Four tricks | ways to solve the overburning caused by laser cutting

What is overburn?

The metal laser cutting machine generates a lot of heat when processing the sheet metal. Under normal circumstances, the heat generated by the cutting will spread along the slit to the processed sheet metal to be fully cooled. In the processing of small holes in the metal laser cutting machine, the outside of the hole can be sufficiently cooled, but the small hole inside the single hole is likely to cause overburning, slagging, etc. because of the small space for heat diffusion and excessive heat energy. In addition, in the cutting of thick plates, the molten metal accumulated on the surface of the material and the heat accumulation generated during the piercing will cause the auxiliary airflow to be turbulent, and the heat input will be too much, which will cause overburn.

How to avoid overburn when laser cutting sheet metal?

【1】Add cooling point at the corner
When cutting sharp-corner metal plates, the location where overburning is more likely to occur is often at the sharp corners. Overburning will cut the sharp corners into a circle. At this time, add a cooling point at the sharp corners and stop at the sharp corners. Click, blow.

【2】Using high-power laser
When cutting carbon steel, a higher power laser can be used, and a bright surface cutting process can be used to effectively avoid over-burning, and this cutting process can cut finished products with no burrs and bright cut surfaces.

【3】Using nitrogen cutting
In sheet metal cutting with oxygen as the auxiliary gas, nitrogen can be used for cutting. When cutting with nitrogen, the material is completely melted by laser energy, and the nitrogen is blown out of the cutting seam to avoid inappropriate chemical reactions. The temperature in the melting point area is relatively low, coupled with the cooling and protection of nitrogen, the response is stable and uniform, and the cutting quality is high. The section is fine and smooth, the surface roughness is low, and there is no oxide layer.

【4】Increase the air pressure
When the fiber laser cutting machine is used to process aluminum alloy and stainless steel, the auxiliary gas used is nitrogen or air. There will be no burnt edges during the cutting process. However, due to the high temperature of the material inside the small hole, the slagging phenomenon on the inside will be reduced. More frequently. In this case, burrs and dross can be reduced by increasing the pressure of the auxiliary gas.