Process for durable sol-gel produced alumina-based ceramics, abrasive grain and abrasive products
AssigneeMinnesota Mining and Manufacturing Company
InventorMark G. Schwabel
Life of this patent
Estimating the term…
Abstract
A sol-gel process of producing durable alpha alumina-based ceramic particularly useful as abrasive grain from alpha alumina monohydrate is improved by the addition of a nucleating agent. Improved abrasive products containing the durable ceramic abrasive grains are also provided.
Claims42
In the sol-gel process for forming alumina-based ceramic, the process comprising:
- a. preparing a dispersion of alpha alumina monohydrate particles;
- b. gelling the dispersion;
- c. drying the gel dispersion to form a solid;
- d. calcining the solid;
- and
- e. sintering the calcined solid, the improvement comprising introducing nucleating agents into the dispersion before the drying step by adding to the dispersion a nucleating agent selected from the group consisting of a precursor of alpha ferric oxide and alpha ferric oxide.
Alumina-based sol-gel ceramic comprising alpha alumina having alpha ferric oxide nucleating material dispersed therein.
The alumina-based sol-gel ceramic consisting essentially of alpha alumina having alpha ferric oxide nucleating material dispersed therein.
Abrasive grain comprising alumina-based sol-gel ceramic comprising alpha alumina having alpha ferric oxide nucleating material dispersed therein.
An abrasive article comprising abrasive grain at least a portion of which comprises sol-gel abrasive grain comprising alpha alumina having alpha ferric oxide nucleating material dispersed therein.
An abrasive article comprising abrasive grain at least a portion of which comprises sol-gel abrasive grain consisting essentially of alpha alumina having alpha ferric oxide nucleating material dispersed therein.
Alumina-based sol-gel ceramic comprising alpha alumina substantially in the form of domains which contain a nucleating amount of alpha ferric oxide and have an average diameter of less than about 5 micrometers.
Abrasive grain comprising alumina-based sol-gel ceramic comprising alpha alumina substantially in the form of domains which contain a nucleating amount of alpha ferric oxide and have an average diameter of less than about 5 micrometers.
Dependencies are inferred from the claim text.