TY - CONF A1 - Küttenbaum, S. A1 - Braml, T. A1 - Kainz, C. A1 - Maack, Stefan A1 - Taffe, A. T1 - Guidance on inspection-supported reliability assessment of existing bridges in Germany N2 - This contribution is intended to disseminate the contents of a national recommendation for Action draft for the inspection-based reliability analysis of existing bridges. The focus is on the utilization of non-destructive testing methods for verifications in both the ultimate and the serviceability Limit states. First, the contents of the developed recommendation for action are outlined. The Guideline covers the process from the purposeful definition of inspection strategies via the quality assessment of measured information to the partial factor-based assessment under consideration of qualityevaluated on-site inspection results. Secondly, the concept of the drafted recommendation for action is demonstrated using a prestressed concrete bridge as a case study. T2 - IABSE Symposium Tokyo 2025 CY - Tokyo, Nippon DA - 18.05.2025 KW - Life management KW - Brücken KW - Non-destructive testing KW - Civil engineering KW - State-of-the-art PY - 2025 DO - https://doi.org/10.1080/10168664.2024.2363597 VL - 34 IS - 3 SP - 1 EP - 8 AN - OPUS4-65630 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gaal, Mate A1 - Álvarez-Arenas, Tomás Gómez T1 - Guest Editorial: Special Section on Air-Coupled Ultrasound N2 - Air-coupled ultrasound is a challenging field dominated by the drastic impedance mismatch between air and all condensed matter, the low ultrasound velocity in the air, and the rapidly increasing attenuation with frequency. The seven articles included in this special section showcase the diversity of current research on air-coupled ultrasound. All contributions in this special section are application-oriented, demonstrating the readiness of air-coupled ultrasound technologies to address real-world challenges. Whether it’s ensuring food safety, supporting heritage conservation, optimizing industrial inspection, or enabling in-field biological measurements, the practical relevance of these studies makes this section particularly valuable for both researchers and industry professionals. KW - Air-coupled ultrasound KW - Transducers KW - Non-destructive testing PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655041 DO - https://doi.org/10.1109/OJUFFC.2026.3656857 SN - 2694-0884 VL - 6 SP - 1 EP - 2 PB - Institute of Electrical and Electronics Engineers (IEEE) AN - OPUS4-65504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hirsch, Philipp Daniel A1 - Kunji Purayil, Sruthi Krishna A1 - Lecompagnon, Julien A1 - Pech May, Nelson Wilbur A1 - Ziegler, Mathias ED - Maldague, X. T1 - Robotic-Assisted 3D Scanning and Laser Thermography for Crack Inspection on Complex Components N2 - The integration of automation and robotics into non-destructive testing (NDT) marks a significant advancement in evaluating complex components. This paper introduces a novel approach using robotic-assisted laser thermography combined with automated 3D scanning to detect and analyze cracks in complex structures. The system uses an integrated line scanner with a robotic arm to capture high-resolution data, creating detailed 3D models for adaptive path planning and precise alignment correction. Laser thermography, based on localized heating and the "flying spot" approach, detects surfacenear cracks with high precision. Crack detection is achieved using the Canny algorithm optional on Fourier-transformed thermograms, offering robust results with minimal computation. This study highlights the potential of robotic-assisted 3D scanning and laser thermography as efficient and precise methods for crack inspection, advancing NDT technologies and ensuring the structural integrity of modern components. T2 - 17th International Conference on Quantitative InfraRed Thermography 2024 CY - Zagreb, Croatia DA - 01.07.2024 KW - Thermography KW - Non-destructive testing KW - Laser line KW - Robotic arm KW - Defect identification KW - Crack detection PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653809 DO - https://doi.org/10.21611/qirt-2024-078 SP - 1 EP - 8 PB - QIRT Council AN - OPUS4-65380 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zeipert, H. A1 - Nellius, T. A1 - Schönlau, N. A1 - Wippermann, M. A1 - Claes, L. A1 - Henning, B. A1 - Nicolai, Marcel A1 - Prager, J. T1 - C6-a3 - Monitoring the curing process of adhesive bonds using selective excitation of guided ultrasonic waves N2 - A measurement setup for the selective excitation of guided ultrasonic waves in adhesively bonded plates is introduced. Changes of the dispersive behaviour of the guided waves during the curing process is known to be accompanied by a change in the propagating waves group velocities. The proposed measurement setup is used to monitor that change during the curing process of an aluminium-epoxy-polycarbonate bond. T2 - 2025 ICU PADERBORN - 9th International Congress on Ultrasonics CY - Paderborn, Germany DA - 21.09.2025 KW - Ultrasonic guided waves KW - Selective excitation KW - Non-destructive testing KW - Adhesive bonding KW - Condition monitoring PY - 2025 DO - https://doi.org/10.5162/Ultrasonic2025/C6-a3 SP - 207 EP - 210 PB - AMA Service GmbH AN - OPUS4-65357 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Quosdorf, Heike T1 - Digital object identifier for additively manufactured parts as software package N2 - A method to uniquely identify samples without printed or handwritten labels is an advantage not just for additively manufactured parts. To kickstart industry use cases, it is also important to provide a ready-made implementation kit. Following an open-science and open-source software approach Germanys Federal Institute for Materials Research and Testing (BAM) seeks to promote digital solutions of ongoing research projects. With this software package a novel method based on microstructural features as identifiers – DOI4AM (digital object identifier for additively manufactured parts) – will be explained alongside its implementation as open-source Python software package. The digital object identifier (DOI) links product data clearly and forgery-proof with real components. Its implementation helps to identify and securely authenticate additively manufactured components during its product life cycle by using characteristic microstructure features - just like a fingerprint. To calculate the DOI fingerprint, a few preprocessing steps need to be performed to detect the uniquely distributed microstructure features that occur during the 3D printing process. A go-through guide shows the preprocessing steps that include CT image capturing, feature segmentation, and data distribution with CSV files. While all steps can be followed along in a Jupyter notebook, the software package includes an application for creating and checking of previously created fingerprints, as well, as a containerized API (application programming interface) service for implementation in existing software platforms or workflows. While data visualization is crucial to understanding the methodology and an essential tool to check for data correctness, an implementation in an industry use case needs to be slim and resource efficient. Therefor the software’s API can be used as an independent service. The project's industry partner proofs its first successful implementation in their digital product passport web solution PASS-X. T2 - AI MSE 2025 CY - Bochum, Germany DA - 18.11.2025 KW - Authentication KW - Unique identification KW - Digital object identifier KW - Additive Manufacturing KW - Non-destructive testing KW - Open Source