摘要 |
In a method of forming a refractory product wherein a mixture consisting of effective amounts of silica, alumina, aluminium nitride, and with or without silicon nitride, is provided, the mixture is surrounded with a protective medium and sintered at a temperature between 1200 DEG -2000 DEG C to form a single phase silicon aluminium oxynitride corresponding to the formula: Si6-zAlzN8-zOz, where z is greater than zero and less than or equal to 5, and when there is no silicon nitride in the mixture z is greater than or equal to 4 and less than or equal to 5, the improvement being the step of introducing into said mixture magnesium oxide in an amount of not more than 5% by weight to form a magnesium silicate glass and aid in densification of the ceramic material.
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