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1

Application of the Acoustic Emission Technique for Damage Identification in the Fiber Reinforced Polymer Composites

Samborski Sylwester, Korzec Izabela

Advances in Science and Technology. Research Journal

|

2023

|

Vol. 17, no 1

210--221

EN

A set of experiments having in target determination of fracture resistance was performed on the Fiber Reinforced Polymer (FRP) composites specimens with an additional monitoring of damage onset and evolution with a so-called Acoustic Emission (AE) technique. The AE technique is a non-destructive material testing method, which enables registering the phenomena usually not audible with a human ear - the frequency bands lay between 100 and 1000kHz. For the FRP composites this enables monitoring various damage phenomena - matrix cracking, delamination, fiber cracking etc. by acquisition and subsequent analysis of several AE parameters: number of hits, number of counts, amplitude or energy of the signal. In the paper advantages of a deeper analysis of the raw AE signal was presented with an application of the Fast Fourier Transform (FFT), leading to a more detailed damage identification along the whole loading procedure. The study proved the usability of the AE method in damage monitoring of the FRPs; a bundle of illustrative examples of chosen acoustic emission parameters’ evolution displayed on the background of the load applied to composite specimens was presented and interpreted.

2

Comparison of Acoustic Emission Data Acquired During Tensile Deformation of Maraging Steel M250 Welded Specimens

Wuriti Gowri Shankar, Chattopadhyaya Somnath, Krolczyk Grzegorz

Archives of Acoustics

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2020

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Vol. 45, No. 2

221--231

EN

Safety and reliability are primary concerns in launch vehicle performance due to the involved costs and risk. Pressure vessels are one of the significant subsystems of launch vehicles. In order to have minimal weight, high strength material viz. maraging steel M250 grade is used in realizing the pressure vessel casing hardware. Despite the best efforts in design methodology, quality evaluation in production and effective structural integrity assessment is still a farfetched goal. The evolution of such a system requires, first, identification of an appropriate technique and next its adoption to meet the challenges posed by advanced materials like maraging steels. In fact, a quick survey of the available Non-Destructive Evaluation (NDE) techniques suggests Acoustic Emission (AE) as an effective structural integrity assessment tool capable of identifying any impending failure or degradation at an earlier stage. Experience shows that the longitudinal welds in the pressure vessels are quite vulnerable to failure due to the fact that they experience the maximum stress (i.e. hoop stress). Loading welded tensile samples are quite synonymous to the hoop stress experienced by longitudinal welds. An attempt is made to compare the Acoustic Emission data acquired during tensile deformation of maraging steel welded specimens. A total of 16 welded specimen’s with known defects were studied for their tensile behaviour is in connection with Acoustic Emission data. The lowest failure load was 70.5 kN and the highest being 84.8 kN. AE activity graphs viz. cumulative AE activity, hit rate, energy rate, count rate, AE amplitude history, AE count history, AE energy history, amplitude-count correlation and hit amplitude distribution have been investigated and salient features with respect to the data have been critically studied and relevant correlations are arrived at.

3

The possibility of applying acoustic emission method for monitoring lathing process

