Common problems and solutions for laser cutting thick metal plates

1. Perforation problem of carbon steel thick plate
The issue of perforation time accounts for a large proportion in thick plate processing, and various laser manufacturers have developed their own perforation plans. The most representative one is energy perforation (blasting), which has the advantage of fast speed (1 second, taking t16mm as an example - the same below), but the defect is that it affects the processing of small shapes. The energy injected during perforation raises the temperature of the plate and affects the overall cutting process. If low-power pulses are used for perforation, the time will be very long (12 seconds), resulting in a decrease in cutting efficiency.

2. Quality issues with the cutting surface
When processing medium and thick plates, it is common to encounter cutting section problems, which raise doubts about the quality of the cut products and are accompanied by overburning and severe slag sticking, making it difficult to distinguish the value of expensive laser processing machines from other cutting methods.

3. Stability issues during whole board processing
In the whole board processing, there is often a phenomenon of poor processing in local areas. This phenomenon is sometimes very random, even when the processing machine is in good condition. The handling of local faulty products greatly affected the entire work schedule.
Solution:

1. Peak perforation: As the name suggests, it is the use of high peak pulse laser with a small duty cycle, supplemented by non fuel sprayed on the surface of the material to remove the adhesion at the edge of the opening, and control the reasonable frequency of the pulse while cooling and perforating.

2. For carbon steel, the important factor in changing the cutting section is to control the heating of the plate and achieve the combustion of the laser irradiated part. For stainless steel, the important factors in cutting the cross-section are the improvement of the beam and the utilization of gas.

3. Solution for processing stability: Adopting an equal length optical path method (where the optical propagation path between the light source and the processing head is equal within the machinable range) can reduce changes in depth of focus, thereby maintaining the same spot and depth of focus.