO 2 results in reduced grain size and tends to stabilize the tetragonal structure. Y 2 O 3 is more effective than CeO 2 with respect to the grain size refinement and tetragonal stability. In addition, Y 2 O 3 substitution in CeO 2 ‐ZrO 2 increases the hardness, while it decreases the fracture toughness.