Software KW - Digital fingerprint KW - X-ray Computed Tomography KW - Open Science PY - 2025 AN - OPUS4-65293 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waske, Anja T1 - A unique authenticator for additively manufactured parts derived from their microstructure N2 - In the field of additive manufacturing, the ability to uniquely identify and authenticate parts is crucial for certification, logistics, and anti-counterfeiting efforts. This study introduces a novel methodology that leverages the intrinsic microstructural features of additively manufactured components for their identification, authentication, and traceability. Unlike traditional tagging methods, such as embedding QR codes on the surface [1] or within the volume of parts, this approach requires no alteration to the printing process, as it utilizes naturally occurring microstructural characteristics. The proposed workflow [2] involves the analysis of 3D micro-computed tomography data to identify specific voids that meet predefined identification criteria. This method is demonstrated on a batch of 20 parts manufactured with identical process parameters, proving capable of achieving unambiguous identification and authentication. By establishing a tamper-proof link between the physical part and its digital counterpart, this methodology effectively bridges the physical and digital realms. This not only enhances the traceability of additively manufactured parts but also provides a robust tool for integrating digital materials, parts databases, and product passports with their physical counterparts. T2 - Artificial Intelligence in MSE CY - Bochum, Germany DA - 18.11.2025 KW - Authentication KW - Additive Manufacturing KW - Non-destructive testing PY - 2025 AN - OPUS4-65204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waske, Anja T1 - A unique authenticator for additively manufactured parts derived from their microstructure N2 - The international research community is currently devoting extensive resources to the development of digital material data spaces and the associated digital twins and product passports of materials and components. A common weak link in these projects to date has been the connection between physical components / samples and their digital data and documents. This is where the concept of the unique identification comes in. Components produced using additive manufacturing can be marked for unique identification and secure authentication [1,2]. Serial numbers and machine-readable codes can be used to identify the component, and link digital product-related data (i.e., a digital product passport) to the actual components. The most prevailing solution consists of local process manipulation, such as printing a quick response (QR) code [3] or a set of blind holes on the surface or the internal cavity of hollow components. However, local manipulation of components may alter the properties, and external tagging features can be altered or even removed by post-processing treatments. This work provides a new methodology for identification, authentication, and traceability of additively manufactured (AM) components using microstructural features that are unique to each part. X-ray computed tomography (XCT) was employed to image the microstructural features of a batch of AlSi10Mg parts. Based on size and geometry, the most prominent features were selected to create a unique digital authenticator. We implemented a framework in Python using open-access modules that can successfully create a digital object authenticator using the segmented microstructure information from XCT. We show that this method allows to authenticate individual parts from the build job based on its microstructural fingerprint. This is our contribution to enhancing the security and product protection of additively manufactured components. T2 - FEMS EUROMAT CY - Granada, Spain DA - 15.09.2025 KW - Authentication KW - Fingerprint KW - Non-destructive testing PY - 2025 AN - OPUS4-65202 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waske, Anja T1 - A unique authenticator for additively manufactured parts derived from their microstructure N2 - Components produced using additive manufacturing can be marked for unique identification and secure authentication [1,2]. Serial numbers and machine-readable codes can be used to identify the component, and link digital product-related data (i.e., a digital product passport) to the actual components. The most prevailing solution consists of local process manipulation, such as printing a quick response (QR) code [3] or a set of blind holes on the surface of the internal cavity of hollow components. However, local manipulation of components may alter the properties, and external tagging features can be altered or even removed by post-processing treatments. This work therefore aims to provide a new methodology for identification, authentication, and traceability of additively manufactured (AM) components using microstructural features that are unique to each part. X-ray computed tomography (XCT) was employed to image the microstructural features of AlSi10Mg parts. Based on size and geometry, the most prominent features were selected to create a unique digital authenticator. We implemented a framework in Python using open-access modules that can successfully create a digital object authenticator using the segmented microstructure information from XCT. The authenticator is stored as a QR code, along with the 3D information of the selected features. T2 - MRS Spring Meeting Seattle CY - Seattle, WA, USA DA - 07.04.2025 KW - Additive Manufacturing KW - Fingerprint KW - Non-destructive testing PY - 2025 AN - OPUS4-65199 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nicolicea, Alberto T1 - Flexible AMR sensors for novel non destructive testing capabilities N2 - Reshapeable magnetic field sensors fabricated on flexible substrates by thin-film deposition or printing have recently emerged with promising applications in different field. In this study, flexible anisotropic magneto-resistive (AMR) sensors were used for the scanning of a curved and flat sample with reference defects, to prove the capability of this method for curved surface scanning, and to benchmark the performance when compared to a more stand-ard method using rigid giant magneto-resistive (GMR) sensors. Defects with depths ranging from 110 μm up to 2240 μm were detected with a signal-to-noise ratio (SNR) of 2.7 up to 27.9 employing flexible AMR sensors. T2 - XMR-Symposium CY - Wetzlar, Germany DA - 12.03.2025 KW - Non-destructive testing KW - Flexible sensor KW - Magnetoresistance PY - 2025 AN - OPUS4-65033 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nicolicea, Alberto T1 - Flexible magnetoresistive sensors for novel applications N2 - Flexible electronics is an emerging field that has been gaining a lot of attention in recent years, with the appearance of flexible solar panels, screens and other such novel devices. Recent developments in this area have lead to the appearance of flexible magnetic field sensors which are produced by thin-film deposition on flexible substrates. These devices show promising capabilities for several applications such spatial navigation, micro-fluidic particle detection, biomedical applications and intelligent textiles [1]. One possible field of interest is the application of these devices for electromagnetic (EM) non-destructive testing (NDT), since it would enable in-contact scanning of surfaces with arbitrary shapes. Flexible anisotropic magnetoresistive (AMR) sensors mounted on a rotative mechanical holder were used to scan a semi-circular