How does a fiber laser cutting machine work?

A fiber laser cutting machine works by using a high power fiber laser to melt or vaporise material along a predetermined cutting path. Its general operation is as follows:

1. Laser beam generation: The process starts with the generation of a high-intensity laser beam inside a fiber laser resonator. The resonator consists of a fiber optic cable doped with rare earth elements such as erbium, ytterbium or neodymium. These elements enable the fibre to amplify light and produce a powerful laser beam.

2. Beam Delivery System: The laser beam passes through a series of mirrors and lenses that direct and focus the beam to a small, precise point on the surface of the material. The focusing lens ensures that the laser beam is concentrated and strong enough to cut the material effectively.

3. Material Interaction: When the focused laser beam hits the material surface, it rapidly heats up and melts or vaporises the material along the cutting path. The intense heat causes the material to reach its melting or vapourisation point, which creates a narrow kerf or passes through the material. 

4. Auxiliary Gas: In many fiber laser cutting machines, a high pressure auxiliary gas (e.g. oxygen, nitrogen or air) is often used to blow away the melted or vaporised material in the cutting area. This gas stream helps prevent debris build-up and ensures a clean, precise cut.

5. CNC Control: The entire cutting process is controlled by a Computer Numerical Control (CNC) system that precisely coordinates the movement of the laser head and the positioning of the material. The CNC system follows a pre-programmed cutting path based on the design specifications provided by the CAD/CAM software.

6. Cooling System: Fiber laser cutting machines are also equipped with a cooling system to dissipate the heat generated during the laser generation process and to maintain optimum operating conditions for the laser source and other components.

7. Safety measures: Fiber laser cutting machines usually include safety features such as guards, laser safety glasses and interlock systems to ensure the safety of the operator and bystanders during operation.

Overall, fiber laser cutting machines offer high precision, speed and versatility in cutting a wide range of materials such as metals, plastics and composites, making them indispensable tools for modern manufacturing and fabrication industries.