MT – MAGNETIC PARTICLE TESTING

One of the very common methods of checking the surface of products made from magnetic materials. It is based on the principle of stray fields, where the magnetic field over the defect rises above the surface. Due to this effect we can make the identified defect visible, using appropriate means – dry magnetic dust, or its suspension usually in water.

Magnetic particle testing focuses namely on the defects of materials communicating with the surface. Similarly to the penetration method it serves to find and make visible the surface defects, plus it allows to identify incompleteness close to the surface that does not directly communicate. Like the penetration method it demands certain quality of the tested surface. The testing is performed for various material types, always ferromagnetic (impossible to use e.g. on austenitic steel).