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Patent US4634685A successfully refreshed from Google Patents.
US4634685A
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Refractory article suitable for casting molten metal
Assignee: Didier Werke AG
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Filing: 1985-10-31
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Granted: 1987-01-06
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Expires: 2005-10-31
Abstract
Abstract A refractory article for casting of liquid melts, especially steel, fabricated from a mixture of Al 2 O 3 , graphite, a flux component, a synthetic resin binder and a metallic powder. The flux component contains a first flux with a melting point from 550° to 900° C. and a second flux that becomes active in the mixture in a temperature ranging from 1350° and 1550° C. The refractory article need not be heated before use, and the carbon contained therein, which determines the strength of the article, is retained for a much longer period during use, so that the article will have a long service life.
Inventors
- 👤 Siegfried Pohl
- 👤 Ernst Luhrsen
- 👤 Peter Jeschke
- 👤 Ortwin Rave
- 👤 Martin Kienow
- 👤 Werner Richter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:02
CPC Classifications
B; B22; B22D; B22D41/00; B22D41/50; B22D41/52; B22D41/54; C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/101
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
94 words
A refractory article suitable for casting molten metal, which comprises, based on the weight of said article: 30 to 64% of Al 2 O 3 ; 20 to 40% of graphite; 10 to 20% of a synthetic resin; 1 to 8% of a metallic powder; and 4 to 20% of a flux component comprising a first flux having a melting point of 550° to 900° C. and a second flux having a melting point of 1350° to 1550° C., the weight ratio of said first flux to said second flux being 2:1 to 1:15.
Claim 2
Dependent Claim
94 words
A refractory article suitable for casting molten metal, which comprises, based on the weight of said article: 30 to 64% of Al 2 O 3 ; 20 to 40% of graphite; 10 to 20% of a synthetic resin; 1 to 8% of a metallic powder; and 4 to 20% of a flux component comprising a first flux having a melting point of 550° to 900° C. and a second flux having a melting point of 1350° to 1550° C., the weight ratio of said first flux to said second flux being 2:1 to 1:15.
Claim 3
Dependent Claim
32 words
A refractory article according to claim 1, which further comprises a raw glaze on at least a portion of the total surface area of said article to inhibit oxidation of said article.
Claim 4
Dependent Claim
15 words
A refractory article according to claim 1, wherein said first flux is a boron-containing flux.
Claim 5
Dependent Claim
24 words
A refractory article according to claim 3, wherein said boron-containing flux is selected from the group consisting of boric acid, borax and boron frit.
Claim 6
Dependent Claim
50 words
A refractory article according to claim 1, wherein said second flux is selected from the group consisting of a feldspar, a glass frit, a mixture of a feldspar and ZrO 2 , a mixture of a feldspar and ZrSiO 4 , and a mixture of a feldspar and aluminum oxide.
Claim 7
Dependent Claim
16 words
A refractory article according to claim 1, wherein said second flux is an alkali metal feldspar.
Claim 8
Dependent Claim
20 words
A refractory article according to claim 1, wherein said metallic powder is a powder of silicon, aluminium or ferro silicon.
Claim 9
Dependent Claim
16 words
A refractory article according to claim 7, wherein said metallic powder is a powder of silicon.
Claim 10
Dependent Claim
27 words
A refractory article according to claim 1, wherein said synthetic resin is selected from the group consisting of a liquid epoxy resin and a liquid phenolic resin.
Claim 11
Dependent Claim
48 words
A refractory article according to claim 1, which comprises 40 to 55% of said Al 2 O 3 , 20 to 30% of said graphite, 12 to 18% of said synthetic resin, 2 to 6% of said refractory metallic powder, and 8 to 15% of said flux component.
Claim 12
Dependent Claim
23 words
A refractory article according to claim 10, wherein the weight ratio of said first flux to said second flux is 1:1 to 1:10.
Claim 13
Dependent Claim
15 words
A refractory article according to claim 11, wherein said weight ratio is 1:3 to 1:8.
