Laser welding is one of the important aspects of the application of laser material processing technology. Its principle is to radiate high-intensity laser to the metal surface, and melt the metal to form welding through the interaction between laser and metal. Because laser welding has the unique advantages of high speed, large depth, small deformation, energy saving and environmental protection, it has been successfully applied to the precision welding of micro and small parts. The emergence of high-power CO2 and high-power YAG lasers has opened up a new field of laser welding, obtained deep penetration welding based on the theory of keyhole effect, and has been widely used in machinery, automobile, steel and other industrial sectors.
Laser welding equipment is simple and can be carried out at room temperature or under special conditions. For example, when the laser passes through the electromagnetic field, the beam will not shift; Laser can weld in vacuum, air and some gas environment, and can weld through glass or materials transparent to the beam.
After focusing, the laser beam can obtain a very small spot and can be accurately positioned. It can be applied to the assembly and welding of micro and small components produced in large quantities. For example, due to the use of laser welding, the production efficiency is greatly improved, the heat affected zone is small, and the solder joint is pollution-free, which greatly improves the quality of welding.
It can weld inaccessible parts, and implement non-contact long-distance welding, which has great flexibility. Especially in recent years, the use of optical fiber transmission technology has made laser welding technology more widely popularized and applied.
The laser beam is easy to realize the beam splitting according to time and space, and can carry out multi beam simultaneous processing and multi station processing, which provides conditions for more precise welding.
With the rapid development of industrial laser industry, the market has higher and higher requirements for laser processing technology. Laser technology has gradually changed from single application to diversified application. Laser processing is no longer a single cutting or welding. The market has more and more demand for the integration of cutting and welding. The cutting and welding integrated laser processing equipment of laser cutting and laser welding came into being.
In recent years, China has made great achievements in the development of high-power laser. The developed laser power has reached and exceeded 10000 watts. It has formed more than ten kinds of application processes such as laser welding, cutting, drilling, surface treatment, alloying, cladding, rapid prototyping manufacturing, direct molding, photolithography and so on. It is widely used in automobile, electronics, aerospace, machinery, metallurgy, railway, shipbuilding and other industrial fields.
As an advanced welding method with high quality, high precision and high speed, laser welding has attracted extensive attention The research and development of laser welding has set off a climax, and laser welding has become one of the most promising welding methods.
