Causes of edge burning and slag hanging during laser cutting sheet metal parts: a large amount of heat will be generated during laser cutting sheet metal parts. Under normal circumstances, the heat generated by cutting will be diffused to the processed sheet metal along the cutting seam for sufficient cooling.
During the processing of small holes by metal laser cutting machine, the outside of the holes can be fully cooled. However, the small holes inside the single hole have small space for heat diffusion, and the heat energy is too concentrated to cause over burning and slag hanging. In addition, in thick plate cutting, the molten metal accumulated on the surface of the material during piercing and the heat accumulation will cause the auxiliary air flow to be disordered and the heat input to be excessive, thus causing over burning.
Solution to over burning during laser cutting carbon steel keyhole cutting: in carbon steel cutting with oxygen as auxiliary gas, the key to solve the problem is how to suppress the generation of oxidation reaction heat. The method of auxiliary oxygen during piercing and lag switching to auxiliary air or nitrogen for cutting can be adopted. This method can process small holes of 1 / 6 thick plate.
Pulse cutting conditions with low frequency and high peak output power can reduce heat output, which is helpful to optimize cutting conditions. Setting the conditions as single pulse laser beam, high peak output with high energy intensity and low frequency can effectively reduce the accumulation of molten metal on the material surface during the piercing process and effectively suppress the heat output.
Solution for laser cutting of aluminum alloy and stainless steel: in the processing of such materials, the auxiliary gas is nitrogen, and edge burning will not occur in the cutting. However, due to the high temperature of the material inside the small hole, the slag hanging phenomenon inside the small hole will be more frequent.
The effective solution is to increase the pressure of auxiliary gas and set the conditions as high peak output and low frequency pulse conditions. When the auxiliary gas is used with air, it will not be burnt, but it is easy to have slag hanging at the bottom. It is necessary to set the conditions to high auxiliary gas pressure, high peak output and low frequency pulse conditions.