Laser welding is a significant aspect of laser material processing technology. It can be categorized 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 heat a small, localized area of the material, with the laser's radiant energy diffusing into the material through heat conduction, causing it to melt and form a specific molten pool, thereby achieving the welding objective.
The principle of a laser welding machine is essentially to complete welding through pulse laser beams. It can be divided into heat conduction and laser deep penetration. The heat conduction principle refers to the area to be welded being heated by radiation. As surface heat gradually penetrates into the material interior through conduction, the workpiece can be melted with relative energy, repetition frequency, and relevant laser parameters. For laser deep penetration, a continuous laser beam is required to perform the work, thus achieving interconnection and welding depth of the material. With technological upgrades (categorized into pulse laser welding and continuous laser welding), pulse laser welding has no more than 100 spots per second, whereas continuous laser welding can reach up 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, causing the metal to fully melt and penetrate.
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, enabling welding of 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 energy and movement speed are adjustable, enabling various types of welding processes.
3. Laser welding boasts high automation, can be controlled by computers, offers rapid welding speeds, and high efficiency, allowing for easy welding of any complex shapes.
4. Laser welding results in minimal 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 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:
Laser welding technology is suitable for welding metals such as gold, silver, titanium, nickel, tin, copper, aluminum, stainless steel, galvanized steel, and their alloys, enabling precise welding between the same type of metal and different types of metal. It 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.
