Numerical control laser cutting machine is more and more widely used in metal processing industry. Today, Jinan rebound CNC machine company (a manufacturer mainly producing CNC fiber laser cutting machine and CNC plasma cutting machine) introduces four common laser cutting methods.

Melt cutting

In laser melting cutting, after the workpiece is locally melted, the molten material is sprayed out with the help of air flow. Because the transfer of material only occurs in its liquid state, this process is called laser melting cutting. During laser melting cutting, of course, the material is heated to a certain temperature to melt, and then the non oxidizing gas is injected through the nozzle coaxial with the beam, and the pressure of the gas is used to discharge the liquid metal to form a notch. The energy required for laser melting cutting is only 1 / 10 of that of vaporization cutting, and there is no need to vaporize the metal completely. Laser melting cutting can obtain oxidation-free cuts for iron materials and titanium metals. The laser power density that produces melting but not gasification is between 104w / cm2 and 105 w / cm2 for steel materials.

Vaporization cutting

In the process of laser vaporization cutting, the high-energy and high-density laser beam is used to heat the workpiece, raise the temperature, and vaporize the material into steam in a very short time. When these steam is ejected, a notch will be formed on the material, so as to achieve the cutting effect. However, the heat of vaporization of general materials is very large, so the speed of the material surface temperature rising to the boiling point temperature is so fast that it is enough to avoid melting caused by heat conduction. Therefore, some materials vaporize into steam and disappear, and some materials are blown away from the bottom of the slit as ejecta by the auxiliary gas flow. In this case, very high laser power is required. In order to prevent the material vapor from condensing on the slit wall, the thickness of the material must not greatly exceed the diameter of the laser beam. This process is therefore only suitable for applications where the exclusion of molten material must be avoided. The materials used in laser vaporization cutting generally include very thin metal materials and non-metallic materials. When the plate thickness is certain, the maximum cutting speed is inversely proportional to the gasification temperature of the material. The required laser power density is greater than 108W / cm2 and depends on the material, cutting depth and beam focus position. When the plate thickness is certain, assuming sufficient laser power, the maximum cutting speed is limited by the gas jet speed.

Controlled fracture cutting

For brittle materials that are easy to be damaged by heat, high-speed and controllable cutting by laser beam heating is called controlled fracture cutting. The main content of this cutting process is: the laser beam heats a small area of brittle material, resulting in large thermal gradient and serious mechanical deformation, resulting in the formation of cracks in the material. As long as a uniform heating gradient is maintained, the laser beam can guide the crack in any desired direction. The material commonly used in this cutting is brittle material.

Oxidation melting cutting (laser flame cutting)

Melting cutting generally uses inert gas. If oxygen or other active gas is replaced, the material will be ignited under the irradiation of laser beam, and another heat source will be generated by fierce chemical reaction with oxygen to further heat the material, which is called oxidation melting cutting. Because of this effect, for structural steel with the same thickness, the cutting rate obtained by this method is higher than that by melting cutting. On the other hand, this method may have worse notch quality than melting cutting. In fact, it will produce wider slits, obvious 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 risk of burning sharp corners).

The above is about the introduction of four commonly used CNC laser cutting methods. If you or your friends need to purchase CNC plasma cutting machine and CNC fiber laser cutting machine, please do not hesitate to contact our company and look forward to your cooperation.