ferromagnetic sample with 3 reference defects via magnetic ux leakage (MFL) testing, thus demonstrating the applicability of this method for the scanning of curved surfaces. T2 - SMSI 2025 CY - Nuremberg, Germany DA - 06.05.2025 KW - Non-destructive testing KW - Flexible sensor KW - Magnetoresistance PY - 2025 AN - OPUS4-65032 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Solodov, Dmitry T1 - Exploring the Potential of Plasma Micro-Hollow Cathode Transducers for Air-Coupled Ultrasonic Non-Destructive Testing N2 - Plasma micro-hollow cathode (MHC) transducers offer a novel and promising approach for air-coupled non-destructive testing (NDT), with the distinct capability of generating ultrasonic waves across a broad frequency spectrum. Utilizing ionized gas as the wave-emitting medium, these transducers operate without requiring any physical contact or coupling medium, making them especially attractive for testing delicate or complex surfaces. Their compact design and plasma-driven mechanism allow for flexible deployment and potential miniaturization in various testing environments. This preliminary study investigates the fundamental behavior and performance of MHC plasma transducers in the context of ultrasound-based NDT. A series of experiments were conducted using laser Doppler vibrometry and optical microphone techniques to evaluate the transducers’ ability to generate, propagate, and detect acoustic waves in different materials and geometries, including PMMA, CFRP composites, and 3D-printed PLA structures with artificial defects such as flat-bottom holes and cracks. Results reveal the ability of MHC transducers to emit high-frequency, broadband ultrasonic waves in air, suitable for detecting subsurface anomalies. Although still in the early stages of development, MHC plasma transducers show potential for advancing air-coupled ultrasonic NDT. Future work will focus on optimizing transducer geometry and operating parameters to increase efficiency and signal-to-noise ratio. While conventional linear excitation remains the primary focus, this study also briefly explores the possibility of combining MHC transducers with nonlinear resonance-based methods, such as Local Defect Resonance (LDR), to improve defect sensitivity. Although the integration of MHCs with nonlinear techniques is still a challenging prospect, there is potential for enhanced defect detection, particularly for small or weakly bonded flaws. These methods could offer higher contrast and more precise localization of defects under resonance conditions. However, the implementation of such nonlinear methods would require further research and development. This study provides a foundation for exploring the broader capabilities of plasma-based ultrasound sources in material characterization and structural health monitoring, especially in lightweight, composite, or additively manufactured materials. T2 - ICU2025 - International Congress on Ultrasonics 2025 CY - Paderborn, Germany DA - 21.09.2025 KW - Air-coupled Ultrasound KW - Non-destructive testing KW - Microhollow cathod PY - 2025 AN - OPUS4-64735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Casperson, Ralf T1 - AIFRI - Artificial Intelligence for Rail Inspection N2 - Verlegte Eisenbahnschienen werden mit Schienenprüfzügen, die mit zerstörungsfreier Ultraschall- und Wirbelstromprüftechnik ausgerüstet sind, auf Schienenfehler geprüft. Im Rahmen des mFund-geförderten Projektes AIFRI wurden von der TU Berlin KI-Algorithmen entwickelt, die die Prüfer bei der Auswertung der Daten unterstützen. Felddaten von realen Prüffahrten sind für das Training der KI ungeeignet, da es einerseits kaum Defekte in den Schienen gibt, die sich mit Ultraschall detektieren lassen, andererseits bei der Wirbelstromprüfung zahlreiche Oberflächeneffekte unbekannter Ursache angezeigt werden. Die Aufgabe der BAM bestand darin, durch Simulation gelabelte Trainingsdaten für die KI zu generieren. Während die mit simulierten Daten trainierte KI bei der Ultraschallprüfung eine gute Performance aufweist, sofern der Sim2Real-Gap durch Addition realitätsnaher Rauschsignaturen zu den simulierten Trainingsdaten minimiert wird, erwies sich die verwendete KI bei der Wirbelstromprüfung aufgrund zu vieler Falsch-Positives als ungeeignet. Die Ursache liegt vermutlich darin, dass aufgrund der großen Vielfalt von teils unbekannten Oberflächeneffekten nur eine kleine Auswahl simuliert werden konnte und die KI bei untrainierten Signalsignaturen halluziniert. T2 - AI/ML Symposium CY - Berlin, Germany DA - 06.11.2025 KW - Artificial intelligence KW - Non-destructive testing KW - Ultrasonic testing KW - Eddy current testing KW - Simulation KW - Sim2real gap KW - Railway rail inspection PY - 2025 AN - OPUS4-64630 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sobczak, Michał T1 - Badania nieniszczące materiałów z wykorzystaniem termografii laserowej z liniowym źródłem ciepła N2 - Laserowa termografia z liniowym źródłem ciepła to technika o dużym potencjale w diagnostyce materiałów konstrukcyjnych, zarówno kompozytowych, jak i metalicznych. W przeciwieństwie do metod impulsowych, skupiona linia lasera pozwala na kierunkowe wzbudzenie cieplne i precyzyjne odwzorowanie rozkładu temperatury. Przesuwanie linii względem badanej powierzchni umożliwia inspekcję dużych obszarów z wysoką rozdzielczością przestrzenną, co sprzyja wykrywaniu defektów prostopadłych do kierunku propagacji ciepła. Przedmiotem badań jest analiza odpowiedzi termicznej próbki zawierającej dwa typy nieciągłości: otwór płaskodenny (FBH) oraz szczelinę powierzchniową. Symulacje wykonano w programie Marc Mentat, z uwzględnieniem ruchu źródła ciepła i rzeczywistych parametrów materiałowych. Rozkłady temperatury analizowano dwiema metodami: rekonstrukcją pełnego termogramu oraz filtracją gradientową sumowaną w czasie (TSGF). Pierwsza z nich pozwala uzyskać obraz powierzchni próbki tak, jakby została ogrzana jednocześnie, druga wzmacnia kontrast krawędzi szczelin w kierunku prostopadłym do ruchu lasera. Omówiono także wpływ prędkości przesuwu linii lasera na skuteczność detekcji, jako parametru wpływającego na czas wzbudzenia i wrażliwość pomiaru. Dodatkowo przedstawiono wyniki pomiarów eksperymentalnych, które potwierdzają możliwość wykrywania defektów z wykorzystaniem tej metody. Uzyskane odpowiedzi cieplne stanowią uzupełnienie analizy numerycznej i potwierdzają skuteczność metody w warunkach rzeczywistych. N2 - Laser line thermography is a promising technique for the non-destructive evaluation of structural materials, including both composites and metals. Unlike conventional flash methods, a focused laser line enables directional thermal excitation and precise control over surface temperature distribution. Moving the laser line relative to the inspected surface allows testing of large areas with high spatial resolution and supports the detection of defects oriented perpendicular to the heat propagation direction. The study focuses on the thermal response of a sample containing two types of discontinuities: a flat-bottom hole (FBH), representing thickness variation or delamination, and a surface-breaking notch simulating a crack. Numerical simulations were performed in Marc Mentat, using realistic material properties and modeling the motion of the heat source. Temperature distributions were analyzed using two methods: full thermogram reconstruction and Time-Summed Gradient Filtering (TSGF). The first method reconstructs the thermal image of the entire surface as if heated simultaneously, while the second enhances contrast along temperature gradient edges perpendicular to the laser movement. The