The Formation of a New Phase during Crystallization of TiO₂-Doped Nd₂O₃-Al₂O₃-SiO₂ Glasses

Abstract

Glasses with the general compositions xNd ₂O₃.20Al₂O₃.(80–x)SiO₂ and 15Nd₂O₃.yAl₂O₃.(85–y)SiO₂ (x = 10, 15, 20, and y = 20, 25, 30) were prepared by melting at 1550°C. The glasses also contained varying amounts of TiO₂ as nucleating agent. The microstructural evolution of the undoped and TiO₂-containing glass-ceramics was then studied. Crystallization of the glasses was feasible in the range 1000° to 1250°C. The crystallization rates were evaluated. TiO₂ addition influenced only the growth rate and not the nucleation of the crystalline phases observed in this study. Glasses of higher SiO₂ content showed a rise in growth rate. It was found that when TiO₂ was present, a new unreported crystalline compound with the stoichiometric composition of TiO₂.Nd₂O₃.Al₂O₃.2SiO₂ was formed

GRAPHICAL ABSTRACT

Keywords:

• Rare earth oxides
• Glass-ceramics
• Crystallization
• Nucleating agent