نوع مقاله : مقاله پژوهشی
نویسندگان
1 ، پژوهشکده مواد پیشرفته و انرژی‌های نو، سازمان پژوهش‌های علمی و صنعتی ایران
2 گروه مواد در انرژی- پژوهشکده مواد پیشرفته و انرژی های نو- سازمان پژوهش های علمی و صنعتی ایران- تهران
3 پژوهشکده مواد پیشرفته و انرژی های نو، سازمان پژوهش‌های علمی و صنعتی ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
In this research, the ZnO-Bi2O3-Sb2O3- based varistor ceramic was made under an electric field of 300V/cm and a current density of 100 mA/mm2 by flash sintering method, and its properties were compared with the conventionally sintered sample. The density of the flash sinter sample reached 95.6% of the theoretical density and the microstructure and phases in it were similar to the conventional sinter sample. E-J curve showed that the sintered flash sample also has nonlinear behavior and varistor properties. The value of nonlinear coefficient was obtained for flash and conventionally sintered samples, 34.4 and 41.5, respectively. Using the thermionic emission model, the potential barrier height, the width of the depletion layer, the density of donors and the surface states at the interface of grain and grain boundary were measured under DC electric field. The electrical resistance value of the grain boundary, which was measured by the electrochemical impedance method, was lower in the flash sintered sample than in the conventional sintered sample, which is due to the lack of sufficient time for ions to diffuse completely from the volume of the insulating phase to the grain boundary. The stability of the samples was investigated by measuring the current creep by applying temperature and electric field. The results showed that the current leakage in the flash sintered sample is more than the conventional sintered sample.
کلیدواژه‌ها [English]
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