This paper reports on Giant‐Magneto Resistance
(GMR) electronic second order gradiometer used as an EC probe to detect defects in Al‐Ti riveted multi‐layers non‐magnetic metallic samples used in aircraft structures. An electronic characterization of the GMR
gradiometer set‐up for investigating the probe performance and its magnetic field sensitivity is presented. The comparison between magnetic images obtained by GMR probes and conventional excitation coils demonstrates the possibility to use successfully GMR technology as sensors for NDT applications.