第7回フロンティア材料研究所講演会 (Eleonora Kulik)
| 開催日時 | 2016年06月30日 13:30 -14:00 |
|---|---|
| 開催場所 | Ｒ３棟１階 会議室 |
| 主催 | フロンティア材料研究所 |
| 連絡先 | 若井 史博 教授（内線:5361） |
プログラム等
講師： Eleonora Kulik
(Deutsches Elektronen-Synchrotron, Germany)
演題： "Thermal expansion of coesite: A synchrotron X-ray diffraction study from 100 K up to 1000 K"
講演概要:
Coesite is the densest silica polymorph in which silicon is tetrahedrally coordinated by oxygen .However, contrary to other low pressure forms of SiO2, coesite does not undergo α-β transition at least up to 1776 K, it also exhibit much lower thermal expansion than quartz and crystobalite. In this work high-temperature structural features of synthetic coesite and its behavior at the microscopic level have been investigated by X-ray powder diffraction . We observed that the thermal expansion of coesite is strongly anisotropic and negative along a c axis . It leads to a very low volume expansion by only 0.7% in the considered temperature range between 100 K and 1000 K. For the material research and ceramic industry the importance of such kind of materials is in their widespread use in high anti-thermal shock applications.
