A METHOD OF CALIBRATING AN EVALUATION ARRANGEMENT FOR SENSING MAGNETIC BARKHAUSEN NOISE.

摘要

A method of calibrating an evaluation arrangement for non- destructive evaluation of test objects on the basis of magnetic Barkhausen noise. The evaluation arrangement comprises a magnetization coil, a sensor for sensing magnetic Barkhausen noise, and an apparatus for evaluating the test object based on signals from the sensor. The method comprises creating a varying magnetic field of an expected magnitude, measuring the magnitude of the created varying magnetic field and determining a deviation from the expected magnitude, and adjusting the evaluation arrangement to compensate for said deviation. The evaluation arrangement is used in one of the steps of creating and measuring the varying magnetic field.