Abstract The formation and properties of laser-induced periodic surface structures (LIPSS) were investigated on carbon fibers under irradiation of fs-laser pulses characterized by a pulse duration τ = 300 fs and a laser wavelength λ = 1025 nm. The LIPSS were fabricated in an air environment at normal incidence with different values of the laser peak fluence and number of pulses per spot. The morphology of the generated structures was characterized by using scanning electron microscopy, atomic force microscopy and Fast-Fourier transform analyses. Moreover, the material structure and the surface chemistry of the carbon fibers before and after laser irradiation was analyzed by micro Raman spectroscopy and X-ray photoelectron spectroscopy. Large areas in the cm2 range of carbon fiber arrangements were successfully processed with homogenously distributed high- and low-spatial frequency LIPSS. Beyond those distinct nanostructures, hybrid structures were realized for the very first time by a superposition of both types of LIPSS in a two-step process. The findings facilitate the fabrication of tailored LIPSS-based surface structures on carbon fibers that could be of particular interest for e.g. fiber reinforced polymers and concretes.

中文翻译：

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在碳纤维上大面积制造低频和高频激光诱导的周期性表面结构

摘要 研究了在 fs 激光脉冲照射下碳纤维上激光诱导周期表面结构 (LIPSS) 的形成和性质，其特征在于脉冲持续时间 τ = 300 fs 和激光波长 λ = 1025 nm。LIPSS 是在空气环境中以垂直入射的方式制造的，具有不同的激光峰值通量值和每个光斑的脉冲数。通过使用扫描电子显微镜、原子力显微镜和快速傅立叶变换分析来表征所生成结构的形态。此外，通过显微拉曼光谱和X射线光电子能谱分析了激光照射前后碳纤维的材料结构和表面化学。碳纤维排列的 cm2 范围内的大面积使用均匀分布的高和低空间频率 LIPSS 成功处理。除了那些独特的纳米结构，混合结构是第一次通过在两步过程中叠加两种类型的 LIPSS 来实现的。这些发现有助于在碳纤维上制造定制的基于 LIPSS 的表面结构，这可能对纤维增强聚合物和混凝土特别感兴趣。