A new measurement of the basic elastic and dielectric constants of quartz

A project was undertaken to measure the elastic and associated parameters of quartz to very high accuracy using a fully automated measurement system. Measurements were made of the properties of standard-grade synthetic quartz and of very-high-purity quartz. Significant differences between the two grades of quartz were found that are fully consistent with an anelastic relaxation of the known point defects in impure quartz. An automated pulse-echo phase detection system was used to gather an extreme large amount of transit time data which was then corrected for different effects and used to determine the parameters of the transducer bond accurately. Interferometry was used to eliminate length measurement error, and thus a highly accurate velocity measurement could be made. The dielectric moduli were measured using a capacitance technique and literature values for the piezoelectric moduli were used. A computer optimization routine was developed to fit the best set of independent elastic moduli to the entire set of experiment data