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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 21: Glasses and Glass Transition 2 (joint session DY/CPP)

CPP 21.3: Vortrag

Mittwoch, 24. März 2021, 11:40–12:00, DYc

X-ray computed tomography of glass foams with tailored hierarchical pore structure — •Cristine Santos de Oliveira¹, Richard Kohns², Felix Meyerhoefer², Simon Carstens², Dirk Enke², Ralf Boris Wehrspohn^1,3, and Juliana Martins de Souza e Silva¹ — ¹Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany — ²Institut für Technische Chemie, Universität Leipzig, Germany — ³Fraunhofer Gesellschaft, München, Germany

Glass foams are materials consisting of a light-weight porous glass structure of special importance in the fields of civil engineering and bio-implants. Typically, their synthesis involves the thermal foaming of a powder mixture of glass with a foaming agent that decomposes at the foaming temperature, resulting in a solid glass skeleton permeated by empty pores. In our work, we synthesized a series of glass foams with a hierarchical pore structure, obtained by combining pores generated through the foaming of a powdered mixture of silica-based glass, MnO₂ and C at 815 ^∘C, with pores obtained by phase-separation (performed at circa 500 ^∘C) followed by acid leaching and washing. Using a combination of mercury intrusion porosimetry, N₂ sorption and X-ray CT at the micro and nanometer scales we observed that slight changes in the preparation procedure resulted in foams with different porosity, surface area, pore size and pore volume. Furthermore, by applying machine learning segmentation to the X-ray CT data it was possible to map inhomogeneities, residues and cracks inside the foam walls.