In final thesis »Laser surface remelting of carbon steel C15 and C45« are presented methodology of an experiment and evaluation of the obtained results of microstructures and microhardness as result of laser surface remelting with Nd:YAG laser of two carbon steels with or without Ar gas protection. With help of measuring depths,widths and microhardness of remelted and heat-affected area and base material, we determined the optimal process parameters, whose goals were to harden material as much as possible and while doing that, we also wanted the biggest efficiency Based on the analysis of the results of microstructures and microhardnesses, it turned out that for given constant and changing values, the optimal processing parameter for C15 was obtained when using the beam energy E = 13.7 J and for C45 at E = 11.9 J. Beside mentioned beam energies, we also had constant parameters like t = 8ms, f = 4 Hz, v = 1.5 mm/s and Φv_Ar = 2 l/min.
After evaluating the measurements, we could see that C45 is a much more suitable material for laser hardening of surfaces as C15, since it begins to remelt at lower powers and in addition, also remelting and heat input into material throught the whole process is more intense to the depth of material.
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