Eddy current testing in CFRP production
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Eddy current testing has established itself as a nondestructive test method in CFRP production. By exploiting the electrical conductivity of carbon fibers, it is possible to detect fiber orientation, surface weight, area density and fiber volume content as well as ripples and folds in stacks, preforms and composite components. This article presents recent applications and discusses future perspectives for deployment in CFRP production.
Forming Multi-layer Semifinished Products
Nondestructive testing of multi-layer stacks, preforms and composite components for correct fiber orientation and freedom from defects is a recurrent task in CFRP production. The shearing of textile materials that results when flat semifinished products are draped into multi-curved 3-D geometries, changes local fiber orientation and hence the rigidity of the composite components. What is more, areas with extreme shearing also increase fiber volume content and are prone to the formation of folds and dry spots that...
The work on 3-D fiber orientation detection described here is part of the “3-D Fast” project that is funded by the European Regional Development Fund (ERDF) and the Free State of Saxony (funding code 100224749). The authors would like to thank the aforementioned institutions for the provision of financial resources. Parts of the findings represented here are based on work performed by Martin Schulze and Matthias Pooch (Fraunhofer IKTS) and Matthias Hübner and Andreas Nocke (TU Dresden), whom the authors wish to thank for kindly making them available.
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