Fiber laser is a solid-state laser, which is developing rapidly in the metal cutting industry. Unlike CO2, optical fiber technology uses solid gain media, not gas or liquid. The "seed laser" generates a laser beam, which is then amplified inside the glass fiber. The wavelength of the fiber laser is only 1.064 nm, and the spot size produced is very small (100 times smaller than CO), which is very suitable for cutting reflective metal materials. Compared with CO, this is one of the main advantages of Fiber 2.

Advantages of fiber laser cutting machine include:

1. Fast processing time.

2. Lower energy consumption and bills – due to higher efficiency.

3. Higher reliability and performance - no optics required to adjust or align, no bulb replacement required.

4. Minimal maintenance.

5. Higher productivity - lower operating costs can bring you greater return on investment.

There are many ways to use laser cutting machines, among which different types are used to cut different materials. Some of these methods are vaporization, melt blowing, melt blowing and combustion, thermal stress cracking, scribing, cold cutting and laser cutting with stable combustion.

Vaporization cutting

In vaporization cutting, the focused beam heats the material surface to the flash point, and generates a keyhole. The keyhole will cause a sudden increase in the absorption rate, which will make the hole deeper. With the deepening of the hole and the boiling of the material, the steam generated eroded the molten wall, ejected the molten material and further expanded the size of the hole. This method is usually used to cut non molten materials such as wood, carbon and thermosetting plastics.

Melting and striking

Melt blowing or melt cutting uses high pressure gas to blow out molten materials from the cutting area, thus greatly reducing the power demand. First, the material is heated to the melting point, and then the molten material is blown out of the slit with a gas jet, thus avoiding the need to further increase the material temperature. The material cut in this way is usually metal.

Thermal stress cracking

Brittle materials are particularly sensitive to thermal fracture, which is a function used in thermal stress cracking. The beam is focused on the surface, causing local heating and thermal expansion. This leads to cracks, which can then be guided by moving the beam. The cracks can move in m/s order. Usually used to cut glass.

Reaction cutting

It is also called "laser cutting with stable combustion" and "flame cutting". Reactive cutting is like oxygen cutting torch, but laser beam is used as ignition source. It is usually used to cut carbon steel with a thickness of more than 1 mm. This process can be used to cut very thick steel plates with relatively low laser power.

Industrial laser cutting machines usually have three different configurations: mobile materials, hybrid power and flight optical systems. These refer to the way the laser beam moves on the material to be cut or processed. For all of these, the motion axes are usually specified as the X and Y axes. If you can control the cutting head, specify it as the Z axis.

The moving material laser has a fixed cutting head under which the material is moved. This method provides a constant distance from the laser generator to the workpiece and a single point from which to remove the cutting waste liquid. It requires fewer optical elements, but requires moving the workpiece. This type of machine often has the least light beam transmission optics, but it is also often the slowest.

The hybrid laser provides a table that moves along one axis (usually the X axis) and the head along the shorter (Y) axis. This results in a more constant beam propagation path length than flight optical machines, and can allow simpler beam propagation systems. This reduces the power loss in the transmission system and increases the capacity per watt compared to flight optical machines.

The flight optical laser has a fixed table and a cutting head (with a laser beam), and the cutting head moves on the workpiece in both horizontal directions. The flying optical tool can keep the workpiece stationary during processing, and usually does not require material clamping. The motion mass is constant, so the dynamics is not affected by the change of workpiece size. The flying optical machine is the fastest model, which is very beneficial for cutting thinner workpieces.

The flight optical machine must use some method to consider the change of beam length from near field (near resonator) cutting to far field (far resonator) cutting. Common methods of controlling this include collimation, adaptive optics, or using a constant beam length axis.

Five axis and six axis machine tools also allow cutting of shaped workpieces. In addition, there are many ways to orient the laser beam to the formed workpiece, maintain proper focusing distance and nozzle spacing.

pulsation

In some laser cutting processes, especially when perforating or requiring very small holes or very low cutting speed, pulse lasers that provide high-energy pulses in a short period of time are very effective, because if a constant laser beam is used, the heat may melt the entire cut part.

Most industrial lasers have the ability to pulse or cut CW (continuous wave) under the control of CNC (numerical control) program.

Double pulse laser uses a series of pulse pairs to improve material removal rate and hole quality. Essentially, the first pulse removes the material from the surface, and the second pulse prevents the ejector from adhering to the side of the hole or notch. [18]

Energy consumption

The main disadvantage of laser cutting is high power consumption. Industrial laser efficiency may be between 5% and 45%. [19] The power consumption and efficiency of any particular laser will depend on the output power and operating parameters. This will depend on the type of laser and how well the laser matches the workpiece at hand. The laser cutting capability required for a particular job (called heat input) depends on the type of material, thickness, process used (reactivity/inertness), and the desired cutting rate.