Investigation of cumulative effects during fs-laser-material-processing with average powers of several 100 W

由于脉冲宽度小于电子-声子耦合时间和强度远高于蒸发阈值，超短脉冲激光辐射具有精确的材料加工的潜力，几乎任何材料与非常低的热输入.由于现有激光系统的平均功率小，飞秒激光材料加工在大多数情况下都太慢，不适合工业应用。随着offs激光系统的发展，平均功率为100 W，材料加工具有足够的生产力，可用于工业应用。但是，随着fs激光材料加工的规模扩大到高平均功率（即高脉冲能量和/或高重复率），不希望的效应，如热积累和等离子体屏蔽，可能会降低生产率和质量的过程。在这个建议中，这种累积效应在飞秒激光材料加工过程中具有高的平均功率，特别是与单脉冲加工过程中的效应的相关性将被研究。通过这种方式，我们可以理解这些潜在的过程和相互关系.

Due to pulse durations smaller than the electron-phonon coupling time and intensities well above theevaporation threshold ultrashort pulsed laser radiation has the potential for precise material processing ofnearly any material with very low heat input. Due to small average powers of available Laser-systems, fs-lasermaterial processing is too slow for industrial applications in most cases up to now. With the development offs-Laser-systems with average powers of multiple 100 W material processing with sufficient productivity forindustrial applications is enabled. But with the up-scaling of fs-laser-material processing to high averagepowers (i.e. high pulse energy and/or high repetition rate) undesired effects like heat accumulation and plasmashielding can lower the productivity and quality of the processes. In this proposal such cumulative effectsduring fs-laser material processing with high average powers and in particular the correlation to effects duringprocessing with singe pulses shall be investigated. In this way an understanding of the underlying processesand correlations shall be developed.