1. Manufacturing
Laser tailor welding technology has been widely used in foreign car manufacturing. According to statistics, there were more than 100 laser tailor welding production lines in the world in 2000, with an annual output of 70 million tailor-welded blanks for car components, and continued to grow at a relatively high speed . Domestically produced and imported models also adopt some cut blank structure. Japan uses CO2 laser welding instead of flash butt welding to connect rolled steel coils in the steel industry. Research on ultra-thin plate welding, such as foils with a thickness of less than 100 microns, cannot be welded, but through YAG with a special output power waveform The success of laser welding shows the broad future of laser welding. Japan also successfully developed YAG laser welding for the maintenance of thin tubes of steam generators in nuclear reactors for the first time in the world, 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 materials manufactured by smelting and casting methods can no longer meet the needs. Due to the special performance and manufacturing advantages of powder metallurgy materials, they are replacing traditional smelting and casting materials in some fields such as automobiles, aircrafts, and tool and cutting tool manufacturing. With the increasing development of powder metallurgy materials, the problem of its connection with other parts Appears increasingly prominent, so that the application of powder metallurgy materials is limited. In the early 1980s, laser welding entered the field of powder metallurgy material processing with its unique advantages, which opened up new prospects for the application of powder metallurgy materials. For example, the brazing method commonly used in powder metallurgy material connection is used to weld diamond. Low strength, wide heat-affected zone, especially not suitable for high temperature and high strength requirements, causing the solder to melt and fall off. Laser welding can improve welding strength and high temperature resistance.
3. Automobile industry
In the late 1980s, kilowatt-level lasers were successfully applied to industrial production. Today, laser welding production lines have appeared on a large scale in the automobile manufacturing industry, becoming one of the outstanding achievements of the automobile manufacturing industry. European automobile manufacturers took the lead in using laser welding for roof, body, side frame and other sheet metal welding as early as the 1980s. In the 1990s, the United States competed to introduce laser welding into automobile manufacturing. Although it started late, it developed rapidly. Italy uses laser welding in the welding assembly of most steel plate components. Japan uses laser welding and cutting processes in the manufacture of body panels. High-strength steel laser welding assemblies are used more and more in automobile body manufacturing due to their excellent performance. More, according to the US metal market statistics, by the end of 2002, the consumption of laser-welded steel structures will reach 70,000t, a 3-fold increase from 1998. According to the characteristics of large batch and high degree of automation in the automobile industry, laser welding equipment is developing in the direction of high power and multi-channel. In terms of technology, the Sandia National Laboratory of the United States and PrattWitney jointly conducted research on adding powdered metal and wire during laser welding. The Institute of Applied Beam Technology in Bremen, Germany has conducted a lot of research on the use of laser welding aluminum alloy body frames. It is believed that adding filler metal to the weld can help eliminate thermal cracks, increase welding speed, and solve tolerance problems. The developed production line has been put into production in the factory.
4. Electronic industry
Laser welding is widely used in the electronics industry, especially in the microelectronics industry. Due to the small heat-affected zone, rapid heating concentration and low thermal stress of laser welding, it is showing unique advantages in the packaging of integrated circuits and semiconductor device housings. In the development of vacuum devices, laser welding has also been applied, such as Molybdenum focusing electrode and stainless steel support ring, fast hot cathode filament assembly, etc. The elastic thin-walled corrugated sheet in the sensor or temperature controller has a thickness of 0.05-0.1mm, which is difficult to solve by traditional welding methods. TIG welding is easy to weld through, and the plasma stability is poor. There are many influencing factors, but laser welding works well and is widely used. Applications.
5. Biomedicine
Laser welding of biological tissue began in the 1970s. The successful welding of fallopian tubes and blood vessels with laser welding and its superiority have led more researchers to try to weld various biological tissues and extend it to other tissues. Domestic and foreign research on laser welding of nerves is mainly focused on laser wavelength, dose and its effect on functional recovery and selection of laser solder. Liu Tongjun conducted basic research on laser welding small blood vessels and skin. Welding studies of the common bile duct in rats were performed. Compared with the traditional suturing method, the laser welding method has the advantages of fast anastomosis, no foreign body reaction during the healing process, maintaining the mechanical properties of the welded part, and the repaired tissue grows according to its original biomechanical properties. be more widely used.
6. Other fields
In other industries, laser welding is also gradually increasing, especially in the welding of special materials. A lot of research has been done in China, such as laser welding of BT20 titanium alloys, HEl30 alloys, Li-ion batteries, etc. Germany has developed a method for flat glass. new technology of laser welding.