Abstract
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.
Similar content being viewed by others
References
Verkehrsclub Deutschland. CO2 emissions in automotive, https://www.vcd.org/themen/auto-umwelt/co2-grenzwert/ (2017). Accessed 28 Feb 18
Summa, J., Schwarz, M., Herrmann, H.G.: Evaluating the Severity of defects in a metal to CFRP hybrid-joint with in situ passive thermography damage monitoring. In: Proceedings 5th International Conference on Integrity, Reliability & Failure, IRF Porto, pp. 117–126 (2016)
Park, H., Choi, M., Park, J., Kim, W.: A study on detection of micro-cracks in the dissimilar metal weld through ultrasound infrared thermography. Infrared Phys. Technol. 62, 124–131 (2014)
Schroeder, J.A., Ahmed, T., Chaudry, B., Shepard, S.: Non-destructive testing of structural composites and adhesively bonded composite joints: pulsed thermography. Composites A 33, 1511–1517 (2002)
Maierhofer, C., Myrach, P., Reischel, M., Steinfurth, H., Röllig, M., Kunert, M.: Characterizing damage in CFRP structures using flash thermography in reflection and transmission configurations. Composites B 57, 35–46 (2014)
Meola, C.: Infrared Thermography: Recent Advances and Future Trends. Bentham Science, New York (2012)
Howell, J.R., Pinar, M.M., Robert, S.: Thermal Radiation Heat Transfer, vol. 5. Taylor & Francis, New York (2010)
Maldague, X.P.V.: Theory and Practice of Infrared Technology for Nondestructive Testing, pp. 15–32. Wiley & Sons Inc, New York (2001)
Schwarz, M., Summa, J., Herrmann, H.G.: Characterizing metal—CFRP hybrid structures by nondestructive testing methods. In: Proceedings 5th International Conference on Integrity, Reliability & Failure, IRF Porto, pp. 127–136 (2016)
Thermosensorik: Operating Manual—Infrared Camera Head QWIP 384 Dualband (2009)
Jian, X., Dixon, S., Edwards, R.S., Reed, J.: Coupling mechanism of electromagnetic acoustical transducers for ultrasonic generation. J. Acoust. Soc. Am. 119(5), 2693–2701 (2006)
Salzburger, H.J., Niese, F., Dobmann, G.: EMAT pipe inspection with guided waves. Weld. World 56, 35–43 (2012)
Luo, W., Rose, J.L.: Guided wave thickness measurement with EMATs. Insight-Non-Destr. Test. Cond. Monit. 45(11), 735–739 (2003)
Petcher, P.A., Potter, M.D.G., Dixon, S.: A new electromagnetic acoustic transducer (EMAT) design for operation on rail. NDT&E Int. 65, 1–7 (2014)
Petcher, P.A., Dixon, S.: Weld defect detection using PPM EMAT generated shear horizontal ultrasound. NDT&E Int. 74, 58–65 (2015)
Le Crom, B., Castaings, M.: Shear horizontal guided wave modes to infer the shear stiffness of adhesive bond layers. Acoust. Soc. Am. 127(4), 2220–2230 (2010)
Arun, K., Dhayalan, R., Balasubramaniam, K., Maxfield, B., Peres, P., Barnoncel, D.: An EMAT-based shear horizontal (SH) wave technique for adhesive bond inspection. AIP Conf. Proc. 1430(1), 82–86 (2012)
Castaings, M.: SH ultrasonic guided waves for the evaluation of interfacial adhesion. Ultrasonics 54, 1760–1775 (2014)
Pérès, P., Barnoncel, D., Balasubramaniam, K., Castaings, M.: New experimental investigations of adhesive bonds with ultrasonic SH guided waves. In: 18th International Conference on Composite Materials (2011)
Gao, H., Ali, S., Lopez, B.: Efficient detection of delamination in multilayered structures using ultrasonic guided wave EMATs. NDT&E Int. 43, 316–322 (2010)
Huang, S., Wei, Z., Zhao, W., Wang, S.: A new omni-directional EMAT for ultrasonic Lamb wave tomography imaging of metallic plate defects. Sensors 14(2), 3458–3476 (2014)
Dixon, S., Edwards, C., Palmer, S.B.: Recent developments in the characterisation of aluminium sheets using electromagnetic acoustic transducers (EMATs). Insight-Non-Destr. Test. Cond. Monit. 44, 274–278 (2002)
Edwards, R.S., Dixon, S., Jian, X.: Characterisation of defects in the railhead using ultrasonic surface waves. NDT&E Int. 39, 468–475 (2006)
Edwards, R.S., Jian, X., Fan, Y., Dixon, S.: Signal enhancement of the in-plane and out-of-plane Rayleigh wave components. Appl. Phys. Lett. 87(19), 194104 (2005)
Neumann E. Ultraschallprüfung von austenitischen Plattierungen, Mischnähten und austenitischen Schweißnähten. Expertverlag, vol. 377, Chap. 5 (1995)
Annis, C., Gandossi, L., Martin, O.: Optimal sample size for probability of detection curves. Nucl. Eng. Des. 262, 98–105 (2013)
Annis, C.: Statistical best-practices for building Probability of Detection (POD) models. R package mh1823, version 4.4.8 (2016). http://StatisticalEngineering.com/mh1823/
Herter, S.: Quantitative Untersuchungen von Klebverbindungen und Hybridbauteilen mittels geführter Ultraschallwellen an geometrisch komplexen Strukturen. Universität des Saarlandes, Bachelorarbeit (2018)
Acknowledgements
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.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that they have no conflict of interest.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Schwarz, M., Schwarz, M., Herter, S. et al. Nondestructive Testing of a Complex Aluminium-CFRP Hybrid Structure with EMAT and Thermography. J Nondestruct Eval 38, 35 (2019). https://doi.org/10.1007/s10921-019-0578-5
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s10921-019-0578-5