Factors Affecting the Cutting Quality
The parameters of Laser Cutting Machine are very important as it affects the quality of ,cutting. How should these professional performance parameters be considered when choosing a Laser Cutting Machine?
Effect of Air Pressure
The Laser Cutting Machine can cool the heat affected area by blowing the slag by the auxiliary air pressure. Auxiliary gas includes oxygen, compressed air, nitrogen and inert gas. For some metal and non-metal materials, inert gas or compressed air is usually used to prevent the material from burning, such as cutting aluminum alloy materials. Most metal materials use active gas (such as oxygen), because oxygen can oxidize the metal surface and increase the cutting efficiency. When the auxiliary air pressure is too high, eddy currents will appear on the surface of the material, which will weaken the ability of the material to remove the melt, resulting in a larger cutting gap and rough cutting surface; when the air pressure is too low, the melt can not be blown completely and the bottom surface is bound to the slag.
Effect of Laser Power
Laser Cutting Machine, the size of its power has great influence on cutting speed, cutting width, cutting thickness and cutting quality. The required strength depends on the properties of the material and the cutting mechanism. For example, materials with good thermal conductivity, high melting point, and high reflectivity require greater laser power. Generally, under other conditions, laser cutting has the best laser power for cut quality. Further reduction or increase in power will cause slag to hang or overheat, resulting in a decrease in machining quality. In addition, as the discharge voltage increases, the input peak power increases, the spot diameter increases, and the slit width increases, the laser intensity will increase; as the pulse width increases, the average laser power increases and the slit width increases; In general, the slit width widens as the pulse frequency increases. The slit width will decrease when the frequency exceeds a certain value.
Effect of cutting speed
Laser Cutting Machine, cutting speed has a significant effect on the quality of the material being cut. The ideal cutting speed ensures that the cutting surface provides a relatively stable line and no dross under the material. When the auxiliary gas pressure and laser power are fixed, there is a non-linear inverse relationship between cutting speed and slot width. When the cutting speed is relatively slow, the effect time of the laser energy in the slit will be prolonged, resulting in an increase in the width of the slit. When the speed is too slow, the impact time of the laser beam is too long, the upper slit and the lower slit of the workpiece are greatly different, the cutting quality is reduced, and the production efficiency is greatly reduced. As the cutting speed increases, the effect time of the laser energy on the workpiece becomes shorter, the heat dissipation effect and the heat conduction effect decrease, and accordingly the slit width decreases. When the cutting speed is too high due to insufficient cutting heat, the workpiece material to be cut will not be affected. This phenomenon belongs to incomplete cutting, and the molten material cannot be blown out in time. These molten materials will re-weld the cut seams.
Effect of focus position
Laser Cutting Machine, Focus position is the distance that the laser focuses on the surface of the workpiece, which directly affects the surface roughness of the workpiece, the slope and width of the slit, and the adhesion of the slag. If the focus position is too high, it will increase the heat absorbed by the lower end of the workpiece being cut. When the cutting speed and auxiliary air pressure are fixed, the cutting material and the material close to the cutting source will flow in the form of liquid on the lower surface. After cooling, the molten material will stick to the bottom surface of the workpiece like a ball; If the position is delayed, it reduces the heat absorbed by the lower surface of the material being cut, so that the material in the cut seam is not completely melted, and some sharp and short residues will stick to the lower surface of the sheet. Generally, the focus position should be on the surface of the workpiece or slightly below, but different materials have different requirements. When cutting carbon steel, when the focus is on the surface of the steel plate, the cut quality is better; When cutting stainless steel, when the focus is about 1/2 of the thickness of the steel plate, the effect is better.
Advantages of CNC Laser Cutting Machine
1. Laser cutting technology belongs to contactless processing. The surface of the workpiece is irradiated with a high-intensity laser beam to achieve melting. The high-pressure gas blows the slag and completes the cutting process. The whole process belongs to CNC machining, without contact and deformation.
2. Laser Cutting Machine is not limited by the complexity of the graphics. The processing speed is fast, the precision is high, and the cutting section is beautiful. It can transform the original cooling metal materials into artistic patterns. Under the influence of light, the metal pattern is more refined and high-end.
3. Aesthetically, the laser beam of the laser cutting machine is concentrated in a small area. Because of the energy concentration, only a small amount of heat is transferred to other parts of the steel, resulting in little or no deformation. Therefore, the machining accuracy is high, the cross section is smooth, and there is no stress deformation. The machined stainless steel sheet has a high "color value".