Identify the material correctly

An aluminium part and many stainless alloys cannot be assumed to respond like a ferromagnetic steel part. Appearance, colour and a broad commercial description are not complete material evidence. ASNT explicitly bounds magnetic-particle testing to magnetizable materials. A quick magnet response also does not establish the alloy identity, heat treatment or the inspection settings appropriate to the component and suspected defect.

Match sensitivity and access to the concern

Discontinuity orientation, surface condition, geometry and the selected technique affect what can be revealed. A surface examination cannot exclude every deep internal defect. Coatings or inaccessible regions may limit the valid scope, and preparation must be authorized so it does not damage the component. The inspection specialist should define the method and any required post-test condition; this page supplies no magnetization or field application procedure.

If a replacement part changes from a ferromagnetic material to another alloy, an earlier inspection method may no longer apply even when the geometry matches. The material change therefore affects the condition-assessment plan as well as any mechanical compatibility review for that component.

Use the indication within its boundary

Ask what regions were adequately examined, which indications require evaluation and what concerns remain outside coverage. A negative result is not a universal certification that the part has no defect, while a visible indication is not automatically an unacceptable crack. No MARSTON material, magnetic-particle criterion or repair permission is established here. The relevant component evidence and qualified assessment must support any service or replacement decision.