Crystallization of Al2O3-SiO2 gels in water at 473 K.

Investigation of crystallization and sinterability properties of BaO-Al2O3-SiO2 glass-ceramics containing K2O and B2O3

BaO -SiO2-Al2O3 glass ceramics containing K2O and B2O3 were prepared using conventional melting of powered batches, quenching in water and crystallization of sintered glass. XRD patterns introducehexacelsian and celsian as two major crystallized phases in sintered glass-ceramics. Presence of K2O enhances crystallization of hexacelsianin comparison withB2O3.Observations showed sintering temperat...

CRYSTALLIZATION BEHAVIOUR OF GELS AND GEL-MONOLITHS IN THE Na2O-B2O3-SiO2 SYSTEM

Synthesis of Nanoscale CaO-Al2O3-SiO2-H2O and Na2O-Al2O3-SiO2-H2O Using the Hydrothermal Method and Their Characterization

C-A-S-H (CaO-Al₂O₃-SiO₂-H₂O) and N-A-S-H (Na₂O-Al₂O₃-SiO₂-H₂O) have a wide range of chemical compositions and structures and are difficult to separate from alkali-activated materials. Therefore, it is difficult to analyze their microscopic properties directly. This paper reports research on the synthesis of C-A-S-H and N-A-S-H particles with an average particle size smaller than 300 nm by apply...

Surface Crystallization of a MgO/Y2O3/SiO2/Al2O3/ZrO2 Glass: Growth of an Oriented β-Y2Si2O7 Layer and Epitaxial ZrO2

The crystallization behavior of a glass with the composition 54.7 SiO2·10.9 Al2O3·15.0 MgO·3.4 ZrO2·16.0 Y2O3 is studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) including electron backscatter diffraction (EBSD) and (scanning) transmission electron microscopy [(S)TEM] including energy-dispersive X-ray spectrometry (EDXS). This glass shows the sole surface crystallizatio...

Solubility of corundum in the system Al2O3–SiO2–H2O–NaCl at 800 °C and 10 kbar

The solubility of corundum was measured at 800 °C and 10 kbar in NaCl–H2O–SiO2 fluids over NaCl mole fractions (XNaCl) of 0 to 0.5 and SiO2 concentrations of zero to quartz or albite+melt saturation, depending on XNaCl. Experiments were performed in a piston-cylinder apparatus. Dissolved Al2O3 and SiO2 were determined by weight losses of corundum and quartz crystals, or by bulk compositions of ...