Nucleation and growth of hexagonal CaAl2Si2O8 crystals in CaO-Al2O3-SiO2 glass

摘要

Hexagonal CaAl2Si2O8 was precipitated inside of 25Ca0O-20Al(2)O(3)-55SiO(2) (wt%) glass by heat treatment at 1050 degrees C with MoO3 and carbon as nucleating agents. Transmission electron microscopy revealed that metallic molybdenum particles with sizes of similar to 200 nm precipitated in the glass and served as heterogeneous nucleation sites for plane-like hexagonal CaAl2Si2O8 crystals with widths greater than 10 mu m and thicknesses of similar to 1 gm. The thickness direction was the c-axis of hexagonal CaAl2Si2O8. (C) 2017 Elsevier B.V. All rights reserved.