Micromachining of metals with ultra-short Ti-Sapphire lasers: Prediction and optimization of the processing time

We investigate the processing times of ultrafast laser machining in the case of metals (copper and stainless steel). At a fluence of 2.5 J/cm(2), measurements of processing times are in good agreement with the calculations based on the ablation rates. We study the influence of laser repetition rates for 1, 5, 10 and 15 kHz. A linear reduction of the processing time can be expected with an increase of the repetition rate.