Magnetic Particle Inspection / Magnetic Particle Inspection
Magnetic particle Testing is a method of locating and defining discontinuities in magnetic materials It is excellent for detecting surface defects in welds, including discontinuities that are too small to be seen with the naked eyes, and those that are slightly subsurface. This method may be used to inspect plate edges prior to welding, in process inspection of each weld pass or layer, post weld evaluation and to inspect repairs. It is a good method for detecting surface cracks of all sizes in both the weld and adjacent base metal, subsurface cracks, incomplete fusion, undercut and inadequate penetration in the weld, as well as defects on the repaired edges of the base metal. Although magnetic particle testing should not be a substitute for radiography or ultrasonic’s for subsurface evaluations, it may present an advantage over their methods in detecting tight cracks and surface discontinuities.