Accurate Measurement of the Temperature Coefficient of the Ultrasonic Velocity of Fused Quartz Near Room Temperature

摘要

A technique has been adapted to measure the relative change in the acoustic velocity of materials at frequencies up to 500 MHz with a maximum sensitivity of one part in 10 million. This technique is applied to the measurement of the temperature coefficient of the longitudinal-acoustic velocity of fused quartz over the temperature range 28-47 C. The longitudinal velocity is observed to increase linearly over this temperature range. The temperature coefficient of the fractional longitudinal velocity increase of fused quartz is determined to be (1.075 + or - 0.025) x .0001/deg C. This number is in agreement with the results of previous investigators and is the most accurate measurement available at room temperature. Keywords: Ultrasonic frequencies; Longitudinal acoustic velocity; Acoustic measurement. Reprints. (edc)