Magnetic particle testing (MT)
Magnetic particle testing is used to detect surface and large, shallow subsurface discontinuities using electromagnetic field dispersion. To perform MT, surfaces need to be cleaned and oil must be removed. Subsequently, surfaces are magnetized and a dry or wet magnetic suspension is applied enabling an inspection to take place. The surface is then demagnetized and cleaned. Magnetic particle testing can be applied during different stages of production and operation, on the entire surface or locally. This method is more accurate than penetration inspection. MT can be used only on ferromagnetic materials.