| As a kind of material of ramp-wave generator, Li2O-Al2O3-SiO2 system glass-ceramic has very important application in quasi-isentropic compression due to a low coefficient of thermal expansion and fine processing.In the thesis, by using the melting method followed by nucleation and crystallization, a kind of Li2O-Al2O3-SiO2 system glass-ceramic, which had a low coefficient of thermal expansion was successfully prepared. The effects of heat treatment (nucleation temperature, nucleation time, crystallization temperature, crystallization time) on the transparence, phase, microstructure, density and coefficient of thermal expansion of the prepared glass-ceramic were mainly investigated. The optimum conditions for the heat treatment were found out as follows: nucleated at 510-570℃ for 1-2 hours and successively crystallized at 800-880 ℃ for 1-2 hours. The results show that crystallization temperature is the important factor for the transparence of glass-ceramic. The crystallization temperature for transparent glass-ceramic whose main phase is P-quartz, should be less than 950℃ generally. When the crystallization temperature exceeds 950℃, the main phase of P-spodumene with a greater grain size is produced. As a result, opaque glass-ceramic is obtained. Under the optimum heat treatment schedule (nucleation temperature 550℃, nucleation time 2 hours, crystallization temperature 880℃, crystallization time 1hour), a kind of Li2O-Al2O3-SiO2 system glass-ceramic with the main phase of P-quartz, homogenous grains and a transparent appearance, whose coefficient of thermal expansion was 2.262×10-7/℃ (0900℃) and density was 2.5g/cm3, was successfully prepared. On the basis of the above results, the effects of the processing parameters on the coefficient of thermal expansion and density were further discussed. The result shows that the coefficient of thermal expansion of the samples rises at first, and then decreases with the increasing of nucleation temperature, nucleation time, crystallization temperature or crystallization time, while the density of samples changes on the contrary. It is found that, the law is induced mainly from regularly change of the content of p-quartz( low coefficient of thermal expansion, high density) resulting from transformation of condensate depression and crystal phase(β-quartz→β-spodumene).On one-stage light-gas gun, the experiment for quasi-isentropic compression bythe ramp-wave generator (Li2O-Al2O3-SiO2 system glass-ceramic) was explored. By impacting the ramp-wave generator, quasi-isentropic compression waves with an extended wave's front (0.3μs) were produced. Furthermore, the more the thickness of the ramp-wave generator, the long the front of the generated wave. Finally, on one-stage light-gas gun the quasi-isentropic compression to LY12-A1 samples was successfully realized by using the ramp-wave generator. The results of the present study offered a rather fine material and a feasible loading means for the quasi-isentropic compression.
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