Electrical contacts are core components in electrical switches, responsible for connecting and disconnecting circuits and carrying current. They are widely used in low-voltage and high-voltage electrical appliances such as air switches, relays, and AC/DC contactors, and are applied in various fields of modern society, including civilian, military, aerospace, and aviation. Below, we introduce a preparation method for an environmentally friendly silver-tungsten alloy electrical contact material.
This preparation method for silver tungsten alloy electrical contact material can solve the problems of cadmium pollution and overheating issues in existing silver cadmium oxide electrical contact materials. The preparation method includes the following steps:
(1) Melting pure silver ingots and then atomizing them to produce pure silver powder;
(2) Mixing the pure silver powder with tungsten powder to form a silver-tungsten mixed powder, wherein the pure silver powder content is 70wt% and the tungsten powder content is 30wt%;
(3) Further ball milling the silver-tungsten mixed powder for 20-28 hours;
(4) Pressing the pulverized silver-tungsten mixed powder into a blank using cold isostatic pressing;
(5) Sintering the blank into a silver-tungsten alloy ingot;
(6) Cutting the silver-tungsten alloy ingot into a predetermined electrical contact size.
Precautions for this preparation method:
1) The melting temperature in step (1) is 1150℃, and the refining time is 3 minutes; the pure silver powder is -150 mesh.
2) In step (3), the ball-to-material ratio is 5:1. 3) The sintering method in step (5) is repeated pressing and sintering; the pressure of each repeated pressing and sintering is 300 MPa, and the holding time is 3 minutes; the temperature of each vacuum sintering is 900℃, and the sintering time is 3 hours.
The silver-tungsten alloy electrical contact material prepared using this method can serve as a good substitute for silver cadmium oxide electrical contact materials. It has comprehensive advantages such as being non-toxic, having high thermal stability, and being resistant to welding, and is widely used in household appliances, lighting switches, protective switches, contactors, power relays, and other fields.
Post time: Mar-19-2026