HIGH-VOLTAGE OXIDE-ZINC VARISTOR CERAMIC Russian patent published in 2020 - IPC C04B35/453 H01C7/12 

FIELD: manufacturing technology.

SUBSTANCE: invention relates to methods of producing varistor ceramics and can be used in power engineering when producing high-voltage varistors, which are the main element of nonlinear overvoltage limiters. High-voltage oxide-zinc varistor ceramics contains oxides of zinc, bismuth, antimony, aluminum, cobalt and nickel in following quantitative ratio, wt. %: ZnO 77.5–82.5; Bi₂O₃ 4.66–6.56; Sb₂O₃ 2.05–2.95; Al₂O₃ 4.08–5.83; Co₂O₃ 3.32–4.37; NiO 1.92–3.48. Antimony and nickel oxides are related as 0.66–1.51. Technical result of invention is reduction of varistor ceramics leakage current density at provision of high breakdown voltage and non-linearity factor.

EFFECT: obtained varistor ceramics has breakdown voltage 3,7–5,1 kV/mm, nonlinearity coefficient 56–74, leakage current density 0,1–0,2 mcA/cm² and less.

1 cl, 9 ex, 1 tbl