How fiber laser cutting machine works？

One of the most common ways to use fiber laser cutting machines is to cut metal plates. The fiber laser cutting machine can process various metal materials, including stainless steel, carbon steel, alloy steel, aluminum, galvanized sheet, copper, silver, gold, etc. For these materials, you can choose different fiber laser sources. On mild steel, stainless steel and aluminum plates, the laser cutting process is very precise, the cutting quality is excellent, the cut width is very small, the heat affected zone is small, and very complex shapes and small holes can be cut. Laser cutting machines can also be used for laser engraving.

We will understand the working mode of fiber laser cutting machine through the following points.

What is laser beam

The laser beam is a series of very high intensity light with a single wavelength or color. For a typical CO2 laser, this wavelength is in the infrared part of the spectrum, so it is invisible to the human eye. When the beam travels from the laser resonator, the beam diameter is only about 3/4 inch of the beam path of the machine. It may bounce in different directions through multiple mirrors or "beam benders" before it is finally focused on the board. The focused laser beam passes through the nozzle hole before hitting the plate. Also flowing through the nozzle hole is compressed gas, such as oxygen or nitrogen.

What is the essence of laser

The laser essentially melts the material of the part to be cut, so it is more like melting than cutting. The high power density causes the material to quickly heat up, melt, and partially or completely vaporize. This means it can easily cut hard metals and gems like cloth.

What is the working principle

The working principle is to make a focused and precise laser beam pass through the material you want to cut to provide an accurate and smooth finish.

The fiber laser source can output a high-power laser beam focused on the surface of the material, so that the focused area instantly evaporates or melts. Under the control of numerical value and mechanical system, the laser head moves and changes the laser spot accordingly, thus realizing fast, high-precision automatic cutting.

Focusing the laser beam can be done through a special lens or curved mirror, which is performed in the laser cutting head. The beam must be precisely focused so that the shape of the focus point and the energy density of the point are completely circular and consistent, and are located in the center of the nozzle. By focusing the large beam to a single precise point, the heat density at that point is extremely high. Consider using a magnifying glass to focus the sun's rays on the leaves and how to start a fire. Now consider concentrating 6 kilowatts of energy into one point, and you can imagine how hot that point will become.

On the CNC cutting machine, the laser cutting head moves on the metal plate in the shape of the required part to cut the part from the metal plate. The capacitive height control system maintains a very precise distance between the end of the nozzle and the plate being cut. This distance is important because it determines the position of the focal point relative to the surface of the plate. The cutting quality can be affected by raising or lowering the focus from directly above, directly above, or directly below the board.

Why use fiber laser cutting machine

Fiber lasers have a higher energy conversion rate, saving operation and maintenance costs.

The quality of the beam delivered by the fiber laser is very high. Since the beam is still contained in the core of the fiber, it maintains a straight beam that can be super-focused. The spot of the fiber laser beam can be made very small, which is very suitable for applications such as laser cutting.

The fiber laser produces the smallest kerf and hot area to maintain cutting stability and avoid material deformation.

While maintaining high quality, so does the power delivered by the fiber laser beam. Has an incredibly high level of power output. Traditional laser machines take a lot of time to start and adjust the machine, and fiber lasers don't have to.

Another useful aspect of the way fiber lasers work is that despite their high intensity and high power output, they are very easy to cool while maintaining high efficiency.

The laser cutting machine adopts semiconductor modular and redundant design, and there is no optical lens in the resonant cavity.  The fiber laser head is equipped with a protective lens to protect the focusing lens and reduce parts consumption. The laser head will not directly touch the material, so as not to scratch the material and ensure high-quality cutting results.

The fiber laser cutting machine works in a safe and environmentally friendly way. There is almost no pollution and noise, and the workshop environment can be well protected.