Magnetic Particle Testing
Identify Defects with Magnetism
Magnetic particle testing, also referred to as magnaflux testing, identifies surface and near-surface defects in products that can be magnetized. Because magnetization of certain metals is possible, small particles that are attracted to magnetic fields are applied to the surface of the test material, either after or during induction of a magnetic field. Magnetic particle testing is performed with either a wet solution or dry powder containing magnetic iron particles. The magnetic field causes the particles to accumulate in flaws such as cracks, laps and seams.
Wet fluorescent magnetic particle testing is performed most often at Laboratory Testing Inc. with a solution of very small particles contained in a liquid carrier. The wet solution has an advantage over the dry in that it is easily sprayed, flows well to small leakage fields and the fluorescence allows the particles to be seen without difficulty. The Lab’s magnaflux testing machines provide a maximum output of 6,300 amps and can handle products that are up to 12 ft. long. LTI also performs magnetic particle testing using the visible dry powder method, when the wet fluorescent method is not an option for certain products.