Industrial Application of High-power Fiber-coupled Semiconductor Lasers
Semiconductor lasers are lasers using semiconductor materials as the working medium. Such lasers have the characteristics of small size, light weight, long service life, simple structure, and robustness. With the development of industry, the laser power of semiconductor lasers has climbed to the kilowatt level, and has been applied in laser brazing, laser cladding, laser metal welding, and has certain advantages.
Laser Brazing
Laser brazing has always been an advantage of high-power semiconductor lasers. Although the semiconductor laser energy density is slightly lower than that of a fiber laser, its energy distribution is uniform, and the solder melts evenly during the brazing process and is not prone to spatter. The laser brazing market in the automotive industry has been dominated by semiconductor fiber-coupled lasers.
Laser Cladding
Laser cladding can improve the wear resistance and corrosion resistance of metal parts. Laser cladding cooling speed (up to 106K / s), is a rapid solidification process, easy to get fine-grained or equilibrium state can not be obtained in the new phase, such as non-stable phase, amorphous and so on. At the same time, the dilution rate of the coating is low (generally less than 5%), and it is in solid metallurgical or interface diffusion with the substrate. By adjusting the laser process parameters, a good coating with low dilution rate can be obtained, and the coating composition and dilution can be obtained. Controllable. At the same time, the laser cladding heat input and distortion are small, especially when using high power density fast cladding, the deformation can be reduced to the assembly tolerance of the part.
Laser Metal Welding
High-power semiconductor lasers have high welding strength during the welding process, and the weld smoothness and smoothness do not require high post-processing efficiency. They are widely used in the automotive, metallurgy, defense, and military industries. For example, the electro-optical conversion efficiency of direct semiconductor lasers produced by Kaplan Corporation is as high as 50%. It is predicted that direct semiconductor lasers will be a powerful complement to fiber lasers in the field of welding due to their own high-efficiency photoelectric conversion efficiency and performance characteristics after several years.
Future prospects
With the continuous development of semiconductor laser chip technology and integration technology, the power of high-power semiconductor lasers will become higher and higher, and the beam quality will also improve year by year. The power of high-power semiconductor lasers currently used in laser manufacture can reach 6 kW or even higher. The light beam can be coupled into optical fibers with a core diameter of 0.6 mm, and a 1 kW beam can be coupled into optical fibers with a core diameter of 0.3 mm. Therefore, high-power semiconductor lasers will be used as a direct energy source in the field of material processing that requires high power density.