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Thermal Expansion Reduction in Alumina‐Toughened Zirconia by Incorporation of Zirconium Tungstate and Aluminum Tungstate
Author(s) -
Romao Carl P.,
Marinkovic Bojan A.,
WernerZwanziger Ulrike,
White Mary Anne
Publication year - 2015
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/jace.13675
Subject(s) - thermal expansion , tungstate , materials science , cubic zirconia , sintering , yttria stabilized zirconia , composite material , zirconium , aluminium , negative thermal expansion , phase (matter) , thermal , metallurgy , ceramic , thermodynamics , chemistry , physics , organic chemistry
A series of composites containing yttria‐stabilized zirconia, Al 2 O 3 , and the thermomiotic (negative thermal expansion) materials ZrW 2 O 8 and Al 2 W 3 O 12 were prepared by an in situ solid‐state reaction during sintering. Microstructural analysis of the composites indicated several sub‐micron sized components. 27 Al MAS NMR was used to characterize the aluminum‐containing phase distribution. Measurement of the coefficients of thermal expansion showed that the addition of thermomiotic components reduced the thermal expansivity of the alumina‐toughened zirconia matrix, but the reduction was considerably smaller than what would be predicted by the rule of mixtures. The Turner model was much more accurate in predicting the coefficients of thermal expansion of the composites due to the large differences in stiffness between the components.