Laser welding process
It is particularly valued and widely used in the automotive industry, where automotive panels are one of the five major categories of laser welding.
Used in automobiles, it can reduce the weight of the car body, improve the assembly accuracy of the car body, increase the stiffness of the car body, and reduce the stamping and assembly costs in the manufacturing process of the car body.
Xinfa welding equipment has the characteristics of high quality and low price. For details, please visit: Welding & Cutting Manufacturers - China Welding & Cutting Factory & Suppliers (xinfatools.com)
Laser self-fusion stack welding process for automobile panel parts
When the laser beam with a power density reaching a certain range (106~107 W/cm2) irradiates the surface of the material, the material absorbs light energy and converts it into heat energy. The material is heated, melted, and vaporized, producing a large amount of metal vapor, which escapes from the surface. Under the reaction force generated by the laser, the molten metal liquid is pushed around to form pits. As the laser continues to be irradiated, the pits penetrate deeper. When the laser stops irradiating, the molten liquid around the pits flows back and cools and solidifies. Weld the two workpieces together.
Factors affecting laser welding
1. Laser power
There is a laser energy density threshold in laser welding. Below this value, only surface melting of the workpiece occurs, and the penetration depth is very shallow, that is, the welding is performed in a stable heat conduction type; once this value is reached or exceeded, plasma will be generated, which is a sign of With the progress of stable deep penetration welding, the penetration depth will be greatly increased. If the laser power is lower than this threshold and the laser power density is small, insufficient penetration will occur and even the welding process will be unstable.
2. Welding speed
The welding speed has a great influence on the penetration depth. Increasing the speed will make the penetration shallower, but if the speed is too low, it will cause excessive melting of the material and welding of the workpiece. Therefore, there is a suitable welding speed range for a specific material with a certain laser power and a certain thickness, and the maximum penetration can be obtained at the corresponding speed value.
3. Defocus amount
To maintain sufficient power density, focus position is critical. On each plane away from the laser focus, the power density distribution is relatively uniform. There are two defocus modes: positive defocus and negative defocus. When the focal plane is above the workpiece, it is positive defocus, and when it is above the workpiece, it is negative defocus. Changes in defocus directly affect the width and depth of the weld.
4. Protective gas
During the laser welding process, inert gases are often used to protect the molten pool, but in most applications, gases such as argon, nitrogen, and helium are often used for protection to protect the workpiece from oxidation during the welding process and to blow away the plasma.
Post time: Feb-22-2024
