Immunity of the second harmonic shear horizontal waves to adhesive nonlinearity for breathing crack detection

2021 ◽  
pp. 147592172110571
Author(s):  
Fuzhen Wen ◽  
Shengbo Shan ◽  
Li Cheng
Keyword(s):  
Crack Detection ◽  
Guided Waves ◽  
Lamb Waves ◽  
Second Harmonic ◽  
Sh Waves ◽  
High Order Harmonic ◽  
Thin Walled Structures ◽  
Harmonic Shear ◽  
Contact Acoustic Nonlinearity ◽  
Shear Horizontal

High-order harmonic guided waves are sensitive to micro-scale damage in thin-walled structures, thus, conducive to its early detection. In typical autonomous structural health monitoring (SHM) systems activated by surface-bonded piezoelectric wafer transducers, adhesive nonlinearity (AN) is a non-negligible adverse nonlinear source that can overwhelm the damage-induced nonlinear signals and jeopardize the diagnosis if not adequately mitigated. This paper first establishes that the second harmonic shear horizontal (second SH) waves are immune to AN while exhibiting strong sensitivity to cracks in a plate. Capitalizing on this feature, the feasibility of using second SH waves for crack detection is investigated. Finite element (FE) simulations are conducted to shed light on the physical mechanism governing the second SH wave generation and their interaction with the contact acoustic nonlinearity (CAN). Theoretical and numerical results are validated by experiments in which the level of the AN is tactically adjusted. Results show that the commonly used second harmonic S0 (second S0) mode Lamb waves are prone to AN variation. By contrast, the second SH0 waves show high robustness to the same degree of AN changes while preserving a reasonable sensitivity to breathing cracks, demonstrating their superiority for SHM applications.

Third harmonic shear horizontal waves for material degradation monitoring

2020 ◽  
pp. 147592172093698
Author(s):  
Fuzhen Wen ◽  
Shengbo Shan ◽  
Li Cheng
Keyword(s):  
Lamb Waves ◽  
Second Harmonic ◽  
Material Degradation ◽  
Microstructural Changes ◽  
Third Harmonic ◽  
The Third ◽  
Degradation Monitoring ◽  
Mode Pair ◽  
Harmonic Shear ◽  
Shear Horizontal

Early detection of incipient damage in structures through material degradation monitoring is a challenging and important topic. Nonlinear guided waves, through their interaction with material micro-defects, allow possible detection of structural damage at its early stage of initiations. This issue is investigated using both the second harmonic Lamb waves and the third harmonic shear horizontal waves in this article. A brief analysis first highlights the selection of the primary–secondary S0 Lamb wave mode pair and primary–tertiary SH0 mode pair from the perspective of cumulative high-order harmonic wave generation. Through a tactic design, an experiment is then conducted to compare the sensitivity of the third harmonic shear horizontal waves and the second harmonic Lamb waves to microstructural changes on the same plate subjected to a dedicated thermal heating treatment. The third harmonic shear horizontal waves are finally applied to monitor the microstructural changes and material degradation in a plate subjected to a thermal aging sequence, cross-checked by Vickers hardness tests. The experiment results demonstrate that the third harmonic shear horizontal waves indeed exhibit higher sensitivity to microstructural changes than the commonly used second harmonic Lamb waves. In addition, results demonstrate that the designed third harmonic shear horizontal wave–based system entails effective characterization of thermal aging–induced microstructural changes in metallic plates.

scholarly journals Fatigue crack detection in pipes with multiple mode nonlinear guided waves

2018 ◽  
Vol 18 (1) ◽  
pp. 180-192 ◽  
Author(s):  
Ruiqi Guan ◽  
Ye Lu ◽  
Kai Wang ◽  
Zhongqing Su
Keyword(s):  
Fatigue Crack ◽  
Crack Detection ◽  
Guided Waves ◽  
Second Harmonic ◽  
Experimental Testing ◽  
Harmonic Wave ◽  
Guided Wave ◽  
Element Analysis ◽  
Fatigue Crack Detection ◽  
Wave Modes

