Kerf overwidth
The technologically induced difference between the nominal beam diameter and the actual width of the generated kerf. It results from lateral heat conduction or the kinetic widening of the jet profile.
The kerf overwidth occurs because the laser beam not only acts in the desired area when cutting, but also melts the material laterally through heat conduction. If the kerf becomes too wide, you'll quickly have problems with distortion and stresses in the workpiece when welding, which can lead to cracking. Adjust the focus and power so that you get a clean, as narrow as possible kerf. If the kerf becomes too wide, go slower or reduce the power, but make sure the cut still goes through cleanly. You'll find the right setting through test pieces, you have to get a feel for your material and your machine.