Laser irradiation of dispensed tungsten powder layers with grain sizes smaller than 1 μm was investigated using high-repetition femtosecond laser systems. Laser processing was performed line by line with repetition rates up to 1 MHz and varying parameters such as laser power, processing speed, number of scans and pressure. In addition to the expected material ablation and melting, nov-el phenomena such as crystallisation, emergence of ripple structures, extensive agglomeration and the formation of nano-wires will be discussed qualitatively with the help of SEM photographs. De-pendence on light pressure, pulse overlap and irradiated energy per unit length will be demonstrated. High-resolution microstructures will be discussed as a first application of innovative laser microsin-tering technology using high-repetition femtosecond laser pulses.
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