This study elaborates fundamental differences in fatigue crack detection using nonlinear guided waves between plate and pipe structures and provides an effective approach for analysing nonlinearity in pipe structures. For this purpose, guided wave propagation and interaction with microcrack in a pipe structure, which introduced a contact acoustic nonlinearity, was analysed through a finite element analysis in which the material nonlinearity was also included. To validate the simulation results, experimental testing was performed using piezoelectric transducers to generate guided waves in a specimen with a fatigue crack. Both methods revealed that the second harmonic wave generated by the breathing behaviour of the microcrack in a pipe had multiple wave modes, unlike the plate scenario using nonlinear guided waves. Therefore, a proper index which considered all the generated wave modes due to the microcrack was developed to quantify the nonlinearity, facilitating the identification of microscale damage and further assessment of the severity of the damage in pipe structures.

scholarly journals Numerical Simulation on Micro-damage Detection In CFRP Composites Based on Nonlinear Ultrasonic Guided Waves

2021 ◽  
Keyword(s):  
Damage Detection ◽  
Composite Structures ◽  
Guided Waves ◽  
Second Harmonic ◽  
Wave Mode ◽  
Guided Wave ◽  
Reinforced Plastics ◽  
Matrix Cracks ◽  
Nonlinear Ultrasonic ◽  
Contact Acoustic Nonlinearity

Abstract. Micro-damages such as pores, closed delamination/debonding and fiber/matrix cracks in carbon fiber reinforced plastics (CFRP) are vital factors towards the performance of composite structures, which could collapse if defects are not detected in advance. Nonlinear ultrasonic technologies, especially ones involving guided waves, have drawn increasing attention for their better sensitivity to early damages than linear acoustic ones. The combination of nonlinear acoustics and guided waves technique can promisingly provide considerable accuracy and efficiency for damage assessment and materials characterization. Herein, numerical simulations in terms of finite element method are conducted to investigate the feasibility of micro-damage detection in multi-layered CFRP plates using the second harmonic generation (SHG) of asymmetric Lamb guided wave mode. Contact acoustic nonlinearity (CAN) is introduced into the constitutive model of micro-damages in composites, which leads to the distinct SHG compared with material nonlinearity. The results suggest that the generated second order harmonics due to CAN could be received and adopted for early damage evaluation without matching the phase of the primary waves.

Damage Detection Using Lamb Waves (Review)

2014 ◽  
Vol 1028 ◽  
pp. 161-166 ◽  
Author(s):  
Zai Lin Yang ◽  
Hamada M. Elgamal ◽  
Yao Wang
Keyword(s):  
Damage Detection ◽  
Health Monitoring ◽  
Guided Waves ◽  
Damage Identification ◽  
Lamb Waves ◽  
Long Distance ◽  
The Past ◽  
Thin Walled Structures ◽  
Thin Walled ◽  
Analytical Complexity

Several techniques have been researched for detecting damage in plates. Each of these techniques offers their own unique advantages in detecting certain types of damage with various levels of analytical complexity. Lamb waves are guided waves that exist in thin walled structures. Because this type of wave can travel long distance with little attenuation, they have been studied intensively for structural health monitoring, especially in the past few decades. This paper presents an overview of using the Lamb waves in damage detection including the theory of lamb waves and the lamb-wave-based damage identification.

Flaw Detection in Aluminum Plate by Shear Horizontal Guided Wave Based on Magnetostriction EMAT

2014 ◽  
Vol 614 ◽  
pp. 287-290
Author(s):  
Le Chen ◽  
Yue Min Wang ◽  
Hai Quan Geng
Keyword(s):  
Guided Waves ◽  
Flaw Detection ◽  
Test Sample ◽  
Guided Wave ◽  
Sh Waves ◽  
Electromagnetic Acoustic Transducers ◽  
Acoustic Transducers ◽  
Non Destructive ◽  
Viable Method ◽  
Shear Horizontal

Shear horizontal (SH) guided waves have been proved to be a viable method in the Non-Destructive Evaluation (NDE). Electromagnetic acoustic transducers (EMAT) can excite SH waves easily. By bonding the Fe-Co alloy to the test sample, the SH guided waves based on magnetostriction effect can be used to detect the flaw in nonferromagnetic material. The principle of exciting and receiving SH waves is introduced, and an experiment is carried out to validate the result.

