Elastic Constants of Synthetic Sapphire at 27°C

The six elastic stiffness constants of synthetic sapphire were independently determined by pulse-echo and continuous-wave (cw) resonance measurements at a frequency of 15 Mc. The values obtained from the pulse-echo measurements are C11=4.902, C33=4.902, C44=1.454, C12=1.654, C13=1.130, C14=−0.232, in units of 1012 dyn/cm2. The results obtained from the cw resonance measurements are C11=4.920, C33=4.920, C44=1.468, C12=1.684, C13=1.164, C14=−0.234, in units of 1012 dyn/cm2. The results of the present investigation are compared with recent resonance measurements in the kc frequency range and with earlier work in the Mc range.