Multivariable analysis and wavelet transform of acoustic emission data for damage analysis of composite materials

Cost-effective and reliable damage detection is critical for the utilization of composite materials due to the relatively localised nature of damage formation and the resultant reduction in structural integrity. Of the methods available, Acoustic Emission (AE) is considered as one potential technology for on-line and in situ monitoring of structural degradation of composite materials. Purpose of this work was to study the interaction between embedded PVDF (polyvinylidene fluoride) transducers and composite samples as well as detect and characterize the failure mechanisms in aramid/epoxy flexural test specimens using acoustic emission data obtained by embedded PVDF film sensors. Furthermore, it has been realized a comparison with surface mounted PVDF data. Results of our previous works (Caneva et al., 2005) dealing with monitoring tensile and flexural behaviour of glass/epoxy composites enabled to extend this methodology to aramid/epoxy composites. The use of Acoustic Emission and Scanning Electron Microscopy (SEM) observations enabled to identify and understand the failure mechanisms of the composites tested. Furthermore, satisfactory results of this work highlighted that the application of PVDF shows promise as a suitable acoustic emission transducer for fibrous composite materials.

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Fatigue damage characterization of carbon fiber reinforced polymer bridge cables: Wavelet transform analysis for clustering acoustic emission data

Science China Technological Sciences ◽

10.1007/s11431-010-4198-7 ◽

2011 ◽

Vol 54 (2) ◽

pp. 379-387 ◽

Cited By ~ 11

Author(s):

DongSheng Li ◽

Qian Hu ◽

JinPing Ou ◽

Hui Li

Keyword(s):

Acoustic Emission ◽

Wavelet Transform ◽

Carbon Fiber ◽

Fiber Reinforced Polymer ◽

Carbon Fiber Reinforced Polymer ◽

Emission Data ◽

Reinforced Polymer ◽

Damage Characterization ◽

Wavelet Transform Analysis

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Acoustic Emission and K-S Metric Entropy as Methods for Determining Mechanical Properties of Composite Materials

Sensors ◽

10.3390/s21010145 ◽

2020 ◽

Vol 21 (1) ◽

pp. 145

Author(s):

Lesław Kyzioł ◽

Katarzyna Panasiuk ◽

Grzegorz Hajdukiewicz ◽

Krzysztof Dudzik

Keyword(s):

Mechanical Properties ◽

Acoustic Emission ◽

Composite Material ◽

Composite Materials ◽

Testing Machine ◽

Measurement Data ◽

Entropy Method ◽

Displacement Sensor ◽

Metric Entropy ◽

Plastic Phase

Due to the unique properties of polymer composites, these materials are used in many industries, including shipbuilding (hulls of boats, yachts, motorboats, cutters, ship and cooling doors, pontoons and floats, torpedo tubes and missiles, protective shields, antenna masts, radar shields, and antennas, etc.). Modern measurement methods and tools allow to determine the properties of the composite material, already during its design. The article presents the use of the method of acoustic emission and Kolmogorov-Sinai (K-S) metric entropy to determine the mechanical properties of composites. The tested materials were polyester-glass laminate without additives and with a 10% content of polyester-glass waste. The changes taking place in the composite material during loading were visualized using a piezoelectric sensor used in the acoustic emission method. Thanks to the analysis of the RMS parameter (root mean square of the acoustic emission signal), it is possible to determine the range of stresses at which significant changes occur in the material in terms of its use as a construction material. In the K-S entropy method, an important measuring tool is the extensometer, namely the displacement sensor built into it. The results obtained during the static tensile test with the use of an extensometer allow them to be used to calculate the K-S metric entropy. Many materials, including composite materials, do not have a yield point. In principle, there are no methods for determining the transition of a material from elastic to plastic phase. The authors showed that, with the use of a modern testing machine and very high-quality instrumentation to record measurement data using the Kolmogorov-Sinai (K-S) metric entropy method and the acoustic emission (AE) method, it is possible to determine the material transition from elastic to plastic phase. Determining the yield strength of composite materials is extremely important information when designing a structure.

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