What does "multi-directional magnetization" enhance in MPI?

Multi-directional magnetization enhances the application of magnetic force in multiple directions, which is crucial for effective magnetic particle inspection (MPI). This technique involves magnetizing a test object in two or more orientations rather than just a single direction. By doing so, it allows for better detection of surface flaws that can exist in various orientations, which may not be detected if the magnetization was applied unidirectionally.

When a component is magnetized in multiple directions, magnetic fields can penetrate deeper into the surface and reveal defects that might be aligned in different directions. This comprehensive approach ensures that different types of discontinuities—such as cracks or laps—are more likely to be indicated by the movement and clustering of magnetic particles, significantly improving the likelihood of finding defects that are critical for structural integrity.

While the cohesion of magnetic particles, stability of the magnetic field, and visibility of surface defects are important aspects of MPI, they are not directly enhanced by the multi-directional application of magnetic force itself. Instead, multi-directional magnetization focuses specifically on optimizing how magnetic fields are applied to reveal flaws effectively.