Film cooling holes (FCHs) of nickel-based single crystal turbine blades were drilled by 532 nm Nd:YVO₄ nanosecond laser in coaxial waterjet-assisted environment. Microstructure of the side wall of the FCHs was mainly investigated by means of transmission electron microscopy. The average thickness of heat affected zone (HAZ) around FCHs decreases with increasing of water flow rate. The main phase within HAZ evolves from β-NiAl to β-NiAl + γ-Ni with the increase in the water flow rate. Some γ-Ni particles in the HAZ twined along (111) plane. A small portion of the FCHs are free of HAZ when drilled by coaxial waterjet-assisted laser drilling at a laminar water flow rate ≥3.1 m/s. There are no processing-induced defects including HAZ, microcrack, and phase transformation around the FCHs when drilled at the water flow rate ≥5.1 m/s. The FCHs with high surface quality can be drilled by the coaxial waterjet-assisted laser drilling. Finally, effects of fluid water on drilling quality of the FCHs were discussed.

在532 nm Nd：YVO _4上钻出镍基单晶涡轮叶片的薄膜冷却孔（FCH）同轴水刀辅助环境中的纳秒激光。FCH侧壁的微观结构主要通过透射电子显微镜研究。FCH周围的热影响区（HAZ）的平均厚度随着水流量的增加而减小。随着水流量的增加，热影响区的主要相从β-NiAl演化为β-NiAl+γ-Ni。HAZ中的某些γ-Ni粒子沿（111）平面缠绕。当以层流水流速≥3.1m / s的同轴水射流辅助激光钻孔进行钻孔时，一小部分FCH没有HAZ。当水流量≥5.1m / s时，在FCH周围没有加工引起的缺陷，包括热影响区，微裂纹和相变。可以通过同轴水射流辅助激光钻孔来钻出具有高表面质量的FCH。最后，