Abstract CMSX-4 nickel superalloy specimens, in single crystal form, were prepared for in-situ machining trials using femtosecond pulse laser processing in a focussed ion beam scanning electron microscope. Preliminary laser ablation trials were carried out to establish the optimum focus distance. Various pillars were then prepared using the femtosecond laser, varying rectangular hatch pattern, scan speed, laser line separation and frequency. Polishing trials used helical laser hatch patterns to refine pillar shape and produce circular pillars with high aspect ratio. Example pillars were characterised by FIB-SEM cross-sectional examination to assess microstructural changes and re-deposition of vaporised material. The final selected laser parameters were able to produce a stable high-aspect ratio pillar in 4501 s, 1600 µm high with tip diameter 138 µm. An area 655 × 656 µm was cleared around the pillar with over 0.65mm3 of metal removed.

中文翻译：

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飞秒激光加工在单晶CMSX-4高温合金表面快速制备柱状结构

摘要 CMSX-4 镍高温合金样品制备为单晶形式，用于在聚焦离子束扫描电子显微镜中使用飞秒脉冲激光加工进行原位加工试验。进行了初步的激光烧蚀试验以确定最佳焦距。然后使用飞秒激光、不同的矩形填充图案、扫描速度、激光线间距和频率制备各种支柱。抛光试验使用螺旋激光阴影图案来细化支柱形状并产生具有高纵横比的圆形支柱。示例支柱通过 FIB-SEM 横截面检查进行表征，以评估微结构变化和蒸发材料的再沉积。最终选定的激光参数能够在 4501 s 内产生稳定的高纵横比支柱，1600 µm 高，尖端直径 138 µm。在柱子周围清除了 655 × 656 µm 的区域，去除了超过 0.65mm3 的金属。