In view of the rough and sunken bottom of blind hole during the laser processing on carbon fiber-reinforced plastics (CFRP), a processing experiment with different hatch distance is conducted by picosecond laser, and the numerical simulation is carried out by COMSOL. The effects of scanning path distribution of hatch distance with equal and variable hatch distance in the processing depth, heat-affected zone and bottom micro-morphology of blind holes are studied. The results show that the variable hatch distance machining path can make heat more uniform on the material, so that the concave effect of the inner ring bottom is weakened. Moreover, the variable hatch distance path can reduce the fiber breakage and resin residue of blind holes, and enhance the physical performance of the structure. When the processing path is three sets of concentric circles with 70 µm innermost hatch distance and 100 µm outermost hatch distance, the machining depth can be achieved, and high-quality blind hole can be obtained under the premise of smaller heat-affected zone and borehole taper.

中文翻译：

---

碳纤维增强塑料盲孔皮秒激光加工研究

针对碳纤维增强塑料（CFRP）激光加工盲孔底部粗糙凹陷的问题，采用皮秒激光进行了不同舱口距离的加工实验，并在COMSOL上进行了数值模拟。研究了等间距和可变间距的舱口距扫描路径分布对盲孔加工深度、热影响区和底部微观形貌的影响。结果表明，变舱口距加工路径可使材料受热更均匀，从而减弱内圈底的凹入效应。此外，可变舱口距离路径可以减少盲孔的纤维断裂和树脂残留，增强结构的物理性能。