Richterite glass-ceramics

It is relatively easy to apply a glaze to these materials, as richterite glass-ceramics exhibit a high coefficient of thermal expansion of 115 x 10 (0°(D-300°C) due to the formation of a cristobalite secondary phase. Therefore, a glaze with a lower coefficient of thermal expansion can be applied to produce compressive strain in the surface of the material. As a result, the material is strengthened as described in Section 2.3.3. 

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