Effects of Thermal Annealing for Barium and Silicon-Added Bismuth Based Zinc Oxide Varistors on Electrical Properties and Grain Boundary Structure

Abstract:

In order to fabricate varistors with low varistor voltage, the effects of thermal annealing of CoMnBaSi-added Bi based ZnO varistors on electrical properties and the grain boundary structure were investigated. The varistor voltage for the BiCoMnBaSi-added ZnO varistor decreased in half by thermal annealing for a short time. The resistance to electrical degradation was most improved by the addition of SiO₂ and thermal annealing for 1020 min. It is suggested that the composition of Bi and Si in the sheet-like deposit is changed by varying the annealing time and the resistance to electrical degradation is improved by both addition of SiO₂ as well as thermal annealing for short time.

• Periodical: Key Engineering Materials (Volume 582)
• Pages: 218-221
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.582.218
• Online since: September 2013
• Authors: Atsuko Kubota, Yuuki Sato, Shinzo Yoshikado
• Keywords: Back Scattering Electron Mode, Bi-Based ZnO Varistor, Electrical Properties, Grain Boundary Structure, Low Varistor Voltage, Thermal Annealing

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