EN
In the rapidly changing science and technology, the manufacturing industry is experiencing profound changes, fiber laser cutting technology as one of the key forces, has become an indispensable means of processing in many production areas.
Understanding the cutting thickness of the relevant knowledge, for optimizing the production process, improve product quality and cost control is of great significance.
Fiber laser cutting technology by virtue of its unique advantages, in the manufacturing industry quickly came to prominence. It can realize high – precision, high – speed cutting, narrow cutting slit, small heat – affected zone, greatly improving the material utilization rate.
For example, in the manufacture of electronic equipment, fine cutting of tiny parts to meet the demand for precision production; in the field of automobile manufacturing, it can quickly cut complex shapes of body parts, significantly improving production efficiency.
Cutting thickness is directly related to all aspects of production. If the cutting thickness exceeds the capacity of the equipment, the cutting speed will be greatly reduced and the production progress will be hindered. From the cost point of view, inappropriate cutting thickness may lead to material waste, equipment loss increase, and thus increase production costs.
Moreover, the cutting thickness has a significant impact on product quality, and the appropriate cutting thickness can ensure that the cutting surface is flat and smooth, reduce the thermal impact on the material properties of the damage to ensure that the mechanical properties of the product and the appearance of quality.
The principle of fiber laser cutting is to use high energy density laser beam to irradiate the material surface. After the laser energy is absorbed by the material, the material is rapidly heated up to the melting point or even boiling point, and the material is melted or vaporized.
At the same time, the melted or vaporized material is blown away from the cutting area by an auxiliary gas, thus forming a continuous cutting seam and realizing the separation of the material. Different materials have different absorption properties of the laser, which determines the direction of adjustment of the laser parameters during the cutting process.
| Material | 500W Cutting thickness (mm) | 1000W Cutting thickness (mm) | 2000W Cutting thickness (mm) |
| Carbon steel | approx. 6 | 10 | 20 |
| Stainless steel | approx. 3 | 5 | 8 |
Laser power and cutting thickness is obviously positively correlated. To cut 10mm thick carbon steel, for example, 1000W fiber laser cutting machine cutting speed is slow, and may require multiple cuts to complete, the cutting surface quality is also poor; and the use of 2000W equipment, the cutting speed can be greatly increased, the cutting surface is smoother, the heat affected zone is also smaller.
High – strength, high – hardness materials, such as certain alloy steel, its inter – atomic bonding, cutting requires more energy to break the chemical bond, which puts forward higher requirements for laser power. For example, cutting high hardness mold steel, compared with ordinary carbon steel, requires higher power laser equipment and finer parameter adjustment.
Materials with high thermal conductivity, such as copper, lose heat rapidly during the cutting process, making it difficult to maintain high temperatures in the cutting area, increasing the difficulty of cutting and usually requiring higher power lasers to compensate for heat loss. Materials with high reflectivity, like aluminum, will reflect a large amount of laser energy back, reducing the utilization rate of the laser, making cutting difficult, often requiring special optical treatment or adjustment of laser parameters to improve the cutting effect.
Cutting speed is closely related to cutting thickness and quality. Too fast, the laser action time is short, the material can not be fully melted or vaporized, there will be incomplete cutting, cutting surface roughness and other issues; too slow, although the cutting quality can be guaranteed, but the production efficiency is low, and the heat – affected zone will be expanded.
| Auxiliary gas | Applicable materials | Function |
| Oxygen | Carbon steel | Oxidizing reaction with iron, releasing extra heat, improving cutting speed and efficiency. |
| Nitrogen | Stainless steel, aluminum | Prevents oxidation of the material and ensures the smoothness of the cutting surface. |
Focusing and lens quality: focusing accuracy and lens quality directly affect the distribution of laser energy on the material surface. High – quality lenses can focus the laser beam into a very small spot, increase the energy density and enhance the cutting ability.
The role of nozzle diameter: Nozzle diameter has a large impact on the cutting process. Smaller nozzle diameter can make the laser beam more concentrated, suitable for cutting thin materials, and can obtain higher precision and quality; while cutting thick materials, larger nozzle diameter is convenient to provide sufficient auxiliary gas flow, effectively discharging the melted and vaporized material, and maintaining the stability of the cutting process.
| Carbon steel thickness (mm) | Applicable laser power | Cutting speed (mm/s) | Auxiliary gas and pressure (MPa) |
| <5 | 500W – 1000W | 20 – 50 | Oxygen, 0.6 – 0.8 |
| 10 – 20 | 2000W – 3000W | 10 – 30 | Oxygen, 0.8 – 1.2 |
| Stainless steel thickness (mm) | Applicable laser power | Cutting speed (mm/s) | Auxiliary gas |
| <3 | 500W – 1000W | Approx. 80 | Nitrogen |
| 10 – 15 | 3000W – 5000W | 20 – 40 | Nitrogen |
| Aluminum and aluminum alloys Thickness (mm) | Applicable laser power | Cutting speed (mm/s) | Auxiliary gas | Special requirements | Handling of thick materials |
| <5 | 1000W – 2000W | 30 – 60 | Nitrogen | Laser polarization perpendicular to the material surface | Above 4000W is recommended in combination with pre – heating |
| >10 | >4000W | – | – | – | – |
| Thickness of copper and copper alloys (mm) | Applicable laser power | Cutting speed (mm/s) | Auxiliary gas | Special processes |
| <3 | 1000W – 1500W | 20 – 40 | Oxygen | – |
| 5 – 10 | 3000W – 4000W | – | – | Using pulse cutting mode |
| Plastic thickness (mm) | Applicable laser power | Cutting speed (mm/s) | Auxiliary gas | Adjustment for cutting thick materials |
| 1 – 3 | 500W – 800W | 50 – 100 | Compressed air | Reduce the cutting speed and increase the laser pulse frequency. |
| 3 – 10 | – | – | – | – |
| Thickness of composite material (mm) | Applicable laser power | Cutting speed (mm/s) | Auxiliary gas | Points for material properties |
| 5 – 10 (carbon fiber reinforced) | 1000W – 2000W | 10 – 30 | Nitrogen | Anisotropic, flexible adjustment of parameters is required |
The cutting thickness can be estimated by the formula, such as (T is the maximum cutting thickness, unit mm; P is the laser power, unit kW; k and n are constants related to the material and equipment).
