A new electromagnetic NDI-technique based on the measurement of source-sample reaction forces

• Published in: AIP Conference Proceedings pp. 361 - 368
• Main Authors: Fitzpatrick, G L, Skaugset, R L, Shih, W C L
• Format: Conference Proceeding
• Language: English
• Published: 01.01.2000
• ISSN: 0094-243X

Faraday's law of induction, Lenz's law, the Lorentz force law and Newton's third law, taken together, insure that sources (e.g., coil sources) of time-dependent electromagnetic fields, and nearby "nonmagnetic" electrical conductors (e.g., aluminum), always experience mutually repulsive (source-conductor) forces. This fact forms the basis for a new method for detecting cracks and corrosion in (aging) multi-layer airframes. The presence of cracks or corrosion (e.g., material thinning) in these structures is observed to reduce (second-harmonic) source-conductor reaction forces. (Author)