Laser cutting is a widely used processing method in laser processing, and is a particularly important application technology in the laser processing industry. Laser cutting has been widely used in automotive, aviation, chemical, and other industrial sectors.
The principle of laser cutting is to melt and evaporate the workpiece by the energy released when the laser beam is irradiated on the surface of the workpiece to achieve the purpose of cutting and carving. Cutting accuracy is an important part of measuring the processing effect of laser cutting machine, but the laser cutting accuracy cannot depend on the equipment itself, but is composed of many factors. Among them, there are several important factors that affect the precision of laser cutting:
1. The size of the spot after the laser beam passes through the focus: the smaller the spot after the laser beam is gathered, the higher the laser cutting accuracy, especially the smaller the slit, the smaller the spot can reach 0.01 mm.
2. The positioning accuracy of the worktable determines the repetition accuracy of laser cutting. The higher the accuracy of the worktable, the higher the cutting accuracy.
3. The greater the thickness of the workpiece, the lower the accuracy and the greater the cutting seam. Because the laser beam is conical and the slit is also conical, the material with a thickness of 0.3 mm is much smaller than the slit with a thickness of 2 mm.
4. The workpiece material has certain influence on the laser cutting accuracy. In the same case, the cutting accuracy of different materials is also slightly different. Even for the same material, if the material composition is different, the cutting accuracy will also be different.
So, how can we achieve high accuracy in laser cutting? After years of practice, Xinquanli Laser has summarized several key technologies to improve laser cutting accuracy:
First, focus position control technology. The smaller the focal depth of the focus lens, the smaller the diameter of the focal spot, so it is very important to control the position of the focus relative to the surface of the material to be cut.
The second is cutting and piercing technology. For any thermal cutting technology, except for a few cases, which can start from the edge of the plate, a small hole must be drilled on the plate. In the laser stamping compound machine, a punch was used to punch a hole first, and then the laser was used to cut from the small hole.
The third is nozzle design and airflow control technology. When laser cutting steel, the oxygen and focused laser beam are shot to the material to be cut through the nozzle, thus forming a gas flow beam. The basic requirement for air flow is to enter the incision
The gas flow should be large and the speed should be high, so that enough oxidation can make the incision material fully conduct exothermic reaction; At the same time, there is enough momentum to eject the molten material.
Laser cutting has no burr, wrinkles and high precision, which is superior to plasma cutting. For many mechanical and electrical manufacturing industries, because the modern laser cutting system with microcomputer program can easily cut workpieces of different shapes and sizes (the drawing of workpieces can also be modified), it is often preferred over punching and molding processes; Although its processing speed is slower than that of die punching, it has no die consumption, no need to repair the die, and it also saves time to replace the die, thus saving processing costs and reducing product costs, so it is more cost-effective in general. This is also the reason for its popularity.
