Measurement of Ultrasonic Wave Velocities and Elastic Moduli for Small Solid Specimens at High Temperatures

Abstract

An improved buffer rod-specimen unit is described for measuring longitudinal wave velocities in solids at temperatures up to 350°C. The method is particularly useful in determining elastic moduli of single crystals since very small path lengths in any prescribed direction can be employed. The use of molten metals to provide coupling at still higher temperatures is discussed. Several high-temperature techniques involving mode conversion at an impedance discontinuity for generating shear waves will be detailed, with particular interest in application to crystalline media. The various methods are illustrated with data for fused silica and single crystal germanium.