influence of laser scanning speed on temperature distribution and defect visibility is also discussed. Additionally, experimental results on a sample with an FBH confirm the method’s capability for detecting material discontinuities. The findings support the practical applicability of laser line thermography and complement the numerical analysis. T2 - 52nd Polish National Conference on Non-Destructive Testing (KKBN) CY - Wisla, Poland DA - 21.10.2025 KW - Non-destructive testing KW - Laser thermography KW - Laser line KW - Numerical simulations PY - 2025 AN - OPUS4-64484 LA - pol AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lecompagnon, Julien A1 - Rooch, Ludwig A1 - Hassenstein, Christian A1 - Ziegler, Mathias ED - Sakagami, T. ED - Inoue, H. T1 - Total Focusing in the Virtual Wave Domain: 3D Defect Reconstruction Using Spatially Structured Laser Heating N2 - Classical active thermographic testing of industrial goods has mostly been limited to generating 2D defect maps. While for surface or near-surface defect detection, this is a desired result, for deeply buried defects, a 3D reconstruction of the defect geometry is coveted. This general trend can also be well observed in widely used NDT methods (radiography, ultrasonic testing), where the progression from 2D to 3D reconstruction methods has already made profound progress (CT, UT phased array transducers). Achieving a fully 3D defect reconstruction in active thermographic testing suffers from the diffusive nature of thermal processes. One possible solution to deal with thermal diffusion is the application of the virtual-wave concept, which, by solving an inverse problem, allows the diffusiveness to be extracted from the thermographic data in the post-processing stage. What is left follows propagating-wave physics, enabling the usage of well-known algorithms from ultrasonic testing. In this work, we present our progress in the 3D reconstruction of deeply buried defects using spatially structured laser heating in conjunction with applying the well-known total focusing method (TFM) in the virtual-wave domain. T2 - 18th International Workshop on Advanced Infrared Technology and Applications (AITA 2025) CY - Kobe, Japan DA - 15.09.2025 KW - Non-destructive testing KW - Virtual wave concept KW - Laser thermography KW - Thermal thomography PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641463 DO - https://doi.org/10.3390/proceedings2025129054 VL - 129 IS - 1 SP - 1 EP - 5 PB - MDPI CY - Basel AN - OPUS4-64146 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lecompagnon, Julien T1 - Total Focusing in the Virtual Wave Domain: 3D Defect Reconstruction using spatially structured Laser Heating N2 - Classical active thermographic testing of industrial goods has mostly been limited to generating 2D defect maps. While for surface or near-surface defect detection, this is a desired result, for deeply buried defects, a 3D reconstruction of the defect geometry is coveted. This general trend can also be well observed in widely used NDT methods (radiography, ultrasonic testing), where the progression from 2D to 3D reconstruction methods has already made profound progress (CT, UT phased array transducers). Achieving a fully 3D defect reconstruction in active thermographic testing suffers from the diffusive nature of thermal processes. One possible solution to deal with thermal diffusion is the application of the virtual-wave concept, which, by solving an inverse problem, allows the diffusiveness to be extracted from the thermographic data in the post-processing stage. What is left follows propagating-wave physics, enabling the usage of well-known algorithms from ultrasonic testing. In this work, we present our progress in the 3D reconstruction of deeply buried defects using spatially structured laser heating in conjunction with applying the well-known total focusing method (TFM) in the virtual-wave domain. T2 - 18th International Workshop on Advanced Infrared Technology and Applications (AITA 2025) CY - Kobe, Japan DA - 15.09.2025 KW - Infrared thermography KW - Non-destructive testing KW - NDT KW - Total focussing method PY - 2025 AN - OPUS4-64145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Oliver T1 - More than 25 years of ink analysis non-destructive testing of black writing materials N2 - Writing inks can be divided into soluble inks and dispersion inks. Soluble inks are based on plant or insect dyes forming a water solution. In the early European Middle Ages brown plant inks were usually produced from the blackthorn bark and wine. In contrast to these soluble brown inks, one of the oldest black writing materials was produced by mixing soot with gum arabic or animal glue dissolved in a small amount of water. From Pliny’s detailed account of the manufacture of various black carbon inks, we learn that producing pure soot of high quality was not an easy task in Antiquity. Iron gall inks are a borderline case between these two groups. They are produced from four basic ingredients: gallic acid, an iron-containing component, gum arabic as a binding media, and an aqueous medium such as wine, beer, or vinegar. By mixing gallic acid with soluble iron ions, a water-soluble ferrous gallate complex is formed. Exposure to oxygen leads to the formation of insoluble black ferric gallate pigment. Due to the variety of recipes and the natural origin of raw materials, there is a wide range of different components and impurities in writing inks. The Bundesanstalt für Materialforschung und -prüfung (BAM) together with the Centre for the Study of Manuscript Cultures in Hamburg (CSMC) has developed a protocol for ink analysis. It consists of a primary screening to determine the type of the ink and a subsequent in-depth analysis using several spectroscopic techniques (X-ray fluorescence analysis and vibrational spectroscopy). This contribution presents a qualitative and quantitative analysis of historical writing inks to characterize distinguishable inks in manuscripts, to determine the origin of manuscripts, and to assign unknown fragments to time and place. T2 - Beyond the reconstruction of an Urtext: “About the history of the early Qurʾānic text with regard to digital research tools” CY - Hesse, Germany DA - 07.07.2025 KW - Archaeometry KW - Non-destructive testing KW - Material analysis KW - Cultural heritage PY - 2025 AN - OPUS4-63906 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nicolicea, Alberto A1 - Oliveros-Mata, E. S. A1 - Makarov, D. A1 - Melzer, Michael A1 - Pelkner, Matthias T1 - Flexible anisotropic magnetoresistive sensors for novel eddy current testing applications N2 - The standard method for eddy current testing (ET) of conductive materials relies on using rigid coils. In recent years magnetoresistive (MR) sensors in combination with an excitation wire have become a promising candidate for this application since it would increase the spatial resolution. New developments in flexible electronics have enabled the production of flexible sensors with the novel capability of scanning samples in conformal contact with the surface. In this article flexible anisotropic magnetoresistive (AMR) sensors were used in combination with a thin induction wire to perform eddy current testing of a curved aluminum sample with several defects imprinted on its surface. To benchmark the performance of this new method, a flat sample with reference defects of various dimensions was also scanned using flexible AMR sensors, inductive coils and rigid giant magnetoresistive (GMR) sensors. The results show that this new method of using flexible magnetic field sensors coupled with an excitation