Dudzik Krzysztof

Journal of KONES

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2019

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Vol. 26, No. 2

21--27

EN

Nowadays acoustic emission (AE) method is used in many fields of science, including in the diagnosis and monitoring of machining processes such as turning, grinding, milling, etc. Monitoring of turning process allows ensuring stable conditions of treatment. Stable conditions of turning process have a great impact on the quality of the surface. This is especially important during finishing treatment. The research was carried out on a universal ZMM-SLIVEN CU500MRD lathe centre-using tool with removable insert SANDVIK Coromant WNMG 080408 – WMX Wiper. Lathing process was performed on the shaft of 74 mm in diameter made of S235 steel. The research was carried out at constant cutting speed v = 230 m/min. Changed parameters were feed f = 0.1; 0.2; 0.4 mm/rev and cutting depth ap = 0.5; 0.75; 1 mm. In the research was used a set of acoustic emission Vallen System. The kit includes: 4 channel signal recorder AMSY 6, two measurement modules ASIP-2/S, preamplifier with a frequency range 20 kHz – 1 MHz and the strengthening of 34dB and AE signal measurement sensor type VS 150M, with a frequency range 100 – 450 kHz. During the study, the acoustic emission (AE) generated during the lathing process were recorded parameters e.g. amplitude, number of events – hits, the effective value of the signal (RMS). The test results indicate, that the higher instability of the process was during turning with parameters: ap = 0.75 mm and f = 0.1 mm/rev. The study can be the basis for the use of acoustic emission method for monitoring lathing process to ensure stable conditions of that process and the same to obtain a high quality surface.

4

The possibility of application of the acoustic emission method for monitoring friction processes

Dudzik K., Ziegler B.

Journal of KONES

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2018

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Vol. 25, No. 2

113--119

EN

This article presents the methodology and research results of monitoring friction processes between couple of cooperating elements by acoustic emission method. The research was carried out at the lathing machine test stand of the Technische Hochschule Mittelhessen. The test stand included lathing machine Proxon PD 210, shaft, made of austenitic stainless steel X2CrNi18-9 and steel plate, made of S235. The Friction process was monitored by an acoustic emission set made by Physical Acoustics Corporation (PAC). The PAC system includes: preamplifier USB AE Node, type 1283 with bandpass 20 kHz – 1 MHz, AE signal measurement sensor type VS 150M, with a frequency range 100-450 kHz, computer with AE Win for USB Version E5.30 software. During the study, the acoustic emission (AE) generated by friction between shaft and steel plate was recorded. The load of the plate was 0, 1, 2, 3, 4, 5 and 10 N. The following parameters were determined: amplitude, number of events – hits, the effective value of the signal (RMS). The use of grease between the cooperating elements caused a significant reduction in friction and thus the power of the generated signal (10 to 30 times). In the case of dry friction, without grease, the maximum RMS value was recorded at 4 N load and at the lubricant between the pair cooperating at 1 N load. The research has shown that it is possible to monitor the friction process between cooperating elements using the acoustic emission method.

5

Tensile Damage Mechanism of 3-D Angle-Interlock Woven Composite using Acoustic Emission Events Monitoring

Ma Q., Wang K., Wang S. D., Liu H., Jin B. C., Jin L. M., Ma P.

Autex Research Journal

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2018

|

Vol. 18, no. 1

46--50

EN

The quasi-static tensile damage behavior of one type of layer-to-layer 3-Dimensional Angle-interlock Woven Composite (3DAWC) was tested and analyzed in this paper. Incorporated with the acoustic emission (AE) events monitoring, the mechanical behavior of the 3DAWC under tensile loading condition was characterized. The Load-Extension curve, Load/AE events-Time curves occurred during the entire testing process and tensile damage modes were recorded to characterize and summarize the mechanical properties and damage mechanism of the 3DAWC subjected to tensile loading. It was found that the tensile damage of the 3DAWC could be summarized into 3 steps. And each step has a distinct primary damage mode. Moreover, the resin cracks, resin-yarn interface debonding and yarn breakages were the main damage modes for the 3DAWC.

6

Study of Modified Aluminous Porcelain Subjected to Mechanoacoustic Tests

Ranachowski P., Ranachowski Z., Wieczorek K., Jaroszewski M., Kudela S. jr.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 4

