Feasibility and limitations of damage identification in composite materials using acoustic emission

Understanding the failure mechanisms in textile composites based on acoustic emission signals is a challenging task. In the present work, unsupervised cluster analysis is performed on the acoustic emission data registered during tensile tests on two-dimensional and three-dimensional woven carbon fiber/epoxy composites. The analysis is based on the k-meansþ þ algorithm and principal component analysis. Peak amplitude and frequency features -peak frequency for two-dimensional woven composites and frequency centroid for three-dimensional woven composites -were found to be dominant in cluster analysis. Cluster bounds were identified for both reinforcement types. These bounds do not differ for both reinforcement types and can be used as a starting point for acoustic emission analysis of other carbon fiber/ epoxy composites. The statistics of high-frequency acoustic emission events are compared with the estimates obtained from a fiber bundle model based on Weibull fiber strength statistics. The number of acoustic emission events agrees well with the number of groups of carbon fibers that fail simultaneously. This finding may provide a new way to explain why the Weibull distribution predicts much more fiber breaks than measured by acoustic emission.

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“…In a recent paper, 22 these effects are investigated in detail and will be an important component of AE analysis in the future work.…”

Section: Introductionmentioning

confidence: 99%

Cluster analysis of acoustic emission signals for 2D and 3D woven carbon fiber/epoxy composites

Swolfs

Straumit

et al. 2015

Journal of Composite Materials

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“…The technique is based on the registration of acoustic signals generated by propagation of cracks and other phenomena within the material. Although it is used with metallic and composite materials, very little work has been published on its application with polymers. To best of our knowledge, no use of acoustic emission was done during the analysis of the mechanical properties of photo‐degraded polymers, which represents an important gap in the literature.…”

Section: Introductionmentioning

confidence: 99%

Use of acoustic emission in the analysis of polypropylene failure caused by photodegradation

Silva

Nunes

Rabello

2018

J of Applied Polymer Sci

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Photodegradation is among the most frequent causes for the low performance of polypropylene (PP) products during service. This type of failure has been investigated extensively throughout the years using conventional methods including infrared spectroscopy and molar mass measurements. The use of acoustic emission, conversely, is not a common technique to evaluate polymer behavior, even though showed to be very useful to detect and locate damage during loading, contributing to the understanding and, hence, to the prevention of failure. In this investigation, injection molded tensile bars were exposed to the ultraviolet radiation in the laboratory for periods of up to 35 weeks and then characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, tensile properties, and scanning electron microscopy. During tensile testing, the acoustic emission technique was applied to monitor parameters like intensity of hits, events, and energy released during deformation. The results confirmed the high efficiency of hindered amines light stabilizers to inhibit chemical degradation of PP and the high sensitivity of the neat polymer toward UV exposure. The several steps of polymer failure were detected by acoustic emission, being a very important tool to understand the differences in mechanical behavior of the types of samples under investigation. It showed the beginning of the failure process as well as significant events that occurred during the test, such as the formation of shear bands, cracking, and material fracture. These observations, combined with the traditional degradation monitoring procedures, allowed a good understanding of the effect of UV radiation on PP failure mechanism. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46943.

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“…Additionally, to visualize the modal composition of the AE signals the Choi-Williams transformation is calculated using the software package AGU-Vallen Wavelet [26]. The signals obtained through FE simulation are transformed and the result is shown in Fig.…”

Section: Experiments On C/sic Platementioning

confidence: 99%

“…Numerous publications have proposed methods for the identification of damage modes in composites using acoustic emission but they fail to address the effects of propagation characteristic such as energy attenuation on AE signal features and how those may affect the ability to differentiate between damage modes. Additionally, the propagation characteristics of AE wave in C/SiC composite is considerably complex because of the anisotropy and internal structure, which is a main drawback of the AE technique in composite structures damage detection [24][25][26][27].…”

Section: Introductionmentioning

confidence: 99%

Simulation and feature analysis of modal acoustic emission wave in planar C/SiC composite

Gao¹,

Xiao²

2018

J. vibroeng.

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A catastrophic accident may be caused for nearby spacecraft due to the damage occurred in C/SiC thermal protection structure. Therefore, it is significant to analyze the damage feature of the ceramic composite structure. Acoustic emission (AE) is an effective non-destructive testing method which is widely used in aerospace industry. However, some key problems should be solved when the AE technology applied to the engineering field. In this paper some propagation characteristics of AE waves in C/SiC plate were investigated based on the finite element method. Firstly, two kinds of AE sources were established by combining plate wave theory and finite element method. Secondly, a novel simulation model was established which included the mechanical characters of C/SiC composite. Then to simulate the AE source, a stepped load and a dipole force is applied to generate the release of power loss. Additionally, the results of simulation are validated through the AE experiment with the analysis method of Choi-Williams transformation. Finally, the attenuation of AE signals propagation in C/SiC plate is discussed. The results of this research work demonstrated that the simulation method of AE waves in C/SiC structure proposed in this paper can be effectively used to study the wave propagation phenomenon

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Feasibility and limitations of damage identification in composite materials using acoustic emission

Cited by 118 publications

References 13 publications

Cluster analysis of acoustic emission signals for 2D and 3D woven carbon fiber/epoxy composites

Cluster analysis of acoustic emission signals for 2D and 3D woven carbon fiber/epoxy composites

Use of acoustic emission in the analysis of polypropylene failure caused by photodegradation

Simulation and feature analysis of modal acoustic emission wave in planar C/SiC composite

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