The mechanism study of the annulus reference block on magnetic particle testing

In order to analyze the mechanism of annulus reference block controlling overall properties of magnetic particle testing,a simplified mathematical model of magnetic flux leakage(MFL) was developed.The MFL of circle hole in the annulus reference block was calculated by solving Lapalaceps equation of scalar magnetic potential;the stresses of magnetic particle on the annulus reference block were also calculated.At last,conclusions were obtained by analyzing the characters of the testing signals.