Defects Characterization in CFRP Materials Industrial and Civil Applications

The process of production of carbon fiber reinforced polymers, is very elaborate and un-free from faults and problems. Problems during the manufacturing, such as inclusion of other materials, can cause °aws in the resulting material, this way compromising its integrity. Reliable performance of a component or structure depends on its pre-service quality and in- service degradation under operating conditions. The importance of Non-Destructive Testing and Evaluation is ever increasing, above all in ensuring pre-service quality and monitoring in- service degradation, in order to avoid premature failure of the components/structures in carbon ¯ber reinforced polymers for industrial and civil applications. Within this framework, this work aims to propose a design of a new eddy current probe for non destructive evaluation, based on a ferrite core probe, in order to investigate the presence of defects in carbon ¯ber epoxy composite materials such as delaminations or inclusions [1]. Particularly, in this work we propose a Finite Element Method based approach for modelling a fast and accurate evaluation of defects in composite materials able to easily detect defects, aside from the orientation. The e®ect of the ferrite core is analyzed in order to focus magnetic °ux density on the investigated specimen. Eddy currents generated by high speed ferrite core probe movement were investigated by using numerical simulation. Particularly, Finite Element Approach has been exploited in order to emphasize the presence of defects in a multi-layer carbon ¯ber epoxy structure. Proposing an high speed inspection system, that involves probe optimization, the extraction of features from FEA signals and defect characterization using signal processing techniques and Soft Compunting techniques for inverse problem solution.