wire can easily be applied to the scanning of curved samples, while in the benchmark test employing the flat sample, the performance is not far behind more conventional techniques, with defects with depths down to 30 μm and widths down to 400 μm being detectable with an SNR of 3 (signal magnitude) and 8 (signal phase shift) at the excitation frequency of 50 kHz, and defects with depths down to 30 μm and widths down to 600 μm being detectable with an SNR of 10 (signal magnitude) and 17 (signal phase shift) at 260 kHz. KW - Magnetic field sensors KW - Flexible magnetic field sensors KW - Flexible electronics KW - Non-destructive testing KW - Eddy current testing KW - Thin film sensor fabrication KW - Defect detection KW - Magnetism PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634325 DO - https://doi.org/10.1016/j.measurement.2025.117340 SN - 1873-412X VL - 253, Part A SP - 1 EP - 15 PB - Elsevier CY - Amsterdam AN - OPUS4-63432 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kunji Purayil, Sruthi Krishna T1 - Preserving History: Application of Active Thermography for Investigating the Bücker Bü 181 Aircraft N2 - Infrared thermography is a widely recognized non-destructive testing (NDT) method used in material research and defect detection across various industrial applications. Moreover, thermography plays a crucial role in preserving cultural heritage, including historical paintings and buildings. This study focuses on the application of thermography in inspecting the historic Bücker Bü 181 aircraft, which was used in Germany during World War II. Over time, the original appearance of aircraft has often been altered as part of preservation efforts, either before or during their time in museums, leading to deviations from their historically original state. Additionally, the operational history of such objects is frequently undocumented or entirely lost, making it difficult to understand the presence of artifacts and historically significant data. These factors present major challenges in cultural heritage preservation, and destructive methods cannot be used to investigate such invaluable objects. Therefore, thermography is implemented as a non-destructive and contactless examination method. Active flash thermography combined with phase analysis is a powerful tool for evaluating multilayer systems. In this study, multiple layers of old paint on the object posed a challenge in assessing defect conditions and retrieving other critical information beneath the surface coatings. Nevertheless, pulse thermography not only demonstrated its capability to identify defects and markings in multilayered coatings but also provided insights into the internal structure and subsections of the investigated aircraft. T2 - DGZFP Jahrestagung 2025 CY - Berlin, Germany DA - 26.05.2025 KW - Non-destructive testing KW - Infrared thermography KW - Multilayer coatings KW - Cultural heritage KW - Defect detection PY - 2025 AN - OPUS4-63255 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kunji Purayil, Sruthi Krishna A1 - Hirsch, Philipp Daniel A1 - Lecompagnon, Julien A1 - Ziegler, Mathias ED - Ferrarini, Giovanni ED - López, Fernando ED - Spaeth, Peter T1 - Multispectral fusion-based crack detection using automated laser thermography inspection N2 - Crack detection of complex components is critical for maintaining the integrity and safety of structures across industries such as energy production and aerospace. The integration of multispectral imaging and automatic robot-based non-destructive testing (NDT) marks a significant advancement in the inspection of complex geometries. Multispectral imaging leverages the utilization of image data from different wavelength ranges for enhanced feature extraction and analysis. This paper proposes a novel image fusion model by combining thermal and visual images for the detection of surface and sub-surface cracks of turbine blades in energy production. Our study uses 3D scanning of components using a robot-assisted flying laser line, which measures high-resolution thermal data and RGB images using visual cameras simultaneously. Laser thermography induces a localized heating on the sample, creating a thermal response that highlights cracks and defects that are often undetectable using conventional imaging techniques. Multispectral image fusion models are developed based on an unsupervised generative adversarial network (GAN) for precise crack detection. The model validation is done using experimental data and it demonstrated high crack detection accuracy compared to conventional single-band imaging methods. This research highlights the new potential for advancing NDT technologies by combining thermal inspection techniques with optical imaging to develop a multispectral inspection approach. T2 - Thermosense: Thermal Infrared Applications XLVII CY - Orlando, Florida, United States DA - 13.04.2025 KW - Infrared imaging KW - Laser KW - Multispectral imaging KW - NDE 4.0 KW - Non-destructive testing PY - 2025 DO - https://doi.org/10.1117/12.3052496 SP - 1 EP - 11 PB - SPIE AN - OPUS4-63253 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kunji Purayil, Sruthi Krishna T1 - Multispectral fusion-based crack detection using automated laser thermography inspection N2 - Crack detection of complex components is critical for maintaining the integrity and safety of structures across industries such as energy production and aerospace. The integration of multispectral imaging and automatic robot-based non-destructive testing (NDT) marks a significant advancement in the inspection of complex geometries. Multispectral imaging leverages the utilization of image data from different wavelength ranges for enhanced feature extraction and analysis. This paper proposes a novel image fusion model by combining thermal and visual images for the detection of surface and sub-surface cracks of turbine blades in energy production. Our study uses 3D scanning of components using a robot-assisted flying laser line, which measures high-resolution thermal data and RGB images using visual cameras simultaneously. Laser thermography induces a localized heating on the sample, creating a thermal response that highlights cracks and defects that are often undetectable using conventional imaging techniques. Multispectral image fusion models are developed based on an unsupervised generative adversarial network (GAN) for precise crack detection. The model validation is done using experimental data, and it demonstrated high crack detection accuracy compared to conventional single-band imaging methods. This research highlights the new potential for advancing NDT technologies by combining thermal inspection techniques with optical imaging to develop a multispectral inspection approach. T2 - SPIE Defense+Commercial Sensing- Thermosense: Thermal Infrared Applications XLVII CY - Orlando, FL, USA DA - 13.04.2025 KW - Non-destructive testing KW - Infrared imaging KW - NDE 4.0 KW - Multispectral imaging KW - Laser PY - 2025 AN - OPUS4-63050 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yagdjian, H. A1 - Lecompagnon, Julien A1 - Hirsch, Philipp Daniel A1 - Ziegler, Mathias A1 - Gurka, M. T1 - Application of the thermal shock response spectrum (TSRS) methodology to various forms of heat sources by pulse thermography and comparison by using a rotating line scan contour search algorithm N2 - In this paper, we propose a novel contour search algorithm (CSA) for image processing. Its efficacy is evaluated through a comparative analysis with established techniques such as Canny Edge and Snakes: Active contour models, utilizing infrared thermography (IRT) images. Based on the new CSA, we investigate the influence of different pulse shapes on the IRT post-processing methodology, particularly focusing on the thermal shock response spectrum (TSRS), using two different heat sources: xenon flash lamps and a laser. Moreover, this allows for a more precise quantitative comparison of the TSRS with existing IRT post-processing techniques, including pulse phase thermography and thermal signal reconstruction, concerning the detection of defects in composite materials, particularly in carbon fiber-reinforced polymer. A quantitative comparison was performed using the Tanimoto criterion and signal-to-noise ratio. A more detailed analysis is conducted to identify inherent limitations and potential benefits of the new TSRS methodology. We further investigate and experimentally confirm our previous finding on the qualitative correlation between the one-dimensional thermal N-layer model and test data from the TSRS optimization process for defect determination. This correlation can eliminate the time-consuming optimization step, making TSRS a more attractive alternative to common IRT methods and enhancing the quantitative description of defects. KW - Thermography KW - Non-destructive testing KW - NDT KW - Defect identification KW - Laser KW - Contour search PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615056 DO - https://doi.org/10.1063/5.0232015 SN - 1089-7550 VL - 136 IS - 175101 SP - 1 EP - 20 PB - AIP Publishing AN - OPUS4-61505 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Friedrich, Alexander T1 - Simulation data for eddy current rail testing - simulation accuracy and evaluation uncertainty quantification N2 - This dataset serve to quantify the simulation error and the evaluation uncertainties in the context of eddy current rail testing. It was obtained during the AIFRI project (Artificial Intelligence for Rail Inspection) with the Faraday software by INTEGRATED Engineering Software, using its BEM Solver. KW - Non-destructive testing KW - Eddy current testing KW - Eddy current simulstion PY - 2024 DO - https://doi.org/10.5281/zenodo.13970374 PB - Zenodo CY - Geneva AN - OPUS4-61470 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lay, Vera A1 - Baensch, Franziska A1 - Skłodowska, Anna A1 - Fritsch, Tobias A1 - Stamm, Michael A1 - Prabhakara, Prathik A1 - Johann, Sergej A1 - Sturm, Patrick A1 - Kühne, Hans-Carsten A1 - Niederleithinger, Ernst T1 - Multi–sensory Monitoring and Non–destructive Testing of New Materials for Concrete Engineered Barrier Systems N2 - The crucial part of nuclear waste storage is the construction of sealing structures made of reliable, safe and well–understood materials. We present an extended analysis of long-term multi–sensory monitoring and non–destructive testing (NDT) inspection of two laboratory specimens aiming at potential materials for sealing structures for nuclear waste repositories. Specimens with a volume of 340 litres made from newly developed alkali–activated materials (AAM) and established salt concrete (SC) were analysed using embedded acoustic emission and wireless radio-frequency identification (RFID) sensors, ultrasonic echo imaging, active thermography, and X–ray computed tomography. The monitoring analysis showed lower heat of reaction and 50% less acoustic emission events in AAM compared to SC. However, due to the surface effects of the AAM material, the number of acoustic emission events increased significantly after approximately two months of monitoring. Subsequently performed NDT inspections reliably located embedded sensors and confirmed the absence of major cracks or impurities. The presented laboratory results show the feasibility and potential of comprehensive NDT monitoring and inspection to characterise cementitious and alternative materials as well as the need for multi–parameter long–term monitoring. Thus, our study demonstrates that tailored NDT investigations will help to develop safe sealing structures for nuclear waste repositories. KW - Radioactive waste KW - Barrier KW - Concrete KW - AAM KW - Non-destructive testing PY - 2024 DO - https://doi.org/10.3151/jact.22.516 SN - 1347-3913 VL - 22 IS - 9 SP - 516 EP - 529 PB - Japan Concrete Institute AN - OPUS4-61461 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maillard, S. T1 - Development of Active Thermography for NDT applications through standardization N2 - Many laboratories have been working about Active Thermography as a Non Destructive Testing method for many years. This method can be applied on metallic or composites materials for surface or subsurface defects. Thus, many different configurations can be encountered to measure the heat distribution and generate heat flow into the part. Signal processing is also widely used to improve the performance of detection. After encouraging results, aerospace, automotive and energy industries are now involved into industrialization of the technology to apply it for production or maintenance applications. Good practices and common wording are often required by end-user to qualify the process. Since the beginning of the 2000s, a working group was founded within CEN/TC138 'Non-destructive Testing' to define standards in thermography, in the European Committee for Standardization (CEN). Some other actors have also produced standards (ISO, IEC, ASTM...). This paper aims to list the standards currently available about thermography and the associatd vocabulary. It describes the generic terms to be used in active and passive thermography (operating modes, reference blocks, reporting…) and also more specific elements about laser and induction thermography for example. It will also put in perspective the further works to be done in the next few years to take into account the new trends in active thermography and how to qualify for industrial applications. T2 - 17th Quantitative InfraRed Thermography Conference - QIRT 2024 CY - Zagreb, Croatia DA - 01.07.2024 KW - Infrared Thermography KW - Non-destructive testing KW - Standardization PY - 2024 AN - OPUS4-60931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maillard, S. T1 - Development of Active Thermography for NDT applications through standardization N2 - Many laboratories have been working about Active Thermography as a Non Destructive Testing method for many years. This method can be applied on metallic or composites materials for surface or subsurface defects. Thus, many different configurations can be encountered to measure the heat distribution and generate heat flow into the part. Signal processing is also widely used to improve the performance of detection. After encouraging results, aerospace, automotive and energy industries are now involved into industrialization of the technology to apply it for production or maintenance applications. Good practices and common wording are often required by end-user to qualify the process. Since the beginning of the 2000s, European Committee for Standardization (CEN) has launched a Working Group within CEN/TC138 to define standards in thermography. Some other actors have also produced standards (ISO, IEC, ASTM,..). This goal of this presentation is to present a status of the standard currently available about thermography and the associated vocabulary. It describes the generic terms to be used in active and passive thermography (operating modes, reference blocks, reporting,…) and also more specific elements about laser and induction thermography for example. It will also put in perspective the further works to be done in the next few years to take into account the new trends in active thermography and how to qualify