High-strength and temperature-stable formed bodies of zirconium dioxide
AssigneeMax-Planck-Gesellschaft zur Foerderung der Wissenschaften e.V.
InventorsNils Claussen, Helmut Schubert, Manfred Ruhle, Gunter Petzow
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Abstract
The present invention provides a fine-grained ceramic formed body of 0.5 to mole % rare earth oxide and 0.5 to 7 mole % MgO-containing ZrO.sub.2, wherein the cubic granules thereof are coated with Mg-Al spinel particles. The present invention also provides a process for the production of such formed bodies, wherein a ZrO.sub.2 powder alloyed with rare earth oxide, which contains small amounts of Al.sub.2 O.sub.3, is pressed and sintered in the presence of MgO at a temperature of from 1400.degree. to 1600.degree. C. and optionally subsequently tempered at a temperature of from 1200.degree. to 1350.degree. C.
Claims7
A process for the production of a formed body comprising:
- pressing a powder consisting essentially of ZrO.sub.2 powder alloyed with 0.5 to 4 mole % rare earth oxide or SrO, which contains about 0.1 to 5% by volume of Al.sub.2 O.sub.3, in the presence of MgO to form a pressed body;
- and sintering the pressed body in an MgO containing atmosphere at a temperature of from 1400.degree. to 1600.degree. C.
The process of claim 16 wherein the rare earth oxide is y.sub.2 O.sub.3.
A process for the production of a formed body comprising:
- pressing a powder consisting essentially of ZrO.sub.2 powder alloyed with 0.5 to 4 mole % rare earth oxide or SrO, which contains about 0.1 to 5% by volume of Al.sub.2 O.sub.3, in the presence of MgO to form a pressed body;
- sintering the pressed body in air at a temperature of from 1350.degree. to 1450.degree. C. to form a sintered body;
- and, subsequently calcining the sintered body in an MgO-containing atmosphere at a temperature of from 1450.degree. to 1650.degree. C.
Dependencies are inferred from the claim text.