Abstract
Pressure and temperature calibration of FB-belt type apparatus was carried out at pressures between 4 and 6GPa and temperatures between 1000 and 1500°C using pressure and temperature condition of diamond formation and CaGeO3 phase transition. Pressure and temperature points used as standard were minimum condition of diamond formation in the Ni-C system at 5.4GPa and 1384°C and in the Fe66-Ni34-C system at 4.98GPa and 1216°C. The temperature dependence of garnet-perovskite phase transition curve of CaGeO3, P (GPa)=6.9-0.0008T(°C), determined by Susaki et al. was also used as standard of the calibration. With increasing temperature the cell pressure increases about 20% between 1000 and 1500°C due to thermal expansion of NaCl used as pressure transmitting medium and the reaction cell. The amounts of pressure increase estimated both from the diamond formation and from CaGeO3 phase transition agreed within 0.05GPa.
