NDT Equipment manufacturer Eddyfi Technologies have recently been granted a patent (number EP2506003A1) for their proprietary technology to map near surface discontinuities on ferrous materials through thick coatings in excess of 10 mm. Because magnetic flux leakage (MFL) signals alone are unable to reliably discriminate between near-side and far-side material loss, the complementary surface topology air-gap reluctance sensor (STARS) approach was designed to perform discrimination automatically.

Source: NDT