Structure and viscosity of CaO–Al ₂ O ₃ –B ₂ O ₃ –BaO slags with varying mass ratio of BaO to CaO

The structure of CaO–Al2O3–B2O3–BaO glassy slags with varying mass ratio BaO to CaO has been investigated by Raman spectroscopy, 11B and 27Al magic angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopy atomic pair distribution function (PDF). MAS-NMR spectra reveal the dominant coordination boron as trigonal. Both simulations on indicate presence orthoborate primary borate group a few groups one bridging oxygen minor four-coordinated sites. PDF show Al tetrahedral. spectral study shows that transverse vibration AlIV–O–AlIV AlIV–O–BIII, stretching aluminate structural units pyroborate groups. A broader Al–O bond lengths in also supports enhanced network connectivity. Viscosity measurements increase viscosity molten increasing CaO, which further attributes degree polymerization network.