Nondestructive Detection Technique Research Articles

Advanced Characterization Techniques for Turbine Blade Wear and Damage

This paper presents four complementary non-destructive measurement techniques for material characterization and damage detection of turbine blades. The techniques are macroscopic fringe projection with inverse fringe projection algorithms, robot guided microscale fringe projection, high frequency eddy current and pulsed high frequency induction thermography, both in the megahertz range. The specimen on which the measurements were carried out is a blade of the 1st stage high pressure turbine of a modern airplane jet engine. The turbine blade was characterized with regard to the macroscopic and microscopic geometry, cracks in the base material as well as the condition of the protective layer system.

Development of magnetic flux leakage measuring system for detection of defect in small diameter steam generator tube

Abstract Magnetic flux leakage based non destructive technique for detection of defect in small diameter steam generator tube is evaluated. The detect-ability of a flaw depends on the magnetic flux density passing through a specimen to be inspected. The process of magnetizing local region of the small diameter tube is complex, when the magnetizer arrangement is placed inside the tube. Bobbin coil is considered to magnetize the local region of small diameter ferromagnetic tube and a hall sensor is placed at the center of the magnetizer to sense the leakage field. ANSYS Maxwell EM V16 based Finite Element Method (FEM) and Analytical model is used to validate the proposed magnetizer arrangement. Experimental results were found to be in good agreement with both numerical and analytical results. The obtained results suggest that the performance of the proposed bobbin coil is good to inspect the small diameter tube.

Experimental research on detection for interface debond of CFRP T-joints under tensile load

The interface debond initiation and evolution of Carbon Fiber Reinforced Polymer (CFRP) T-joints (T700/QY8911) under static load are studied in this paper. The experiment test is conducted by using the active Lamb-wave-based damage non-destructive detection technique associated with piezoelectric sensors to pitch and catch the wave signals as well as a high-speed camera to record the failure behaviors of the specimen. The PZT sensors is arranged sequentially along the predicted path in which the debond damage propagates. Furthermore, the real-time monitoring method is also applied to extract the wave characteristic parameters, including Vpp of direct wave, Amplitude Damage Index (ADI) and total wave energy, for efficiently describing the damage status of the T-joint during the tensile process. Of which the Amplitude Damage Index (ADI) is considered to indicate initial damage warning and the damage propagation is qualitatively analyzed by observing the consolidated trends of the wave characteristics. The debond behavior of the T-joint obtained by the high-speed camera is also analyzed accompanied with the Lamb-wave characteristic curves. The Lamb-wave-based detection results could be found in a good coincidence with the load-displacement response as well as the measurement strain-time curve obtained by the Fiber Bragg Grating (FBG).

Evaluation of Near-Infrared and Mid-Infrared Spectroscopy for the Determination of Routine Parameters in Chinese Rice Wine

The goals of this study were to apply near-infrared (NIR) and mid-infrared (MIR) spectroscopy for the determination of routine quality parameters in Chinese rice wine, and compare the performance of the two spectroscopic methods. A total of 80 rice wine samples were measured by NIR and MIR spectroscopy. Calibration modes were established by three chemometric methods with full cross-validation. The result indicated that the performance of partial least squares regression models was the best. MIR method was found to be better than NIR for alcohol degree ( =0.942, RPD=4.3), total sugar ( =0.974, RPD=6.0), nonsugar solid ( =0.910, RPD=3.2) and total acid ( =0.854, RPD=2.6) content determination. On the other hand, NIR was a little superior for pH value ( =0.797, RPD=2.3) determination. The results provided useful information to understand the difference between the two spectroscopic methods and to determine the most suitable method for Chinese rice wine quality supervision. Practical Applications Both near-infrared (NIR) and mid-infrared (MIR) spectroscopy are very attractive techniques for nondestructive detection of quality of food products. The present study was to carry out a comparative study to evaluate NIR and MIR spectroscopy combined with chemometrics for the determination of routine parameters in rice wine, namely alcohol degree, total sugar, total acid, nonsugar solid and pH value, and to evaluate their efficiency and predictive power for unknown samples. This study could provide useful information to understand the difference between the two methods and to determine the most suitable method for the brewery industry.

