The laser cutting process produces a lot of heat when the sheet metal part is processing, the heat is not diffused in time, and the burning edge phenomenon is caused. In the machining of metal laser cutting machine, the outside of the hole can be cooled, but the part of the small hole inside the single hole has less heat diffusible space, and the heat is too concentrated to cause overburning, slagging and so on. In addition, in the thick plate cutting, the molten metal accumulated on the material surface and the heat accumulation during the perforation will make the auxiliary airflow disordered, and the heat input will be excessive, which will lead the burning of the edge.
So how to solve the problem of burning and slagging?
Solution of overburning during laser cutting of small hole in carbon steel: In the carbon steel cutting with oxygen as the auxiliary gas, the key to solve the problem is how to suppress the generation of oxidation reaction heat. It can be cut by auxiliary oxygen during perforation and lagged switch to auxiliary air or nitrogen.
The pulse cutting condition with low frequency and high peak output power can reduce the heat output and optimize the cutting condition. Setting the condition as a single pulse laser beam, the high peak output of high energy intensity and the low frequency condition can reduce the accumulation of molten metal on the surface of the material during the perforation process and reduce the heat output.
The solution of Laser cutting of aluminum alloy and stainless steel: In the processing of such materials, the auxiliary gas used is nitrogen, which does not burn during cutting. However, because of the high temperature of the material inside the pore, the phenomenon of slagging on the inside will be more frequent.
The solution to this problem is to increase the pressure of the auxiliary gas and to set the condition as the pulse condition of high peak output and low frequency.
When the auxiliary gas is used in air, it will not overburn, but it is easy to appear slags at the bottom. It is necessary to set the conditions as high auxiliary gas pressure, high peak output, low frequency pulse condition.