Pressure generation to 125 GPa using a 6-8-2 type multianvil apparatus with nano-polycrystalline diamond anvils

Abstract

Pressures to about 125 GPa at room temperature have been confirmed by synchrotron in situ X-ray observations, using a newly designed triple-stage (6-8-2) multianvil apparatus with nano-polycrystalline diamond (NPD) as the third-stage opposed anvils. Upon heating the sample at a fixed press load (500 tons), the pressure stayed virtually the same at temperatures to 1100 K, while it decreased to 83.7 GPa when the temperature was further increased to 1300 K. This pressure was maintained for 2 hours without notable decrease during the heating. The present 6-8-2 system can be used in studies of in situ X-ray observation of phase transitions under these pressures, which are far higher than those achieved in conventional Kawai-type multianvil 6-8 system. © 2010 IOP Publishing Ltd.