涡轮叶片气膜孔的纳秒-飞秒双波段激光加工

Process of Turbine Blade Film Cooling Holes by Nanosecond and Femtosecond Laser Pulses

针对航空发动机中涡轮叶片气膜孔的复杂加工要求,提出并建立了一套基于纳秒–飞秒双波段激光加工的方法与系统。使用三维扫描仪对涡轮叶片气膜孔进行空间坐标获取,对气膜孔的实际加工坐标进行了误差校正,实现了气膜孔的高精度定位。综合利用532nm纳秒激光高效率与400nm飞秒激光高精度的特点,在不锈钢涡轮叶片上实现了81个气膜孔的高精度、高质量加工。孔径一致性达到±10μm,定位精度小于50μm。工业计算机层析成像检测以及高倍显微镜检测的结果表明,气膜孔孔形良好,内壁无交叉、孔壁光滑、无明显重熔层与微裂纹。

To meet the demand of strict process of turbine blade film cooling holes in aero-engine,a method was proposed and a system was set up based on nanosecond laser and femtosecond laser pulses.A 3D scanner was used to compensate errors of coordinates accurately in process of film cooling holes.Combining high-efficiency feature of 532nm nanosecond laser with high-precision feature of 400nm femtosecond laser,eighty-one film cooling holes were processed in each of stainless-steel turbine blades.Deviations of the diameter are kept within 10μm and the position errors are no more than 50μm.Profiles of film cooling holes are in good condition and no resolidified layer or microcracks are found under the detection of industrial computer tomography and high magnification microscope.High-quality film cooling holes are processed with no interference.