Review of Electromagnetic-Based Crack Sensors for Metallic Materials (Recent Research and Future Perspectives)

Evaluation and non-destructive identification of stress-induced cracks or failures in metals is a vital problem in many sensitive environments, including transportation (steel railway tracks, bridges, car wheels, etc.), power plants (steam generator tubing, etc.) and aerospace transportation (landing gear, aircraft fuselages, etc.). There are many traditional non-destructive detection and evaluation techniques; recently, near-field millimeter waves and microwave methods have shown incredible promise for augmenting currently available non-destructive techniques. This article serves as a review of developments made until now on this topic; it provides an overview of microwave scanning techniques for crack detection. This article summarizes the abilities of these methods to identify and evaluate cracks (including describing their different physical properties). These methods include applying filters based on dual-behavior resonators (DBRs), using complementary split-ring resonators (CSRRs) for the perturbation of electric fields, using waveguide probe-loaded CSRRs and using a substrate-integrated-waveguide (SIW) cavity for the detection of sub-millimeter surface and subsurface cracks.

3D characterization of rolling contact fatigue crack networks

Rolling contact fatigue (RCF) damage is becoming more frequent with increased traffic, accelerations, and loading conditions in the railway industry. Defects which are characterized by a two-lobe darkened surface and a V-shaped surface-breaking crack are defined as squats. The origination and propagation of squats in railway rails is the topic of many recent studies; the associated crack networks develop with complicated geometry near the surface of rails, but can be difficult to detect and distinguish from normally existing head checks in their early stages, using in-field non-destructive detection techniques. After cutting out damaged sections of rail, there are a number of options to characterize the damage. The aim of this study was to evaluate different methods to geometrically describe squat crack networks; through X-ray radiography complemented with geometrical reconstruction, metallography, X-ray tomography, and topography measurements. The experiments were performed on squats from rail sections taken from the field. In the first method, high-resolution and high-energy X-ray images exposed through the entire rail head from a range of angles were combined using a semi-automated image analysis method for geometrical reconstruction, and a 3D representation of the complex crack network was achieved. This was compared with measurements on cross-sections after repeated metallographic sectioning to determine the accuracy of prediction of the geometrical reconstruction. A second squat was investigated by X-ray tomography after extraction of a section of the rail head. A third squat was opened by careful cutting, which gave full access to the crack faces, and the topography was measured by stylus profilometry. The high-energy X-ray, 3D reconstruction method showed accurate main crack geometry at medium depths; the advantage of the method being that it potentially could be developed for non-destructive testing in field. However significant drawbacks exist due to limitations in radiography in terms of detecting tightly closed cracks in very thick components. This includes the inability to detect the crack tips which is an important factor in determining the risks associated to a specific crack. Metallographic investigation of the cracks gave good interpretation of crack geometry along the sections examined, and gave the possibility to study microstructure and plastic deformation adjacent to the crack face. However this time-consuming method requires destruction of the specimen investigated. The X-ray tomography revealed the 3D crack network including side branches in a 10×10×30mm3 sample, and provided topographic information without completely opening the squat. Topography measurements acquired by stylus profilometry provided an accurate description of the entire main crack surface texture, including features such as surface ridges and beach marks.

Interface and permittivity simultaneous reconstruction in electrical capacitance tomography based on boundary and finite-elements coupling method.

Electrical capacitance tomography (ECT) is a non-destructive detection technique for imaging the permittivity distributions inside an observed domain from the capacitances measurements on its boundary. Owing to its advantages of non-contact, non-radiation, high speed and low cost, ECT is promising in the measurements of many industrial or biological processes. However, in the practical industrial or biological systems, a deposit is normally seen in the inner wall of its pipe or vessel. As the actual region of interest (ROI) of ECT is surrounded by the deposit layer, the capacitance measurements become weakly sensitive to the permittivity perturbation occurring at the ROI. When there is a major permittivity difference between the deposit and the ROI, this kind of shielding effect is significant, and the permittivity reconstruction becomes challenging. To deal with the issue, an interface and permittivity simultaneous reconstruction approach is proposed. Both the permittivity at the ROI and the geometry of the deposit layer are recovered using the block coordinate descent method. The boundary and finite-elements coupling method is employed to improve the computational efficiency. The performance of the proposed method is evaluated with the simulation tests. This article is part of the themed issue 'Supersensing through industrial process tomography'.

