Sintered ceramic shaped article wholly or predominantly of eutectic microstructure constituents
AssigneeFeldmuhle Aktiengesellschaft
InventorsUlrich Krohn, Hans Olapinski, Ulf Dworak
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Abstract
Ceramic shaped articles are disclosed which are formed of dense, non-metallic, mechanically resistant materials and contain eutectic constituents consisting of zirconium oxide, hafnium oxide and at least one other high-melting oxide and mixtures thereof. The composition exhibits excellent hardness, wear properties and bending strength. A method for preparing the articles is also disclosed wherein the appropriate mixture in a hypoeutectic, eutectic, or hypereutectic ratio is heated to its melting point, poured into a preheated mold and cooled.
Claims2
In a sintered ceramic shaped article in the form of cutting tools, turbine blades, and similar articles which exhibit excellent hardness wear properties and bending strength, formed by sintering or hot pressing a mixture of dense, non-metallic, mechanically resistant ceramic powders, the improvement which comprise said mixture consisting wholly or predominantly of eutectic microstructures selected from the group consisting of aluminum oxide/zirconium oxide, beryllium oxide/zirconium oxide, aluminum oxide/hafnium oxide, aluminum oxide/zirconium oxide/ytterbium oxide, aluminum oxide/hafnium oxide/yttrium oxide, aluminum oxide/hagnium oxide/ytterbium oxide, aluminum oxide/zirconium oxide/yttrium oxide, aluminum oxide/magnesium oxide/zirconium oxide, and aluminum oxide/magnesium oxide/hafnium oxide and wherein particles of zirconium oxide and hafnium oxide within the eutectic microstructures are in an extremely fine and homogenous distribution and are present to a substantial extent in a metastable tetragonal modification.
Dependencies are inferred from the claim text.