Abstract This work investigates the influence of pulse energy on machining characteristics using a 10 ps laser during Laser induced plasma micromachining (LIPMM) process. An axisymmetric model combining the effects of cascade, multiphoton ionization, and recombination and diffusion losses was developed to simulate the spatial and temporal plasma profiles at various pulse energies in distilled water. Thereafter, micro-channels with the corresponding pulse energies were created on stainless steel using LIPMM, and the plasma focusing process, depth and width of the machined channels were investigated. It was found that pulse energy had a negligible effect on the variation of the focusing distance during the LIPMM focusing process. The simulations and experimental geometric features showed similar qualitative trends with the increasing pulse energy at the plasma’s focal plane. However, the pulse energy had a significant influence on the machined depth, but a much lesser influence on the machined width.

中文翻译：

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激光诱导等离子体微加工中脉冲能量对加工特性的影响

摘要 这项工作研究了在激光诱导等离子体微加工 (LIPMM) 过程中使用 10 ps 激光器的脉冲能量对加工特性的影响。开发了一个结合级联效应、多光子电离效应以及复合和扩散损失的轴对称模型，以模拟蒸馏水中各种脉冲能量下的空间和时间等离子体分布。此后，使用 LIPMM 在不锈钢上创建具有相应脉冲能量的微通道，并研究了等离子体聚焦过程、加工通道的深度和宽度。结果表明，脉冲能量对 LIPMM 聚焦过程中聚焦距离变化的影响可以忽略不计。随着等离子体焦平面上脉冲能量的增加，模拟和实验几何特征显示出类似的定性趋势。然而，脉冲能量对加工深度有显着影响，但对加工宽度的影响要小得多。