A hybrid method based upon nonlinear Lamb wave response for locating a delamination in composite laminates

• Published in: Ultrasonics Vol. 70; pp. 12 - 17
• Main Authors: Yelve, Nitesh P., Mitra, Mira, Mujumdar, P.M., Ramadas, C.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.08.2016
• Subjects: BVID; Carbon fiber reinforced plastics; Damage detection; Delaminating; Delamination; Hybrid method; Lamb waves; Laminates; Locating damage; Nonlinear Lamb waves; Nonlinearity; Spectra; Temporal and spectral response; BVID; Locating damage; Temporal and spectral response; Nonlinear Lamb waves; Hybrid method; Delamination
• ISSN: 0041-624X; 1874-9968
• DOI: 10.1016/j.ultras.2016.04.012

•A new hybrid method is introduced to locate a delamination in composite laminates.•The experimental case considered mimic a practical application very closely.•The method does not need information from the pristine specimen.•The method uses only eight piezoelectric wafer transducers thus quite economical.•The method can detect any breathing damage which can induce contact nonlinearity. A new hybrid method based upon nonlinear Lamb wave response in time and frequency domains is introduced to locate a delamination in composite laminates. In Lamb wave based nonlinear method, the presence of damage is shown by the appearance of higher harmonics in the Lamb wave response. The proposed method not only uses this spectral information but also the corresponding temporal response data, for locating the delamination. Thus, the method is termed as a hybrid method. The paper includes formulation of the method and its application to locate a Barely Visible Impact Damage (BVID) induced delamination in a Carbon Fiber Reinforced Polymer (CFRP) laminate. The method gives the damage location fairly well. It is a baseline free method, as it does not need data from the pristine specimen.