Laser welding is a significant aspect of laser material processing technology. It can be categorized based on its working method into laser seam welders (manual welders), automatic laser welders, laser spot welders, and fiber-optic transmission laser welders. Laser welding involves using high-energy laser pulses to locally heat small areas of the material, with the energy of the laser radiation being transferred and diffused into the material through thermal conduction, causing the material to melt and form a specific molten pool, thereby achieving the welding goal.
The principle of laser welding machines is essentially to complete welding through pulse laser beams. Its principle can be divided into thermal conduction and laser deep penetration. The thermal conduction principle refers to the pointer heating the area to be welded through radiation. As the surface heat gradually penetrates into the material interior through thermal conduction, the workpiece can be melted by relative energy, repetition frequency, and related laser parameters. For laser deep penetration, a continuous laser beam is required to perform the work, thereby achieving material interconnection and welding depth. With technological advancement (categorized as pulse laser welding and continuous laser welding), pulse laser welding has no more than 100 spots per second, while continuous laser welding can reach up to no more than 5,000 spots per second. This welding principle, under sufficient high-density laser irradiation, allows the welding material to rapidly absorb the energy of the laser beam at a specific point, resulting in complete melting and penetration of the metal material.
Compared to other traditional welding techniques, the main advantages of laser welding are:
1. The laser beam's focal spot is small, with high power density, capable of welding high melting point and high-strength alloy materials.
2. Laser welding is a non-contact process, eliminating tool wear and tool change issues. The laser energy and speed are adjustable, allowing for a variety of welding processes.
3. Laser welding offers high automation, controllable by computer, with fast welding speed and high efficiency. It facilitates welding of any complex shapes.
4. Laser welding results in a small heat-affected zone and minimal material deformation, eliminating the need for subsequent processing.
5. Lasers can weld workpieces inside vacuum chambers and within the intricate interiors of complex structures.
6. Laser beams are easy to guide and focus, enabling transformations in all directions.
7. Laser welding is more convenient than electron beam processing, as it does not require strict vacuum equipment systems.
8. Laser welding offers high production efficiency, stable and reliable processing quality, and good economic and social benefits.
Application:
Laser welding technology is suitable for welding metals such as gold, silver, titanium, nickel, tin, copper, aluminum, stainless steel, galvanized steel, and their alloys. It enables precise welding between the same type of metal and different types of metals, and has been widely applied in industries such as aerospace equipment, shipbuilding, instruments and meters, electromechanical products, hardware accessories, kitchenware, digital accessories, fitness equipment, precision machinery, and automotive manufacturing.
