Magnetic Particle Testing

about magnetic particle testing

Magnetic Particle (MP or MPI) Testing shows indications of flaws on accessible surfaces of ferrous materials based on “the principle that the magnetic susceptibility of a defect is markedly poorer (the magnetic resistance is greater) than that of the surrounding material” (Wikipedia, 2007, September 8). With Magnetic Particle testing colored magnetic particles are scattered over a surface that the inspector then magnetizes externally. If there is a crack or other flaw, they become attracted to and build up along the area of defect. 

The images show the magnetic particle indications of cracks in a hot container housing.

the mp testing process

In Magnetic Particle testing, colored magnetic particles are scattered over a surface of the equipment being inspected. The inspector then magnetizes the particles externally. If there is a crack or other flaw, the particles become attracted to and build up along the area of defect.