Near-field microwave identification and quantitative evaluation of liquid ingress in honeycomb sandwich structures

Honeycomb sandwich structures are susceptible to liquid ingress, which causes a serious degradation of performance. Herein, a near-field microwave nondestructive detection technique was proposed to detect, identify, and quantitatively evaluate liquid ingress in honeycomb sandwich structures. Based on the microwave reflection spectrums, liquids of different polarity properties were identified. The amplitude of reflection microwaves was found nearly linear with respect to the height of the intruding liquids in the near field of the coaxial adapter probe. A simple characteristic peak method (CPM) based on line scans was presented and applied to quantify the size of liquid ingress region, and it turned out to be quite accurate with relative errors less than 0.5%. In summary, the near-field microwave testing technique proposed in this study is effective to detect, identify, and quantify liquid ingress in honeycomb sandwich structures.

Regression Algorithms in Hyperspectral Data Analysis for Meat Quality Detection and Evaluation.

Hyperspectral imaging (HSI) system in tandem with chemometric methods is proposed as a rapid, efficient, cost-saving, and nondestructive detection technique, and multivariate data analysis is an indispensable part of this novel detection technique. In recent years, the rapid progress that we have made in using all kinds of chemometric methods to deal with hyperspectral data of meat products, however, cannot meet the practical needs very well. Thus, in order to give some suggestions on how to select an appropriate algorithm for hyperspectral data analysis, this review, first, briefly introduces the principle of the most widely used regression algorithms, and, more importantly, then focuses on the application of different algorithms in modeling the correlation between the quality attributes of the tested sample and their hyperspectral data. The advantages and limitations of these algorithms are compared and discussed. This review article will provide valuable guidelines for data analysis in the future progress of HSI detection technique.

Nondestructive diagnostics of charged particle beams in accelerators

The basic techniques for nondestructive diagnostics and detection of losses of charged particle beams used in accelerator engineering are reviewed. The data provided may help choose the systems for diagnostics and detection of losses of beams and give a qualitative picture of the operation principles of such devices. Quantitative characteristics that define the limits of applicability of each diagnostic technique are outlined.

Use of the random decrement technique for nondestructive detection of damage to beams

The random decrement (RD) technique is a time-domain procedure in which the random structural response under service loads is transformed into the free decay response. The RD technique is used for monitoring and determining structural performance, being able to predict damage and handle the occurrence of sudden failures during operation of the structure. The technique is considered a unique method for nondestructive testing. The RD signature can be utilized as a damage indicator. The technique is based on output measurements, whereas both input and output measurements are required for other, traditional methods commonly used in aerospace and mechanical engineering, including frequency- and time-domain methods such as the frequency response function and state equation. In civil engineering, input excitation forces such as wind, earthquake, and traffic loads are often hard to determine. The RD technique determines the changes of the structure’s dynamic parameters according to external forces without knowledge of the magnitude of the excitation forces. The method is already considered efficient for detecting damage to steel structural members, so the current study focuses on use of the RD technique to determine dynamic parameters for reinforced-concrete (RC) members and explores the possibility of determining the presence of damage and its location. The main focus of this research work is assessment of the suitability of RD for monitoring RC beams. Two laboratory investigations were performed to determine the applicability of the RD technique for RC members and compare the indication of damage using a random signature for RC and steel beams. The beams were excited randomly, then the response signals were detected and the dynamic response signature was calculated at each stage. The RC beam was subjected to damage by applying a concentrated load at its midpoint, while the steel beam was subjected to different structural damage ratios by cutting the cross section to 25, 50, and 75 % damage ratio using a mechanical saw. The natural frequencies and damping ratios were calculated for different applied loads on the RC beam and the steel beam for different damage ratios. The changes in the dynamic parameters of the structure were determined for both undamaged and damaged beams. The investigation indicates the role of the change in the random signature due to damage, which was detected for different damage ratios for steel and RC beams, also revealing the particular significance of this technique for small damage and cracks. The results indicate meaningful changes in damping values that enable detection of the level of damage for the RC beam. The RD technique provides a promising, efficient approach for determination of dynamic parameters for important structures.

