Time-temperature-transformation diagrams for for borosilicate glasses and preparation of chemically durable porous glasses

摘要

To clarify the effects of glass composition and heat-treatment conditions on phase separation and crystallization, time- temperature-transformation (TTT) diagrams for the sys- tem (65-x)SiO_2.25B_2O_3.(10-y)Na_2O._yCaO_xZrO_2, which is used for fabricating alkali-durable porous glasses, were determined. The microstructures and properties, such as resistance to alkaline attack as a function of ZrO_2 content, of the porous glasses fabricated on the basis of the devel- oped TTT diagrams were examined.