Detection of fatigue crack propagation through damage characteristic FWHM using FBG sensors
ISSN: 0260-2288
Article publication date: 25 October 2020
Issue publication date: 19 November 2020
Abstract
Purpose
Crack damage detection for aluminum alloy materials using fiber Bragg Grating (FBG) sensor is a kind of structure health monitoring. In this paper, the damage index of full width at half maximum (FWHM) was extracted from the distorted reflection spectra caused by the crack-tip inhomogeneous strain field, so as to explain the crack propagation behaviors.
Design/methodology/approach
The FWHM variations were also investigated through combining the theoretical calculations with simulation and experimental analyses. The transfer matrix algorithm was developed to explore the mechanism by which FWHM changed with the linear and quadratic strain. Moreover, the crack-tip inhomogeneous strain field on the specimen surface was computed according to the digital image correlation measurement during the experiments.
Findings
The experimental results demonstrated that the saltation points in FWHM curve accorded with the moments of crack propagation to FBG sensors.
Originality/value
The interpretation of reflected spectrum deformation mechanism with crack propagation was analyzed based on both simulations and experiments, and then the performance of potential damage features – FWHM were proposed and evaluated. According to the correlation between the damage characteristic and the crack-tip location, the crack-tip of the specimen could be measured rapidly and accurately with this technique.
Keywords
Acknowledgements
The authors thanked the editor and anonymous referees for their constructive comments and recommendations. This work was supported by the Technical foundation program (grant JSZL2017601C002) from the Ministry of Industry and Information Technology of the People’s Republic of China.
Citation
Zhang, M., Zhang, W., Liang, X., Zhao, Y. and Dai, W. (2020), "Detection of fatigue crack propagation through damage characteristic FWHM using FBG sensors", Sensor Review, Vol. 40 No. 6, pp. 665-673. https://doi.org/10.1108/SR-03-2020-0056
Publisher
:Emerald Publishing Limited
Copyright © 2020, Emerald Publishing Limited