Calculation Of Metallic Compression Isentropes And Study On Isentropic Compression Experiments By Detonation Driving

Nowdays, isentropic loading is one of the important tools to be used in research for materials EOS. The useful information of the caloric EOS can be obtained with isentrope data under a certain range of pressure and temperature. Isentropes can be used as the reference of Gruneisen EOS and other EOS forms, whose knowledge is very important for understanding the off-Hugoniot states.The equation of compression isentropes has been obtained in this thesis by employing the reference of Gruneisen EOS, general EOS form p = f(e,v), polynomial EOS and the SESAME database respectively. The compression isentropes of aluminum and copper have been calculated with the reference Hugoniot or EOS forms mentioned above. The compression isentropes of aluminum , copper, tungsten and tantalum within a range of ultrahigh pressure are also calculated with the SESAME database. The compression isentropes of aluminum calculated are compared with the ICE data of Shot Z864 at the Sandia Z machine and the data from reference[1].Some conclusions are obtained below: (1) in the low pressure (below 50GPa), the compression isentropes calculated with above methods coincide with each other. (2) in the intermediate pressure range (about 50GPa～ 200GPa), the compression isentropes calculated from the linear Hugoniot as the reference of Gruneisen EOS and the Appy EOS are much more approach to the experimental data or reference data. (3) in the high pressure range (about 200GPa～1TPa), the compression isentropes calculated from the quadratic Hugoniot curves as the reference of Grüneisen EOS is much more approach to the experimental data or reference data.(4) in the ultrahigh pressure range (above 1TPa), the compression isentropes calculated from the SESAME EOS database are much more approach to the experimental data or reference data. Above-mentioned conclusions can be referenced in the coming isentrope compression experiments.Finally, the detonation driven isentropic loading is numerical simulated, and the results are in good agreement with the experimental data. The results show that the quasi-isentropic compression experiments in the low pressure range can be come ture with explosive-loading device with an air cushion.The novelties of this thesis are: Firstly, the compression isentropes of metals in the ultrahigh pressure range have been calculated with the SESAME database. Secondly, the...