When a ferromagnetic workpiece is placed in a magnetic field, magnetic field lines are directed toward and through the workpiece. If the magnetic field lines act on the crack, the magnetic field lines will not be continuous and will overflow the surface of the workpiece, thus producing magnetic poles on both sides of the crack. Spray magnetic powder (or magnetic suspension) on the surface of the defective workpiece, and the magnetic powder will form an obviously visible line at the crack (Figure 1). The color of the magnetic powder should be chosen to have a greater contrast with the surface of the workpiece as much as possible, which will make it easier for defects to be observed by the human eye (this equipment uses fluorescent magnetic powder). This is the basic testing principle of magnetic particle testing.
| Product Name | CEW-8000 AC and DC half-wave fluorescent magnetic particle flaw detection machine |