Large Capacity, High-Pressure Generating Equipment with Transformation Mechanisms (SPEED-Mk II)

◆Equipment overview

Large capacity samples（~mm³）can be pressurized and heated up to 100GPa. In addition to the main ram, a sub-ram is provided for transformation in the guide block, allowing transformation experiments under high pressure.

◆Features of the Equipment

This system can expose relatively large-sized samples（~mm³）to multi-axis compression in a quasi-hydrostatic environment. Also, since it can be heated stably with a resistance heater inside a high-pressure cell, it is suited for cases of high-pressure substances. With this equipment, samples in high-temperature, high-pressure states can be irradiated with white X-rays, to observe X-ray absorption images, perform energy distribution XRD measurements, and even angle distribution XRD measurements using high-energy monochromatic X-rays.

High-Pressure Press
This equipment is a 2-stage, Kawai-type high pressure generator that can apply loads up to 1,500 tons per sample. In addition to the main ram, there is a built-in transformation ram that is capable of applying a load of 300 tons, and after the main ram pressurizes to quasi-hydrostatic pressure, single axis compression transformation is possible by the transformation ram. Also, this equipment has a high precision distance between the anvil surfaces, and high pressures of up to 100GPa can be generated using a sintered diamond anvil. By incorporating a resistance heater inside the high-pressure cell, it is possible to heat to 3000℃.

X-ray Beam Monitor
X-ray absorption images are observed using an X-ray beam monitor manufactured by Hanamatsu Photonics. It is converted to visible light using a GAGG fluorescent plate, then imaged with a general-purpose optical camera lens. The camera used for scientific measurements is a sCMOS camera, also manufactured by Hanamatsu Photonics. The effective resolution is approximately 3μm/pix.

Ge-SSD
XRD measurement uses energy-dispersive X-ray diffraction. Measurements of the X-ray diffraction energy spectrum are completed using a permanently installed Ge-SSD manufactured by Mirion Technologies (Canberra), with a measurable energy range of 10～150keV.

Large Area 2-Dimensional Detector
For angular transformation X-ray diffraction measurements using high-energy, monochromatic X-rays (energy ～61keV), the Debye-Scherrer ring can be obtained using a large-area CCD detector manufactured by Rayonix. In particular, it is effective for strain and stress measurements applied to high-pressure transformation experiments.

◆Equipment accessories

For heating with the above high-pressure press, an AC power supply of (2kW) and a DC power supply of（1.5kW×3）is equipped, a large current（～300A）can be applied to a small heater to heat the sample to several thousand degrees.
In addition to these X-ray measurement instruments, there is an ultrasound echo measurement system used to measure the elastic wave velocity (modulus of elasticity) of the sample, as well as a four-terminal digital multimeter to measure electric resistance.

◆Experiment / sample preparation

For the first stage, a 50mm by 27mm carbide anvil is used, and for the second stage a 26mm by 14mm carbide anvil is used. In addition, a sintered diamond anvil can also be used, as well as a 6-6 guide frame for pressurization, making it easy to use standard pressure mediums for pressurizations. For angle dispersion X-ray diffraction experiments, a cone-shaped, first-stage anvil is used allowing for 2θ=10°diffraction data to be acquired. In order to obtain the entire rotation of the Debye-Scherrer ring, a cone-shaped anvil is used at the second-stage, also a c-BN anvil which has excellent X-ray transparency must be specially prepared.

◆Experimental procedure / precautions

For details on experimental procedures, please ask the person in charge of the BL.
General experimental procedure,
(1)High Pressure Cell, Sample Preparation
High-pressure cells are designed and created depending on the desired pressure, temperature, oxygen atmosphere, etc. The sample is prepared using powdered pellets or sintered bodies.
(2)Instrument Calibration
Ge-SSD energy calibrations and 2θ goniometer calibrations are performed.
(3)High-Pressure Cell Installation and Standard Pressure Measurements
The state of the sample before pressurization is confirmed by X-ray radiography, then XRD data can be acquired. The constant pressure data is significant for quantitative discussions of high-pressure data, and is essential for computing pressure.
(4)Increasing Pressure & Pressure Measurements
The high-pressure cell can be pressurized with the large press. It usually takes 3～5ton/min to slowly pressurize. During pressurization, the generated pressure is calculated from the shrinking of the crystal lattice structure, obtained by XRD measurements of the high-pressure cell inside the substance. The pressurization and pressure measurements are repeated until the target pressure is reached, which usually takes several hours.
(5)Heating & Data Measurements
After reaching the target pressure, heating is started with an internal heater. Since there is a heater transformation due to pressurization, it must be heated to the target temperature while the stability of the heater is carefully observed. The XRD data of the sample is acquired while the temperature rises, and phase changes as well as lattice changes are observed.
Repeat (4) ～ (5) when a large amount of data is acquired on the pressure – temperature plane.


Special care must be paid to the installation of high-pressure cells with chain blocks, as well as when operating large presses, as this may lead to serious accidents.
Also, white X-rays significantly damage whatever they irradiate. Please no not install cables, detectors, etx on the X-ray axis.

◆Contact

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◆List of representative treatises

Sharp 660-km discontinuity controlled by extremely narrow binary post-spinel transition
Takayuki Ishii, Rong Huang, Robert Myhill, Hongzhan Fei, Iuliia Koemets, Zhaodong Liu, Fumiya Maeda, Liang Yuan, Lin Wang, Dmitry Druzhbin, Takafumi Yamamoto, Shrikant Bhat, Robert Farla, Takaaki Kawazoe, Noriyoshi Tsujino, Eleonora Kulik, Yuji Higo, Yoshinori Tange & Tomoo Katsura
Nature Geoscience 23 Sep. 2019:
Vol. 12, pp. 869-872
DOI: 10.1038/s41561-019-0452-1

Intermediate-depth earthquakes linked to localized heating in dunite and harzburgite
Tomohiro Ohuchi, Xinglin Lei, Hiroaki Ohfuji, Yuji Higo, Yoshinori Tange, Takeshi Sakai, Kiyoshi Fujino & Tetsuo Irifune
Nature Geoscience 28 Aug. 2017:
Vol. 10, pp. 771-776
DOI: 10.1038/ngeo3011

Mantle dynamics inferred from the crystallographic preferred orientation of bridgmanite
Noriyoshi Tsujino, Yu Nishihara, Daisuke Yamazaki, Yusuke Seto, Yuji Higo & Eiichi Takahashi
Nature 17 Mar 2016:
Vol. 539, pp. 81-84
DOI: 10.1038/nature19777

Stability of hydrous silicate at high pressures and water transport to the deep lower mantle
M. Nishi, T. Irifune, J. Tsuchiya, Y. Tange, Y. Nishihara, K. Fujino & Y. Higo
Nature Geoscience 02 Feb. 2014:
Vol. 7, pp. 224-227
DOI: 10.1038/ngeo2074

P-V-T equation of state for ε-iron up to 80 GPa and 1900 K using the Kawai-type high pressure apparatus equipped with sintered diamond anvils
Daisuke Yamazaki, Eiji Ito, Takashi Yoshino, Akira Yoneda, Xinzhuan Guo, Baohua Zhang, Wei Sun, Akira Shimojuku, Noriyoshi Tsujino, Takehiro Kunimoto, Yuji Higo, Ken Ichi Funakoshi
Geophysical Research Letters 28 Oct. 2012
Vol. 39, no. 20. pp. 20308-
DOI: 10.1029/2012GL053540