Ultrasonic Measurement and Isothermal Equation of State for LY12Al under Static Pressures

The sound velocities of longitudinal wave and transverse wave for LY12Al were measured under static pressures using pulse echo overlap technique. According to the bulk modulus at zero pressure, KS0, and its pressure derivative KS0 yielded from the ultrasonic meansurements under very low pressures (0.5 GPa), three Isothermal Equations of StateMurnaghan EOS, Birch-Murnaghan EOS and Vinet EOS for LY12Al were reduced. It was found that the Vinet EOS deduced from ultrasonic data was adequate for describing the compressibility of aluminium and its alloy with fcc structure, even up to 200 GPa. Furthermore, the zero pressure Debye temperature and thermodynamic Grneisen parameter calculated from the ultrasonic data for LY12Al are 430.97 K and 2 025, respectively.