大型放射光施設 SPring-8

問い合わせ番号

SOL-0000001112

ビームライン

BL04B1（高温高圧）

学術利用キーワード

A. 試料	無機材料
B. 試料詳細	結晶, 鉱物・岩石
C. 手法	Ｘ線回折
D. 手法の詳細	粉末結晶構造解析
E. 付加的測定条件	高圧（大型プレス）, 応力付加、変形, 高温（>>500度）
F. エネルギー領域	Ｘ線（>40 keV）
G. 目的・欲しい情報	結晶構造, 構造変化, 相転移

産業利用キーワード

階層1	工業材料, その他
階層2
階層3
階層4	格子定数, 結晶構造
階層5	回折

分類

A60.20 環境物質, A80.30 無機材料, M10.20 粉末結晶回折

利用事例本文

Energy-dispersive X-ray diffraction using a large-volume press, SPEED-1500 is a powerful tool for the direct research on the structure and properties of materials in the Earths interior under high-pressure and high-temperature condition. Figure shows the spinel-postspinel phase boundary in Mg₂SiO₄ olivine determined in this study. The present results suggest that the spinel to postspinel transformation should occur at a depth of about 600 km in the Earth, and this is inconsistent with the seismological observations, which show that the seismic discontinuities are located at the depth of 660 km. The reason of the inconsistency is controversial.

Fig. Phase boundary between the spinel and postspinel phases in Mg₂SiO₄ olivine.

[ Journal of the Japanese Society for Synchrotron Radiation Research 12, 17-18 (1999), Fig. 6,
©1999 The Japanese Society for Synchrotron Radiation Research ]

画像ファイルの出典

所内報

誌名

Research Frontiers (1997-1998)

ページ

15

測定手法

An energy-dispersive X-ray diffraction system attached to the Kawai-type large-volume press is shown in figure. A white X-ray beam from the bending magnet light source is collimated with vertical and horizontal slits to form a thin beam possessing a cross section of typically 0.05 x 0.1 mm². In order to carry out the energy-dispersive X-ray diffraction on the Kawai-type system, the first-stage anvils are cut holes to pass the X-ray beam. The incident white X-ray beam from the first-stage passes through the gaps between the second-stage anvils in a horizontal plane. X-rays diffracted by samples under high-pressure and high-temperature is detected by a pure Ge solid state detector (Ge-SSD) with a 4096 multi-channel analyzer. Diffraction data can be obtained with an energy range from 20 to 150 keV. Use of a collimator (0.05 mm width) and a receiving slit at a fixed angle to the direct beam permits only the diffracted X-rays from the sample to be detected. The horizontal goniometer covers a range of 2θ angles from -10 to 23° with an accuracy of 0.0001°. The X-ray acquisition time to obtain a diffraction profile is typically one to several minutes.

Fig. Schematic drawing of the energy-dispersive X-ray diffraction on the Kawai-type large-volume press.

画像ファイルの出典

BL評価レポート

ページ

14

測定準備に必要なおおよその時間

1 日

測定装置

装置名	目的	性能
SPEED-1500	High pressure and high temperature experiment	2500K, 30 GPa

参考文献

文献名
Scinece, 279, 1698(1998)

関連する手法

アンケート

SPring-8だからできた測定。他の施設では不可能もしくは難しい
本ビームラインの主力装置を使っている

測定の難易度

熟練が必要

データ解析の難易度

中程度

図に示した全てのデータを取るのにかかったシフト数

4～9シフト