Reason and Improvement Method of Excessive Background in Fluorescent Penetrant Inspection of Vanes

The fluorescence background of compressor rotor blade is excessive when it is detected by fluorescence penetrant inspection. After the first and the second removing of the oxide film, the cause of excessive background is that the oxide film on the surface of the blade is removed incompletely. Therefore, a visual inspection process is added before the fluorescent penetration test of the compressor rotor blade to ensure the surface oxidation of the blade is removed completely.