Dielectric breakdown and partial discharge in BaTiO/sub 3/ ceramics

The possibility of a correlation between partial discharge characteristics, breakdown strength, and microstructure of the ferroelectric ceramics is investigated. Breakdown field and partial discharge inception field were measured for pure BaTiO/sub 3/ ceramics with different pore size distributions. The BaTiO/sub 3/ ceramics used in this study were sintered at either 1300 degrees C, 1350 degrees C, 1400 degrees C, or 1450 degrees C, which varied the pore size distribution only. The pore size of the barium titanate ceramics was found to increase with sintering temperature. The breakdown field and partial discharge inception field decreased with increase of sintering temperature, which is attributed to the large pore size in high-temperature-sintered specimens, the dielectric breakdown being caused by partial discharge within large pores.<
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