Magnetic Particle Inspection

Magnetic particle inspection is a non-destructive testing process used to detect surface/subsurface cracks. MPI is performed with the application of fluorescent magnetic particle powder (wet or dry), coupled with a device (magnetic yolk/bench) that’s capable of generating a magnetic field around the sample to be tested. Due to the nature of the magnetic field, fluorescent magnetic particle powders are drawn into potential cracks/defects. Application of a blacklight (UV) will reveal the concentrated fluorescent magnetic particle that has been drawn into the defects/cracks, thereby revealing the structure of the defect.

An MPI bench (Magmaster 4000) is the primary device used at Donhad for magnetic particle inspections, the bench is capable of generating large amounts of magnetic flux such that large samples can be tested, either in several parts or at once. Integrated onto the bench is a blacklight and a pumping station (for fluorescent magnetic powder) to ensure ease of operation. For samples which cannot be moved around freely, a Magnetic yolk is used together with fluorescent magnetic particle power aerosols. MPI testing at Donhad is performed according to AS 1171 – 1998 (Australia Standard, Non-destructive testing – Magnetic particle testing of ferromagnetic products, components, and structures), ensuring the integrity of each test.