After melting occurs rapidly and the vaporized
Laser welding is the use of high energy density laser light source is irradiated material connection, so that the separation and laser energy absorbing material together forming a molten pool, solidified in the subsequent cooling process together so as to connect together . High power laser welding of the laser there are two common: CO2 laser and solid / fiber laser, the wavelength of the former is 10.6 m, or a wavelength of 1.06 / 1.07μm, are in the infrared, invisible to the naked eye.
1. Laser welding body noun
Common welding principle is actually liquefied metal, and then is cooled with the solvent. Car body is formed by welding four steel plates vertically and horizontally, Common are spot welded, to a plate connected together by a weld obtained.
is the physical principles of laser welding using a laser temperature, the molecular structure of the two steel plates disrupted, two molecules to rearrange such that the steel sheet molecule as one solution. The actual operation is the use of a laser beam generated by a polarizer reflection, it focused on the focusing means can be enormousThe amount of the beam. Laser beam diameter at the focal point within a range of 0.2-0.6 mm, to obtain more than 106-108 W / cm light intensity, focus close to the workpiece, the workpiece surface to achieve the change in physical melt-bonded.
So the laser welding two steel plates into a steel plate, is therefore compared with ordinary welding, has a higher strength.
2. The characteristics of laser welding body
What are the advantages of laser welding technology?
The main laser welding in areas where heating and precisely controllable, small welding distortion, welding speed and other characteristics. Laser welding and common electrical contrast, the spot diameter of the laser welding can be precisely controlled, typically irradiation (energy in the form from the center to the edge of the surface material spot diameter in the range 0.2-0.6mm, and the higher the closer the position of the energy center spot exponential decay, i.e., a Gaussian distribution), laser welding bead width of 2mm or less can be controlled. And the width of the arc of the arc welding precisely controlled and not much larger than the laser spot diameter, arc far greater than the width of the weld laser welding, typically in more than 6mm. Since the energy of the laser welding is concentrated to a small molten material, small total required heat, the welding deformation, welding speed.
Compared with the resistance spot laser welding, how strong? A laser welding joint is elongate continuous line, while the resistance spot welding joint is a row of discrete dots slightly concave. If the laser welding head zipper access, like the two lapel clothes together, and that resistance spot welding joints like a buckle clasp clothes. Laser welding the weld metal is obtained through the rapid solidification, the grain (the basic unit of the metal, the metal will be appreciated that a cell) is more fine, help to improve the strength of the weld metal, the strength of the weld metal laser welding little higher than the strength of resistance spot weld metal. And do not forget, resistance spot welding joints is a series of discrete points, just go and take part than on the laser welding have been over, but the welding, welding and place on those also did not “drag”, and that on average resistance spot welding, but it is more than the laser welding. Thus, for the same length of the weld joint, the intensity of the laser welding is higher than the resistance spot welding.
the laser welding head
Resistance Spot Welding
3 laser welding body safer?
Although the joint strength than the resistance spot welding, laser welding, however, but still higher than the base metal, the weakest link in the entire body is to weld the weld heat affected zone of the base material. That is the base metal is the weakest link, so in the event of the vehicle body with great force, the metal base material are damage occurs in most cases, instead of welded joints. Foreign body is manifested by the presence of a short piece of the base metal plate, so that the laser welding and resistance spot welding strength of the body almost no difference. Thus laser welding body when not affected by external force and safer than resistance spot welding body.