What materials can the fiber laser cutting machine cut
26 Mar , 2021
The laser beam irradiates the surface of the workpiece to make the workpiece reach the melting point or boiling point, while the high-pressure gas coaxial with the beam blows away the molten or vaporized metal.
The laser cutting machine
focuses the laser light emitted from the laser into a high-power density laser beam through the optical path system. The laser beam irradiates the surface of the workpiece to make the workpiece reach the melting point or boiling point, while the high-pressure gas coaxial with the beam blows away the molten or vaporized metal. As the relative position of the beam and the workpiece moves, the material will finally form a slit, so as to achieve the purpose of cutting.
Laser cutting processing is to replace the traditional mechanical knife with an invisible beam. It has the characteristics of high precision, fast cutting, not limited to cutting patterns, automatic typesetting, saving materials, smooth cuts, and low processing costs. It will be gradually improved or replaced Traditional metal cutting process equipment.
So, what materials can the fiber laser cutting machine cut? What material does the laser cutting machine cut effectively?
During the cutting process of the laser cutting machine, the beam is focused by the lens of the cutting head into a small focal point, so that the focal point can reach a high power density, and the cutting head is fixed on the z-axis. At this time, the heat input by the beam far exceeds the part of the heat reflected, conducted or diffused by the material, and the material is quickly heated to the melting and vaporization temperature. At the same time, a high-speed airflow will melt from the coaxial or non-coaxial side. And the vaporized material is blown out to form holes for cutting the material. With the relative movement of the focus and the material, the hole forms a continuous slit with a very narrow width to complete the cutting of the material.
We know that the initial absorption rate of the 10.6um laser beam by metal is only 0.5%~10%. However, when a focused laser beam with a power density of more than 106w/cm2 irradiates the metal surface, it can be very effective in microseconds. Almost the surface starts to melt. The absorption rate of most metals in the molten state rises sharply, generally by 60% to 80%. Fiber laser cutting machine has good processing effect on the following materials.
1. Titanium and alloys
Pure titanium can well couple the heat energy converted by the focused laser beam. When the auxiliary gas is oxygen, the chemical reaction is fierce, and the cutting speed is faster, but it is easy to form an oxide layer on the cutting edge, and accidentally can cause overburn. For the sake of safety, it is better to use air as the auxiliary gas to ensure cutting quality. For example, the laser cutting quality of titanium alloy commonly used in the aircraft industry is better. Although there will be a little sticky residue at the bottom of the slit, it is easy to clean.
2. Nickel alloy
Nickel-based alloys are also called super alloys, and there are many varieties. Most of them can be oxidized fusion cutting.
3. Carbon steel, stainless steel
Modern laser cutting machines
can cut carbon steel plates with a maximum thickness of up to 20mm. The cutting seam of carbon steel can be controlled within a satisfactory width by using the oxidation melting cutting mechanism, and the cutting seam for thin plates can be as narrow as about 0.1mm. Laser cutting is an effective processing tool for the manufacturing industry that uses stainless steel sheet as the main component. Under the strict control of the heat input in the laser cutting process, the heat-affected zone of the trimming can be restricted from becoming small, thereby effectively maintaining the good corrosion resistance of such materials.
4. Alloy steel
Most alloy structural steels and alloy tool steels can be used to obtain good trimming quality by laser cutting. Even for some high-strength materials, as long as the process parameters are properly controlled, straight, non-sticky slag cutting edges can be obtained. However, for tungsten-containing high-speed tool steel and hot mold steel, there will be erosion and slag sticking during laser cutting machine processing.
5. Aluminum and alloy, copper and alloy
Aluminum cutting is a melting laser cutting mechanism, and the auxiliary gas used is mainly used to blow away the molten product from the cutting area, and usually a better cut surface quality can be obtained. For some aluminum alloys, attention should be paid to prevent the occurrence of micro-cracks between the surface of the slit. Pure copper (red copper) basically cannot be cut with CO2 laser beam due to its high reflectivity. Brass (copper alloy) uses higher laser power, and the auxiliary gas uses air or oxygen, which can cut thinner plates.
Adjust the machine tool assembly to improve the cutting effect.
1) Rail installation:
When installing the rails, keep the rails parallel. When the laser equipment leaves the factory, it needs to be debugged repeatedly to ensure the cutting effect of each equipment. If the guide rails are not parallel, there will be resistance when the machine is running, and most of the cut objects have serrated edges, so the Y-axis guide rails need to be parallel.
2) The installation position of the beam and the coupling is not good: During the installation of the beam and the mechanical coupling, if the screw is not locked, the lock is inclined or loose, it will affect the cutting effect of the laser cutting machine.