Glass-ceramics one-step crystallization accomplished by building Ca2+ and Mg2+ fast diffusion layer around diopside crystal

The influence of Na2O on the fast diffusion layer around diopside crystals

“…In a previous study, 18 the activation energy of CMSglass ceramics with 0 mol Na + was found to be 301.2 kJ mol À1 . The activation energy of the 0.1 mol Na + added sample was 195.4 kJ mol À1 .…”

“…In Yang's study, the melts contained an excess of alkali metal ions. 18 During crystallization, the excess alkali metal ions lead to increasing amounts of Si-O-Na bonds in the residual glass phase, which result in an increase in the diffusion coefficients and the formation of a fast diffusion layer.…”

“…19,20 Yang and co-authors described a phenomenon in which the diffusion limiting layers become a fast diffusion layer. 18 By adding excess Na 2 O and CaF 2 , a fast diffusion layer was formed around the crystals to help increase the diffusion coefficient of the crystal phase ions. Thus, the crystal growth was accelerated.…”

“…Nevertheless, studies on the effect of the Na + content in the diffusion layer are rarely reported. 18 In this study, an excess of Na 2 O was added in the CMS system. During crystallization, Na + was considered as a glass modier, which forms the diffusion layer.…”