Welding process used for copper-aluminum composite busbars

Abstract

The invention provides a welding process used for copper-aluminum composite busbars. The welding process used for the copper-aluminum composite busbars comprises the following steps (1) weld surfacesof the copper-aluminum composite busbars needing to be connected in an overleaping mode are coated with a special soldering flux; (2) one of two weld surfaces of the copper-aluminum composite busbarsis coated with special soldering paste; and (3) after being connected in the overlapping mode, the lapped surfaces of the two copper-aluminum composite busbars are clamped through a clamping cylinderof a resistance welding machine, are pressed through a graphite electrode, are welded, and then are placed in water to be cooled, and welding is completed after the copper-aluminum composite busbars are air-dried. By adoption of the welding process, overlap welding of the copper-aluminum composite busbars is achieved, efficient and simple operation of the resistance welding process is reserved, the copper-aluminum composite materials are prevented against damage in the welding process, and the shear bonding strength of the weld surfaces is over 15MPa; and by adoption of the welding process, the welding quality can be easily ensured by adjusting the welding current, the welding time, the number of pulses and the like when the sizes of workpieces are changed, and the welding process can alsobe used for welding products in different shapes by changing the shape of the electrode.

Description

technical field [0001] The invention belongs to the field of welding technology, and in particular relates to a welding process for copper-aluminum composite bars. Background technique [0002] As the world pays more and more attention to energy conservation and environmental protection, the requirements are getting higher and higher, and the application of copper-aluminum composite row is expanding. Many customers put forward the requirement of lap welding for energy saving, emission reduction and cost reduction, that is, lap welding on the main row By superimposing local narrow rows, the ordinary copper-aluminum composite row with rectangular cross-section is transformed into a special-shaped row with increased local thickness, so as to solve the problem of insufficient current carrying with space constraints. Copper-aluminum composite bar adopts ordinary resistance welding process, which will inevitably lead to difficult welding, because resistance welding uses the contac...

AI Technical Summary

Problems solved by technology

Copper-aluminum composite bar adopts ordinary resistance welding process, which will inevitably lead to difficult welding, because resistance welding uses the contact resistance between conductors to heat up through a large current, so that the welding part of the workpiece melts instantly, then cools and solidifies, and then fuses and welds together

Due to the presence of aluminum in the middle of the copper-aluminum composite row, the copper-copper contact surface is large (to ensure the electrical conductivity, the contact surface must be large), and the electrical performance of the material itself leads to a small contact resistance, which is different from the resistance welding requirement. Contact resistance is large Therefore, if copper can be melted and welded, the resistance of aluminum will be greater, and it will already melt under the same current, which will destroy the performance of raw materials, so the ordinary resistance welding process cannot meet the requirements.

Images