ZnO-Bi2O3-Sb2O3-BaO系陶瓷的晶界相与抗退降性能

在通常的ＺｎＯ－Ｂｉ₂Ｏ₃－Ｓｂ₂Ｏ₃系电压敏陶瓷中，加入能构成压敏特性的钡添加剂，发现除已知的Ｂｉ₂Ｏ₃和Ｚｎ_2．３３Ｓｂ_０．６７Ｏ₄晶界相以外，还出现新的晶界相，分析表明是固溶有微量其它成分的偏锑酸钡（ＢａＳｂ₂Ｏ₆）晶相。同时还发现，ＢａＳｂ_{2关键词：}

GRAIN BOUNDARY PHASES AND ANTI-DEGRADATION PROPERTIES OF ZnO-Bi2O3-Sb2O3-BaO CERAMICS

Barium additive, which can resutt in a varistor character. was doped in the usual ZnO-Bi₂O₃-Sb₂O₃ varistor ceramics. It was found that a new grain boundary phase which is barium meta antimonate (BaSbA) crystal phase dissolving other trace compositions was formed besides the known Bi₂O₃ and Ｚｎ_2．３３Ｓｂ_０．６７Ｏ₄ grain boundary phases. It was also found that the ＢａＳｂ₂Ｏ₆ phase is thermally stable and it plays an important role in improving the degradation properties of the varistor ceramics. The anti-degradation abilities of the varistor ceramics under the long duration load voltage and the surge current are both enhanced obviously when the amount of the Bi₂O₃, Ｚｎ_2．３３Ｓｂ_０．６７Ｏ₄ and ＢａＳｂ₂Ｏ₆ grain boundary phases are in an appropriate ratio by controlling the amount of various additives. It is particularly valuable that the degradation properties of the V-I characteristics in backward direction are improved significantly.