COMPRESSION OF MERCURY TO HIGH PRESSURE.
YALE UNIV NEW HAVEN CONN KLINE GEOLOGY LAB
Pagination or Media Count:
A method for calculating volume results from high pressure acoustic data was developed which is not limited to small compressions by the assumption of a constant ratio of isothermal to adiabatic compressibility. This method thereby extends the useful range of the ultrasonic technique for determining compression data. In order to demonstrate the technique, high pressure sonic velocity experiments were performed as a function of temperature on liquid mercury. The apparatus and techniques necessary for determining the velocity of sound in the Hg and for generating and measuring high pressures were developed. A variant of the pulse-echo technique was used to determine the sonic velocity. A supported cylinder-and -piton pressure apparatus was constructed which is capable of attaining pressures of about 25kb. The Hg sample was held in a small stainless steel container which was inserted in the 1 in. bore of the pressure vessel. Pressure was determined by monitoring the resistance of a coil of Au - 2.1 Cr wire which was calibrated for pressure against a dead weight tester. The volume data obtained were analyzed to determine the functional form of the equation of state of liquid Hg. It is found that the equation of state is most appropriately written as an expansion of P either in terms of V sub zeroV or in terms of 1nV. Author
- Properties of Metals and Alloys