Estimation of Depth and Length of Defects from Magnetic Flux Leakage Measurements: Verification with Simulations, Experiments, and Pigging data

Magnetic flux leakage (MFL) method is the most widely used non-destructive testing techniques for detection and characterization of defects in product transmission pipelines. The maximum safe operating pressure is a crucial parameter in practice, which is predicted with respect to the length, width, and depth of defects. In a previous work, an algorithm is devised to detect and estimate the width of the defect based on MFL signals. In this paper, an efficient method based on axial MFL level contours is devised to estimate the length of the defect. This method uses the patterns of signal level contours in the region corresponding to the defect's area. In addition, a Gaussian radial basis function neural network (NN) is trained to approximate the depth of the defect. The NN is fed with the estimated length, width, and signal peak-to-peak values, and the output of the network is the estimated depth. The proposed detection and estimation method is applied to MFL measurements to detect and determine the sizing of metal loss defects. The efficacy and accuracy of the proposed methods are examined through a rich set of sample defects that contains simulated defects, designed defects that are carved on a real pipe by milling, and actual pigging data validated by several dig up verifications. Obtained results confirm the effectiveness and accuracy of the proposed depth and length estimation method along with the previously devised detection and width estimation methods, in characterization of metal loss defects.

Development of the antipodal Vivaldi antenna for detection of cracks inside concrete members

ABSTRACTUltrawide band (UWB) nondestructive testing and evaluation techniques can provide the detection of defects and damages in construction materials and members. The development of UWB antennas with proper dimensions and high performance for these systems is one of the major challenges. In this letter, an antipodal Vivaldi antenna (AVA) has been developed to be used in UWB techniques for nondestructive detection of cracks in concrete members. To obtain a desirable antenna performance including the wider impedance bandwidth, the higher directivity, and higher front‐to‐back ratio rectangular‐shaped slits (RSS) and a half‐circular‐shaped lens (HCSL) have been added in the design of a conventional tapered slot AVA. A parametric study on the dimensions of the slits is provided to optimize performance and size of the proposed antenna. The optimum size of the proposed antenna is 40 × 80 × 0.508 mm3, and it operates over the frequency range from 3.4–40 GHz. It is shown that the RSS increase impedance bandwidth especially at the lower frequencies. Directivity of the proposed antenna at higher frequencies has been increased by the HCSL. The feasibility of the proposed antenna for nondestructive evaluation of concrete members is demonstrated by investigation into its performance with concrete specimens possessing an air‐gap inside a concrete specimen. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1573–1578, 2015

A Hyphenated Technique based on High-Performance Thin Layer Chromatography for Determining Neutral Sphingolipids: A Proof of Concept

Hyphenated HPTLC has been used to analyze several neutral sphingolipids acting as lysosomal storage disease (LSD) biomarkers. Automated multiple development (AMD) provides separation of lipid peaks, which are detected and quantified using fluorescence detection by intensity changes (FDIC) after primuline post-impregnation. A final online transfer to a mass spectrometer by means of an elution-based interface allows their identification using electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI).Given that the increases in fluorescent emission detected by FDIC are produced by non-specific, electrostatic interactions between the primuline and hydrocarbon chains in the ceramide backbones of sphingolipids, it is a non-destructive detection technique, allowing the precise location and transfer of biomarker peaks to a mass spectrometer using an elution interface. By using primuline as a fluorophore, the technique is also compatible with ESI-APCI and does not interfere with the MS of sphingolipids. APCI provides useful and complementary structural information to the ESI for sphingolipid identification. Moreover, FDIC emission can be used for quantitative purposes. Results include the determination of sphingomyelin (SM) in human-plasma samples (RSD < 6%) by means of a standard addition method with non-linear calibration, and the identification of globotriaosylceramide (Gb3) in the plasma of a Fabry patient. Only one HPTLC plate is needed to perform the analysis.

Spectroscopic Techniques for Nondestructive Detection of Fungi and Mycotoxins in Agricultural Materials: A Review

Purpose: Fungal secondary metabolite (mycotoxin) contamination in foods can pose a serious threat to humans and animals. Spectroscopic techniques have proven to be potential alternative tools for early detection of mycotoxins. Thus, the aim of this review is to provide an overview of the current developments in nondestructive food safety testing techniques, particularly regarding fungal contamination testing in grains, focusing on the application of spectroscopic techniques to this problem. Methods: This review focuses on the use of spectroscopic techniques for the detection of fungi and mycotoxins in agricultural products as reported in the literature. It provides an overview of the characteristics of the main spectroscopic methods and reviews their applications in grain analysis. Results: It was found that spectroscopy has advantages over conventional methods used for fungal contamination detection, particularly when combined with chemometrics. These advantages include the rapidness and nondestructive nature of this approach. Conclusions: While spectroscopy offers many benefits for the detection of mycotoxins in agricultural products, a number of limitations exist, which must be overcome prior to widespread adoption of these techniques.

