Remote laser cutting system with customized laser beam pattern

Regarding the mechanism of high-power laser generating vapor pressure, it was known as early as decades ago during laser drilling and keyhole penetration laser deep penetration welding. The local vapor pressure is the driving mechanism of penetrating drilling, and it is used For creating and maintaining keyholes in welding. Keyhole penetration laser cutting has a history of 20 years. At that time, a group of scientists at the Fraunhofer Institute of Laser Technology studied the use of CO2 lasers for high-speed cutting of sheet metal. However, the use of CO2 lasers for keyhole laser cutting is limited to very thin plates. This is due to the formation of strong plasma in the keyhole, which also occurs in high-power CO2 laser welding.　　 The focusing performance and wavelength of high-brightness fiber lasers enable this type of laser to perform keyhole cutting on thick plates, because fiber lasers can cut much faster than CO2 lasers. Because it can more efficiently remove the melt from the center line of the cutting front, keyhole cutting is more efficient than usual laser cutting; in the former process, the melted material will flow down in front of the laser beam. This makes the thickness of the molten layer thinner, thus ensuring effective heat transfer from the molten surface. The melt front on the surface absorbs the laser and requires energy to melt more material. However, in keyhole cutting, the molten fluid around the laser beam can cause quality problems. The melt flows away from the cutting side, which will deteriorate the cutting quality, because the cutting speed of the fiber laser is very fast, but when the cutting thickness increases, the cutting quality is not high.　　 In typical laser cutting and advanced keyhole cutting, the coaxial gas assist method is the power to remove the molten material; the incision must be enlarged to reduce the pressure through the incision. Here, the pressure obtained by laser irradiation is greater, and the entire incision is subjected to huge pressure. Therefore, a new method of customizing the laser beam can be designed completely according to the optical path limitation, which can cut a narrower incision than the cutting method of an advanced laser cutting machine. (The above is edited by laser cutting machine, see www.gnlaser.com for details)