Laser welding can be achieved using continuous or pulsed laser beams. The principles of laser welding can be divided into heat conduction welding and laser deep penetration welding. The power density is less than ~ /, which is heat conduction welding. At this time, the penetration depth is shallow and the welding speed is slow. The principle of laser welding is that laser radiation heats the surface to be processed, and the surface heat diffuses to the interior through thermal conduction. By controlling the width, energy, power and frequency of the laser pulse, etc. Parameters cause the workpiece to melt to form a specific molten pool.
Laser deep penetration welding generally uses a continuous laser beam to complete the connection of materials. Its metallurgical physical process is very similar to that of electron beam welding, and the energy conversion mechanism is completed through small holes. Under the irradiation of high-power density laser, the material evaporates to form a small hole. This small hole filled with vapor is like a black body, absorbing almost all the incident light energy. The heat is transferred from the outer wall of this high-temperature cavity to surround the cavity. of metal melted. The wall material under the beam irradiation continuously evaporates to produce high-temperature steam. The wall surface tension formed by the liquid flow outside the hole wall maintains a dynamic balance with the steam pressure continuously generated in the hole cavity. The beam continuously enters the small hole, and the small hole is always in a stable state of flow. The molten metal surrounding the hole wall moves forward as the leading beam advances. The molten metal fills the gap left after the small hole is removed and condenses accordingly. Welding A seam is formed. This article originates from First〈/?〉, please indicate the source when reprinting.
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