Dipole modelling of temperature-dependent magnetic flux leakage

Due to the nonlinear coupling, assessing direct effect of temperature on magnetic flux leakage (MFL) signal is a complicated task. If induces inner stress, it makes problem doubly difficult, so few models are available for predicting MFL under this condition. To model signal, temperature-dependent dipole proposed. In first case, where thermal involved only, improved via modified Jiles-Atherton (J-A) model. While in second combined effects and stress considered, magnetomechanical J-A parameters further introduced into The distribution around cylindrical through-hole defect solved by thermoelastic solid mechanics theories. theory employed analyse stress-dependent magnetisation distribution, key parameter verified experiments conducted an M250-50A non-oriented grain (NO) silicon steel specimen with defect. And signals predicted both proposed agree experimental results. When peak-to-peak amplitude (MFL pp ) presents approximately linear dependence range from ?40 °C 60 . addition, when changes as parabolic function temperature, being much more significant than effect. can act effective tools understand influences signals. They also appropriate solve inverse sizing defects accurately involved.