航发涡轮叶片气膜孔的磨削加工实验

Experimental Study on Grinding Approach of Film Cooling Hole of Aero-Engine Turbine Blade

针对目前航空发动机涡轮叶片气膜孔加工精度低和重熔层难去除的问题,提出了"电火花打孔、磨削扩孔"的新型气膜孔加工工艺,研制出小孔磨削专用微细CBN砂轮并对电火花气膜孔进行了磨削工艺实验。实验结果表明:经磨削加工后气膜孔圆度降低50.9%,孔径尺寸标准差降低90.7%,表面粗糙度降低65.9%,重熔层被全部去除,证明了航发涡轮叶片气膜孔磨削加工的可行性。

For the problem that the machining precision of film cooling hole of aero-engine turbine blade is low and the recast layer is difficult to be removed. A new film cooling hole process which is mainly based on the thought of using EDM to drill and using grinding to expand is proposed. Grinding experiment was carried out on the film cooling hole machined by EDM using the special fine CBN grinding wheel. The result shows that after the grinding process, the roundness of the film hole is reduced by 50.9%, the standard deviation of the hole size is reduced by 90.7%, the surface roughness is reduced by 65.9%, and the recast layer is completely removed, proving the feasibility of the grinding approach of film cooling hole of aero-engine turbine blade.