Non-Destructive Evaluation of Coating Thickness Using Water Immersion Ultrasonic Testing

The coating is applied to prevent corrosion on the surface of ships or marine structures, and the thickness of the coating affects its anti-corrosion effect. As a result, non-destructive testing (NDT) is required to measure coating thickness, and ultrasonic NDT is a convenient and quick way to measure the thickness of underwater coatings. However, the offshore coating’s energy attenuation and absorption rates are high, the ultrasonic pulse echo test is difficult, and the testing environment is harsh. Because of the coating’s high attenuation, the distance of the optimal water delay line designed based on the reflection coefficient of the vertically incident wave is used. To accurately measure the thickness of the coating material, TOF of the reflected echo on the time-domain waveform was evaluated. The experimental results show that, when compared to caliper measurements, the coating thickness measured by the proposed method has a lower error and can be used for accurate measurement. The use of ultrasonic water immersion measurement is almost limitless in terms of size, location, and material of the object to be measured, and it is expected to be used to measure the thickness of the surface coating of ships or marine structures in the water.

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Artifact reduction in non-destructive testing by means of complementary data fusion of x-ray computed tomography and ultrasonic pulse-echo testing

Measurement Science and Technology ◽

10.1088/0957-0233/24/12/125403 ◽

2013 ◽

Vol 24 (12) ◽

pp. 125403 ◽

Cited By ~ 9

Author(s):

Michael Schrapp ◽

Thomas Scharrer ◽

Matthias Goldammer ◽

Stefan J Rupitsch ◽

Alexander Sutor ◽

...

Keyword(s):

Computed Tomography ◽

Data Fusion ◽

Ultrasonic Pulse ◽

Artifact Reduction ◽

Non Destructive Testing ◽

Destructive Testing ◽

X Ray ◽

X Ray Computed ◽

Pulse Echo ◽

Non Destructive

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Methods for measuring coating thickness by non-destructive testing

10.3403/00123534u ◽

2015 ◽

Keyword(s):

Coating Thickness ◽

Non Destructive Testing ◽

Destructive Testing ◽

Non Destructive

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Ultrasonic Assessment of Thickness and Bonding Quality of Coating Layer Based on Short-Time Fourier Transform and Convolutional Neural Networks

Coatings ◽

10.3390/coatings11080909 ◽

2021 ◽

Vol 11 (8) ◽

pp. 909

Author(s):

Azamatjon Kakhramon ugli Malikov ◽

Younho Cho ◽

Young H. Kim ◽

Jeongnam Kim ◽

Junpil Park ◽

...

Keyword(s):

Fourier Transform ◽

Coating Layer ◽

Ultrasonic Pulse ◽

Short Time Fourier Transform ◽

Coating Materials ◽

Time Frequency ◽

High Attenuation ◽

Bonding State ◽

The Time Domain ◽

Short Time

Ultrasonic non-destructive analysis is a promising and effective method for the inspection of protective coating materials. Offshore coating exhibits a high attenuation rate of ultrasonic energy due to the absorption and ultrasonic pulse echo testing becomes difficult due to the small amplitude of the second echo from the back wall of the coating layer. In order to address these problems, an advanced ultrasonic signal analysis has been proposed. An ultrasonic delay line was applied due to the high attenuation of the coating layer. A short-time Fourier transform (STFT) of the waveform was implemented to measure the thickness and state of bonding of coating materials. The thickness of the coating material was estimated by the projection of the STFT into the time-domain. The bonding and debonding of the coating layers were distinguished using the ratio of the STFT magnitude peaks of the two subsequent wave echoes. In addition, the advantage of the STFT-based approach is that it can accurately and quickly estimate the time of flight (TOF) of a signal even at low signal-to-noise ratios. Finally, a convolutional neural network (CNN) was applied to automatically determine the bonding state of the coatings. The time–frequency representation of the waveform was used as the input to the CNN. The experimental results demonstrated that the proposed method automatically determines the bonding state of the coatings with high accuracy. The present approach is more efficient compared to the method of estimating bonding state using attenuation.

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Non-Destructive Testing for Concrete: Dynamic Modulus and Ultrasonic Velocity Measurements

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.165 ◽

2011 ◽

Vol 243-249 ◽

pp. 165-169 ◽

Cited By ~ 2

Author(s):

Iqbal Khan Mohammad

Keyword(s):

Compressive Strength ◽

Modulus Of Elasticity ◽

Dynamic Modulus ◽

Ultrasonic Pulse Velocity ◽

Ultrasonic Pulse ◽

Pulse Velocity ◽

Non Destructive Testing ◽

Destructive Testing ◽

Dynamic Modulus Of Elasticity ◽

Non Destructive

Nondestructive testing (NDT) is a technique to determine the integrity of a material, component or structure. The commonly NDT methods used for the concrete are dynamic modulus of elasticity and ultrasonic pulse velocity. The dynamic modulus of elasticity of concrete is related to the structural stiffness and deformation process of concrete structures, and is highly sensitive to the cracking. The velocity of ultrasonic pulses travelling in a solid material depends on the density and elastic properties of that material. Non-destructive testing namely, dynamic modulus of elasticity and ultrasonic pulse velocity was measured for high strength concrete incorporating cementitious composites. Results of dynamic modulus of elasticity and ultrasonic pulse velocity are reported and their relationships with compressive strength are presented. It has been found that NDT is reasonably good and reliable tool to measure the property of concrete which also gives the fair indication of the compressive strength development.

