• Treffer 1 von 5
Zurück zur Trefferliste

Crack healing in glasses and glass matrix composites

  • Fundamental understanding of crack healing in glassy crystalline materials is very important for many applications, especially for sealing solid oxide fuel cells (SOFC) since cracks caused by sealing or thermal cycling still remain a substantial bottleneck in developing durable SOFC. Previous studies on soda lime silicate glass [Sin14] showed that crack healing is driven by viscous flow and that healing progress is proportional to time t and inverse viscosity η. This finding would allow to present healing data of a given glass for different temperatures in a master curve healing progress versus t/η. Such master curves would be a helpful tool in understanding crack healing kinetics. Against this background, crack healing in non-crystallizing sodium calcium silicate (NCS) and sodium borosilicate glasses (NBS) have been studied. Moreover, to evaluate the influence of micros structure in crystallized glass on crack healing process, glass matrix composites (GMC) where prepared out ofFundamental understanding of crack healing in glassy crystalline materials is very important for many applications, especially for sealing solid oxide fuel cells (SOFC) since cracks caused by sealing or thermal cycling still remain a substantial bottleneck in developing durable SOFC. Previous studies on soda lime silicate glass [Sin14] showed that crack healing is driven by viscous flow and that healing progress is proportional to time t and inverse viscosity η. This finding would allow to present healing data of a given glass for different temperatures in a master curve healing progress versus t/η. Such master curves would be a helpful tool in understanding crack healing kinetics. Against this background, crack healing in non-crystallizing sodium calcium silicate (NCS) and sodium borosilicate glasses (NBS) have been studied. Moreover, to evaluate the influence of micros structure in crystallized glass on crack healing process, glass matrix composites (GMC) where prepared out of NCS and zirconia as inert ceramic filler material mimicking a partially crystalline micro structure. Cracks were generated by Vickers indention and healed isothermally at different temperatures. Crack healing progress was monitored by optical and electron microscopy. Results show that the above mentioned proportionality actually applies for the studied glasses for which such a master curve could be obtained. In comparison to a non-crystallized glass, the effective viscosity of GMC is increased by rigid filler content. This effect substantially retards crack broadening during later healing stages, which often ends up in large pores. On the other hand, local viscous crack healing is still possible in larger glassy regions. This behavior seems to be very interesting for crack healing optimized sealants.zeige mehrzeige weniger

Volltext Dateien herunterladen

  • Vortrag Crack healing in glasses and glass matrix composites - Weimar 2017.pdf
    eng

Metadaten exportieren

Weitere Dienste

Teilen auf Twitter Suche bei Google Scholar
Metadaten
Autoren/innen:Carsten Blaeß
Koautoren/innen:Ralf Müller, Cyrus Thompson
Dokumenttyp:Vortrag
Veröffentlichungsform:Präsentation
Sprache:Englisch
Jahr der Erstveröffentlichung:2017
Organisationseinheit der BAM:5 Werkstofftechnik
5 Werkstofftechnik / 5.6 Glas
DDC-Klassifikation:Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften
Freie Schlagwörter:Composite; Crack healing; Glass; Glass ceramic
Themenfelder/Aktivitätsfelder der BAM:Material
Veranstaltung:91. Jahrestagung HVG-DGG
Veranstaltungsort:Weimar, Germany
Beginndatum der Veranstaltung:29.05.2017
Enddatum der Veranstaltung:31.05.2017
Verfügbarkeit des Dokuments:Datei im Netzwerk der BAM verfügbar ("Closed Access")
Datum der Freischaltung:15.08.2017
Referierte Publikation:Nein