Share Email Print
cover

Proceedings Paper

Characterising fatigue crack in an aluminium plate using guided elastic waves
Author(s): Chao Zhou; Zhongqing Su; Li Cheng
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Integrity of in-service engineering structures is prone to fatigue damage over their lifespan. Majority of the currently existing elastic-wave-based damage identification techniques have been developed and validated for damage at macroscopic levels, by canvassing linear properties of elastic waves such as attenuation, transmission, reflection and mode conversion. However the real damage in engineering structures often initiates from fatigue crack, presenting highly nonlinear characteristics under cyclic loads. It is of great significance but vast challenge to detect fatigue damage of small dimension at its initial stage. In this study, traditional elastic-wave-based damage identification techniques were first employed with an attempt to detect fatigue crack initiated from a notch in an aluminium plate with the assistance of a signal correlation analysis, to observe the deficiency of the approach. Then the higher-order harmonic wave generation was used to exploit the nonlinear characteristics of acousto-ultrasonic waves (Lamb waves), whereby the fatigue damage was characterised. Results show that nonlinear characteristics of acousto-ultrasonic waves can facilitate more effective detection of fatigue damage than linear signal features such as wave reflection, transmission or mode conversion.

Paper Details

Date Published: 14 April 2011
PDF: 7 pages
Proc. SPIE 7981, Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2011, 798134 (14 April 2011); doi: 10.1117/12.879894
Show Author Affiliations
Chao Zhou, The Hong Kong Polytechnic Univ. (Hong Kong, China)
Zhongqing Su, The Hong Kong Polytechnic Univ. (Hong Kong, China)
Li Cheng, The Hong Kong Polytechnic Univ. (Hong Kong, China)


Published in SPIE Proceedings Vol. 7981:
Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems 2011
Masayoshi Tomizuka, Editor(s)

© SPIE. Terms of Use
Back to Top