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2023
ACL
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J.Baborák, M.Yembele, P.Vařák, S.Ory, E.Véron, M.J.Pitcher, M.Allix, P.Nekvindová, A.Zandonà, 'Key melt properties for controlled synthesis of glass beads by aerodynamic levitation coupled to laser heating', Int J Appl Glass Sci. 14 455 (2023) doi:10.1111/ijag.16627
Binary alkali silicate glasseswere synthesized as beads by aerodynamic levitation
coupled to laser heating to test the applicability of the method to this compositional
range. While bubble-free lithium disilicate beads could be easily obtained,
sodium and potassium silicates proved more challenging to melt without significant
alkali evaporation: the final samples contained bubbles and exhibited
compositional drifts compared to the starting stoichiometry, especially at high
SiO2 content. The risk of volatilization fromthe melts was evaluated empirically:
the volatility of each oxide component scaled to the ratio between itsmelting temperature
Tm and the Tm of the target composition (revap), while the difference
between such ratios (Δevap) provided a qualitative estimation of the risk of differential
evaporation. The formulated approach enables to evaluate the suitability
of aerodynamic levitation synthesis for a given target glass composition: while
low melting temperature and low liquidus viscosity (η < 100 Pa s) represent the
primary optimal conditions,more viscous materials can still be preparedwithout
major compositional drifts using a more careful melting procedure, especially if
revap and Δevap are minimized.
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