Detection of early stage damage in carbon fiber reinforced

We present an experimental characterization of multidirectional fibre composites based on eddy current testing using HTS dc SQUID (Superconducting Quantum Interference Device) magnetometers. The correlation between the mechanical tolerance of CFRPs with different thickness and the phase gradient of the magnetic field generated by damage is shown. The eddy current based SQUID NDE is used to detect damage not visible to the naked eye and to study the effect of an impact far from the point of impact. The aim of this work is to demonstrate the capability of our technique to provide information on early stage damage due to an impact process in an unshielded environment.