Preparation of Bismuth Surfaces for Ultrasonic Attenuation Measurements.

A combined electropolishing-grinding technique is described, which produces plane, single, crystal surfaces on bismuth that yield significantly lower values for the acoustic attenuation above 30 Mc/sec than do standard techniques. The frequency dependence of the excess attenuation introduced by standard surface-grinding techniques has been measured and the results compared to various theories of attenuation in polycrystalline material. [ABSTRACT FROM AUTHOR]