Improved metal-glass electrical resistance material and resistance elements constructed therefrom

摘要

A metal-glass resistance material comprises 84 to 43% by weight of glass and 16 to 57% by weight of an alloy comprising gold, palladium and silver. The material may also include 3% by weight of a semi-conductor comprising 95% copper oxide and 5% tin oxide. Two resistances are described, one suitable for a rotary potentiometer, and the other for use as a linear potentiometer or as a fixed resistor. The base on which the resistance material is fired is a ceramic, e.g. steatite, fasterite, alumina, or a zircon porcelain. The resistance material is prepared from a mixture of finely powdered glass and resinates of the alloying metals and semi-conductor oxides, and the result is very fine particles of glass coated with extremely small particles of conductive material; this powder is mixed with a suitable liquid carrier for application to the base material and fired to give a continuous phase of solidified glass. The two glasses described have compositions: .% by weight..(1).(2) .Lead oxide ...72.15.65.68 .Zinc oxide ...5.40.5.41 .Boric oxide ...9.04.10.00 .Silica .. ...13.41.16.51 .Zirconium oxide.-.2.40