A method of determining acoustical physical constants for class 32 crystals by the LFB/PW ultrasonic material characterization system

摘要

We developed a new method of determining acoustical physical constants for Class 32 crystals using the line-focus-beam (LFB)(plane-wave (PW) ultrasonic material characterization system. Constants can be determined by measuring the velocities of longitudinal and shear waves and of leaky surface acoustic waves (LSAWs) propagating on the water-loaded surfaces for three principal X-, Y-, and Z-cut plate specimens, in addition to measurements of dielectric constants and density. Numerical simulations were carried out using synthetic α-quartz whose precise constants were already obtained, in order to choose proper modes and propagation directions for the accurate determination. This method was successfully demonstrated for natural α-quartz, having a good agreement within 0.39 m/s between measured and calculated LSAW velocities.