Compositions: ceramic – Ceramic compositions – Refractory
Reexamination Certificate
2006-03-14
2006-03-14
Sample, David (Department: 1755)
Compositions: ceramic
Ceramic compositions
Refractory
C501S127000, C501S152000, C501S153000
Reexamination Certificate
active
07012036
ABSTRACT:
A ZrO2—Al2O3composite ceramic material having high mechanical strength and toughness as well as excellent wear resistance and hardness is provided. This ceramic material includes a first phase of ZrO2grains containing 10 to 12 mol % of CeO2as a stabilizer and having an average grain size of 0.1 μm to 1 μm, and a second phase of Al2O3grains having an average grain size of 0.1 to 0.5 μm. The ceramic material has a mutual nano-composite structure formed under a condition that a content of the second phase in the ceramic material is within a range of 20 to 60 vol % such that the Al2O3grains are dispersed within said ZrO2grains at a first dispersion ratio of 2% or more, and preferably 4% or more, which is defined as a ratio of the number of the Al2O3grains dispersed within the ZrO2grains relative to the number of the entire Al2O3grains dispersed in the ceramic material, and the ZrO2grains are dispersed within the Al2O3grains at a second dispersion ratio of 1% or more, which is defined as a ratio of the number of the ZrO2grains dispersed within the Al2O3grains relative to the number of the entire ZrO2grains dispersed in the ceramic material.
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Nawa Masahiro
Toki Motoyuki
Yamaguchi Kouichi
Matsushita Electric & Works Ltd.
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
Sample David
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