Microwave detection of corrosion under paint and composite laminate coatings

Microwave and millimeter wave nondestructive methods using open-ended sensors have shown great potential for detecting minute thickness variations in laminate structures, in particular those backed by a conducting plate, Similarly, slight variations in the composition of dielectric materials may also be detected using a set of optimal parameters which include the standoff distance sind the frequency of operation, In this paper the potential of using an open-ended rectangular waveguide for detecting the presence of ruse. (corrosion) under common paint and composite laminate coatings will be demonstrated, An experimental scanned image of a steel specimen with an area of induced corrosion will also be shown.