Which magnetization methods are commonly used in magnetic particle inspection to reveal defects at different orientations?

Which magnetization methods are commonly used in magnetic particle inspection to reveal defects at different orientations?

• A. Transverse and radial
• B. Circular and longitudinal
• C. Longitudinal only
• D. Circular only

Answer: (B)

Magnetic particle inspection reveals defects by causing leakage fields where the magnetic flux is disrupted by a flaw. Different defect orientations will disturb the flux in different ways, so using more than one magnetization direction helps reveal cracks and other flaws no matter how they lie on the surface. Circular (circumferential) magnetization creates a field around the part’s circumference. This makes defects that run across the surface or perpendicular to the first field create leakage fields at their ends, drawing particles to those locations. Longitudinal magnetization runs along the length of the part. Defects oriented parallel to the length will disturb the flux in a way that produces leakage along the defect, making it detectable. Using both orientations together covers defects in multiple directions, increasing the likelihood of visibility for cracks oriented variously. Radial or nonstandard magnetization schemes aren’t typically used in routine MPI, and relying on only one direction can miss flaws that don’t align with that field.

Magnetic particle inspection reveals defects by causing leakage fields where the magnetic flux is disrupted by a flaw. Different defect orientations will disturb the flux in different ways, so using more than one magnetization direction helps reveal cracks and other flaws no matter how they lie on the surface.

Circular (circumferential) magnetization creates a field around the part’s circumference. This makes defects that run across the surface or perpendicular to the first field create leakage fields at their ends, drawing particles to those locations.

Longitudinal magnetization runs along the length of the part. Defects oriented parallel to the length will disturb the flux in a way that produces leakage along the defect, making it detectable.

Using both orientations together covers defects in multiple directions, increasing the likelihood of visibility for cracks oriented variously. Radial or nonstandard magnetization schemes aren’t typically used in routine MPI, and relying on only one direction can miss flaws that don’t align with that field.