Magnetic particle inspection (MT, MPI) is used to detect surface and subsurface defects at a depth not exceeding several millimeters.
Magnetic particle testing puts a magnetic field into the inspected specimen and detects local magnetic stray fields formed above the surface of the specimen at the point where the defect occurs. Therefore, this test can only be carried out on specimens made of ferromagnetic materials. Magnetic particle inspection does not require such thorough surface preparation as penetration testing, which makes it the most frequently used method for detecting defects such as cracks, hot tears, overlaps, cold shuts, scaling and non-metallic inclusions.
Magnetic particle examination involves two techniques: dye and fluorescent inspection (MT-UV).
Magnetic particle testing is performed in conformity with the following standards:
PN-EN ISO 12707:2016-07 - Non-destructive testing — Magnetic particle testing — Vocabulary
PN-EN ISO 3059:2013-06 - Non-destructive testing — Penetrant testing and magnetic particle testing — Viewing conditions
PN-EN ISO 9934-1:2017-02 - Non-destructive testing — Magnetic particle testing — Part 1: General principles
PN-EN ISO 9934-2:2015-11 - Non-destructive testing — Magnetic particle testing — Part 2: Detection media
PN-EN ISO 9934-3:2015-11 - Non-destructive testing — Magnetic particle testing — Part 3: Equipment
PN-EN ISO 17638:2017-01 - Non-destructive testing of welds — Magnetic particle testing
PN-EN ISO 23278:2015-05 - Non-destructive testing of welds — Magnetic particle testing — Acceptance levels
PN-EN 1369:2013-04 - Founding - Magnetic particle testing
PN-EN 10228-1:2016-07 - Non-destructive testing of steel forgings - Part 1: Magnetic particle inspection
PN-EN ISO 10893-5:2011 - Non-destructive testing of steel tubes — Part 5: Magnetic particle inspection of seamless and welded ferromagnetic steel tubes for the detection of surface imperfections
