Metal laser cutting machine is a kind of machine made of metal, which uses laser technology to cut. Now it is used in many places, which uses laser. Do you know what is laser? Laser is a kind of beam with very strong release ability. Laser can achieve extremely fast cutting in a very short time. Metal cutting machine is very labor-saving and time-saving. Do you know the principle of metal laser cutting machine? Next let's take a look at the principle of metal laser cutting machine.
Laser cutting is to use the focused high-power density laser beam to irradiate the workpiece, so that the irradiated material can melt, vaporize, ablate or reach the ignition point rapidly. At the same time, the molten material can be blown off by the high-speed air flow coaxial with the beam, so as to realize the workpiece cutting. Laser cutting is one of the hot cutting methods.
Laser cutting can be divided into four categories: laser vaporization cutting, laser melting cutting, laser oxygen cutting, laser scribing and controlled fracture.
1) laser vaporization cutting
The high energy density laser beam is used to heat the workpiece, so that the temperature rises rapidly, and the boiling point of the material is reached in a very short time, and the material begins to vaporize to form vapor. These vapors are ejected at a very high speed. When the vapors are ejected, a cut is formed on the material. The heat of vaporization of materials is generally very large, so laser vaporization cutting needs a lot of power and power density.
Laser vaporization cutting is mainly used for cutting extremely thin metal materials and non-metal materials (such as paper, cloth, wood, plastic and rubber, etc.).
2) laser melting cutting
During laser melting and cutting, the metal materials are melted by laser heating, and then the non oxidizing gases (AR, he, N, etc.) are blown through the nozzle which is coaxial with the beam of light, and the liquid metal is discharged by the strong pressure of the gas to form the incision. Laser melting cutting does not need to completely vaporize the metal, the energy required is only 1 / 10 of vaporization cutting.
Laser melting cutting is mainly used for cutting materials or active metals that are not easy to oxidize, such as stainless steel, titanium, aluminum and their alloys.
3) laser oxygen cutting
The principle of laser oxygen cutting is similar to that of oxyacetylene cutting. It uses laser as preheating heat source and oxygen as cutting gas. On the one hand, the injected gas interacts with the cutting metal to produce oxidation reaction and release a large amount of oxidation heat; on the other hand, the molten oxide and molten substance are blown out of the reaction area to form a notch in the metal. Because the oxidation reaction in the cutting process produces a lot of heat, the energy needed for laser oxygen cutting is only 1 / 2 of the melting cutting, and the cutting speed is much faster than that of laser vaporization cutting and melting cutting. Laser oxygen cutting is mainly used for carbon steel, titanium steel and heat treatment steel and other easily oxidized metal materials.
4) laser scribing and controlled fracture
Laser scribing is to use high energy density laser to scan the surface of brittle materials, so that the materials evaporate a small groove when heated, and then apply a certain amount of pressure, the brittle materials will crack along the small groove. Generally, Q-switched laser and CO2 laser are used for laser dicing.
Controlling fracture is to use the steep temperature distribution produced by laser notching to generate local thermal stress in brittle materials, which makes the materials break along the small grooves.
The above is the introduction of the principle of the metal laser cutting machine. The metal laser cutting machine is a kind of automatic typesetting machine, which can save a lot of materials, and the materials cut by the metal laser cutting machine are very flat, and its cut is very smooth. The laser cutting machine can reduce the manufacturing cost and processing cost.