In the master's thesis we develop and build a laser system enabling microdrilling and structuring of various metal surfaces on micrometer and submicrometer scale, by different laser sources: Nd:YAG laser ( = 1064 nm) with ultrashort 8-ps and 30-ps pulses; and a fiber laser ( = 1064 nm) with pulses of variable lengths, from 10 ns to 240 ns. Microdrilling was performed into 28-m-thick steel foil and 32-m-thick titanium foil, while the surface structuring was carried out on polished samples of steel, titanium and aluminium. Processed surfaces have been characterized using optical microscope, scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS). Results show, that microholes with diameters in range of the laser wavelength (~1 m) can be laser drilled. The effect of beam polarisation on the shape of the holes is also presented. We have investigated the effect of processing parameters on growth, period and orientation of laser-induced periodic surface structures (LIPSS). Evaluation of changes in surface chemistry (mass fraction of oxygen) with dependence on total irradiated pulse energy shows that the oxygen content is increasing with total pulse energy up to a saturation level, which in our case equals 18%. We explain different reasons for coloring of metals and present the effect of surrounding atmosphere on development of hierarchical surface structures. The accomplished results are important for further development of new surfaces with unique functionalities.
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