What is the primary purpose of the magnetic particles in Magnetic Particle Testing?

The primary purpose of magnetic particles in Magnetic Particle Testing is to provide a means of visualizing surface defects. When a magnetic field is applied to a ferromagnetic material, any surface or near-surface discontinuities, such as cracks or inclusions, disrupt the magnetic field lines. When magnetic particles are introduced to the area, they aggregate at these disruptions, forming visible indications. This visibility allows inspectors to identify and assess the presence and severity of defects effectively.

Using magnetic particles aids in highlighting these defects in a way that is easy to interpret with the naked eye, thus facilitating quick and accurate inspections. The ability to visualize these flaws is crucial in various industries where structural integrity is paramount, ensuring that any potential weaknesses can be addressed before they lead to failure.