1. Laser Power and Cutting Speed
Thin metal sheets (usually under 3 millimeters) require low laser power and a fast cutting speed. If the speed is too slow, it may cause burn marks or edge deformation.
Thicker sheets (above 6 millimeters) need higher power and slower speed. Cutting too quickly can result in incomplete cuts or rough, uneven edges.
Always match the laser power to the material thickness.
2. Focal Point Adjustment
For thin materials, the laser's focal point is usually placed right on or slightly above the surface. This gives clean and sharp edges.
For thicker plates, the focal point should be set a bit deeper into the material to help the beam cut through smoothly.
A wrong focal point position often leads to poor cutting quality.
3. Nozzle Size and Gas Pressure
Thin materials need a smaller nozzle and lower gas pressure. This helps avoid blowing away too much molten material, which could cause edge defects.
Thick materials require a larger nozzle and higher gas pressure to blow out the molten slag effectively and maintain a clean cutting surface.
For carbon steel, oxygen is usually used. For stainless steel or aluminum, nitrogen is preferred.
4. Piercing Time and Stability
Thin sheets can be pierced almost instantly, with little risk of damage.
Thick sheets need a longer, more stable piercing time. If rushed, it can cause craters or excessive heat marks at the piercing point.
Make sure the piercing process is smooth and controlled.
5. Heat Control and Material Deformation
Thin sheets are more sensitive to heat and may warp easily. It's important to keep the sheet flat, use proper clamping, and avoid leaving the laser on one spot too long.
Thick plates are less likely to deform due to their weight, but they may accumulate heat during long cuts. It helps to include brief pauses between sections to allow cooling.
6. Cut Quality Expectations
Cutting thin plates usually results in smooth edges and narrow kerf width, which is ideal for fine detail.
Cutting thick plates may leave some slag or rough edges depending on the settings and machine precision. Post-processing like grinding may be needed if appearance is important.
--Rayther Laser Lyra Zhang