Bestimmung der Randbedingungen vorherrschender Phasentrennprozesse in Boratglas Systemen
Zusammenfassung der Projektergebnisse
Glass-forming regions of systems ZrO₂–Na₂O–B₂O₃, CeO₂–Na₂O–B₂O₃, and selected glasses from system ZrO₂–CeO₂–Na₂O–B₂O₃ were investigated. ZrO₂ acts as an intermediate oxide, while CeO₂ functions as a network participant or modifier depending on R-value and concentration. High CeO₂ contents lead to formation of a dual network of cerium and sodium borate-rich phases, significantly influencing glass transformation temperature (T g) and molare volume (Vm ). All glasses exhibited phase separation after melting. Inter connecting glassy microstructures were identified in CeO₂–Na₂O–B₂O₃ and ZrO₂–CeO₂–Na₂O–B₂O₃ glasses. Heat treatments with Avrami coefficient between 0.5 and 1 promoted domain growth of glassy phases while crystallization remained low (< 5 wt.%). Selective leaching in water completely removed Na₂O and mostly removed B₂O₃; the network of CeO₂ and optional ZrO₂ remained unchanged. This confirmed the hypothesis that phase separation can be isolated from crystallization to obtain an interconnected, leachable microstructure. This approach enabled fabrication of porous, silica-free glasses.
Projektbezogene Publikationen (Auswahl)
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"Subtraction Method's Potential to Produce Porous Silicate-Free Glass Ceramics," ICG Berlin, presentation
Koppka, Sharon
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"Advancements in Selective Laser Sintering of Controlled Porous Glasses," MSE Jahrestagung
Koppka, Sharon
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"Impact of Selective Laser Sintering on the Production of Nano Porous SiO ₂ and CeO₂ Glass Ceramics," DGG Jahrestagung
Koppka, Sharon
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"Development of Porous Glasses and Glass Ceramics," 4th Symposium for Glass Apparatus Builders
Koppka, Sharon
