Elastic Constants of YCa_40(BO_3)_3 and NdCa_40(BO_3)_3 Single Crystals by the Pulse-echo Ultrasonic Method

摘要

Using the pulse-echo ultrasonic method, the velocities of the longitudinal and the shear bulk acoustic waves propagating in four crystallographic directions of YCa_(4O)(BO_3)_3 and NdCa_40(BO_3)_3 monoclinic single crystals were measured at room temperature and nine elastic constants were obtained. Some elastic constants important for possible acoustic applications have been investigated also at temperatures up to 900°C.