1821--1826

EN

The paper presents the microscopic and mechanoacoustic study of degradation processes of the porcelain material C 130 type. This kind of material is used in the production of the most durable and reliable electrotechnical elements. Raw material composition of the studied porcelain was modified. This had an impact on the inner properties, cohesion and – in consequence – on operational properties of the material. Using mechanical-acoustic and microscopic methods of testing of small-size samples that were subjected to compression, it was possible to distinguish successive stages of degradation of the porcelain structure. These stages were generally typical of the porcelain materials. In the authors’ opinion, they are connected to the ageing process happening over many years of work under operating conditions. Optimization of composition and technological properties – important during technological processes – resulted in a slight decrease in inner cohesion of the porcelain. When compared to the reference material – typical domestic C 130 material, mechanical strength was somewhat lower. Carried out investigations proved that resistance of the investigated material to the ageing degradation process – during long term operation – also decreased. The improvement of technological parameters and the reduction in the number of defective elements occurred simultaneously with some decrease in the operational parameters of the material. To restore their initial high level, further work is needed to optimize the raw material composition of the porcelain.

7

The possibility of application the acoustic emission method for monitoring flow of water within a ball valve

Dudzik K., Ziegler B.

Journal of KONES

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2016

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Vol. 23, No. 4

87--92

EN

Acoustic emission method (AE) can be used for the diagnosis of machine parts or apparatus such as, for example, ball valves. This paper presents the methodology and research results of ball valve in fresh water systems. The opening angle of the valve was changed during the research. The flow of water was measured by a magnetically inductive flowmeter. The research was carried out on a laboratory test stand using an acoustic emission set made by Vallen Inc. This set included: 4 channel signal recorder AMSY 6, two measurement modules ASIP-2/S, preamplifier with a frequency range 20 kHz – 1 MHz and the strengthening of 34 dB and AE signal measurement sensor type VS 150M, with a frequency range 100 – 450kHz. The obtained from the AE-System made by Vallen were compared with the results of the AE-System made by Physical Acoustics (PAC). The PAC system includes preamplifier USB AE Node, type 1283 with bandpass 20 kHz – 1 MHz, AE-Sensor R6D, computer with AE Win for USB Version E5.32 software. During the study, the acoustic emission (AE) generated by flowing water was recorded. The following parameters were determined: amplitude, number of events – hits, the effective value of the signal (RMS). Analysis of the results showed that within a specific range of opening angle of the valve the value of the generated acoustic emission in flowing water increases. This is probably associated with the occurrence of cavitation within the valve. This is an undesirable phenomenon and that these opening angles of ball valve should be avoided in the normal operation.

8

Wykorzystanie emisji akustycznej do diagnozowania wtryskiwacza silnika 3Al25/30

Dudzik K., Charchalis A.

Logistyka

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2015

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nr 3

1077--1083, CD 1

PL

Metoda emisji akustycznej (AE) może być stosowana do diagnostyki części maszyn takich jak np. wtryskiwacze. W artykule przedstawiono metodykę oraz wyniki badań wtryskiwacza silnika 3Al25/30. Badano wtryskiwacz sprawny i z zasymulowaną awarią polegającą na zakoksowaniu 2 z 9 otworków końcówki wtryskiwacza. Badania przeprowadzono na stanowisku laboratoryjnym za pomocą zestawu do rejestracji i analizy emisji akustycznej Vallen System. W skład zestawu wchodzi: 4 kanałowy rejestrator sygnału typu AMSY 6, dwa moduły pomiarowe ASIP-2/S, przedwzmacniacz o zakresie częstotliwości 20kHz - 1MHz i wzmocnieniu 34dB oraz czujnik pomiaru sygnału AE, typu VS 150M, o zakresie częstotliwości 100 -450kHz. W czasie badań emisji akustycznej (AE) generowanej w trakcie wtrysku rejestrowano między innymi parametry: amplituda sygnału, liczba zdarzeń, całkowity czas wtrysku, wartość skuteczna sygnału (RMS). Analiza wyników badań wykazała wyraźnie dłuższy czas całkowity wtrysku w przypadku wtryskiwacza uszkodzonego w porównaniu do wtryskiwacza sprawnego. Amplituda sygnału była większa jednakże RMS sygnału osiągnęła około 3-krotnie mniejszą wartość dla wtryskiwacza z zakoksowaną końcówką. Oznacza to niższą jakość rozpylania paliwa. Przeprowadzone badania mogą być podstawą, do późniejszej identyfikacji ewentualnych uszkodzeń na pracującym silniku, przy wykorzystaniu emisji akustycznej jako skutecznego narzędzia diagnostycznego.

