Magnetic Particle Inspection

Magnetic particle testing uses electrically induced magnetic fields in parts made from ferromagnetic materials to detect flux leakage at the site. Primarily used for surface and sub-surface defects. The speed and relative simplicity of this technology make it ideal for high volume applications.

While limited to examining parts made from iron and steel which are strongly affected by magnets (ferromagnetic), magnetic particle testing is, none the less, very useful for detecting minute surface and near-surface cracks down to a depth of about 0.100".

A magnetic field is induced in the test specimen, which is then "dusted" with iron particles, either dry or in a liquid suspension. The particles will collect along the edges of any cracks or other discontinuities that distort the induced magnetic field to provide a readily visible indication of the flaw.