Zirconia-alumina ceramic materials
AssigneeAktiebolaget Skf
InventorsLars Kahlman, Charlotte Vieillard, Jelena Sekulic, Knut Henrik Johensen, Hans Hillen Schjelderup
Life of this patent
Estimating the term…
Abstract
The present invention provides a ceramic material comprising: a first phase comprising zirconia, yttrium and cerium, wherein the yttrium and cerium are present in a molar ratio of 0.15 to 0.5 and in a combined amount of 5 to 15 mol %, a second phase comprising alumina, and a third phase comprising metal aluminate platelets.
Claims19
A ceramic material comprising:
- a first phase comprising zirconia, yttrium and cerium, wherein the yttrium and cerium are present in a molar ratio of 0.15 to 0.5 and in a combined amount of 5 to 15 mol %,
- a second phase comprising alumina, and
- a third phase comprising metal aluminate platelets.
A ceramic material consisting of:
- 50 to 75 wt % of a zirconia matrix,
- 25 to 49.5 wt % of alumina,
- 0.5 to 5 wt % metal aluminate platelets,
- and any unavoidable impurities,
- wherein the zirconia matrix comprises a composite of zirconia containing yttrium in an amount of 1 to 10 mol % and zirconia containing cerium in an amount of 5 to 20 mol %, wherein the yttrium-containing zirconia and the cerium-containing zirconia are present in a weight ratio of 1:5 to 2:1.
A method of manufacturing a ceramic material comprising zirconia and alumina, the method comprising:
- spraying a slip comprising zirconia, alumina and metal aluminate platelets and/or a metal aluminate platelet precursor through a nozzle to form droplets,
- freeze drying or spray drying of these droplets to form granules,
- pressing the granules to form a green body, and
- sintering the green body, wherein metal aluminate platelets are formed from the, metal aluminate platelet precursor during the sintering of the green body.
The bearing component of claim 14, wherein a rolling surface of the bearing component is formed from the ceramic material.
Dependencies are inferred from the claim text.