A Differential Planar Eddy Currents Probe: Fundamentals, Modelling and Experimental Evaluation
Rosado, L. S.
; Santos, T. S.
Ramos, P. M.
; Vilaça, P.
; Piedade, M. S.
NDT and E International Vol. 51, Nº 1, pp. 85 - 93, October, 2012.
ISSN (print): 0963-8695
Journal Impact Factor: 2,225 (in 2014)
Digital Object Identifier: 10.1016/j.ndteint.2012.06.010
This paper presents a new eddy current probe specifically designed to inspect imperfections
along Friction Stir Welding joints. The proposed probe has a planar design and a differential operation
introducing several innovative aspects in eddy currents generation and sensing. The fundamentals on
the probe operation are presented and explained in the presence of a metallic part to be inspected with
and without defects. A finite element model was used to detail the probe operation and to assess the
influence of several operational parameters on the probe response. Finally, the simulations were
validated experimentally using a prototype probe produced in printed circuit board and an aluminum
alloy block with standard defects produced using electro discharge machining.