Magnetic Particle Testing (MT)

Magnetic particle testing (MT) is used to detect discontinuities in ferromagnetic parts – namely parts made of iron, steel, nickel, cobalt and the alloys of these materials

MT is a highly effective inspection tool that is sensitive to the presence of cracks, laps, seams and similar types of surface and near-surface discontinuities

Magnetic Particle Testing


  • Low-cost, reliable method for locating surface cracks in ferromagnetic materials.
  • Particles may be in color or made to fluoresce under ultraviolet radiation.
  • Permanent magnets can be used.
  • Fast and simple application process.
  • In addition, the discontinuity location, orientation and approximate length are indicated on the part, making interpretation and evaluation possible
  • Visual interpretation of indications


  • Can be used only on ferromagnetic materials
  • Large electrical currents are required for certain test applications
  • Correct selection and process of application of particles can severely limit sensitivity
  • False indications often occur in transition areas
  • Burning of parts can occur at contact points