What can be inferred from the presence of clustered magnetic particles during an MPT inspection?

The presence of clustered magnetic particles during a Magnetic Particle Testing (MPT) inspection indicates that there may be surface discontinuities present. This clustering occurs when magnetic particles gather around areas of flux leakage, which is typically associated with defects like cracks or voids on the surface of the material being inspected.

When there are no defects, the magnetic particles would distribute uniformly, rather than cluster. Therefore, clusters are a sign that the magnetic field is disrupted, signaling potential issues that require further investigation. Identifying these clusters allows inspectors to pinpoint where defects might exist and assess the integrity of the component. Ultimately, the appearance of clustered particles is a direct hint that there might be flaws, making it crucial for inspectors to closely examine these areas for surface discontinuities.