With the wide application of laser cutting machines in various industries, many people do not know how to choose the very professional performance parameters when purchasing laser cutting machines. Now, Tianchen Laser will share with you the interpretation of the performance parameters of laser cutting machines.

1. Effect of auxiliary air pressure

In laser cutting, auxiliary air pressure can blow off the slag and cool the heat affected zone. Auxiliary gas includes oxygen, compressed air, nitrogen and inert gas. For some metal materials, inert gas or compressed air is generally used to prevent material burning. Such as cutting of aluminum alloy materials. Active gas (such as oxygen) is used for most metal materials, because oxygen can oxidize metal surface and improve cutting efficiency. When the auxiliary air pressure is too high, eddy current appears on the material surface, which weakens the ability to remove molten materials, leading to wider slits and rough cutting surfaces; When the air pressure is too low, the melt cannot be completely blown away, and the lower surface of the material will stick with slag. Therefore, the auxiliary gas pressure shall be adjusted during cutting to obtain the best cutting quality.

2. Influence of laser power

The size of laser power has a considerable impact on cutting speed, kerf width, cutting thickness and cutting quality. The power required depends on the characteristics of the material and the cutting mechanism. For example, materials with good thermal conductivity, high melting point and high reflectivity of the cutting surface require higher laser power. Generally, under certain other conditions, there is a laser power that can obtain the best cutting quality in laser cutting. Further reduction or increase of the power will result in slag hanging or overburning, which will lead to the decline of processing quality. In addition, with the increase of the discharge voltage, the laser intensity will increase due to the increase of the input peak power, so that the diameter of the spot will increase and the width of the slit will increase accordingly; With the increase of the pulse width, the average power of the laser will increase, and the width of the laser kerf will increase; Generally, with the increase of pulse frequency, the slit will also become wider. When the frequency exceeds a certain value, the slit width will decrease.

3. Effect of cutting speed

In laser cutting, the cutting speed has a considerable impact on the quality of the cutting materials. The ideal cutting speed will make the cutting surface appear more stable lines, and there will be no slag at the lower part of the materials. When the auxiliary gas pressure and laser power are fixed, the cutting speed and the kerf width show a nonlinear inverse relationship. When the cutting speed is relatively slow, the action time of laser energy in the kerf is prolonged, which leads to the increase of the kerf width. When the speed is too slow, the action time of the laser beam is too long, the difference between the upper kerf and the lower kerf of the workpiece will be large, the cutting quality will decline, and the production efficiency will also be greatly reduced. With the increase of cutting speed, the action time of the laser beam energy on the workpiece becomes shorter, which makes the thermal diffusion and heat conduction effects smaller, and the width of the kerf correspondingly smaller. When the speed is too fast, the workpiece material to be cut will not cut through due to insufficient cutting heat input. This phenomenon belongs to incomplete cutting, and the melted material cannot be blown off in time. These melts will cause the cutting seam to be re welded.

4. Effect of focus position

The focus position is the distance between the laser focus and the workpiece surface, which directly affects the section roughness, the slope and width of the kerf, and the adhesion of the molten residue. If the focus position is too advanced, the heat absorbed by the lower end of the workpiece to be cut will increase. When the cutting speed and auxiliary air pressure are fixed, the material to be cut and the melted material near the cutting seam will flow as liquid on the lower surface. After cooling, the melted material will adhere to the lower surface of the workpiece as a ball; If the position lags behind, the heat absorbed by the lower end face of the material to be cut will be reduced, so that the material in the cutting seam cannot be completely melted, and some sharp and short residues will be stuck on the lower surface of the plate. Generally, the focus position should be on the workpiece surface or slightly lower, but different materials have different requirements. When cutting carbon steel, the cutting quality is good when the focus is on the plate surface; When cutting stainless steel, the effect is better when the focus is about 1/2 of the plate thickness.

The above is what Xiaobian shared with you about the performance parameters of the laser cutting machine.