Abstract We report novel results on top-down percussion drilling in different glasses with femtosecond laser GHz-bursts. Thanks to this particular regime of light – matter interaction, combining non-linear absorption and thermal cumulative effects, we obtained crack-free holes aspect ratios exceeding 30 sodalime 70 fused silica. The are discussed terms inner wall morphology, ratio speed.

Abstract A simplified analytical model is presented that predicts the depth progress during and final hole obtained by laser percussion drilling in metals with ultrashort pulses. The based on assumption drilled microholes exhibit a conical shape absorbed fluence linearly increases of hole. calculated recursively changes induced successive experimental validation confirms its assumptions for sta...

The efficiency of a jet engine is improved by increasing the temperature in the engine combustion components. Combustion chamber temperatures have increased up to 1600° C over the past decade. Therefore, jet engine combustion components must deal with high temperatures. Free-air-flow cooling holes are critical for cooling the components. But the process of drilling cooling holes has numerous pr...

Among possible monitoring techniques, self-mixing interferometry stands out as an appealing option for online ablation depth measurements. The method uses a simple laser diode and interference is detected inside the diode cavity and measured as the optical power fluctuation by the photodiode encased in the laser diode itself. This way, self-mixing interferometry combines the advantages of a hig...