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Classification of Iron Meteorites with High Frequency Ultrasonic Waves

Journal of Environmental and Engineering Geophysics ◽

10.2113/jeeg24.2.277 ◽

2019 ◽

Vol 24 (2) ◽

pp. 277-284

Author(s):

Dris El Abassi ◽

Bouazza Faiz ◽

Abderrahmane Ibhi ◽

Idris Aboudaoud

Keyword(s):

Phase Velocity ◽

Acoustic Impedance ◽

Nickel Content ◽

Normal Incidence ◽

Ultrasonic Pulse ◽

Ultrasonic Waves ◽

Iron Meteorites ◽

Acoustic Transducer ◽

Pulse Echo ◽

Non Destructive

We present the results of an ultrasonic pulse-echo technique and its potential to classify iron meteorites into hexahedrites, octahedrites and ataxites by determining their acoustic impedance and phase velocity. Our technique has been adapted from those used in the field of ultrasonic non-destructive investigation of a variety of materials. The main advantage of our technique is that it does not need any preparation of the meteorites like cutting and etching and therefore is rapid, easy and non-destructive. In essence, a broadband acoustic transducer is used in a monostatic pulse-echo configuration which means that both the transducer and the meteorite sample are located in a water bath and adjusted in the way that the ultrasonic pulse shit the meteorite sample at normal incidence. Then the reflected pulses from the front and rear faces of the meteorite sample are measured with the emitting transducer, digitally recorded and processed to analyze the signal. After Fourier transforming the echoed pulses from the front and the rear face of the meteorite sample, the calculated reflection coefficients yield the phase velocity and the acoustic impedance. Our study investigates a variety of iron meteorites collected in Morocco and other countries and it helps to understand how the nickel content of these meteorites affects the acoustic impedance. It reveals that the acoustic impedance of iron meteorites increases with increasing nickel content, so that a further refinement of our technique might have the potential to classify iron meteorites directly and reliably into hexahedrites, octahedrites and ataxites without destroying them.

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Study on joint detection of fabricated concrete shear wall based on percussion method

MATEC Web of Conferences ◽

10.1051/matecconf/201927703019 ◽

2019 ◽

Vol 277 ◽

pp. 03019

Author(s):

Bo Song ◽

Jian Li ◽

Man sheng Wang

Keyword(s):

Great Influence ◽

Peak Frequency ◽

Joint Detection ◽

Non Destructive Testing ◽

Destructive Testing ◽

Knock Detection ◽

The Time Domain ◽

The Impact ◽

Non Destructive ◽

Peak Value

The knock detection method is one of the non-destructive testing methods for assembly prefabricated components. The knocker is used to knock on the concrete prefabricated components to be tested. The internal conditions of the tested components can be judged by analyzing the time-domain and frequency-domain diagrams of the knocker. In this paper, the impact of the change of the knock point on the detection is studied by using the knock detection experiment. It is found that the location of the knock point has a great influence on the detection. With the change of the position of the knock point, the peak frequency in the spectrum obtained by the detection changes correspondingly. According to the frequency information corresponding to the peak value in the spectrum, the depth of the void to the knock surface can be calculated.

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Quantitative Measurement System of Liquid Products in Sealed Tank

Materials Science Forum ◽

10.4028/www.scientific.net/msf.970.63 ◽

2019 ◽

Vol 970 ◽

pp. 63-74

Author(s):

Yuliya Shulgina ◽

Maria A. Kostina ◽

P.V. Sorokin ◽

Marina Polonskaya ◽

O.A. Kozhemyak ◽

...

Keyword(s):

Quantitative Measurement ◽

Optimal Solution ◽

Storage Conditions ◽

Ultrasonic Pulse ◽

Non Destructive Testing ◽

Destructive Testing ◽

Wide Range ◽

Liquid Products ◽

Manometric Method ◽

Non Destructive

Many industries apply pressure tanks for the storage of various types of liquids [1]. It can be toxic, chemically active liquids or food products. Storage conditions of these liquids can have a wide range of pressures and temperatures; therefore it is preferable to control the liquids levels from the outside of the tank. The most optimal solution in this case is the ultrasonic pulse time method [2-6], which is also widely used in robotics [7], fishing, shipping [8-9], archeology [10-11], non-destructive testing [12-17] and manometric method [18].

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Using Support Vector Machine to Improve Ultrasonic Pulse Velocity Test for Concrete

MATEC Web of Conferences ◽

10.1051/matecconf/201820701001 ◽

2018 ◽

Vol 207 ◽

pp. 01001

Author(s):

Tu Quynh Loan Ngo ◽

Yu-Ren Wang

Keyword(s):

Compressive Strength ◽

Ultrasonic Pulse Velocity ◽

Ultrasonic Pulse ◽

Pulse Velocity ◽

Support Vector ◽

Non Destructive Testing ◽

Testing Methods ◽

Destructive Testing ◽

Compressive Strength Of Concrete ◽

Non Destructive

In the construction industry, to evaluate the compressive strength of concrete, destructive and non-destructive testing methods are used. Non-destructive testing methods are preferable due to the fact that those methods do not destroy concrete samples. However, they usually give larger percentage of error than using destructive tests. Among the non-destructive testing methods, the ultrasonic pulse velocity test is the popular one because it is economic and very simple in operation. Using the ultrasonic pulse velocity test gives 20% MAPE more than using destructive tests. This paper aims to improve the ultrasonic pulse velocity test results in estimating the compressive strength of concrete using the help of artificial intelligent. To establish a better prediction model for the ultrasonic pulse velocity test, data collected from 312 cylinder of concrete samples are used to develop and validate the model. The research results provide valuable information when using the ultrasonic pulse velocity tests to the inputs data in addition with support vector machine by learning algorithms, and the actual compressive strengths are set as the target output data to train the model. The results show that both MAPEs for the linear and nonlinear regression models are 11.17% and 17.66% respectively. The MAPE for the support vector machine models is 11.02%. These research results can provide valuable information when using the ultrasonic pulse velocity test to estimate the compressive strength of concrete.

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