In Situ Eddy-Current Testing on Low-Pressure Turbine Blades of Aircraft Engine

To realize in situ testing on low-pressure turbine blades of aircraft engines, eddy-current testing was studied through probe design, artificial defect sample testing, and practical field applications. The eddy-current probe was composed of a differential coil with dual magnetic cores, flexible spring steel strip, and elongating composite shank, which, respectively, provided high detection sensitivity on the turbine blade defect, appropriate contact between the probe and the curving blade surface, and adequate extent for the long distance of in situ inspection. Practical applications in engine turbine blades testing proved that the eddy-current probe successfully solved the in situ testing difficulties, including poor accessibility, limited detection space, and strong interference signals.