scholarly journals Parametric Study of Ultrasonic De-Icing Method on a Plate with Coating

Coatings ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 631 ◽  
Author(s):  
Zhonghua Shi ◽  
Yueqing Zhao ◽  
Chengkun Ma ◽  
Jifeng Zhang
Keyword(s):  
Power Consumption ◽  
Parametric Study ◽  
Lamb Waves ◽  
Interface Shear ◽  
Sh Waves ◽  
Ultrasonic Parameters ◽  
Shear Horizontal ◽  
Selection Of ◽  
Process Material ◽  
Good Agreement

Ultrasonic de-icing is a promising method to de-ice structures by using lightweight and simple transducers, with the advantage of low power consumption. A successful ultrasonic de-icing technique requires the understanding of the effects of different parameters on de-icing. This paper presents a thorough parametric study of the ultrasonic de-icing method on a plate with coating. First, the dispersion equations of shear horizontal (SH) and Lamb waves were derived based on the global matrix method. Meanwhile, interface shear concentration coefficients (ISCC) were introduced to represent the ability of ultrasonic de-icing, which was further integrated into Lamb wave and SH waves dispersion curves for the selection of optimal frequencies. Second, a three-layer plate model (host plate-coating-ice) was used to demonstrate the effect of different parameters of coating and the thickness of ice on ultrasonic de-icing. The theoretical model provided the design principle of coating and ultrasonic parameters required for efficient de-icing. Finally, an experiment was conducted on an ultrasonic de-icing platform to validate the proposed ultrasonic de-icing method. In this process, material parameters including the Young’s modulus, thickness of coating, and thickness of the ice layer were analyzed. The trends of power consumption and optimal frequency of experiments are in good agreement with the analytical calculated results.

Third harmonic shear horizontal and Rayleigh Lamb waves in weakly nonlinear plates

2013 ◽  
Vol 114 (11) ◽  
pp. 114908 ◽  
Author(s):  
Yang Liu ◽  
Vamshi K. Chillara ◽  
Cliff J. Lissenden ◽  
Joseph L. Rose
Keyword(s):  
Lamb Waves ◽  
Weakly Nonlinear ◽  
Third Harmonic ◽  
Harmonic Shear ◽  
Shear Horizontal

scholarly journals Machine Learning Based Corrosion-like Defect Estimation with Shear-Horizontal Guided Waves Improved by Mode Separation

IEEE Access ◽  
2021 ◽  
pp. 1-1
Author(s):  
Mateus Gheorghe de Castro Ribeiro ◽  
Alan Conci Kubrusly ◽  
Helon Vicente Hultmann Ayala ◽  
Steve Dixon
Keyword(s):  
Machine Learning ◽  
Guided Waves ◽  
Mode Separation ◽  
Defect Estimation ◽  
Shear Horizontal

Inspection of Concrete-Metal Rod Interface Using Guided Waves

2000 ◽  
Author(s):  
Won-Bae Na ◽  
Tribikram Kundu ◽  
Mohammad R. Ehsani
Keyword(s):  
Lamb Wave ◽  
Guided Waves ◽  
Lamb Waves ◽  
Guided Wave ◽  
Ultrasonic Transducers ◽  
Interface Debonding ◽  
Long Distance ◽  
Steel Rebar ◽  
Steel Bars ◽  
Steel Rebars

Abstract The feasibility of detecting interface degradation and separation of steel rebars in concrete beams using Lamb waves is investigated in this paper. It is shown that Lamb waves can easily detect these defects. A special coupler between the steel rebar and ultrasonic transducers has been used to launch non-axisymmetric guided waves in the steel rebar. This investigation shows that the Lamb wave inspection technique is an efficient and effective tool for health monitoring of reinforced concrete structures because the Lamb wave can propagate a long distance along the reinforcing steel bars embedded in concrete as the guided wave and is sensitive to the interface debonding between the steel rebar and concrete.

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