5:15 PM - 6:30 PM
[SIT06-P06] Technical development and improvement for sound velocity measurements of liquid Fe-S up to 15 GPa using ultrasonic pulse-echo method
Keywords:core, sound velocity, liquid Fe-S, high pressure
High-pressure and high-temperature experiments were conducted at the AR-NE7A beamline at the KEK PF-AR synchrotron facility. High pressure was generated by Kawai-type multi anvil apparatus (MAX-III). High temperature was generated using cylindrical resistive heater made of Al2O3 + TiC composite. The sample was enclosed in a flat-bottomed cylinder container made of BN with a buffer-rod and a backing plate made of sapphire single crystal. We determined the pressure and temperature simultaneously without a thermocouple from the unit-cell volumes of NaCl and MgO by employing their equations of state. Sound velocity was measured by ultrasonic pulse-echo overlap method. The sample melting was identified during the experiments using X-ray diffraction, and was confirmed afterwards from textural observations of the run products.
Preliminary results show the error in sound velocity of liquid Fe-S at 15 GPa is approximately 2.5% under good conditions. In our previous experiments, the error in sound velocity below 7 GPa was approximately 1% under the best conditions. Taking it into account, our newly techniques can provide satisfactory accuracy. Details and latest experimental results will be presented.