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The principle of laser welding. Laser welding can be achieved using continuous or pulsed laser beam, the principle of laser welding can be divided into the heat conduction welding and laser deep penetration welding. Power density of less than 104 ~ 105 W/cm2, the heat conduction welding, the melt depth, the welding speed is slow; power density greater than 105 ~ 107 W/cm2, when the metal surface to heat the role concave into a "hole" to form a deep penetration , welding speed, aspect ratio features. The heat conduction laser welding principle as follows: laser radiation heating to be processed surface, the surface heat transfer through the heat transfer-oriented internal diffusion, by controlling the laser pulse width, energy, peak power and repetition frequency of laser parameters.  green laser pointer   can remotely turn over the pieces of page of the documents in computers.
So that the workpiece to melt, the formation of specific bath. Gear welding and metallurgy sheet metal welding laser welding machine is mainly involved in laser deep penetration welding. The following highlights the principle of laser deep penetration welding. Deep penetration laser welding is generally a continuous laser beam to complete the connection of the material, metallurgical physical processes of electron beam welding is very similar to the energy conversion mechanism is accomplished through the "holes" (Key-hole) structure. In a sufficiently high power density laser irradiation, the material evaporation and the formation of holes. The hole full of steam like a blackbody, including nearly all of the incident beam energy, the hole cavity equilibrium temperature of 25 0C, and the heat from high temperature hole cavity outer wall to pass out, so that the molten metal around the hole cavity surrounded. Remote control technology is adopted for    laser pointer .
Holes filled with wall material in the beam by the continuous evaporation produced high-temperature steam, and small hole walls surrounded by molten metal, liquid metal is surrounded by solid material (and in most of the conventional welding process and laser conduction welding, the energy is first deposited in workpiece surface, and then transported to rely on passing internal). Hole wall outside the liquid flow and parietal surface tension and hole cavity continuous steam pressure stalemate and maintain homeostasis. Beam continuously into the holes, holes outside of the material in a continuous flow, with the beam move the holes is always in the flow of steady-state. That is, the holes and around the hole wall of the molten metal to move forward with the leading beam forward speed, the molten metal filling the void left by the holes away and followed by condensation, so the formation of weld. There is no need for   green laser      to install any drive.
The above process all of this happened so fast, so that the welding speed can easily reach several meters per minute. The deep penetration laser welding process parameters. The laser power. Laser welding, a laser energy density threshold, below this value, the penetration depth is very shallow, once they reach or exceed this value, the penetration will be greatly improved. Only when the laser power density on the workpiece exceeds the threshold (and related materials), the plasma will produce, which marks the stable deep penetration carried out. If the laser power is below this threshold, the workpiece surface melting occurs only, that is welded to the stability of heat conduction. When the laser power density is near the critical condition of the holes formed, deep penetration and conduction welding alternately become unstable welding process, resulting in the penetration depth fluctuations.   usa green laser pointer    can show the pictures on the projection screen.
Laser deep penetration, the laser power while controlling the penetration depth and welding speed. Welding penetration is directly related to the beam power density, and is a function of incident beam power and beam focal spot. In general, the increase of a certain diameter of the laser beam penetration with the beam power is increased. Beam focal spot. The beam spot size of laser welding one of the most important variable, because it determines the power density. For high-power laser, its measurement is a problem, despite a lot of indirect measurement techniques. Diffraction limit of the beam focus spot size based on light diffraction theory calculations, but due to the existence of the focusing lens aberrations, the actual spot than the calculated value is too large. Most of    green laser pointer   are wrapped with plastic or metal.