Difficulties in the application of laser welding technology in red copper welding
Release time：2022.02.11
Views：2796At present, the consumption of non-ferrous metals in industrial manufacturing, red copper ranks second only to aluminum. Red copper is widely used in construction industry, electrical, machinery manufacturing and other industries.
Laser welding has the advantages of high energy density, less molten metal, narrow heat affected zone, high welding quality and high production efficiency. However, due to the low absorption rate of high anti material to fiber laser, it is also difficult to process, which also has more requirements for laser light source.
Common problems in red copper welding:
(1) Difficult fusion and variability: due to the large thermal conductivity of red copper, the heat transfer speed during welding is very fast, and the overall heat affected zone of the welding area is also large, so it is difficult to fuse the materials together; Because the linear expansion coefficient of red copper is very large, when welding is heated, improper clamping force of fixture will deform the material.
(2) Prone to porosity: another big problem in red copper welding is porosity, especially in deep penetration welding. The generation of pores is mainly caused by two conditions: one is the diffusive pores directly generated by the dissolution of H2 in red copper, and the other is the reactive pores caused by redox reaction.
Methods of solution:
At room temperature, the absorptivity of red copper to infrared laser is about 5%, and when heated near the melting point, the absorptivity can reach about 20%. In order to realize the laser deep penetration welding of red copper, it is necessary to improve the laser power density.
Using high-power laser combined with swinging welding joint, stir the molten pool with light beam and expand the keyhole during deep penetration welding, which is conducive to gas overflow, making the welding process more stable, less spatter and less micro pores after welding.
Laser welding has the advantages of high energy density, less molten metal, narrow heat affected zone, high welding quality and high production efficiency. However, due to the low absorption rate of high anti material to fiber laser, it is also difficult to process, which also has more requirements for laser light source.
Common problems in red copper welding:
(1) Difficult fusion and variability: due to the large thermal conductivity of red copper, the heat transfer speed during welding is very fast, and the overall heat affected zone of the welding area is also large, so it is difficult to fuse the materials together; Because the linear expansion coefficient of red copper is very large, when welding is heated, improper clamping force of fixture will deform the material.
(2) Prone to porosity: another big problem in red copper welding is porosity, especially in deep penetration welding. The generation of pores is mainly caused by two conditions: one is the diffusive pores directly generated by the dissolution of H2 in red copper, and the other is the reactive pores caused by redox reaction.
Methods of solution:
At room temperature, the absorptivity of red copper to infrared laser is about 5%, and when heated near the melting point, the absorptivity can reach about 20%. In order to realize the laser deep penetration welding of red copper, it is necessary to improve the laser power density.
Using high-power laser combined with swinging welding joint, stir the molten pool with light beam and expand the keyhole during deep penetration welding, which is conducive to gas overflow, making the welding process more stable, less spatter and less micro pores after welding.