For example, for a certain stainless steel material, it has been experimentally determined that,, if a 4kW laser is used, the formula will yield mm. In practice, it needs to be adjusted in conjunction with the specific cutting conditions.
Optimization of the machine parameters: Optimization of the machine parameters is essential to improve cutting thickness and quality. When adjusting the laser power, it should be reasonably selected according to the thickness and characteristics of the material, and dynamically adjusted during the cutting process.
For example, when cutting materials with increasing thickness, gradually increase the laser power to ensure the continuity and stability of cutting. Optimization of focusing parameters should not be ignored, precise adjustment of lens focal length and position, so that the laser beam on the material surface to form the best spot and energy distribution.
Process optimization: Process optimization includes the reasonable use of auxiliary gas and fine adjustment of cutting speed. The auxiliary gas should be selected according to the material type and cutting requirements, while controlling the pressure and flow rate to ensure effective removal of slag and protection of the cutting surface. Cutting speed adjustment needs to take into account the material thickness, laser power and equipment performance and other factors, in order to achieve the best cutting results.
When cutting thick materials, it is common that the heat-affected zone is enlarged and the cutting quality is reduced. Take cutting 30mm thick carbon steel as an example, the heat-affected zone can be reduced by lowering the laser power (e.g. from 5000W to 4000W), slowing down the cutting speed (e.g. from 10mm/s to 5mm/s), increasing the auxiliary gas flow rate and pressure, and real-time cooling of the cutting area with the cooling system to reduce the heat-affected zone, and improve the flatness and roughness of the cutting surface.
The difficulty of thin material cutting lies in ensuring accuracy and preventing deformation. When cutting 0.5mm thick stainless steel foil, the laser power can be reduced to about 300W, the cutting speed can be increased to about 150mm/s, and a smaller diameter nozzle and high quality focusing lens can be used to improve the cutting accuracy and ensure the cutting edge is smooth and vertical.
For highly reflective materials such as aluminum and copper, antireflective coatings can be applied to the laser lens, e.g. multi – layer dielectric antireflective coatings, which reduce the laser reflection on the surface of the material by 30% – 50%. At the same time, optimize the laser wavelength and polarization direction to enhance the optical match with the material and improve the cutting effect.
For materials with uneven thickness, sensors can be used to detect thickness changes in real time, such as high – precision laser displacement sensors. When the material thickness is detected to increase, the control system automatically increases the laser power and reduces the cutting speed to ensure the consistency of the cutting quality.
When cutting stainless steel, for example, with 3kW power, the fiber laser cutting machine can cut the maximum thickness of about 10mm, while the CO₂ laser cutting machine can usually only reach about 6mm. When cutting 15mm thick carbon steel, the cutting speed of fiber laser cutting machine is 20% – 30% faster than that of CO₂ laser cutting machine, and the roughness of the cutting surface is lower, with smaller heat-affected zone. When cutting aluminum and aluminum alloy, the maximum cutting thickness of fiber laser can reach 15mm, while the CO₂ laser, due to the high reflectivity of aluminum, is generally limited to a cutting thickness of less than 10mm, and the cutting efficiency and quality of the cutting surface is poor.
When cutting stainless steel, under 3kW power, fiber laser cutting machine can cut 10mm thick material, Nd laser cutting machine can only reach about 8mm. When cutting carbon steel, although the Nd laser can achieve a certain thickness of cutting, but in terms of cutting speed, cutting surface quality and other aspects, compared with the fiber laser there is a gap.
Consider the Range of Material Thickness
Ensure that the selected equipment can handle the required thickness of the material to be cut, and fully understand the maximum and minimum cutting thickness capabilities of different models of fiber laser cutting machines to match the actual production requirements.
Select compatible equipment according to the characteristics of the cutting material. Different materials have different characteristics of laser absorption and reflection, so it is necessary to select a fiber laser cutting machine that can adapt to its characteristics.
According to the production scale and speed requirements, select the appropriate equipment. If the production volume is large, you need to choose high – power, high – speed fiber laser cutting machine, in order to protect the production efficiency.
Within the budget, comprehensively consider the price and performance of the equipment, choose cost – effective fiber laser cutting machine, to achieve the best balance between budget and performance.
Select manufacturers that can provide reliable after – sales support to ensure that the equipment in the use of the process of problems, can get timely maintenance and technical support to reduce downtime.
In conclusion, fiber laser cutting thickness is influenced by multiple factors. Understanding principles, optimizing parameters, and choosing suitable machines are crucial for efficient and high – quality production.