Flat nose low velocity drop-weight impact response of carbon fibre composites using non-destructive damage detection techniques

AbstractThis work is mainly concerned with the nondestructive post-impact damage evaluation of carbon fibre reinforced laminated composite panels subject to low velocity drop-weight impact by flat and round nose impactors. Quasi-isotropic laminates consisting of eight-, sixteen-, and twenty-four plies were impacted by flat and round nose impactors at different velocity levels. Load-time history data were recorded and plotted to correlate loaddrop as damage level to the impactor nose profiles. Test produced data, non-destructive damage detection techniques: visual, ultrasonic, and eddy- current, and computer simulations were utilised to identify and quantify status of the impact induced damage. To evaluate damage in relatively thick laminates (consisting of 24-Ply), the damage ratios and deflection quantities were correlated to the corresponding impactor nose profiles. Damage induced by the flat nose impactor to thick laminates was compared against the data produced by the round nose impactor. Results show that relatively thin laminates were largely affected by the impactor nose. Reasonable difference was observed in damage caused by flat and round impactor nose profiles to thick laminates impacted at relatively higher velocity impacts. Resultswere compared and validated against simulation produced data.

A Novel Texture Extraction Method for Digital Radiography

As known, there always exist severely degradation problems in digital radiography. How we can extract necessary textures from degraded radiographic images is the post-processing key. Local binary pattern (LBP) is a well-known method, which is widely used in fast image texture extraction. However, for noisy images, LBP can’t work well due to its sensitivity to details. On the other hand, as one of the important shock filters developed in recent years, complex shock filter possesses excellent capabilities in textural image processing. Here, by combining complex shock filter with LBP, a novel fast and efficient method, C-LBP is presented for texture extraction of degraded radiographic images. Experimental results show that comparing with traditional LBP, C-LBP not only distinguishes between noise and details in radiographic images, but also extracts image textures efficiently and rapidly, which plays an important role in developing nondestructive detection technique by low-dose ray radiography.

Open crack depth sizing by laser stimulated infrared lock-in thermography

Recent advances in infrared imaging have made active thermography an interesting non destructive technique for sub-surface defect detection. Here, we present a method for the estimation of the depth of open surface defects by infrared lock-in thermography, based on the relation between the crack depth and the Laplacian of the surface temperature distribution induced by a local heating using a laser. A comparison to numerical finite element modelling for different depths allows an accurate determination of fatigue crack depth in Inconel alloy test blocks.

English

 Abstract—Some of the aspects of maintenance of mango fruit quality during the supply chain are harvesting practices, adequate orchard management practices, postharvest treatments, transportation and storage conditions, packing operation, temperature management and ripening at destination. Since the said area is a newly growing field, very little literature is available on the defect detection of alphonso mango. The quality attributes of alphonso include freedom from external damages such as latex or sap injury and decay, bruises, uniform weight, color, aroma, firmness, shape and size. Postharvest losses are high during the supply chain due to harvesting fruit at improper maturity, sap burn, mechanical damage during the whole chain, spongy tissue, lenticels discoloration, decay, chilling injury, fruit softening and disease and pest damage. The main aim of postharvest treatments and management practices in the supply chain is to create suitable conditions or environments to extend the storage life and retain the quality attributes, nutrition and functional compositions. To retain the overall mango fruit quality and to reduce postharvest losses during supply chain can be achieved by adopting suitable postharvest novel technologies involving image processing and pattern recognition techniques. To achieve this task the researchers in this area needs the database that contains healthy as well as Spongy Tissue affected alphonso mangoes. This paper is an attempt towards the direction to develop such database for the researchers working on the non-destructive techniques for defect detection in mangoes. Keywords—Alphonso Mangoes, Spongy Tissue, digital X-Ray imaging, database of alphonso, Non-Destructive Testing.

Detection and Monitoring Technologies of Bridge Cable Force and Disease

Investigation is carried out aiming at analysis of bridge cable detection and monitoring. Detection and monitoring technology characteristics are summarized, while technology advantages and disadvantages analyzed. Dynamic detection technology of cable force is used most often. Effects of various factors of this technology are analyzed. Cable structure internal and external injury detection technologies are analyzed. Nondestructive testing technology specific comparison is carried out, the advantages and disadvantages of each technology and application. Nondestructive damage detection technique prospect is presented.