Introduction to the principle and classification of metal cutting machine:
1、 Principle
The laser cutting machine uses the focused high power density laser beam to irradiate the workpiece, so that the irradiated material can rapidly melt, evaporate, corrode or reach the ignition point, and uses the high speed gas flow coaxial with the beam to blow away the molten material to realize the cutting of the workpiece. Laser cutting is one of the thermal cutting methods.
2、 Classification
Laser cutting can be divided into four categories: laser vaporization cutting, laser melting cutting, laser oxygen cutting, laser slicing and controlled fracture.
1. Laser vaporization cutting
Use the energy density laser beam to heat the workpiece, make the temperature rise rapidly, reach the boiling point of the material in a short time, and the material begins to evaporate to form steam. This kind of steam injection speed is very fast, and at the same time, a notch is formed on the material. The evaporation heat of materials is generally large, so laser evaporation cutting requires a large power and power density. Laser evaporation cutting is mainly used for non-metallic materials (such as paper, cloth, wood, plastic and rubber).
2. Laser melting and cutting
When the laser is melting and cutting, the laser is used to heat and melt the metal material, and then the nozzle coaxial with the beam is used to spray non-oxidizing gas. (Ar, He, N, etc.) Liquid metal is discharged by strong air pressure to form a cut. Laser melting cutting does not require all evaporation of metal, and the required energy is only 1/10 of evaporation cutting. Laser melting cutting is mainly used to cut some non-oxidizable materials or active metals, such as stainless steel, titanium, aluminum and their alloys.
3. Laser oxygen cutting
The principle of laser oxygen cutting is similar to oxyacetylene cutting. It uses laser as preheating heat source and oxygen and other active gases as cutting gas. On the one hand, the sprayed gas reacts with the cutting metal and releases a large amount of oxidation heat;
On the other hand, molten oxides and molten substances are blown out of the reaction zone to form a notch in the metal. The energy required by laser oxygen cutting is only 1/2 of that of melting cutting, and the cutting speed is far greater than that of laser vaporization cutting and melting cutting, because the oxidation reaction generates a lot of heat during the cutting process. Laser oxygen cutting is mainly used for carbon steel, titanium steel, heat treatment steel and other easily oxidized metal materials.
4. Laser sectioning and controlled fracture
The source energy density laser is used to scan the surface of brittle material, heat the material to evaporate a small groove, and then apply some pressure to make the brittle material crack along the small groove. Laser slicing lasers are generally Q-switched lasers and CO2 lasers. The controlled fracture is to use the steep temperature distribution generated by the laser groove to generate local thermal stress in the brittle material and make the material break along the small groove.
The above is the principle introduction of metal laser cutting machine. The metal laser cutting machine is a mechanical device that can automatically typeset, which can save a lot of materials. The material cut by the metal laser cutting machine is very smooth, and the cut is very smooth. Metal laser cutting machine can reduce the processing cost. Most processing manufacturers will choose this equipment, which can greatly reduce the manufacturing and processing costs of enterprises.
