A silver-copper melt with a sandwich structure

Abstract

The invention relates to silver-copper melt with a sandwich structure. The silver-copper melt comprises a copper core and silver layers arranged on two sides of the copper core, the silver-copper meltis in a strip shape, the width of the silver-copper melt is larger than or equal to 20 mm, and the thickness of the silver-copper melt is less than or equal to 0.2 mm. The preparation method comprises the following steps: weighing pure silver and oxygen-free copper, putting the pure silver and the oxygen-free copper into a vacuum sintering furnace for vacuum smelting, and then, pouring to preparea round silver ingot and a round copper ingot; performing finish machining on the round silver ingot into a hollow silver circular ring, and carrying out heat treatment; processing the round copper ingot into a copper rod, and then, assembling the copper rod and the hollow silver circular ring in a hot-fitting mode so that the copper rod and the hollow silver circular ring are in interference fit; a molding blank is assembled and put into the vacuum sintering furnace for diffusion reaction; a blank ingot formed by reaction diffusion is put into a horizontal extruding machine and extruded intoa strip material blank at a constant speed; the strip material blank is rolled in multi-pass and small variable ratio and cut by using a constant-tension rolling mill so as to obtain the strip-shapedsilver-copper melt. The prepared silver-copper melt in the invention has the advantages of excellent electric conduction and heat conduction performance, oxidation resistance, and low melting point and is easy to process.

Description

technical field [0001] The invention relates to the field of electrical engineering, in particular to a silver-copper melt with a sandwich structure. Background technique [0002] The fuse is a kind of current protector made according to the principle of breaking the circuit by melting the melt with the heat generated by itself after the current exceeds the specified value for a certain period of time. Fuses are widely used in low-voltage power distribution systems, control systems, and electrical equipment. As short-circuit and over-current protection, fuses are one of the most commonly used protection devices. The fuse is mainly composed of two parts, the melt and the fuse tube, as well as additional fillers. When in use, connect the fuse in series in the protected circuit. When the current of the protected circuit exceeds the specified value, and after a certain period of time, the heat generated by the melt itself will fuse the fuse, disconnect the circuit, and play a p...

AI Technical Summary

Problems solved by technology

[0003] Because pure silver has many excellent properties, it has always been the best choice for low-voltage fast fuses. However, on the one hand, the price of pure silver is high, which makes the cost of electrical products remain high. On the other hand, a large amount of precious metal silver is used to cause waste of resources. Therefore, the replacement of pure silver by cheap and expensive composite materials is a research hotspot in the field of melt materials at present. Among them, the silver / copper penetration composite material is a relatively mature product at present, but there are still many problems found in the use of this melt material.

At present, there are three main outstanding problems in the existing melt materials: (1) Although the silver / copper penetration melt material reduces the cost of raw materials, it greatly increases the cost of subsequent processing

In the design and manufacture of fast fuses, the melt generally uses the narrow neck size of the variable cross-section punching hole to determine the size of the fuse current. The dimensional accuracy of the punching hole is related to the accuracy of the fuse's fusing current. Since silver / copper penetrates the melt material The particularity of strip forming makes it require higher precision for punching processing equipment, which greatly increases the production cost of punching equipment feeding mechanism and punching mold; (2) At the same time, the melt material works in a conductive and atmospheric environment for a long time Under the environment, the copper part of the silver / copper penetration material is prone to oxidation, which will lead to the instability of the entire melt material and threaten the safety of the entire circuit; (3) pure silver melt materials and silver / copper penetration composite materials, narrow neck Mainly processed in the pure silver area, the melting point of pure silver is high, the temperature rise is large and the fuse is slow when the current is overloaded, and the circuit overload protection cannot be well realized; based on this, a kind of excellent electrical and thermal conductivity, anti-oxidation, low melting point and easy to be developed is developed. The processed silver-copper melt has become the primary problem of saving silver melt materials

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