초록 ▼

A thermal shock-resistant ceramic article and a method of manufacturing the article include alternating layers of a first material (2) comprising a fusible, particulate ceramic composition and a second material (3), typically comprising a porous, pyrolyzable material. The layered structure increases

A thermal shock-resistant ceramic article and a method of manufacturing the article include alternating layers of a first material (2) comprising a fusible, particulate ceramic composition and a second material (3), typically comprising a porous, pyrolyzable material. The layered structure increases the article's work of fracture and toughness, and may lead to improved thermal shock-resistance. The method advantageously uses a sheet, film or sleeve to prepare the article for firing. The composition, thickness, and porosity of the second material (3) will affect the desired properties. The method is particularly adapted for manufacturing cylindrical articles, including stopper rods, nozzles, and pouring tubes for the metal casting industry.

대표청구항 ▼

1. A method for producing an article for use with molten metal, comprising: a) filling a flexible sleeve with a fusible, particulate ceramic composition; b) compacting the filled sleeve; c) layering a plurality of compacted sleeves to form a piece; d) pressing the piece; and e) firing the pie

1. A method for producing an article for use with molten metal, comprising: a) filling a flexible sleeve with a fusible, particulate ceramic composition; b) compacting the filled sleeve; c) layering a plurality of compacted sleeves to form a piece; d) pressing the piece; and e) firing the piece at a temperature sufficient to fuse the ceramic composition. 2. The method of claim 1, wherein the sleeve comprises a combustible material. 3. The method of claim 2, the combustible material is comprised of a material selected from the group consisting of natural and synthetic polymers. 4. The method of claim 1, wherein the sleeve is porous. 5. The method of claim 1, wherein pressing is accomplished by isostatic pressing. 6. The method of the compacted sleeve has a thickness between about 0.05 mm and about 10 mm. 7. The method of claim 1, wherein the sleeve is sequentially filled with at least two different ceramic compositions. 8. The method of claim 1, wherein layering comprises rolling the compacted sleeve on itself. 9. The method of claim 1, wherein layering comprises rolling the compacted sleeve around a mandrel. 10. A method for producing an article for use with molten metal, comprising: a) filling a flexible, porous sleeve with a fusible, particulate ceramic composition; b) compacting the filled sleeve; c) wrapping the filled sleeve around a mandrel to form a piece; d) isostatically pressing the piece; and e) firing the piece at a temperature sufficient to fuse the ceramic composition. 11. A method of making a refractory article having a plurality of layers and adapted for channeling a stream of molten metal, the method comprising: a) producing a first layer comprising a first fusible, particulate ceramic composition having a thickness between about 0.05 mm and about 20 mm and a porous sheet having a thickness between about 0.005 mm and about 2.0 mm; b) depositing onto the porous sheet a second layer comprising a second fusible, particulate ceramic composition having a thickness between about 0.05 mm and about 20 mm; c) pressing the layers together so that the first fusible, particulate ceramic composition contacts the second fusible, particulate ceramic composition through the porous sheet, thereby forming a piece; and d) firing the piece at a temperature sufficient to fuse the first and second ceramic compositions, thereby making the article. 12. The method of claim 11, wherein the method includes compacting the first layer before depositing the second layer. 13. The method of claim 11, wherein the first ceramic composition differs from the second ceramic composition. 14. The method of claim 11, wherein the sheet comprises a combustible material. 15. A method for producing a refractory article having a plurality of layers and adapted for channeling a stream of molten metal, comprising: a) producing a layer comprising a first, fusible, particulate ceramic composition having a thickness between about 0.05 and about 10 mm and a porous sheet having a thickness between about 0.005 mm and about 1 mm b) compacting at least a portion of the layer; c) spiraling the layer about a central axis, whereby a plurality of spiraled layers spiral outward from the central axis d) pressing the spiraled layers so that the ceramic composition on a spiraled layer contacts the ceramic composition of an adjacent spiraled layer through the porous sheet, thereby forming a piece; and e) firing the piece at a temperature sufficient to fuse the ceramic compositions, thereby making the article. 16. The method of claim 15, wherein the central axis is occupied by a mandrel. 17. The method of claim 15, wherein pressing is accomplished by isostatic pressing. 18. The method of claim 15, wherein the a first spiraled layer includes a first ceramic composition and a second spiraled layer includes a second ceramic composition. 19. The method of claim 15, wherein the sheet comprises a combustible material.