Estimation of remaining useful life of fatigued plate specimens using Lamb wave‐based nonlinearity parameters

Abstract

Summary The present study focuses on estimating material nonlinearity and consequently remaining useful life of fatigued specimens using the amplitude‐ and physics‐based material nonlinearity parameters evaluated for Lamb wave motion in plate specimens. The amplitude‐based nonlinearity parameter depends on amplitudes of the Lamb wave harmonics generated due to material nonlinearity. Here, it is employed to estimate the inherent and dislocation induced material nonlinearities for different stages of fatigue. The cumulative effect is obtained from the strict matching of phase and group velocities of the S1 − S2 mode pair. The physics‐based nonlinearity parameter is obtained from the higher order elastic coefficients, plastic coefficients, and substructural evolution parameters. It does not depend on wave propagation distance; however, it depends on percent fatigue life. Thus, it is used to construct a theoretical nonlinearity curve. A spectral amplitude normalization technique is given to systematically evaluate the material nonlinearity, once the Lamb wave data over different wave propagation distances are known either from experiments or from simulations. The values of amplitude‐based nonlinearity parameter thus estimated through the simulation and experiments for different fatigue stages are then plotted onto the obtained theoretical nonlinearity curve. A reasonably good agreement is seen between the fatigue life estimations given by both the nonlinearity parameters. Thus, the amplitude‐based nonlinearity parameter obtained from the Lamb wave response can be effectively used to estimate the remaining useful life of the fatigued plate specimens.

Detection and characterization of matrix cracking in fiber‐metal laminates using Lamb wave propagation

“…The application of guided wave propagation, especially the Lamb waves that are widely used for the evaluation of plate-like structures, has been dramatically increased. [16][17][18][19][20][21] The term guided wave is used to represent the waves that require a structural boundary to propagate. These waves have a limited number of propagation modes and are sensitive to damage and changes in the mechanical properties of materials.…”

“…The application of guided wave propagation, especially the Lamb waves that are widely used for the evaluation of plate‐like structures, has been dramatically increased 16–21 . The term guided wave is used to represent the waves that require a structural boundary to propagate.…”

Analytical computation of the dominant dispersion trend of Lamb waves in plate‐like structures with an improved dynamic stiffness matrix method

“…The excitation on a structure does not necessarily generate all dispersion modes, and often, there is a single dominant mode at each frequency, 5,24,27–29 hereinafter referred to as the “apparent dispersion trend.” The use of “apparent dispersion trend” does not deny the possible existence of the other modes at a certain frequency; however, these modes have less energy than the dominant mode. Multimodal experimental dispersion data can be found in some studies 30–34 ; however, the multimodal data are generally incomplete in the frequency range of interest and are unclear at some frequencies. Different modes have different levels of excitability, and excitability is the extent to which a mode is generated when a specified excitation is applied 35,36 .…”

Numerical and experimental research on damage shape recognition of aluminum alloy plate based on Lamb wave

“…Meanwhile, Hameed et al (2019) and Zheng et al (2019) introduced a multistage damage detection method to locate the damage and determine the area size of the damage. Tse et al (2020) estimated the remaining useful life of the fatigued plate specimens by the amplitude obtained from the Lamb wave. Andhale et al (2019) proposed a algorithm to localize the faulty rivet using the spectral content information from Lamb wave.…”