陶瓷基复合材料因其优异的机械性能和耐高温特性成为航空发动机热端构件的优选材料，由于其高硬度、高脆性、低导电性的材料特点，导致小孔径、大深径比、变截面结构的锥形气膜冷却孔加工成为难题，飞秒激光加工是解决该难题的有效方法。基于锥孔结构，设计了正螺旋轨迹和负螺旋轨迹，并采用倾斜激光束的两步旋切钻孔方法实现了SiCf/SiC复合材料上正锥孔和负锥孔的高质量加工。加工后锥孔出入口尺寸误差≤3 μm，锥度误差≤0.02°；入口边缘覆盖有少量沉积物，出口无沉积物，边缘锋利；正锥孔和负锥孔孔壁形貌均匀，可以观察到被平整去除的纤维和基体结构，孔壁粗糙度Sa分别为1.8 μm和2.5 μm左右。对锥孔的形成过程进行了研究，分析了孔底形貌、出入口尺寸的演变过程，阐明了锥孔的孔轮廓创成机制，为SiCf/SiC复合材料热端部件锥孔的高质量加工提供了工艺基础及质量评价参考。

Ceramic matrix composites stand out for excellent mechanical properties and high temperature resistance, making them promising for hot-end components of aircraft engines. Due to their high hardness, brittleness, and low conductivity, processing conical film cooling holes with small aperture, large aspect ratio, and variable cross section has become a challenge. Femtosecond laser processing is an effective method to solve this issue. Based on the conical hole structure, positive and negative helical path were designed, and a two-step rotary drilling method using an inclined laser beam was adopted to achieve high-quality machining of positive and negative con-ical holes in SiCf/SiC composite materials. The dimensional error of the conical hole entrance and exit is ≤ 3 μm, and the taper error is ≤ 0.02°; There is a small amount of deposition at the entrance edge, while the exit is free of deposition and has sharp edge; The wall morphology of both the positive and negative conical holes was uniform, with clearly fibers and matrix structures that have been uniformly removed. The surface roughness (Sa) of the hole walls is approximately 1.8 μm for the positive conical hole and 2.5 μm for the negative conical hole. The formation process of the conical holes is studied, and the evolution of the bottom morphology and entrance/exit dimensions is analyzed. The hole profile formation mechanism is clarified, providing a processing foundation and quali-ty evaluation reference for high-quality machining of conical holes in SiCf/SiC composite hot-end components.