for industrial applications. T2 - 20th World Conference on Non-Destructive Testing (20th WCNDT) CY - Incheon, South Korea DA - 27.05.2024 KW - Infrared Thermography KW - Non-destructive testing KW - Standardization PY - 2024 AN - OPUS4-60913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chaudhuri, Somsubhro T1 - Fatigue damage detection using Lock-In Thermography N2 - Early detection of fatigue cracks and accurate measurements of the crack growth play an important role in the maintenance and repair strategies of steel and composite structures exposed to cyclic loads during their service life. Commonly used non-destructive techniques such as strain gauges, clip gauges, ultrasound, etc. used for detection and monitoring of fatigue damage are contact-based and perform local measurements. In addition, complex full-field techniques are commonly investigated, such as digital image correlation (DIC) and infrared thermography (IRT). In this work, a specific implementation of IRT, called lock-in IRT, is implemented for fatigue damage detection. This technique evaluates the thermal stress response of test specimens, specifically focusing or “locking-in” on the frequency of applied cyclic loads. Three different test scenarios are presented. First, a section of a wind turbine rotor blade made of a glass fibre reinforced plastic (GFRP) shell structure under cyclic load was examined with Lock-In IRT along with DIC. The primary advantage of Lock-In IRT in this test setup was that it required no sample preparation, as compared to the painting and speckle pattern required for DIC. In the frequency domain, specifically the frequency of applied cyclic load, it was possible to extract local directional inhomogeneous loading within the shell structure due to progressive damage, confirmed with the deformation obtained from DIC results. Second, thick welded specimens made of structural steel S355 were subjected to multiple NDT methods such as strain gauges, crack luminescence penetration (developed specifically at BAM), ultrasound, and IRT, with the aim of investigating the ability of each technique to detect fatigue damage initiation as early as possible in the total fatigue life of the specimen. Amongst the range of implemented techniques, Lock-In IRT provided the first indication of fatigue crack initiation at the weld toe of the specimens. This was validated with the other techniques as well as fractography. Third, steel S355 specimens used to manufacture offshore wind turbine monopiles were tested. The specimens were extracted from a plate that was submerged in a marine environment, resulting in a corroded surface with corrosion pits. These specimens were subjected to cyclic tensile loads without removing the corrosion pits. The fatigue tests were monitored using IRT in a special full-field capturing setup that enables both sides of the specimen to be examined with one IRT camera. This allowed the entire pitted surface to be monitored for fatigue damage initiation at the same time. With the implementation of Lock In IRT, the surface stress distribution could be captured (the stress concentration at the pits), and fatigue crack initiation could be detected and linked with specific corrosion pits. T2 - 20th World Conference on Non-Destructive Testing CY - Incheon, South Korea DA - 27.05.2024 KW - Non-destructive testing KW - Thermografie KW - Thermal stress analysis KW - Fatigue testing KW - Damage detection PY - 2024 AN - OPUS4-60697 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chaudhuri, Somsubhro T1 - Passive infrared thermography as an inspection tool for operational wind turbine rotor blades N2 - The growing wind energy infrastructure presents a significant challenge in the maintenance and operation of wind turbines (WT) and their intricate components. An important aspect of WT maintenance is the inspection of wind turbine rotor blades (WTB) to ensure the overall health and safety of the turbine. This inspection process involves both visual and mechanical examinations of the blades to identify any indicators of damage or wear that could compromise their performance and, consequently, the structural integrity of the entire WT system. The complexity of WTBs is compounded by their ever-expanding dimensions, exceeding 100 meters in length for 16 MW WT systems, and their multi-material composition. Within this context, passive infrared thermography emerges as a potential alternative to conventional contact- or proximity-based inspection methods. Unlike active thermography, passive thermography uses solar radiation and ambient temperature variation for thermal contrast, eliminating the need for traditional heat lamps, flash, or laser-based techniques. A novel inspection method has been developed to semi-autonomously assess wind turbine blades (WTBs) while the wind turbine (WT) is operational, from ground level. This approach leverages optimal thermal contrast, which depends on prevailing weather conditions during field measurements, enabling the visualization of both external and internal features of the WTBs through post-processing techniques. In this study, thermal data obtained through passive thermography is compared with contemporaneous visual imagery to definitively classify observed features in thermal images as either surface or sub-surface features. This analysis, coupled with corresponding weather conditions, provides valuable insights into the capabilities and limitations of the inspection technique. Additionally, finite-element-based (FE) thermal simulations of a WTB section are employed to parametrically assess the influence of weather conditions, beyond those observed during field measurements, based on a validated model. In addition, the thermal images also consist of thermal signatures of leading-edge turbulence due to possible leading-edge erosion in WTBs. These are primarily vortices, and their shape and size depend on the morphology of the damage as well as the rotational speed of the WTBs. The inspections are accompanied by automatic data evaluation of the thermal signatures. To improve the precision of erosion damage identification, a fully convolutional network (FCN) is employed, trained, and tested using over 1000 annotated thermographic blade images. Additionally, the study introduces strategies for grouping smaller damage indications and simplification rules based on realistic thermal imaging resolutions. As leading-edge erosion could potentially lead to annual energy production (AEP) losses, this technique could prove to be a powerful tool in establishing the presence of damage and the resulting AEP loss. T2 - 20th World Conference on Non-Destructive Testing CY - Incheon, South Korea DA - 27.05.2024 KW - Non-destructive testing KW - Thermografie KW - Wind turbine rotor blades KW - Windenergie Anlage Rotorblätter KW - Thermography PY - 2024 AN - OPUS4-60695 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Küttenbaum, Stefan A1 - Kainz, C. A1 - Braml, T. ED - Matos, J.C. T1 - Non-destructively Measurable Quantities Relevant to Reliability Assessment of Existing Concrete Bridges – Case Studies N2 - In reliability assessment of existing bridges, collected information about the structure can be utilized to modify partial safety factors and to refine characteristic values individually. In this way, uncertainties covered in initial calculation models and arising from assumptions can be reduced as well as biases identified and corrected. This allows for more realistic assessments and more appropriate decisions on actions to be taken. However, the on-site observation of information is generally associated with certain