Laser-induced periodic surface structures (LIPSS) can be produced in a single step on metals, semiconductors or dielectrics. Since they allow a significant improvement of the surface functionalities, they are a subject of an intensive research. In this thesis, we used a nanosecond fiber laser having variable pulse duration and a wavelength of 1060 nm. We upgraded the laser system by a polarizer to demonstrate that in this way it is possible to obtain LIPSS without the use of expensive ultrashort laser systems. This new approach will significantly expand the possibilities for implementation of this kind of laser microstructuring into different industrial areas. By pulses we irradiated the stainless steel. Firstly, we measured the fluence threshold for material ablation; in our case it equals 3,7 J/cm2. Then, we examined how different marking directions, the average laser power and the position of the sample out of the focal position influence the LIPSS formation. The results show that LIPSS occurs when the peak fluence is within 0.91.4 times of the threshold for material ablation. In this case, LIPSS has a period roughly equal to the laser wavelength. In most cases LIPSS orientation does not depend on the texturing direction. However, there are certain parameters where LIPSS orientation changes with the texturing direction. We have also shown that the periodic structures are more pronounced when the sample is positioned slightly out of the focus. As an example of surface functionalization, we evaluated the colors appearing on the surface due to LIPSS. A key thesis conclusion is the proof that a nanosecond fiber laser can also be used to functionalize the surfaces with LIPSS. This opens up new possibilities for technological breakthroughs in many areas where the costs of surface processing are of key importance.
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