Nowadays, the application of fiber optic cutter has spread to all walks of life and become the leader in laser processing equipment. Then under the trend that it is so popular, you have to understand its four unique cutting processes. Blow,Perfect laser will popularize the four cutting processes of fiber optic cutters.
1. Gasification cutting
During the gasification cutting process, the rate at which the surface temperature of the material rises to the boiling point is so fast that it is sufficient to avoid the phenomenon of melting around the material caused by heat transfer. Then Some materials vaporize into steam and disappear, while some materials are blown away from the bottom of the slit as ejecta by auxiliary gas flow. In this case, very high laser power is required. In order to prevent the material vapor from condensing onto the slit wall, the thickness of the material must not exceed the diameter of the laser beam. Therefore the process is only suitable for applications without molten material, it is actually only applicable to the small field of use of iron-based alloys. This processing cannot be applied to materials such as wood and certain ceramics, as well as materials that are not melted and are therefore less likely to re condense the material vapor. In addition, these materials typically require thicker cuts.
In gasification cutting, Optimal beam focus depends on material thickness and beam quality. Laser power and gasification heat have a certain influence on the optimal focus position. In the case of a certain thickness of the sheet, the maximum cutting speed is inversely proportional to the vaporization temperature of the material. The required laser power density depends on the material, depth of cut and beam focus position. In the case of a certain thickness of the sheet, assuming sufficient laser power, the maximum cutting speed is limited by the gas jet velocity.
2. Melt cutting
In laser melt cutting, the workpiece is partially melted and the molten material is ejected by means of a gas stream. Because the transfer of material occurs only in its liquid state, the process is called laser melt cutting. The laser beam is matched with a high-purity inert cutting gas to cause the molten material to leave the slit, and the gas itself is not involved in cutting. Laser melt cutting can achieve higher cutting speed than gasification cutting, and the energy required for gasification is usually higher than the energy required to melt the material. In laser melt cutting, the laser beam is only partially absorbed. The maximum cutting speed increases as the laser power increases, and decreases inversely proportionally as the thickness of the sheet increases and the material melt temperature increases. In the case of a constant laser power, the limiting factor is the air pressure at the slit and the thermal conductivity of the material. Laser melt cutting provides an oxidative cut for the iron material and titanium metal, resulting in a laser power density that is melted but less than vaporized.
3. Oxidative melting cutting (laser flame cutting)
Melting and cutting generally use inert gas. If replaced by oxygen or other reactive gases, the material is ignited under the illumination of the laser beam, and a strong chemical reaction with oxygen generates another heat source to further heat the material, which is called oxidative melting cutting.
Due to this effect, for structural steels of the same thickness, the cutting rate obtainable by this method is higher than that of melt cutting. On the other hand, this method may have worse cut quality than melt cut. In fact, it produces wider slits, significant roughness, increased heat affected zone and worse edge quality. Laser flame cutting is not good when machining precision models and sharp corners (there is a possibility of burning off sharp corners). The thermal effect can be limited by changing the pulse mode laser, which determines the cutting speed. In the case of a constant laser power, the limiting factor is the supply of oxygen and the thermal conductivity of the material.
4. Control fracture cutting
For brittle materials that are easily damaged by heat, high-speed, controlled cutting by laser beam heating, is called controlled fracture cutting. This cutting process is mainly: the laser beam heats a small area of the brittle material, causing a large thermal gradient and severe mechanical deformation in the area, causing the material to form cracks. As long as a balanced heating gradient is maintained, the laser beam can direct the crack to occur in any desired direction.
The above is a detailed description of the four cutting processes of the fiber optic cutter. I believe that after reading this article, you can understand the unique laser cutting process of gasification cutting, melt cutting, oxidation cutting, and controlled fracture cutting.