EN

Acoustic emission method (AE) can be used for the diagnosis of machine parts such as, for example: fuel injectors. This paper presents the methodology and research results of 3Al25/30 engine fuel injector. During research was studied one injector in good condition and second with simulated failure involving the closing 2 of 9 holes of the injector tip. Research was carried out on a laboratory test stand using a set of acoustic emission Vallen System. The kit includes: 4 channel signal recorder AMSY 6, two measurement modules ASIP-2/S, preamplifier with a frequency range 20 kHz - 1 MHz and the strengthening of 34dB and AE signal measurement sensor type VS 150M, with a frequency range 100 - 450kHz. During the study, the acoustic emission (AE) generated during the injection was recorded parameters: amplitude, number of events - hits, the total injection time, the effective value of the signal (RMS). Analysis of the results showed significantly longer total time of the injection in the case of damaged injector compared to the injector in good conditions. Signal amplitude was higher, however, the RMS signal reached approximately 3-times lower value for the injector with damaged tip. This means lower quality fuel atomization. The study can be the basis for subsequent identification of possible damages of the engine equipment while the engine is running, using acoustic emission as an effective diagnostic tool.

9

Numerical study on failure behavior of brittle rock specimen containing pre-existing combined flaws under different confining pressure

Yang S. Q., Xu T., He L., Jing H. W., Wen S., Yu Q. L.

Archives of Civil and Mechanical Engineering

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2015

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Vol. 15, no. 4

1085--1097

EN

To understand deeply the fracture mechanism of brittle rock material, the rock specimen containing combined flaws (two square holes and one pre-existing fissure) with seven different fissure angles is carried out the numerical simulation by RFPA2D. Numerically simulated results show a good agreement with the experimental results. The crack coalescence behavior of specimen containing combined flaws under uniaxial compression is summarized, which is closely dependent to fissure angle. The stable propagation of original cracks does not lead to a larger AE event, but the coalescence of new cracks causes a larger AE event. The peak strength of specimen containing combined flaws increases with the confining pressure. According to the linear Mohr–Coulomb criterion, the cohesion and internal friction angle of specimen containing combined flaws are obtained, which is found to take on a distinct nonlinear relation with the fissure angle. The accumulated AE events decreases as the confining pressure increases from 0 to 30 MPa, which results mainly from the restraining of higher confining pressures on the initiation and propagation of tensile cracks at the fissure tips and nearby double squares.

10

Acoustic emission diagnosis for human joint cartilage diseases

Wierzcholski K.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 4

139--148

EN

Purpose: The topic of the presented paper concerns the diagnosis of the wear and diseases of human joint cartilage performed by the acoustic waves emission. The aim of this paper is the determining of the necessary parameters for the diagnosis about the wear and diseases of human joint cartilage. Material And Method: To the research methods used in this paper belong the evaluation of measurement results of the cartilage surface samples obtained by means of laser and mechanical sensor and acoustic emission wave might or voltage gained from the AE apparatus during the treatments performed for normal and pathological used and not used human knee and hip joints. Results: The results concern with the corollaries which are implied from reading values gained by virtue of the acoustic emission Apparatus, and from observations from cartilage surface pictures obtained from laser and mechanical sensors. The diagnose of concrete cartilage illness depends on the proper relative values of obtained strongest of generated AE wave as well as the shapes and amplitudes of acoustic waves and wave frequencies. Conclusions: The main conclusions obtained in this paper are as follows: connections between synovial fluid dynamic viscosity or friction forces and intensity of acoustic emission values, the determination of the type of lesions and deformations of the human joint cartilage surface by means of the shapes architecture of the acoustic emission waves. Moreover are indicated the necessary conditions for the diagnosis of the such dieses as: pathological cartilage with arthritic or osteoporosis or rheumatology changes.

