Abstract
The compressional and shear wave velocities in a multicomponent alloy, Wood's metal, were accurately determined by the pulse transmission method at temperatures between room temperature and 100°C. The melting point of Wood's metal was found to be 71.4°C, and the rates of temperature change upon heating and cooling were 1.887–0.063°C/min and 0.830–0.049°C/min, respectively. A large hysteresis loop in the relation between the sound velocity and temperature were observed around the melting point. The hysteresis depended strongly on the degree of supercooling, which was in turn affected by the rate of temperature change. The significance of the hysteresis loop in the melting-solidifying process is discussed by combining the present ultrasonic data with observations of the metal texture by metal-reflecting microscope.