Non-destructive method for the detection of creep damage in ferromagnetic parts with a device consisting of an eddy current coil and a hall sensor

Non-destructive method for the detection of creep damage present in ferromagnetic power plant components. First a measurement device consisting of an eddy current coil and a hall sensor with a magnetisation joke is manufactured. The measurement device is calibrated with tensile calibration specimens with defined creep strain by measuring the most significant NDT (non-destructive techniques) relevant measured properties (e.g. multi-frequency eddy current, upper harmonics analysis of tangential magnetic field strength, incremental permeability and Barkhausen noise). A multi-regression method is used for the correlation between NDT relevant measured properties and the defined creep strain. The calibrated measurement device is used for measurement of the creep strain present in said power plant components.