We developed a new diamond-SiC composite anvil for large volume press, which has superior hardness compare to a conventional tungsten carbide (WC) anvil. The diamond-SiC composite anvil is produced by the reaction of diamond and silicon powders using a hot isostatic pressing (HIP)¹, and pressure in excess of 30 GPa has been achieved using eight cubic anvils with 10 mm edge length in a Kawai-type multi-anvil (KMA) press². In addition, since the diamond-SiC composite anvil can transmit the X-ray/neutron beam, the measurable detection range in high pressure X-ray/neutron radiography and diffraction measurement can be expanded.

 Also in order to expand the experimental temperature range, we developed titanium compound materials, Ti₃SiC₂ and TiC+Al₂O₃. The use of the titanium compound heater in a high pressure cell has succeeded in generating very high temperatures over 2273K. Combining the diamond-SiC composite anvil and the titanium compound heater, the measurable pressure and temperature range using the X-ray/neutron beam can be expanded.

 Here, we present the development of high pressure and high temperature generation techniques and application of the viscosity measurement using synchrotron X-ray radiography. As a result of measuring the viscosity using the falling-sphere method, we successfully obtained the viscosity of liquid iron alloy up to 14 GPa.

References

[1] M. Shimono and S. Kume, J. Am. Ceram. Soc., 87, 752 (2004).

[2] O. Ohtaka, M. Shimono, N. Ohnishi, H. Fukui, H. Takebe, H. Arima, T. Yamanaka, T. Kikegawa, S. Kume, Phys. Earth Planet. Inter., 143-144, 587 (2004).