摘要 |
A binder/suspension liquid for use with refractory compounds and the like. Oxidation prevention coatings for up to at least 1000 degrees Centigrade are described. Both a graphite non-conductive and a conductive coating are described for use in coating graphite crucibles, graphite electrodes, and the like. Typical compositions utilize a binder/suspension liquid phase in an amount from about 40 to about 55 wt. % of the total paintable mixture. This binder/suspension liquid phase is formed by intimately mixing colloidal silica solution, mono-aluminum phosphate solution and alcohol. The non-conducting embodiment of the graphite coating is produced by mixing finely divided boric acid and silicon carbide with the binder/suspension liquid phase. The preferred conductive coating substitutes a mixed TiC-SiC for the SiC of the non-conductive embodiment. The resultant material is very stable (i.e., does not settle), is paintable upon the graphite, and is easily dried at or near room temperature. A few thin coats, with drying between applications, totaling only about 0.15 to about 0.23 mm prevents detrimental oxidation through several cycles to at least 1000 degrees C. Other applications of the binder/suspension agent are discussed.
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