Fiber laser cutting machines two common perforation methods

At present, most of the laser cutting processes on the market are cutting and punching. Specifically, a small hole is opened in the middle of the sheet or tube, and then cut along the outward direction. A few of them can be cut directly from the edge. This is also a relatively basic processing requirement. Do you know what are the two common perforation methods for fiber laser cutting machines? 

Sandblast drilling: After the material is irradiated by continuous laser, the high-energy beam will form a pit on the surface of the material, and the molten material is removed by the coaxial airflow, and a hole is gradually formed. The diameter of the small hole is usually half the thickness of the plate, and the hole will appear large and not round when the thick plate is perforated. If the air pressure during piercing is the same as the cutting air pressure, it will cause the residue to splash during cutting and affect the appearance of the overall material.

Pulse drilling: Use a high peak power pulsed laser to melt or evaporate a small amount of material. Use air or nitrogen as auxiliary gas to reduce pore expansion caused by exothermic oxidation. When cutting, the nitrogen pressure is higher than the oxygen pressure. Each pulse laser only produces a jet of small particles, so it takes a few seconds to perforate a thick plate. After the perforation is completed, the auxiliary gas is immediately changed to oxygen for cutting.  For this reason, the laser equipment used should not only have a higher output power, but also need a more reliable gas path control system to realize the switching of gas types and gas pressure and the control of the perforation time.