The non-destructive testing technology Magnetic Particle Inspection or MT as it is generally referred to is a simple crack detection tool for ferrous materials. MPI is used mainly for detecting surface breaking flaws. Some techniques will detect large sub-surface flaws. There are several levels of sensitivity and means of inducing magnetic fields in materials. The technique is determined by specific application and configuration of part to be inspected. In order to perform this inspection technique, it is a requirement to remove all coatings and have surface clean of dirt, scale and grease.
MPI will detect flaws perpendicular to the magnetic field, for this reason it is necessary to magnetise the material in at least two directions.
During MPI the iron particles are in either dry or wet form. In wet form they are either oil or water based.
