The process of laser cutting of metals
A wide range of materials such as wood, precious stones such as diamond, titanium, steel, reflective metals, glass, plastic, silicon, etc., of any thickness, can be laser cut, engraved on them, or made a hole This process does this by focusing the laser beam on the points where the cut should be made and provides a precise and smooth output by first creating holes with the laser beam at the cutting site, and then the beam in The length of the holes continues. The laser essentially melts the material it's passed through, so it's more like melting than cutting. The beams can be used in the form of pulses or continuous waves for laser cutting of metals. Each pulse applies the laser beam to the cutting site for a short period of time, while the wave laser does this continuously. Depending on the metal you are working with, you can control the beam intensity, length, and heat output, and you can also use a special mirror or lens to focus the laser beam more. Thanks to these facilities, the cutting process is controlled to the extent that 0.1 mm slits can be created with the help of laser cutting.
In the laser cutting of metals, a high-power laser beam is used, which is guided optically and with computer numerical control (CNC) towards the material. Typically, this process uses a motion control system to follow the CNC code of the pattern to be cut on the material. The laser beam used is created by exciting laser beams through electrical discharges or lamps inside a closed container. The rays are amplified by internal reflection through the mirror to create a stream of coherent monochromatic light. This light is focused on the work area by mirrors or optical fiber that directs the beam through a lens. In cases where it is necessary to start the cutting process from a point other than the edges of the metal sheet, the drilling process is used, due to which a high-power pulsed laser creates a hole in the material, for example, with 5 pulses of 5 seconds, a stainless steel sheet can be cut. He created a hole in the thick bell (13 mm).
Cut fusion:
During the fusion cutting process, an inert gas (usually nitrogen) is used to expel the molten material from the shell. Nitrogen gas does not react with the molten material and therefore does not contribute to the input energy.
Flame cut:
During the flame cutting process, oxygen is used as an auxiliary gas. In addition to exerting mechanical force on the molten material, oxygen creates an exothermic reaction that increases the energy input to the process.
Remote cut:
During the remote cutting process, materials are partially vaporized (melted) by a high-intensity laser beam and cut into thin sheets without auxiliary gas.
Removal of residues and cooling in the metal laser cutting process
In the process of laser cutting with the help of oxygen gas, the flow passes through a gas mixture. The type of gas flow is an influential factor in laser performance. Common types of oxygen laser include fast axial flow, slow axial flow, transverse flow and slab. Fast axial flow uses a mixture of carbon dioxide, helium and nitrogen at high speed by a turbine or blower. Cross-flow lasers use a simple blower to circulate the gas mixture at a slower rate, while slab or diffusion resonators use a static gas field that does not require pressure or glassware. Depending on the size and configuration of the system, different methods are used to cool the laser generator and external optics. The waste heat can be transferred directly to the air, but usually a refrigerant is used. Water is a commonly used coolant that is often circulated through a heat transfer system or chiller. An example of water-cooled laser processing is the laser microjet system, which couples a pulsed laser beam with a low-pressure water jet to direct the beam in the same way as an optical fiber. Water removes residues and cools the material. Fiber lasers have also become very popular for this purpose in the metal laser cutting industry. This technology uses a solid additive instead of liquid or gas. The laser is amplified in glass fibers to produce a much smaller beam than that obtained with oxygen techniques, which is well suited for cutting reflective metals.