Five factors affecting the quality of CO2 laser cutting

1 Motivation model. The carbon dioxide laser uses electrodes to excite carbon dioxide gas to generate laser light. According to the installation position of the metal electrode, it can be divided into direct current excitation and radio frequency excitation.

　　 2 laser frequency. The laser output is divided into pulse output and continuous output. The laser used for cutting and welding mainly adopts the pulse output method. The pulse frequency mainly affects the cutting speed and the roughness of the cut. To obtain high-speed cutting, high frequency is essential. At present, the frequency of carbon dioxide lasers produced by most manufacturers is within 5000 Hz.

　　3 beam divergence angle. Strictly speaking, the beam divergence angle is not part of the content of the laser, but because the laser mode has a great influence on the far-field divergence angle, we will discuss it here. The influence of the beam divergence angle on the cutting quality is reflected in the width and slope of the incision. The smaller the divergence angle, the narrower the incision width, the smaller the slope, and the higher the quality.

　　4 laser mode. It is one of the most important indicators to measure laser quality. It can be divided into single mode, base mode and multimode. The fundamental mode is the TEM00 mode, and its exponents on the X and Y axes are both 0, so it is an ideal dot. The laser with TEM00 mode can obtain the smallest beam diameter, and the smallest slit and faster cutting speed in the cutting process due to its small spot. The multi-mode has a non-zero index in the XY direction, and its beam quality is poor. Generally, it is only used for welding and not for cutting.

　　 5 laser cutting machine, laser power. Including peak power, energy stability and other factors. Different powers can cut through different thicknesses in the cutting of metal sheets. Take a 4KW laser as an example. It can cut 20mm thick carbon steel plates, or 15mm stainless steel and 10mm aluminum alloys. Lasers above 5KW can cut 25mm thick carbon steel. Stainless steel can reach up to 20mm. Another indicator of power is power stability. Excellent cutting quality must be an excellent cut throughout. Long-term production is also a very important test for lasers. DC-excited lasers cause power attenuation under long-term working conditions due to electrode ablation. In addition, because the vacuum pump and turbo pump of some lasers are lubricated with lubricating oil, the lubricating oil contaminates the laser resonator cavity and shortens the life of the laser.