What are the important parameters of the laser cutting machine

How is the laser cutting effect affected by the auxiliary air pressure, laser power, cutting speed, focus position and other parameters?

The influence of auxiliary air pressure

In the laser cutting process, the auxiliary air pressure plays a role in blowing away slag, cooling material, and auxiliary combustion. Auxiliary gases include oxygen, compressed air, nitrogen, and inert gases.

Oxygen can participate in metal combustion, which can improve cutting efficiency and is suitable for cutting most metals; inert gas and air are suitable for cutting some metal materials (such as aluminum alloy) and non-metal materials, which can prevent materials from burning .

If the auxiliary gas pressure is too high, a vortex will appear on the surface of the material, which will weaken the ability to remove the molten material, resulting in wider slits and rough cutting surfaces; if the pressure is too low, the molten material cannot be completely blown away , The bottom surface of the material will adhere to the slag. Therefore, the auxiliary gas pressure should be adjusted during cutting to obtain the best cutting quality.

The influence of laser power

Laser power has a great influence on cutting speed, slit width, cutting thickness and cutting quality. The power depends on the material characteristics and cutting mechanism. For example, materials with high melting points (such as alloys) and high reflectivity of the cut surface (such as copper and aluminum) require larger laser power.

There is a laser power in the laser cutting process to obtain the best cutting quality. Below this laser power, imperviousness or slagging may occur; above this power, it will overburn .

The influence of cutting speed

The ideal cutting speed will make the cutting surface show a relatively stable line, the material section is smooth, and there is no burr. When the auxiliary gas pressure and laser power are constant, the cutting speed and the slit width show a non-linear inverse relationship. When the cutting speed is relatively slow, the action time of the laser energy in the slit is prolonged, resulting in an increase in the slit width , Or the underside of the cutting seam is too wide, the cutting quality and production efficiency will be greatly reduced.

Accelerate the cutting speed, and the action time of the laser beam energy on the workpiece becomes shorter, so that the effect of heat diffusion and heat conduction becomes smaller, and the width of the slit becomes correspondingly smaller. But when the speed is too fast, the workpiece material to be cut will become impenetrable due to insufficient cutting heat input.

The influence of focus position

The focus position is the distance from the laser focus to the surface of the workpiece, which directly affects the roughness of the cut surface, the slope and width of the slit And the adhesion status of the molten residue. If the focus position is too advanced, this will increase the amount of heat absorbed by the lower end of the workpiece to be cut. When the cutting speed and auxiliary air pressure are constant, the material being cut and the melted material near the slit will flow in liquid form on the lower surface. After cooling, the melted material will adhere to the lower surface of the workpiece in a spherical shape; if the position is lagging, the heat that can be absorbed by the lower end of the cut material is reduced, so that the material in the slit can not be completely melted, and under the plate Some sharp and short residues will adhere to the surface. Normally, the focus position should be on the surface of the workpiece or slightly lower, but different material requirements are different. When cutting carbon steel, the cutting quality is better when the focus is on the surface of the plate; while for stainless steel cutting, the focus should be within the thickness of the plate. The effect is better when it is about 1/2.