11

Regulacja adaptacyjna procesu szlifowania z wykorzystaniem sygnału emisji akustycznej

Burek J., Babiarz R.

Mechanik

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2012

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R. 85, nr 11

918-925

PL

Przedstawiono cyfrowy układ regulacji adaptacyjnej (AC) procesu szlifowania wgłębnego. Jako wielkość regulowaną wykorzystano sygnał emisji akustycznej (Acoustic Emission - AE). Opisano wyniki badań zastosowania tego układu w szlifierce przemysłowej.

EN

Presented is a digital adaptive system (AC) for control of plunge grinding process. Acoustic emission (AE) signal was used as the controlled variable. Results of the tests on this system performance in application on industrial grinder are discussed.

12

Research on Partial Discharge Localization in XLPE Cable Accessories Using Multi-Sensor Joint Detection Technology

Zheng W., Qian Y., Yang N., Huang Ch., Xiuchen J.

Przegląd Elektrotechniczny

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2011

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R. 87, nr 11

281-284

EN

A multi-sensor joint detection technology was proposed based on the theory of the high frequency current transformer (HFCT) method, Ultra-high frequency (UHF) method and acoustic emission (AE) method. An experimental partial discharge (PD) testing was applied on XLPE cable with artificial defect signals. The experimental results show that the multi-sensor joint detection technology will help to identify the PD signals from the interference noises and improve the localization accuracy.

PL

Zastosowano wielosensorową metodę badania wyładowania niezupełnego: wysokoczęstotliwościowy transformator prądu oraz metodę emisji akustycznej. Badania przeprowadzono na kablu ze sztucznym sygnałem defektu. Umożliwiło to wydzielenie sygnału z szumów i poprawe dokładności pomiaru lokalizacji.

13

Stanowisko do hartowania izotermicznego stali z zastosowaniem emisji akustycznej

Woźniak T. Z., Jeleńkowski J., Rożniatowski K., Ranachowski Z.

Obróbka Metalu

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2010

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nr 1

2-4

PL

Praca zawiera opis stanowiska do badania przemiany austenitu przechłodzonego metodą emisji akustycznej (EA). Wiadomo, że cechy EA są zależne od toru przejścia sygnału i nastaw aparatury pomiarowej, a uzyskiwane wyniki mają charakter jakościowy. Programy do obróbki graficznej umożliwiają rejestrację danych w formie wizualnej i czytelnej. Wykorzystuje się do tego celu szereg specjalistycznych programów komputerowych. Na podstawie uzyskiwanych charakterystyk graficznych EA można wnioskować o kinetyce i mechanizmie przemiany, co zobrazowano na przykładzie hartowania z przemianą izotermiczną stali łożyskowej. W pracy przedstawiono także ogólne podstawy dotyczące metodyki wykonywanych badań oraz rejestracji sygnałów EA.

14

Location Of The Partial Discharges By The Acoustic Emission Method Using The Rogowski Coil

Witkowski P.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

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2009

|

z. 62

73-74

EN

In this paper, results of the research on acoustic emission (AE) signals, which arise during the partial discharges (PDs) generation inside transformer tank filled with synthetic oil, are described. The Rogowski coil is used to determine the propagation time. The signals registered as a function of time are then transformed into the frequency domain using FFT and STFT.

15

Idea Of Time-Frequency Descriptor Dedicated For Analysis Of Signals Originating From Partial Discharges

Kutrasz P.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

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2009

|

z. 62

35-36

EN

In hereof paper architecture of descriptor dedicated for time-frequency analysis of signals originating from partial discharges using method of acoustic emission (AE). The suggested approaches to assume using sigmoidal function as data concentrator.

16

Acoustic Cavitation Intenisty In Insulating Oils

Szmechta M.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

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2009

|

z. 62

65-66

EN

The paper presents some spectral analysis results of acoustic emission observed during ultrasound driven round bottomed flask with fresh insulating oil inside. Collapsing bubbles were responsible for broadband noise included in acoustic emission signal spectra. To represent the cavitation intensity a simple cavitation indicator based on power spectral densities of acoustic emission signal was proposed.

