Preparation method of turbine blade defective part

The invention discloses a preparation method of a turbine blade defective part. The method adopts an ultrafast picosecond micropore processing machine tool to perform crack etching on a turbine blade, and comprises the following steps: taking a normal turbine blade test piece without defects, and clamping the taken turbine blade on a turntable of an ultrafast picosecond micropore processing machine tool through a clamp; correcting the processing surface of the turbine blade test piece by using a distance measuring probe on the ultrafast picosecond micropore processing machine tool, so that the crack etching direction of the turbine blade test piece is parallel to the processing direction of the ultrafast picosecond micropore processing machine tool, and capturing an initial processing point; setting numerical control machining parameters of an ultrafast picosecond micropore machining machine tool according to the size and the shape of the pre-etched crack on the turbine blade test piece; and starting the ultr