Examples of Visible Dry
Magnetic Particle Indications
One of the advantages that a magnetic particle inspection has over some of the other nondestructive evaluation methods is that flaw indications generally resemble the actual flaw. This is not the case with NDT methods such as ultrasonic and eddy current inspection, where an electronic signal must be interpreted. When magnetic particle inspection is used, cracks on the surface of the part appear as sharp lines that follow the path of the crack. Flaws that exist below the surface of the part are less defined and more difficult to detect. Below are some examples of magnetic particle indications produced using dry particles.
Indication of a crack in a saw blade
Indication of cracks in a weldment
Indication of cracks originating at a fastener hole
Before and after inspection pictures of cracks emanating from a hole
Indication of cracks running between attachment holes in a hinge