Preparation of b-quartz glass-ceramics and / or b-spodumene, of articles made from said glass-ceramics; glass ceramics, items made of said glass-ceramics and precursor glasses.

摘要

A method of preparing a glass-ceramic containing a solid solution of β-quartz or of β-spodumene (solid solutions of β-quartz and β-spodumene), as phase (s) crystal (s) main (s), comprising heat treating a glass of lithium aluminosilicate is a precursor of said glass-ceramic, under conditions ensuring its ceramming, characterized in that said glass jointly contains, as fining agent: - fluorine, in an amount of between 0.1 and 2% by weight; and - at least one oxide of a multivalent element selected from SnO2, V2O5 and MnO2, in an amount of between 0.2% and 2% by weight; SnO2 being incorporated at no more than 0.7% by weight, advantageously incorporated in not more than 0.5% by weight.