Magnetic Particle Testing

Magnetic Particle Testing

The magnetic particle testing method (MT) is one of the most sensitive, reliable and productive NDT-methods for surface testing of products from ferromagnetic materials. The method is based on the attraction of ferromagnetic particles by force of leakage flux which appears above surface defects like cracks, laps, lacks of fusion, and pores after an adequate magnetisation. MT can be used for indication of open surface defects and under certain conditions for detection of near-surface defects. A higher probability of detection is achievable if the direction of a defect is oriented perpendicularly to the direction of the applied magnetic field. The smaller is the angle between the defect and magnetic field lines, the weaker will be the indication.