Claims
- 1. A method for producing nitride bonded refractory bricks, in situ, comprising mixing, by weight, from about 1 to 25% aluminum, about 1 to 25% substantially pure silica and the balance a refractory brickmaking size graded refractory aggregate, selected from the group consisting of silicon carbide, fused mullite and deadburned magnesite, pressing said mixes into refractory bricks, burning the bricks at a first temperature in a nitriding atmosphere for a time sufficient to form silicon and reactive alumina, said temperature being less than the temperature level at which a sialon intergranular bond will form; further burning the bricks at a temperature exceeding the first temperature in a nitriding atmosphere to form silicon nitride from the previously formed silicon; and forming a sialon intergranular bond for the refractory brick by reacting the previously formed reactive alumina with the silicon nitride.
- 2. Method of claim 1 in which the aluminum comprises, by weight, about 1 to 16% and the substantially pure silica comprises, by weight, about 1.5 to 20% of the mix.
- 3. Method of claim 1 in which the first temperature at which the bricks are burned is approximately 800.degree. C. and the second temperature is at least 1250.degree. C.
- 4. Method of claim 1 in which the nitriding atmosphere is selected from the group consisting of gaseous nitrogen, industrial annealing gas and ammonia gas.
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of application Ser. No. 321,155 filed Nov. 13, 1981, now abandoned which is a divisional application of application Ser. No. 149,609 filed May 14, 1980, by Daniel R. Petrak, H. M. Winkelbauer, T. R. Kleeb and K. C. Wang, entitled "REFRACTORY" and now abandoned.
US Referenced Citations (3)
Divisions (1)
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Number |
Date |
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Parent |
149609 |
May 1980 |
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Continuation in Parts (1)
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Number |
Date |
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321155 |
Nov 1981 |
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