Ultrasonic Velocities of Sound in Some Metallic Liquids. Adiabatic and Isothermal Compressibilities of Liquid Metals at Their Melting Points

The ultrasonic velocities of sound at 12 mc in 12 pure liquid metals at their melting points under atmospheric pressure and in 4 equi-atomic liquid metallic mixtures have been determined by the use of the electronic pulse-circuit technique. For the pure metals the adiabatic and isothermal compressibilities have been computed. The compressibilities were generally found to be somewhat larger than for the corresponding solids at room temperatures. A calculation of Grüneisen's γ for the liquid metals shows that this quantity, in the case of normal metals, does not change appreciably on going from the solid state at room temperature to the liquid at moderately elevated temperature. These facts support the familiar view that the liquid metals at temperatures not far above their melting points are in a ``solid like'' state, and that equations of state for the solid state may be applicable to such liquids.