Claims
- 1. A method for molding ceramic powders, comprising:
- (a) forming a slurry mixture comprising ceramic powder, a dispersant for said ceramic powder, and a monomer solution consisting essentially of trimethylol propane triacrylate monomer, hexane-dioldiacrylate monomer, a free-radical initiator compound and an organic solvent;
- (b) transferring said slurry mixture into a mold;
- (c) heating said mold containing said slurry mixture at a temperature of about 100.degree. to 120.degree. C. for at least 5 minutes to cause said monomers to polymerize and crosslink to form a firm polymer-solvent gel matrix, whereby said slurry mixture is formed into a solid, shaped product;
- (d) removing said solid, shaped product from said mold;
- (e) heating said solid, shaped product at a temperature greater than about 130.degree. C. for about 2 to 6 hours to substantially remove said organic solvent from said product; and
- (f) further heating said solid, shaped product at a temperature greater than about 500.degree. C. for a time sufficient to substantially remove said polymer from said product.
- 2. A method as defined by claim 1, wherein the monomer solution comprises from about 10 to about 50 volume percent multifunctional monomers.
- 3. A method as defined by claim 1, wherein the ceramic powder is selected from the group consisting of alumina, fused silica, magnesia, zirconia, spinels, mullite, glass frits, tungsten carbide, silicon carbide, boron nitride and silicon nitride powders, and mixtures thereof.
- 4. A method as defined by claim 2 wherein the organic solvent is selected from a group consisting of phthalate esters, dibasic esters, high-boiling point petroleum solvents, long chain alcohols, and pyrollidones.
- 5. The method of claim 1 wherein said free-radical initiator compound is selected from the group consisting of organic peroxides and hydroperoxides, and azo and diazo compounds.
- 6. A method for molding ceramic powders, comprising:
- forming a slurry mixture comprising ceramic powder, a dispersant for said ceramic powder and a monomer solution, said monomer solution consisting essentially of
- (a) trimethylol propane triacrylate monomer
- (b) hexane-dioldiacrylate monomer
- (c) a free-radial initiator compound selected from the group consisting of organic peroxides and hydroperoxides, and azo and diazo compounds, and
- (d) an organic solvent selected from the group consisting of phathalate esters, dibasic esters, high-boiling point petroleum solvents, long chain alcohols and pyrollidones,
- said monomers being from about 10 to 50 volume percent in said monomer solution;
- transferring said slurry mixture into a mold;
- heating said mold containing said slurry mixture at a temperature of about 110.degree. C. for about 8 to 15 minutes to cause said monomers to polymerize and crosslink to form a firm polymer-solvent gel matrix, whereby said slurry mixture is formed into a solid, shaped product;
- removing said solid, shaped product from said mold;
- heating said solid, shaped product at a temperature greater than about 130.degree. C. for about 2 to 6 hours to substantially remove said organic solvent from said product; and
- further heating said solid, shaped product at a temperature greater than about 500.degree. C. for a time sufficient to substantially remove said polymer from said product.
Government Interests
The U.S. Government has rights in this invention pursuant to blanket purchase agreement No. DE AC05-840R21400 awarded by U.S. Department of Energy Contract with Martin Marietta Energy Systems, Inc.
US Referenced Citations (10)
Foreign Referenced Citations (1)
Number |
Date |
Country |
54-21413 |
Feb 1979 |
JPX |
Non-Patent Literature Citations (1)
Entry |
Cullen, F. M. et al, Forming Precision Shapes from Powdered Materials, IBM Technical Disclosure Bulletin, vol. 14, No. 10, Mar. 1972. |