Bi2O3 modification for use in varistors

• Autorzy: Mielcarek W. , Prociów E. , Nowak-Woźny D.
• Konferencja: V Konferencja Naukowa Postępy w Elektrotechnologii, Jamrozowa Polana, 8-10 września 2003 r.
• Języki publikacji: EN

Abstrakty

EN

Varistor operating voltage is very close to working voltage of the protected device and are not allowed to change much with time. ZnO ceramics accesses varistor property during sintering, due to addition of small amount of Bi2O3 and other metal oxides by developing potential barriers at ZnO grain boundaries. The degradation occurs, among others because a decrease in barrier height is caused by migration of oxygen ions that exist in the intergranular layers. The initial varistor properties could be restored by annealing at about 400 grad C or by doping with PbO-B2O3 based glasses. An entirely new approaches how to prevent ZnO varistor from degradation consists in modifying Bi2O3 ionic conductivity by doping it with metal ions. Ionic conductivity of systems constituted with ZnO and metal ion doped Bi2O3 were measured. It was found out that doping Bi2O3 with metal ion is effective tool of hindering varistor degradation but varistor susceptibility for degradation is not strictly connected with the high ionic B12O3 conductivity.

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje
• Rocznik: 2003
• Tom: Vol. 38, nr 13
• Strony: 311--316
• Opis fizyczny: Bibliogr. 11 poz., rys., tab.

Twórcy

autor

Mielcarek W.

• Institute of Electrotechnics in Wrocław

autor

Prociów E.

• Institute of Electrotechnics in Wrocław

autor

Nowak-Woźny D.

• Technical University of Wrocław

Bibliografia

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