In order to solve the problems of forming process of turbine blade of aero-engine film cooling holes

such as severe heat effect

a helix drilling and spiral drilling processing method for microholes by ultrafast laser was proposed

and a double power laser system was designed for machining of film cooling holes efficiently and without heat effect; the reason of heat effects was analyzed from two aspects of action mechanism and actual machining process; the main influential factors were pointed out and the optimization of process parameters and experimental verification targeting at these factors were processed using DD6 material. The experimental results show that the composite processing method using 500fs laser and microseconds laser can increase fine drilling efficiency about 10 times

and can also process the film cooling holes on turbine blades without recast layer and micro-cracks; the process parameters include beam scanning speed of 2400r/min

overlap rate of 12%

feeding amount of 5μm

repetition frequency of 20kHz and coaxial blow with the air pressure of 0.6Pa. They also show that ultrafast laser with reasonable process parameters and processing methods can process film cooling holes without heat effects

so it is an effective technological method to improve the surface integrity of film cooling holes.