| 摘要 |
<p>A method of detecting magnetic discontinuities in a test sample of magnetic material includes the steps of generating a magnetic field in said test sample, placing one or more magnetic sensors adjacent said test sample for the detection of magnetic leakage flux, if any, adjacent the surface of the test sample, and generating electric signals representing the leakage flux, if any, said sensors being moved across the surface of the test sample. Each sensor (7) carries out a scanning movement substantially transverse to the advancing direction during the advancing movement. In this manner it is sufficient to observe whether the output signal of the sensor discloses sudden changes during a scanning. As a result, the associated electronics can be simplified.</p> |
