A method of manufacturing an ag-based electrical contact

Abstract

The invention discloses a method for manufacturing an Ag-based electrical contact. Using a laser selective melting method, firstly, a 4×105W / m2-10×105W / m2 laser is used to prefabricate a 20μm-50μm Ag2O transition layer on the surface of the contact bridge. Then, the three-dimensional structure of the Ag-based electrical contact is printed on the surface of the transition layer. The present invention utilizes means such as prefabricating the transition layer, introducing oxygen during the forming process, and reducing the laser energy density to reduce the reaction temperature of laser selective melting, avoid the loss caused by the evaporation of Ag with a low melting point, and make the Ag powder The loss of the machine is reduced by 20-30%, thus reducing the production cost.

Description

technical field [0001] The invention belongs to the technical field of advanced rapid manufacturing, and more specifically relates to a method for manufacturing an Ag-based electrical contact. Background technique [0002] The electrical contact is directly responsible for the task of connecting and disconnecting the circuit and load current. Its reliability directly affects the reliability of the electrical system as a whole, and is called the "heart" of the electrical appliance. The contacts are welded on the contact bridge, both of which directly affect the reliable operation and service life of the switching device. The contact bridge requires high electrical conductivity, weldability and certain strength, usually using copper alloy or iron-copper alloy. Contacts are required to have good electrical conductivity, thermal conductivity, low and stable contact resistance, and excellent corrosion resistance. At present, Ag-based contact materials, Cu-based contact materials...

AI Technical Summary

Problems solved by technology

The internal oxidation method has the characteristics of good material compactness, simple process, and high productivity, but it is difficult to fully oxidize the material, and the structure of the prepared contact parts is uneven, which seriously reduces its welding resistance and electrical life.

However, the powder metallurgy method has a long process flow, requires more forming equipment, and has higher manufacturing costs.

In the end, the contact material is welded on the contact bridge, and a transition layer with a certain thickness (200 μm to 800 μm) needs to be prefabricated between the two. The manufacturing process of the entire electrical contact part is long and the cost is high, so it is urgent to find a new manufacturing method To optimize the manufacturing process of such products, improve manufacturing efficiency and reduce manufacturing costs

[0004] Selective Laser Melting (SLM) is a powder bed melting process in Additive Manufacturing technology, which can be used to manufacture metal parts; however, the existing SLM uses a laser beam with extremely high energy density To melt the metal, the melting temperature field can reach 3000°C. If this method is introduced into the manufacture of Ag-based contact parts, it will cause serious evaporation loss of low-melting-point Ag during the forming process, which will affect the composition of the formed parts, and lead to Failure of Ag-based contact parts