Nondestructive Testing of a Complex Aluminium-CFRP Hybrid Structure with EMAT and Thermography

  • Michael SchwarzEmail author
  • Mathias Schwarz
  • Simon Herter
  • Hans-Georg Herrmann


A new concept of an aluminium-CFRP (carbon-fibre-reinforced-polymer) hybrid structure with integrated thermoplastic layer is introduced in this work. The occurring interfaces between the three materials are characterised with flash thermography and ultrasonic testing with electromagnetic acoustic transducer (EMAT). Thermography is able to detect artificial integrated defects in inner layers of the CFRP component and to characterise the bonding quality of the interface between the CFRP and the thermoplastic layer. Additionally a POD model (probability of detection) provides the smallest detectable size a90/95 of gapping defects in the CFRP with 5.184 mm diameter. This work shows that a characterisation of the deeper interface between the aluminium and the thermoplastic layer is possible despite the small and complex geometry. Furthermore the quality of this bonding can be investigated independently of the EMAT’s position. By combining thermography and EMAT the whole complex hybrid structure with its interfaces can be characterised.


Composite materials EMAT Interface Metal-CFRP-hybrid POD Thermography 



The authors gratefully acknowledge the funding by Deutsche Forschungsgemeinschaft (Grant No. HE 7079/1-2) and also thank their colleagues from Fraunhofer IZFP Saarbrücken and their research partners from wbk at Karlsruhe Institute of Technology and LKT at TU Dortmund.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Chair of Lightweight SystemsSaarland UniversitySaarbrückenGermany
  2. 2.Fraunhofer Institute for Nondestructive TestingSaarbrückenGermany

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