Effect of the concentrations of nucleating agents ZrO2 and TiO2 on the crystallization of Li2O-Al2O3-SiO2 glass: an X-ray diffraction and TEM investigation

Effect of the concentrations of nucleating agents ZrO2 and TiO2 on the crystallization of Li2O-Al2O3-SiO2 glass: an X-ray diffraction and TEM investigation

In order to study the effect of ZrO2 and TiO2 on the nucleation mechanism in a lithium aluminosilicate glass, a composition similar to that of the commercially available ROBAX (TM) glass (Schott AG) was modified. Glasses with different concentrations of ZrO2 and TiO2 were melted and studied using differential scanning calorimetry measurement. The glasses are thermally treated for different periods of time and at various temperatures and then investigated by X-ray diffraction and electron microscopy. Both scanning electron microscopy and transmission electron microscopy were applied to study size and shape of the formed crystal phases and possibly to obtain lattice plane distances. Increasing the concentration of the nucleation agents led to the spontaneous formation of Zr1-x Ti1+x O-4 nano crystals during cooling. In any case, the nuclei contain much more titania than zirconia, possess an elongated shape, and are embedded in a shell enriched in alumina.

为了研究二氧化锆（ZrO₂）和二氧化钛（TiO₂）对铝硅酸锂玻璃成核机制的影响，对一种与市售的ROBAX™玻璃（肖特公司）成分相似的物质进行了改性。将含有不同浓度ZrO₂和TiO₂的玻璃熔化，并利用差示扫描量热法进行研究。这些玻璃在不同的时间和温度下进行热处理，然后通过X射线衍射和电子显微镜进行研究。扫描电子显微镜和透射电子显微镜都被用于研究所形成晶相的大小和形状，并可能获取晶格平面间距。成核剂浓度的增加导致在冷却过程中Zr₁₋ₓTi₁₊ₓO₄纳米晶体的自发形成。在任何情况下，晶核中所含的二氧化钛都比二氧化锆多得多，呈细长形状，并嵌在富含氧化铝的壳层中。