アモルファスMIセンサを用いた2方向センシングおよび 漏洩磁束密度分布関数のパラメータによる欠陥深さと欠陥位置の評価
Evaluation of Depth and Location of Defects Based on 2-Axis Sensing with Amorphous MI Sensors and Parameter Evaluation of Leakage Flux Density Function
著者:
安部 正高 Masataka ABE 琵琶 志朗 Shiro BIWA 松本 英治 Eiji MATSUMOTO
発刊日:
公開日:
Amorphous MI SensorAxis SensingMFL TestingNondestructive Testing
概要
There are few works using 2-dimensional measurement in Magnetic Flux Leakage testing. We attempt to estimate the flaw depth and distinguish front or back surface flaw by estimating horizontal component Bx and vertical componen t B, of the magnetic leakage flux density from magnetic structural material. We first calculate the distribution of magnetic flux density near a specimen surface by use of FEM analysis. The distribution is assumed to be approx imated by exponential function according to the dipole model of MFL. It is found that the horizontal location and the depth of the flaw can be measured by the parameters of approximated distribution function. It is also shown that front surface or back surface flaw can be distinguished by correlation of two parameters. In order to verify the theoretical result, we carry out an experiment on SS400 steel strip with several depths of artificial flaws.
