Modified cordierite precursors
US5409870A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1992 |
| Grant date | Apr 25, 1995 |
| Priority date | — |
| Expiry date | Nov 20, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02A50/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Cordierite-containing articles are produced by a method comprising the steps of providing raw materials including including alumina-yielding ingredients, magnesia-yielding ingredients, and silica-yielding ingredients, suitable to form an analytical batch composition by weight on an oxide basis of 9-20 weight percent MgO, 30-50 weight percent Al.sub.2 O.sub.3, and 41-56.5 weight percent SiO.sub.2. The raw materials include talc having a BET surface area of no greater than about 4.0 m.sup.2 /g, and uncalcined clay having an average particle size of no greater than about 2.0 .mu.m. The raw materials are blended with an effective amount of vehicle and forming aids to form a plastic mixture. The plastic mixture is anisostatically formed into a green body and dried. The dried green body is fired at a temperature and for a time effective to form a cordierite/containing ceramic article. The cordierite-containing articles exhibit a coefficient of thermal expansion of not greater than about 4.0.times.10.sup.-7 /.degree.C. and transverse I ratios of not less than about 0.85. The method of the present invention is particularly useful in forming cordierite honeycomb structures used as catalyst …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.