Method for manufacturing pure copper/copper chromium alloy composite contact material

Abstract

The invention provides a method for manufacturing pure copper / copper chromium alloy composite contact material, comprising the following steps of: first, carrying out surface pretreatment on pure copper substrate; second, mixing 60-85 percent of copper powder and 15-40 percent of chromium powder evenly according to weight percentage , mixing binder and Cu-Cr powder according to the volume ratio of 1: 1.6-2, adding acetone for dilution and stirring into paste, and coating a Cu-Cr layer with the thickness of 1.2-1.8mm on the surface of the pure copper and drying at 80-100 DEG C in an oven; third, carrying out laser cladding by adopting a 5kW multifunctional CO2 crossflow laser, wherein the process parameters are that the output power is 1.5-2.5kW, the scanning speed is 6-15mm / s, the light spot diameter is 3mm, and single track cladding and overlapping rate of multi-track cladding is 30-45 percent, and protecting a molten pool with argon gas; and fourth, carrying out leveling and polishing treatment on the surface. In the method, a Cu-Cr alloy layer with good wear resistance and electrical erosion resistance can be obtained on the surface of the pure copper, so that the core part can remain the excellent conductivity of the pure copper.

Description

Technical field: [0001] The invention belongs to the technical field of metal materials, and in particular relates to a method for manufacturing a pure copper / copper-chromium alloy composite contact material. Background technique: [0002] The contact is the key component of the vacuum circuit breaker. The ideal vacuum contact material should have the following properties: ① High current breaking capacity; ② High voltage withstand capacity; ③ High electrical conductivity and thermal conductivity; ④ Good anti-welding performance ; ⑤ low arc burn rate; ⑥ low contact wear; ⑦ low cut-off value; ⑧ good processing performance. Because these properties are contradictory, they are often affected by various factors in the actual application process, and cannot meet the above indicators at the same time. [0003] According to the performance requirements of vacuum contact materials, although pure copper has high electrical and thermal conductivity and good processing performance, it ...

AI Technical Summary

Problems solved by technology

Although the Cu-Cr series alloys prepared by these methods have been used as contact materials, they all have their own shortcomings and deficiencies.

Among them, the main disadvantage of powder metallurgy method is that the size and spacing between Cr particles are too large, the structure uniformity of the material is low, and the content of oxygen and nitrogen is too high, which reduces the breaking capacity of the contact current.

The disadvantage of the infiltration method is that the production efficiency is low, the chromium particles are relatively coarse, and the chromium content must reach a considerable proportion, which seriously reduces the conductivity

However, the production cost of the arc melting method is relatively high, and many process parameters need to be further explored and improved.