Fabrication of ultra low thermal expansion cordierite structures
US6284693A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1999 |
| Grant date | Sep 4, 2001 |
| Priority date | — |
| Expiry date | Nov 30, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24149
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Disclosed is sintered ceramic article that exhibits a primary crystalline phase of cordierite and analytical oxide composition, in weight percent, of 49-53% SiO.sub.2, 33-38% Al.sub.2 O.sub.3, 12-16% MgO and exhibits a coefficient of thermal expansion no greater than about 4.0.times.10.sup.-7 /.degree. C. over the temperature range of about 25.degree. C. to about 800.degree. C. and a transverse-I ratio of not less than about 0.92. Also disclosed is a method for producing a sintered cordierite ceramic article involving preparing a plasticizable raw material, comprising a magnesium source, a SiO.sub.2 -forming source and an additional component of either: (a) a clay-free, Al.sub.2 O.sub.3 -forming source having a surface area of greater than about 5 m.sup.2 /g; or, (b) a clay and Al.sub.2 O.sub.3 -forming source combination wherein the clay comprises no greater than about 30%, by weight, of the total inorganic mixture, and the Al.sub.2 O.sub.3 -forming source exhibits a surface area of greater than about 40 m.sup.2 /g. The mixture is formed into a green body substrate of the desired configuration and subsequently dried and fired for a time and at temperature sufficient to form a stru…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.