Method and product thereof for preparing ag-based tungsten-containing electrical contact material based on foaming infiltration process

Abstract

The invention discloses a method for preparing an Ag-based tungsten-containing electrical contact material based on a foaming infiltration process and a product thereof, specifically a method for preparing an Ag (W, WC) electrical contact material with a high silver content and low resistivity by an infiltration process method. Add a foaming agent to the Ag-based mixed powder for sintering strengthening, and sinter the sintered-strengthened Ag-based powder to wrap the spacer above the liquid phase and then crush and sieve to obtain a high-strength porous Ag-based powder. The body is pressed into a skeleton, and then a pure silver sheet is placed on the skeleton, and the skeleton is infiltrated in liquid phase at a high temperature to obtain an Ag-based electrical contact material with high silver content and low resistivity. The invention solves the problem that Ag-based electrical contact materials with high silver content can only be produced by solid-phase sintering process, and has higher density and anti-burning loss compared with Ag-based electrical contact materials with the same silver content prepared by sintering process Capability, lower resistivity, electrical life and other performance have been greatly improved.

Description

technical field [0001] this invention The invention relates to the field of electrical contact materials, in particular to a method for preparing an Ag-based tungsten-containing electrical contact material based on a foaming infiltration process and a product thereof. Background technique [0002] Ag-based electrical contact materials, especially AgW and AgWC electrical contact materials are used in circuit breakers, miniature circuit breakers, and leakage protection switches. They are generally made by infiltration process, and the WC content is between 30wt% and 80wt% or W content is between 30wt% and 80wt%. between 40wt%-80wt%. In recent years, due to the consideration of energy consumption and safety, the requirements for switch temperature rise in switch design are getting higher and higher, especially in miniature circuit breakers, the contact resistance of materials with WC content higher than 30wt% or W content higher than 40wt% It is difficult to meet the requirem...

AI Technical Summary

Problems solved by technology

In this way, the manufactured product contains part of the infiltrated structure, and the main structure is still a solid phase sintered structure, and it is difficult to ensure the uniformity of the structure.

At the same time, due to the high ductility and toughness of silver and the high strength of WC (W), after AgWC (W) infiltrates and densifies, it is very difficult to break the material, and it is even more difficult to break into powder with an ideal particle size distribution. This process is difficult to achieve. mass production

[0010] The Chinese invention patent with the publication number CN104209520A adds a polyacrylate pore-forming agent to the powder to increase the pores. The powder produced by this method has low strength and can meet the production requirements when making Ag(W, WC) materials with low silver content. It is required that when making Ag-based electrical contact materials with a WC content of less than 30wt% or a W content of less than 40wt%, the skeleton will collapse or even burst due to the severe deformation of the pores during the infiltration process.

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