Magnetic Particle Inspection
Magnetic particle inspection is performed on ferrous alloys to locate both surface and sub-surface flaws. This method utilizes electromagnetism produced from electrical current to generate north and south poles within the test article, similar to that of a standard magnet. Extremely fine fluorescent particles of iron suspended in solution cover the test part. When viewed with the black (ultraviolet) light, flaws will present themselves as bright, fine, sharp indications.