Laser welding is a significant aspect of laser material processing technology. It can be categorized into laser model welders (manual welders), automatic laser welders, laser spot welders, and fiber-optic transmission laser welders. Laser welding involves using high-energy laser pulses to heat small, localized areas of the material, with the energy of the laser radiation diffusing into the material through heat conduction, causing melting and forming a specific molten pool to achieve welding.
The principle of laser welding machines is essentially to complete welding through pulsed laser beams. Its principle can be divided into heat conduction and laser deep penetration. The heat 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 heat 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, thereby achieving material interconnection and welding depth. With technological advancement (categorized into pulsed laser welding and continuous laser welding), pulsed laser welding has less than or equal to 100 spots per second, while continuous laser welding can reach less than or equal to 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, enabling welding of high melting point and high-strength alloy materials.
2. Laser welding is a contactless processing method, eliminating tool wear and tool change issues. The laser beam energy and movement speed are adjustable, allowing for various 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 intricate interiors of complex structures.
6. Laser beams are easy to direct and focus, allowing for various directional transformations.
7. Laser welding is more convenient to operate compared to 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:
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 and different types of metals, and has been 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.
