ABSTRACT

Two ultrasonic measurement methods for pressure calibration to 4.4 GPa in a multi-anvil apparatus by measuring the travel times of longitudinal wave as a function of pressure are reported. The first method is to continuously calibrate pressure by combining the measured travel times of Z-cut quartz under hydrostatic pressure with the related equation of state and unit-cell parameters of quartz. The second method is fixed-point calibration, which is to calibrate the pressure by measuring the abrupt change of the longitudinal wave travel times since the samples, H₂O, Hg and Bi used in this study will undergo pressure-induced phase transitions at room temperature. Experimental results of these two methods are in good agreement. The quartz pressure scale obtained from this study is expressed as P(GPa) = 28.7(1−t_p/t_p0). The two ultrasonic measurement methods might be complementary means for pressure calibration in situations where other probe method is not conveniently available.

抽象的

报道了两种超声测量方法，用于通过测量纵波的传播时间随压力的变化，在多砧装置中将压力校准至4.4 GPa。第一种方法是通过将在静水压力下测量的Z切石英的行进时间与石英的相关状态方程和晶胞参数相结合，来连续校准压力。第二种方法是定点校准，这是通过测量纵波传播时间的突然变化来校准压力，因为本研究中使用的样品H ₂ O，Hg和Bi将在室温下经历压力引起的相变。温度。这两种方法的实验结果吻合良好。从这项研究中获得的石英压力标度表示为P（GPa）＝ 28.7（1- t _p / t _p0）。在其他探头方法无法方便使用的情况下，这两种超声测量方法可能是压力校准的补充手段。