Surface Crystallization of Fresnoite from a Glass Studied by Hot Stage Scanning Electron Microscopy and Electron Backscatter Diffraction

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• 作者：Wolfgang Wisniewski ; Christian Bocker ; Maher Kouli ; Markus Nagel ; Christian R眉ssel
• 刊名：Crystal Growth & Design
• 出版年：2013
• 出版时间：August 7, 2013
• 年：2013
• 卷：13
• 期：8
• 页码：3794-3800
• 全文大小：417K
• 年卷期：v.13,no.8(August 7, 2013)
• ISSN：1528-7505

文摘

Polished pieces of a glass with the composition 2BaO路TiO₂路2.75SiO₂ (fresnoite + 0.75SiO₂) were annealed at 790鈥?70 掳C and subsequently analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM) including electron backscatter diffraction (EBSD). Surface morphologies and textures of samples annealed in a normal furnace are presented. While the texture of oriented nucleation occurs over the entire temperature range, the development of previously undetected secondary textures is described and explained. In-situ high temperature video sequences visualize the growth and a two-step nucleation of fresnoite. The velocity of crystal growth along the surface in the vacuum is measured and compared to the mean velocity of three-dimensional crystal growth in an ambient atmosphere. For example, growth velocities along the surface reach 3.6 渭m/min in the vacuum at 830 掳C compared to 0.16 渭m/min during growth into the bulk.