Measuring the isentropic compression curves and W-J parameters of tantalum and molybdenum via a pressure-jump method

An experimental method for determining the isentropic compression curve T(P) and the educed W-J parameter was tested. A series of rapid compression processes were conducted with tantalum and molybdenum up to 4.83 GPa and 12.8 GPa, respectively. Pressure jumps and induced temperature increase were recorded. Temperature change was corrected to exhibit an adiabatic condition. The T(P) curve was fitted with maximum levels of pressure and temperature, and the W-J parameter was determined by investigating its dependence on temperature and pressure. No additional parameter was introduced in this method. Results from the measurements of the T(P) curve and the W-J parameter are more accurate than the results obtained by using other calculation methods.