Magnetic Particle Inspection Level 2 Practice Exam

Which type of magnetization retains the most objectionable residual field if not demagnetized?

1. Longitudinal

2. Circular

3. Vectored

4. Remnant

The correct answer is: Longitudinal

Longitudinal magnetization is characterized by the magnetic lines of force running parallel to the axis of the part being inspected. This type of magnetization can sometimes lead to significant residual magnetism after inspection. When the magnetic field is applied longitudinally, any flaws or discontinuities that are oriented along the length of the part can effectively trap magnetic particles, revealing crucial information about the integrity of the material. However, one of the downsides to longitudinal magnetization is that, if the part is not properly demagnetized after inspection, it may retain a residual magnetic field. This residual magnetism can interfere with further inspections, other operations, or even affect the performance of the component in its application. Varying levels of residual fields exist in all types of magnetization, but longitudinal magnetization typically produces a more substantial residual field, making it essential to apply proper demagnetization techniques post-inspection to mitigate potential issues.