The Detection of Impact Damage to the Edges of CFRP Plates Using Extensional Ultrasonic Edge Waves

Jun Yu Harry Chu, Charles R.P. Courtney

Research output: Contribution to journalArticlepeer-review

7 Citations (SciVal)


Extensional edge waves propagate along the edges of plates, with low attenuation in the propagation direction and amplitude decreasing rapidly (within one or two wavelengths) in the direction perpendicular to the plate edge. This makes them an ideal candidate for inspecting the edges of plate-like structures. Here, finite-element models and experiments are used to investigate the propagation and scattering of extensional edge waves in composite plates and application to damage detection is demonstrated. Piezoceramic transducers attached to the edge of a 4-mm-thick carbon-fibre-reinforced polymer (CFRP) plate were used to excite 140-kHz edge waves and damage detection demonstrated using two experimental configurations: pitch-catch and two-transducer pulse-echo. Damage due to edge-on impacts of 5 J and 10 J were detected in both configurations. A mass-addition damage model was used to investigate the effect of damage location. Detection was specific to damage within 33 mm (1.5 wavelengths) of the plate edge with propagation unaffected by features beyond that distance. The time of arrival of reflected signals in pulse-echo mode was accurately predicted using the edge-wave group velocity indicating that this configuration can be used for locating damage on edges. The localisation of edge waves means that they can specifically detect damage at the edges of structures, and attenuation measurements indicate that their useful propagation distance is large (5.5 m).

Original languageEnglish
Article number88
JournalJournal of Nondestructive Evaluation
Issue number4
Early online date5 Oct 2021
Publication statusPublished - 31 Dec 2021

Bibliographical note

Funding Information:
The authors gratefully acknowledge funding from the EPSRC and technical support from Tom Bertenshaw at GKN as part of the Rapid Inspection of Complex Geometries Using Edge-Guided Ultrasonic Waves project (Grant No. EP/M027724/1).


  • Edge waves
  • Guided waves
  • Health monitoring
  • Ultrasonics

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering


Dive into the research topics of 'The Detection of Impact Damage to the Edges of CFRP Plates Using Extensional Ultrasonic Edge Waves'. Together they form a unique fingerprint.

Cite this