| 摘要 |
Metal-oxide varistor compositions having a characteristically low voltage drop and low leakage current contain a reaction product which is produced by sintering a mixture of zinc oxide, bismuth oxide and other metal oxides and by the addition of 0.5 to 500 ppm by weight of aluminium or 0.1 to 500 ppm by weight of gallium, or a maximum of 100 ppm by weight of a mixture of both. Metal-oxide varistors manufactured from this composition exhibit a ratio of the voltage for producing a current intensity of 2.7 x 10<2>A cm<-2> to the voltage which produces a current density of 1.33 x 10<-4>A cm<-2> of 1.9:1 or less. Overvoltage suppressors which are produced using this material require no series-connected spark gap, as is otherwise normal. |
