Due to the high power density and fast energy release of laser welding, the processing efficiency is higher than that of traditional methods. Laser welding processing has more superior processing characteristics than traditional processing. Laser welding uses high-energy laser pulses to locally heat the material in a small area. The energy of laser radiation is guided to the internal diffusion of the material through heat transfer, and the material is melted to form a specific molten pool. So what is the application scope of laser welding machine?
1. Manufacturing
Laser tailor welding technology has been widely used in foreign car manufacturing. According to statistics, in 2000, there were more than 100 laser tailor welding production lines for cutting blank plates worldwide, with an annual output of 70 million pieces of car component tailor welding blank plates, and continues to grow at a high rate. Some cutting blank structures are also adopted for domestic production and imported models. In Japan, CO2 laser welding is used to replace flash butt welding for the connection of rolled steel coils in the steel industry. In the research of ultra-thin plate welding, such as foil with a thickness of less than 100 microns, fusion welding cannot be carried out, but YAG laser welding with special output power waveform is successful, which shows the broad future of laser welding. Japan also successfully developed YAG laser welding for the first time in the world for the maintenance of steam generator tubes in nuclear reactors, and also carried out gear laser welding technology in China.
2. Powder Metallurgy
With the continuous development of science and technology, many industrial technologies have special requirements for materials, and the materials manufactured by smelting and casting can not meet the needs. Due to the special properties and manufacturing advantages of powder metallurgy materials, they are replacing the traditional metallurgical materials in some fields, such as automobile, aircraft, tool and cutting tool manufacturing. With the increasing development of powder metallurgy materials, the connection between powder metallurgy materials and other parts is becoming more and more prominent, which limits the application of powder metallurgy materials. In the early 1980s, laser welding entered the field of powder metallurgy material processing with its unique advantages, which opened up a new prospect for the application of powder metallurgy materials. For example, the brazing method commonly used in the connection of powder metallurgy materials was used to weld diamond, which caused the melting and falling off of solder due to low bonding strength and wide heat affected zone, especially unable to adapt to high temperature and high strength requirements, Laser welding can improve the welding strength and high temperature resistance.
3. Automotive Industry
In the late 1980s, kW laser was successfully applied to industrial production. Now, laser welding production line has appeared in the automobile manufacturing industry on a large scale and has become one of the outstanding achievements of the automobile manufacturing industry. As early as the 1980s, European automobile manufacturers took the lead in using laser welding for sheet metal welding such as roof, body and side frame. In the 1990s, the United States unexpectedly introduced laser welding into automobile manufacturing. Although it started late, it developed rapidly. Italy uses laser welding in the welding and assembly of most steel plate components, and Japan uses laser welding and cutting processes in the manufacture of body panels. High strength steel laser welding assemblies are more and more used in the manufacture of automobile bodies because of their excellent performance. According to the statistics of American metal market, by the end of 2002, The consumption of laser welded steel structure will reach 70000t, which is three times higher than that in 1998. According to the characteristics of large batch and high degree of automation in automobile industry, laser welding equipment is developing in the direction of high power and multi-channel. In terms of process, Sandia National Laboratory of the United States and Pratt Witney jointly conducted research on adding powder metal and wire in the process of laser welding, and Bremen Institute of applied beam technology of Germany conducted a lot of research on laser welding aluminum alloy body frame. It is considered that adding filler in the weld is helpful to eliminate thermal cracks and improve welding speed, To solve the tolerance problem, the developed production line has been put into production in the factory.