Claim 14
Dependent Claim
163 words
A process for producing a refractory article suitable for casting molten metal, which article comprises, based on the weight of said article, 30 to 64% of Al 2 O 3 , 20 to 40% of graphite, 10 to 20% of a synthetic resin, 1 to 8% of a metallic powder, and 4 to 20% of a flux component comprising a first flux having a melting point of 550° to 900° C. and a second flux having a melting point of 1350° to 1550° C., the weight ratio of said first flux to said second flux being 2:1 to 1:15, said process comprising the steps of: providing a mixture containing said amounts of said Al 2 O 3 , graphite, synthetic resin, metallic powder and flux component; molding said mixture; annealing the molded mixture to cure said synthetic resin; and heat-treating the annealed article at a temperature of up to 1000° C. which is sufficient to melt said first flux, in a non-oxidizing atmosphere.
Claim 15
Dependent Claim
163 words
A process for producing a refractory article suitable for casting molten metal, which article comprises, based on the weight of said article, 30 to 64% of Al 2 O 3 , 20 to 40% of graphite, 10 to 20% of a synthetic resin, 1 to 8% of a metallic powder, and 4 to 20% of a flux component comprising a first flux having a melting point of 550° to 900° C. and a second flux having a melting point of 1350° to 1550° C., the weight ratio of said first flux to said second flux being 2:1 to 1:15, said process comprising the steps of: providing a mixture containing said amounts of said Al 2 O 3 , graphite, synthetic resin, metallic powder and flux component; molding said mixture; annealing the molded mixture to cure said synthetic resin; and heat-treating the annealed article at a temperature of up to 1000° C. which is sufficient to melt said first flux, in a non-oxidizing atmosphere.
Claim 16
Dependent Claim
29 words
A process according to claim 13, which further comprises applying a glaze to at least a portion of the total, surface area of the article after said heat-treating step.
Claim 17
Dependent Claim
22 words
A process according to claim 13, wherein said first and second fluxes are premixed with each other to prepare said flux component.
Claim 18
Dependent Claim
161 words
A refractory article suitable for casting molten metal, which is produced by a process comprising the steps of: providing a mixture which comprises, based on the weight of said mixture, 30 to 64% of Al 2 O 3 , 20 to 40% of graphite, 10 to 20% of a synthetic resin, 1 to 8% of a refractory metallic powder, and 4 to 20% of a flux component comprising a first flux having a melting point of 550° to 900° C. and a second flux having a melting point of 1350° to 1550° C., the weight ratio of said first flux to said second flux being 2:1 to 1:15; molding said mixture; annealing the molded mixture to cure said synthetic resin; heat-treating the annealed article at a temparature of up to 1000° C. which is sufficient to melt said first flux, in a non-oxidizing atmosphere; and subjecting the resultant article to a temperature of 900° to 1000° C. in an oxidizing atmosphere.
Claim 19
Dependent Claim
161 words
A refractory article suitable for casting molten metal, which is produced by a process comprising the steps of: providing a mixture which comprises, based on the weight of said mixture, 30 to 64% of Al 2 O 3 , 20 to 40% of graphite, 10 to 20% of a synthetic resin, 1 to 8% of a refractory metallic powder, and 4 to 20% of a flux component comprising a first flux having a melting point of 550° to 900° C. and a second flux having a melting point of 1350° to 1550° C., the weight ratio of said first flux to said second flux being 2:1 to 1:15; molding said mixture; annealing the molded mixture to cure said synthetic resin; heat-treating the annealed article at a temparature of up to 1000° C. which is sufficient to melt said first flux, in a non-oxidizing atmosphere; and subjecting the resultant article to a temperature of 900° to 1000° C. in an oxidizing atmosphere.
Claim 20
Dependent Claim
39 words
A refractory article according to claim 16, wherein the process further comprises applying a glaze to at least a portion of the total surface area of the article after said heat-treating step and before treatment in said oxidizing atmosphere.
References Cited (Backward Citations)
US3949803A
Cited
US3934637A
Cited
US3937269A
Cited
US4040469A
Cited
US4174226A
Cited
US4540675A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1990-01-05 | 1990-07-07 | 1991-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-05 | 1994-07-07 | 1995-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-05 | 1998-07-07 | 1999-01-06 | $7700.00 | Window Closed / Lapsed |