Laser welding is an important aspect of laser material processing technology. It can be categorized based on its working method into laser spot welders (manual welders), automatic laser welders, laser beam welders, and fiber-optic transmission laser welders. The process involves using high-energy laser pulses to locally heat small areas of the material, with the energy of the laser radiation diffusing into the material through thermal conduction, causing it to melt and form a specific molten pool, thereby achieving the welding objective.
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 relevant laser parameters. Laser deep penetration requires a continuous laser beam to perform the task, thus achieving material interconnection and welding depth. With technological upgrades (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 point, resulting in complete melting and penetration of the metal.
Compared to other traditional welding techniques, the main advantages of laser welding are:
1. The laser beam has a small focal spot with high power density, capable of welding high melting point and high-strength alloy materials.
2. Laser welding is a contactless processing method, free from tool wear and tool change issues. The laser beam energy and movement speed are adjustable, enabling various types of welding processes.
3. Laser welding offers high automation, controllable by computer, with rapid welding speed and high efficiency, allowing for convenient welding of any complex shapes.
4. Laser welding results in a small heat-affected zone and minimal material deformation, eliminating the need for further processing.
5. Lasers can weld workpieces inside vacuum chambers and within the interiors of complex structures.
6. Laser beams are easy to guide and focus, enabling transformations in all directions.
7. Laser welding is more convenient to operate than electron beam processing, as it does not require a strict vacuum equipment system.
8. Laser welding offers high production efficiency, stable and reliable processing quality, and good economic and social benefits.
Application:
The laser welding process is suitable for welding metals such as gold, silver, titanium, nickel, tin, copper, aluminum, stainless steel, galvanized steel, and their alloys. It can achieve precise welding between the same type of metal and different types of metals, and is widely used in industries such as aerospace equipment, shipbuilding, instruments and meters, electromechanical products, hardware accessories, kitchenware, digital accessories, fitness equipment, precision machinery, and automotive manufacturing.
