This proposal outlines the development of a wireless Evanescent Microwave Probe (EMP) NDE technique that 1) can detect corrosion on aluminum surfaces at the 100 micron size scale, even below layers of paint, 2) can provide information on the integrity and stability of adhesive bonded patches, 3) can detect minute changes in the metal-patch bondline such as bondline separation and changes in the ambient moisture under the patch and 4) carry out these critical NDE functions in a wireless (ie. remote) operation. In previous AFRL sponsored research, this EMP NDE technique has been used to detect the existence of corrosion pits under painted aircraft wing panels and cracks beneath an adhesive bonded repair patch applied to an aircraft aluminum skin panel. In addition, this EMP NDE system has been used to detect the presence of so-called "kissing bonds" at a metal-epoxy bondline of an otherwise sound epoxy-metal bonded structure. Being able to detect corrosion in aging aircrafts while they are in the field when the crack are the size of 100 microns or smaller.
Keywords: Evanescent, Corrosion, Detection , Microwave, Probe Scanner, Surfaces
