In this dissertation, we investigate the process of laser ablation during macroscopic removal of two industrially interesting materials (AISI 316L steel and CuZn37 brass) using high repetition rates (> 10 kHz). We studied the influence of selected environmental parameters, laser system parameters, and material properties on the material removal rate (MRR), energy efficiency of the process, and quality of the laser-treated surface using nanosecond pulses at a wavelength of 1064 nm emitted by a Yb fiber laser. The results show that the MRR increases monotonically with pulse duration, while it increases linearly with repetition rate up to the characteristic value (f0) at which both the pulse energy and the average laser power are highest. The maximum MRR is reached at a repetition rate higher than or at most equal to f0. The exact value of the extreme depends on the correlation between the repetition rate and the fluence of the laser pulses, as well as on the material properties of the sample. The degree of overlap has a significant effect on the surface roughness (Sa), and the best ratio between ablation rate and surface quality is achieved at about 50 % overlap of the laser pulses, regardless of the material being processed. We have successfully applied these findings to real industrial examples (dynamic balancing of polypropylene rotors in motion and surface micromachining of magnetoactive elastomers), demonstrating that the presented approach is relatively universal, as we were able to apply it to metals (steel and brass) as well as to hard (glass fiber reinforced polypropylene) and soft (polydimethylsiloxane with iron inclusions) composite materials.
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