laser Cutting Technology
In recent years, laser technology has developed rapidly and has become a high-tech technology. Among them, laser cutting technology is widely used in many fields such as industrial production, manufacturing, and processing. Laser cutting technology is also rich in processing materials, which can cut metal, non-metal, plastic, wood, glass, and other materials. Moreover, laser cutting has low cost, high efficiency, and good quality of processed materials. This article introduces the principles, characteristics, types, methods, etc., of laser cutting technology in detail. The purpose is to give you a deeper understanding of laser cutting technology.
What is the laser?
The laser was discovered by the famous Jewish physicist Einstein in 1916. The laser is called the “fastest knife,” “the most accurate ruler,” and “the brightest light” by humans. The English name Light Amplification by Stimulated Emission of Radiation means “light amplification by stimulated radiation.” This name actually explains the main process of laser manufacturing. When the atom’s electrons absorb energy and then transition from a low energy level to a high energy level, and then fall from a high energy level to a low energy level, the released energy is released in the form of photons. The optical properties of the exciting photon beams are highly consistent. In this process, the photon beam is what we commonly call a laser. Compared with ordinary light sources, the laser has better monochromaticity, better directionality, and higher brightness.
Therefore, because of the advantages of lasers over ordinary light sources, it has a wide range of applications. For example, lasers are used in laser cutting, laser marking, laser welding, laser radar, fiber laser communication, laser ranging, laser weapons, laser beauty, laser scanning, LIF non-destructive testing technology, and other fields. So, how does the laser work? Below we will introduce the principle of laser in detail.
How does the laser work?
The essence of laser is the interaction of light and matter. Specifically, the matter is composed of microscopic particles. When microscopic particles change their motion state, they will absorb or radiate photons. Microscopic particles have a specific set of energy levels, and particles can only be in a state corresponding to a certain energy level at any time. When interacting with photons, the particle transitions from one energy level to another. As we know, a photon’s energy value is the difference in energy level at this time.
For example, a particle at a low energy level absorbs energy after an inelastic collision with a photon. At this time, the microscopic particles will jump to a higher energy level corresponding to this energy, and this process is called stimulated absorption. Besides, when microscopic particles are at a lower energy level that can accept other particles, even if there is no external action, the particles will spontaneously transition from a high-level excited state to a low-level ground state same time radiate photons, which is called spontaneous radiation. The light generated and amplified in the stimulated emission process is laser.
What are the classifications of lasers?
According to the type of gain medium, we usually divide lasers into solid-state lasers, liquid lasers, gas lasers, plasma lasers, and semiconductor lasers. In industrial production, we most commonly see CO2 laser cutting machine and fiber laser cutting machine. CO2 laser cutting machine is a common gas laser. The main gas working in the laser is carbon dioxide, and the auxiliary gas is nitrogen, xenon, and hydrogen. The gain medium of the fiber laser cutting machine is composed of optical fiber, the cutting material is wide, and the cutting quality is high. Semiconductor lasers are also called diode lasers and are also widely used. Below we focus on the application of laser in the cutting process.
What is the principle of laser cutting technology?
Focusing is the biggest feature of the laser. The energy density at the laser focus is huge. The focus position moves evenly with the laser head’s movement and then forms a continuous whole, which finally forms a cutting gap. The laser’s focus will be much greater than the energy reflected and dispersed by the processed parts. The part where the focus hits the workpiece will rise rapidly, which will intensify and make the material hollow. As the laser beam moves on the processing material, processing hollow holes will be continuously generated. Because the laser beam is skinny, it forms a tiny cutting seam.
To obtain better cutting quality, the manufacturing plant uses gas matching the processing material to cut. In this way, the material can be cut with less deformation and higher processing quality. For example, oxygen is used when processing steel parts. Compressed air is used when processing plastic materials. An inert gas such as argon is used for materials that are easy to burn cotton. The auxiliary gas can optimize the cutting effect and enter the nozzle to protect the focusing lens, preventing the cutting gas from entering the lens and making the lens dirty.
What are the characteristics of laser cutting technology?
Laser cutting focuses the beam through reflection and makes it act in a small area to obtain high-intensity heat to cut the material. Because of this, laser cutting technology has the following advantages:
What are the ways of laser cutting technology?
Laser cutting technology includes gasification cutting, melting cutting, melting cutting using oxygen, and cutting fissile materials. The following will focus on explaining these laser cutting technology methods and their advantages and disadvantages.
1. Gasification cutting.
Due to the laser’s energy focusing, large cutting power is generated, so the material will quickly heat up and directly vaporize into steam. During this process, there will be no heat melting stage.
After the part of the material is directly gasified, a small part is blown away by the auxiliary gas sprayed from the nozzle when processing the parts. Most of the material is blown away by the auxiliary gas as slag. The relative movement of the laser and the material forms a minimal cutting gap.
2. Melt cutting.
When the energy of the laser’s focus point exceeds a certain power, the laser-lasing part on the material begins to melt and evaporate, thereby forming a cutting gap. And once this small hole is formed, it will begin to absorb heat from the surrounding materials. As the laser moves on the material, the cut’s metal is melted to form a narrow cutting gap. Besides, the molten metal will be taken away by the gas ejected from the nozzle during processing.
3. Use oxygen to melt and cut.
In the process of laser cutting, the auxiliary gas we generally use is an inert gas. The reason is that the inert gas is not prone to chemical reactions and only needs to achieve slag blowing. If oxygen is used as an auxiliary gas for laser cutting technology, the material will chemically react with oxygen while being melted and burned by the laser. This produces another kind of energy besides the laser beam, and we usually call this laser cutting technique oxidative cutting. The specific working process is divided into the following two steps:
Step1: The laser focus point’s energy will heat the material to melt and burn, thereby forming a cutting gap and begin to absorb the heat of the surrounding material.The molten metal will be taken away by the gas ejected from the nozzle during processing.
Step2: If the auxiliary gas is faster, then the process of blowing away the residue and burning the material will be faster, and the processing speed will be faster.However, the oxidized slag will be quickly cooled down and adhere to the metal processing cut in this process. Thus, the quality of cutting is greatly reduced.
4. Cutting of fissile materials.
Some materials are relatively brittle and are prone to brittle fracture during processing. In this case, laser processing can be used. This processing method utilizes the laser beam’s highly focused feature to quickly heat the material in a small area, causing the material to undergo gradient thermal deformation and thus produce cracks. In the process of laser cutting, you can control the fission direction of the crack as long as you control the energy of the laser beam to obtain different cutting shapes. However, this laser cutting method is not suitable for processing relatively small angular shapes and huge enclosed parts. It should be noted that the laser speed for processing brittle materials with laser cutting technology should be fast, the power should not be too large, and the position of the laser focus should be controlled.
This article interprets the principles, characteristics, and processing methods of laser and laser cutting and believes that you can improve the cutting level and optimize the cutting quality. Compared with traditional processing methods, laser cutting technology does have great advantages, and it is also widely used in industrial production. BuyCNC is a laser equipment manufacturer from China. We provide 1010 6090 small-sized fiber laser cutter,3D fiber laser cutting machine, Plate and Tube fiber laser metal cutter,1500w 2000w 3000w 4000w all products for your choice. Come and consult for free.