The quality of fiber laser beams plays a crucial role in laser cutting and directly affects all aspects of the cutting effect. The quality of cutting not only determines the efficiency of production, but also affects the appearance and performance of the final product. The following are several key factors that affect the quality of fiber laser beam cutting:
1. Cut width and edge roughness
Cut width and edge roughness are important indicators of laser cutting quality. When the beam quality of fiber laser is high, the focus can be more concentrated, and the energy distribution in the cutting area can be more uniform, thereby achieving more precise cutting. High-quality laser beams can ensure narrower cuts, smoother edges, reduce the workload of post-processing, and improve the appearance quality of products. On the contrary, when the beam quality is poor, due to uneven focusing, the laser beam may experience energy scattering during the cutting process, resulting in an increase in the width of the cut, rough edges, and even charring or irregular cutting, which affects the overall quality of the product and increases the difficulty and cost of post-processing.
2. Heat-affected Zone (HAZ)
The heat-affected zone (HAZ) refers to the area where the material undergoes physical or chemical changes due to high temperatures during laser cutting. When the beam quality is high, the laser can release energy in the concentrated area of the focus, reducing the heat diffusion outside the focus and making the heat-affected zone relatively small. Thus, it can effectively control the thermal deformation and microstructure changes of the material during the cutting process, ensuring the accuracy and quality of the cutting area. When the beam quality is poor, the focusing ability of the laser beam decreases, and the heat energy diffuses more widely in the material, resulting in an expansion of the heat-affected zone. This may cause the material to overheat, melt, or even deform. It not only affects the cutting quality but may also damage the physical properties of the material, affecting subsequent processing or use.
3. Cutting speed and efficiency
Cutting speed and efficiency are one of the important indicators for evaluating the performance of laser cutting. A laser generator with good beam quality can provide high-density laser energy, enabling it to maintain high power output during the cutting process while avoiding excessive heat accumulation. This high-density energy can effectively cut materials at a relatively high cutting speed, thereby enhancing production efficiency. High-quality beams can also effectively enhance the precision of cutting, enabling both the cutting speed and quality to increase simultaneously. When the beam quality is poor, due to the problem of uneven focusing, the energy of the laser beam is unevenly distributed on the material. During the cutting process, excessive heat accumulation occurs, making it impossible to increase the cutting speed. The speed can only be reduced to avoid uneven cutting, thereby lowering the overall cutting efficiency.
4. Surface treatment
The surface finish after cutting is one of the important criteria for evaluating cutting quality. Higher beam quality can ensure uniform beam energy distribution during the cutting process, making the cutting surface smoother and reducing surface defects, cracks or charring. This not only enhances the appearance quality of the product but also reduces subsequent post-processing procedures such as slag removal, grinding, and polishing. On the other hand, low beam quality may lead to rough cutting surfaces, and even cause material charring and slag accumulation, increasing the difficulty and cost of post-processing. In severe cases, it can affect the performance and market competitiveness of the final product.
5. Material compatibility
Different types of materials have different requirements for laser cutting, and the quality of the fiber laser beam directly affects its adaptability to various materials. Laser generators with high beam quality can usually perform efficient cutting on a wider range of materials, especially on hard metals such as stainless steel and aluminum alloy. By optimizing the beam quality, higher precision and better cutting results can be guaranteed during the cutting process of these high-demand materials. For some soft materials, such as plastic or wood, the requirements for beam quality are relatively low. However, even so, the improvement of beam quality still helps to expand the material compatibility of the equipment, enabling it to handle a wider range of materials and enhance the diversity and flexibility of processing.
The beam quality of fiber lasers has a profound impact on many aspects of the laser cutting process, including cut width, edge roughness, heat-affected zone, cutting speed and efficiency, surface finish, and material compatibility, etc. Improving the quality of laser beams not only enhances cutting accuracy and reduces the heat-affected zone, but also optimizes cutting speed and surface quality, thereby increasing production efficiency and lowering post-processing costs. Optimizing beam quality is a key factor in enhancing the performance of laser cutting and is of great significance for improving the quality of the final product and the competitiveness of enterprises.