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MPI

First, lets check out how this magnetic particles inspection carries out :). It's always easy to understand something practical by watching a youtube video. Theory can be found in the last article.



Another video with a more advanced MPI



This one is in Spanish, though the MPI shown very well, and the crack is well visible. MPI usually find cracks which are perpendicular to the direction of the flux, so It's necessary to search for defects twice. I'll explain more about that in a future article, but first it's important to see and understand the basic chemistry of this method.

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