关于举行法国国家科学研究中心Mathieu Allix研究员学术报告的通知

报告题目：Crystallization from Glass: Application to Transparent (Glass-)Ceramics

主 讲 人：Mathieu Allix 研究员

邀 请 人：周时凤 教授

报告时间：11月1号（星期三） 15:00-16:00

报告地点：北区科技园1号楼发光国重502会议室

欢迎广大师生踊跃参与~~~

报告摘要

Crystallization from glass can be a powerful process to elaborate innovating transparent materials for further optical applications if nucleation and crystal growth processes can be precisely controlled. This talk will focus on two main applications: transparent polycrystalline ceramics elaborated by full and congruent crystallization from glass and nanostructured glass-ceramics designed from nanoscale phase separated glasses.

Transparent polycrystalline ceramics elaborated by full crystallization from glass

Transparent ceramics are an emerging class of optical materials competing with single crystal technology for a broad range of applications. However, up to date, only a limited number of cubic or nanocrystalline transparent polycrystalline ceramics requiring complex and expensive synthetic approaches has been reported. Our recent work shows the possibility to obtain new transparent ceramics by full and congruent crystallization from glass.

Transparent nanostructured glass and glass-ceramics

New nanostructured gallogermanate- and gallosilicate-based glass materials exhibiting high transparency in the visible range have been synthesized by conventional melt-quenching. These materials can accommodate wide oxide compositions and present nanoscale phase separation. The size of the phase separation can be tailored depending on the nominal composition. A single heat treatment then allows selective crystallization of the phase separated glass, resulting in glass-ceramic materials exhibiting nanostructures and transparency similar to the parent glass. The wide possibilities of designing new nanostructured glass-ceramics with tunable optical properties will be illustrated in the case of a highly transparent ZnGa2O4 glass-ceramic exhibiting 50 wt% of nanocrystals with homogeneous and tunable sizes. Recently, glass-ceramic fibers have been developed from this composition.