17

A Mobile Measuring System For Analysis Of Partial Discharge Phenomena By The Acoustic Emission Method

Błachowicz A.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

|

2009

|

z. 62

13-14

EN

The paper presents a design project for a mobile system for measuring of parameters of partial discharges (PDs) [1] that occur in insulation of electric power capacitors for compensation of reactive power. Measurements are carried out using acoustic emission (AE) method.

18

Acoustic emission of partial discharges generated in post insulator with a gas void as a defect

Sikorski W., Siodła K.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

|

2004

|

Vol. 40, nr 15

55-61

EN

In the paper, the possibility of utilisation of acoustic emission (AE) for a measurement and analysis of partial discharges generated in a post insulator made of epoxy resin was discussed. The internal defect in the form of a gas void was present inside the insulator. The detailed analyses of registered impulses of AE in frequency domain as well as the use of time-frequency methods were presented.

19

Wykorzystanie czujników z polifluorku winylidenu w diagnostyce urządzeń elektrycznych.

Kisiel A., Woźny L., Mazurek B.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

|

1998

|

Vol. 34, nr 10

161-164

PL

Celem przedstawionej pracy było skonstruowanie czujników piezoelektrycznych z materiałów polimerowych i sprawdzenie możliwości wykorzystania ich do rejestrowania emisji akustycznej (EA) z urządzeń elektrycznych. Badane czujniki wykonano z polifluorku winylidenu (PVDF), formowanego w postaci przewodów. Przetworniki te wykorzystano do pomiarów emisji akustycznej z transformatora wysokiego napięcia i prostownika wysokonapięciowego. Zaobserwowano nietypowe rozkłady przestrzenne i czasowe tempa EA, co może świadczyć o pewnych wadach konstrukcyjnych lub starzeniowych tych urządzeń. W pomiarach EA szczególną uwagę zwrócono na wpływ ekranowania w celu ochrony przed zakłóceniami pochodzącymi od promieniowania elektromagnetycznego, generowanego podczas wyładowań elektrycznych. Stwierdzono, że wpływ ekranowania na mierzoną emisję akustyczną jest bardzo wyraźny, często umożliwiający rejestrację sygnałów EA.

EN

Ultrasonic transducer is one of the most important elements of the acoustic emission (AE) detection system. In this paper the construction of piezoelectric polimere transducers and the possibility of their application to measurement of AE signals from electric devices are presented. Detectors were made from piezoelectric polyfluorine winylidene (PVDF) wire. The were used for measurements of acoustic emission pulses detected from high-voltage transformer and from high-voltage rectifier. The untypical space and time distributions of AE rate were observed. They might be caused by occurrence of constructional faults, some defects or ageing processes of these devices. During measurement it was found that precise cables and detectors shielding against electromagnetic radiation induced after electric breakdown is very important. The significant influence of shielding, especially of detectors AE, on measured acoustic emission signals rate was revealed.

20

Emisja akustyczna z nadprzewodników i rodzaju.

Woźny L., Lubicki P.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

|

1998

|

Vol. 34, nr 10

25-28

PL

Przedstawiono zasady stosowania techniki emisji akustycznej (EA) do badań materiałów nadprzewodzących. Zaprezentowano wyniki rejestracji sygnałów EA z nadprzewodników konwencjonalnych: I rodzaju (ołów) i II rodzaju (niob) i porównano je z odpowiednimi rezultatami, otrzymanymi w przypadku wysokotemperaturowych nadprzewodników ceramicznych.

EN

The principles of acoustic emission (AE) technique use for superconducting materials investigations have been described. Results of AE measurements from conventional superconductors: I kind (lead) and II kind (niobium) have been presented. These results have been compared to the same results for high-temperature ceramic superconductors.