Laser cutting is one of the thermal cutting methods. The focused high power density laser beam is used to irradiate the workpiece, so that the irradiated material can be rapidly melted, vaporized, ablated or reach the ignition point. At the same time, the molten material can be blown off with the help of the high-speed air flow coaxial with the beam, so that the workpiece can be cut.

1、 Laser cutting applications

Most laser cutting machines are controlled by numerical control programs or made into cutting robots. As a precise processing method, laser cutting can cut almost all materials, including two-dimensional cutting or three-dimensional cutting of thin metal plates.

In the field of automobile manufacturing, the cutting technology of space curve such as car roof window has been widely used. Volkswagen of Germany uses a laser with a power of 500W to cut complicated body sheets and various curved parts. In the aerospace field, laser cutting technology is mainly used for cutting special aviation materials, such as titanium alloy, aluminum alloy, nickel alloy, chromium alloy, stainless steel, beryllium oxide, composite materials, plastics, ceramics and quartz. Aerospace parts and components processed by laser cutting include engine flame tube, titanium alloy thin-walled casing, aircraft frame, titanium alloy skin, wing stringer, tail wing wall panel, helicopter main rotor, and ceramic insulation tile of space shuttle.

Laser cutting forming technology is also widely used in the field of non-metallic materials. It can not only cut materials with high hardness and brittleness, such as silicon nitride, ceramics, quartz, etc; It can also cut and process flexible materials, such as cloth, paper, plastic plate, rubber, etc. If you use laser to cut clothes, you can save 10%~12% of clothing materials and increase the efficiency by more than 3 times.

2、 Laser cutting materials

1. Structural steel

When the material is cut with oxygen, good results will be obtained. When oxygen is used as the processing gas, the cutting edge will be slightly oxidized. For plates up to 4mm thick, nitrogen can be used as the processing gas for high-pressure cutting. In this case, the cut edge will not be oxidized. For plates with a thickness of more than 10 mm, a good effect can be obtained by using a special electrode plate for the laser and coating the workpiece surface with oil during processing.

2. Stainless steel

Oxygen can be used when the oxidation of the cutting face is acceptable; Nitrogen is used to obtain the edge without oxidation and burr, and no further treatment is required. Coating oil film on the surface of the plate will achieve better perforation effect without reducing the processing quality.

3. Aluminum

With high reflectivity and thermal conductivity, aluminum materials with thickness less than 6mm can be cut, depending on the alloy type and laser capacity. When cutting with oxygen, the cutting surface is rough and hard. When using nitrogen, the cutting surface shall be smooth. Pure aluminum is very difficult to cut because of its high purity. Only when a "reflection absorption" device is installed on the system can aluminum be cut. Otherwise, the reflection will destroy the optical components.

4. Titanium

Titanium plates are cut with argon and nitrogen as processing gas. Other parameters can refer to nickel chromium steel.

5. Copper and Brass

Both materials have high reflectivity and excellent thermal conductivity. Brass with thickness less than 1mm can be cut with nitrogen; Copper with thickness less than 2mm can be cut, and the processing gas must be oxygen. Copper and brass can only be cut when a "reflection absorption" device is installed on the system. Otherwise, the reflection will destroy the optical components.