With the continuous progress and development of science and technology, laser cutting technology is becoming more and more mature. Today, I will introduce four types of laser cutting technology.
Laser cutting is one of the popular methods of metal processing at present. Its principle is to use the focused high-power density laser beam to irradiate the workpiece, so that the irradiated material can quickly melt, vaporize, ablate or reach the ignition point. At the same time, with the help of the high-speed airflow coaxial with the beam, the molten material is blown away, so as to realize the cutting of metal workpiece.
According to the thermophysical properties and auxiliary gas properties of processing materials, laser cutting can be divided into four types: laser vaporization cutting, laser melting cutting, laser oxygen cutting and laser controlled fracture.
1、 Laser vaporization cutting
Using high-energy and high-density laser beam to heat the workpiece, the temperature of the cutting material rises rapidly, reaching the boiling point of the material in a short time, skipping the melting step and directly starting to vaporize to form steam. At the same time that the steam is ejected, a notch is formed on the cutting material.
It is mainly used for cutting extremely thin metal materials and non-metallic materials such as paper, cloth, wood, plastic and rubber. Its advantage is that the cutting quality is high and the material consumption is small.
2、 Laser melting cutting
Use laser to heat metal materials and melt them, blow out inert gases, such as nitrogen, through the nozzle coaxial with the beam, and discharge the molten liquid metal by relying on the strong pressure of the gas. The advantages of laser melting cutting are that the cutting edge is relatively smooth, generally no secondary treatment is required, the laser energy requirements are high, and the gas pressure is large. Suitable for cutting stainless steel, titanium, aluminum and alloy metals.
3、 Laser oxygen cutting
The principle of laser oxygen cutting is similar to oxyacetylene cutting. It uses laser as preheating heat source and active gas such as oxygen as cutting gas. On the one hand, the ejected gas has an oxidation reaction with the cutting metal, releasing a large amount of oxidation heat; On the other hand, the molten oxide and melt are blown out of the reaction zone to form a notch in the metal. The cutting speed is fast, which is mainly applicable to the cutting of carbon steel and metal materials.
4、 Laser controlled fracture
Laser controlled fracture is to use the steep temperature distribution generated by small laser power grooving to generate local thermal stress in brittle materials, making the materials break along the groove. Higher power will cause the workpiece surface to melt and damage the cutting edge. It is mainly suitable for cutting brittle materials such as silicon wafer and glass.