costs. For this reason, an efficient data-supported reassessment requires that only the individually relevant testing tasks are solved. Additional sensitivity analyses can further be used to specify the requirements on certain inspections, such as the testing result quality to be achieved, in order to avoid too imprecise or too expensive measurements on-site. In this contribution, the methodology for the demand-actuated definition of measurement objectives is demonstrated using the example of non-destructive concrete testing methods and findings from reassessments of two prestressed concrete bridges. Each case study includes the semi-probabilistic identification of structural weak points in ultimate and serviceability limit states, a comparison with respective probabilistic sensitivity analyses, and the subsequent derivation of parameters that are a) measurable and b) highly relevant in the individual reliability analyses. KW - Reliability KW - Assessment KW - Existing structures KW - Non-destructive testing PY - 2024 SN - 978-3-031-60270-2 DO - https://doi.org/10.1007/978-3-031-60271-9_18 VL - 494 SP - 209 EP - 219 PB - Springer CY - Cham AN - OPUS4-60613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bahrami Eskandari, Ardalan A1 - Küttenbaum, Stefan T1 - NDT Data-Supported Structural Reassessments based on Regression Relations in Measuring Data Analysis N2 - Non-destructive Testing (NDT) provides valuable data about structural elements, supporting the assessment of existing infrastructures without incurring additional structural damage from inspections. Simultaneously, the uncertainty in measurement, which quantifies the quality of measurement results, plays a crucial role in decisions aimed at, e.g., optimizing maintenance strategies, rehabilitation works and Structural Health Monitoring (SHM) implementations. The Guide to the Expression of Uncertainty in Measurement (GUM) framework has already been considered for non-destructive concrete testing. Regarding that, extensive measurements with sophisticated scopes need to be conducted by experts as an obligatory process. This study illustrates how NDT results describing the inner structure of a concrete element can effectively support the reassessment of bridges in operation. To achieve this, the study considers the various measurable positions of the resisting longitudinal tendons of a bridge structure to investigate the displacement change under dynamic service loads. Furthermore, this study aims to simplify and optimize existing NDT data analysis procedures by employing regression analysis, enabling the detection of structural features. This regression analysis yields a modifier for determining the correct depth of an object within the structural element. The method is validated through laboratory experiments, including the use of an ultrasonic measurement system. As a result, it provides unbiased and accurately measured results, while ensuring that the measurement data can remain uncorrelated. Major advantages include efficient computation, a wider scope, and avoiding redundant information about the measuring process. The findings demonstrate that employing the proposed NDT analysis method, with its enhanced practicability, can significantly augment the efficiency of NDT data-supported structural reassessments across various scenarios. T2 - EWSHM 2024 CY - Potsdam, Germany DA - 10.06.2024 KW - Existing structures KW - Non-destructive testing KW - Practicality measurement KW - Bridge reassessment KW - Statistical analysis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604825 DO - https://doi.org/10.58286/29714 SN - 1435-4934 SP - 1 EP - 9 PB - NDT.net AN - OPUS4-60482 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nicolicea, Alberto A1 - Oliveros-Mata, E. S. A1 - Zabila, Y. A1 - Makarov, D. A1 - Melzer, Michael A1 - Pelkner, Matthias T1 - Flexible anisotropic magnetoresistive sensors for novel magnetic flux leakage testing capabilities N2 - Rigid magnetic field sensors such as anisot Hall sensors have been used for years and have become industry standard for electromagnetic non-destructive testing (NDT). Recent technological developments in the field of flexible electronics allow for the fabrication of reshapeable magnetic field sensors on flexible substrates via thin-film deposition or printing. The magnetic properties of these sensors have comparable characteristics to industry-standard rigid magnetic field sensors, with the added ability of adapting to the surface of complex components and scanning in contact with the sample surface. This improves defect detectability and magnetic signal strength by minimizing the scanning lift-off (LO) distance. In this article flexible AMR sensors mounted on a rotative mechanical holder were used to scan a semi-circular ferromagnetic sample with 3 reference defects via magnetic flux leakage (MFL) testing, thus demonstrating the applicability of this type of sensors for the scanning of curved samples. In order to benchmark the performance of these sensors in comparison to industry standard rigid magnetic field sensors, a ferromagnetic sample with 10 reference defects of different depths was scanned employing flexible AMR and rigid GMR sensors. Defects with depths ranging from 110 μm up to 2240 μm were detected with an signal-tonoise ratio (SNR) of 2.7 up to 27.9 (for flexible AMR sensors) and 6.2 up to 72.3 (for rigid GMR sensors), respectively. A 2D magnetometer mapping of the sample with a spatial scanning step of 10 × 50 μm2 (flexible AMR) and 16 × 100 μm2 (rigid GMR) was obtained. The results show that this type of sensor can be used for high-resolution and high-detail mapping of defects on the surface of planar and non-planar ferromagnetic samples since the scanning lift-off distance is equal to the substrate thickness of 20 μm for in-contact scanning. The SNR comparison between flexible and rigid sensors shows that the performance of the flexible AMR sensors employed is not very far behind the performance of the rigid GMR sensors used. KW - Flexible magnetic field sensors KW - Non-destructive testing KW - Magnetic flux leakage KW - Thin film sensor fabrication KW - Defect detection PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603931 DO - https://doi.org/10.1016/j.ndteint.2024.103160 SN - 0963-8695 VL - 146 SP - 1 EP - 15 PB - Elsevier CY - Amsterdam AN - OPUS4-60393 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Popiela, Bartosz T1 - Non-Destructive Testing of Type 4 Composite Pressure Vessels N2 - Non-Destructive Testing (NDT) of type 4 composite pressure vessels can be seen as key to better understanding the behaviour of the composite structure and the impact of the manufacturing process on its quality. In this presentation, NDT methods used in the “Trustworthy Hydrogen” project are introduced. A brief discussion of the observed phenomena is provided. T2 - Visit of a delegation from Korea Fire Institute (KFI) CY - Berlin, Germany DA - 24.06.2024 KW - Composite KW - Pressure vessel KW - Non-destructive testing PY - 2024 AN - OPUS4-60401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barretto, T. A1 - Gentes, S. A1 - Braun, J. A1 - Averin, Anton A1 - Lecompagnon, Julien A1 - Stroncik, N. T1 - Automated non-destructive internal corrosion detection on radioactive drums (ZIKA) N2 - The aim of the ZIKA research project, funded by the BMBF funding program FORKA (FKZ:15S9446 A-C), is the automated detection of internal corrosion of radioactive drums using non-destructive testing (NDT). The newly gained findings will be combined with research results from the previous project EMOS (FKZ:15S9420), which dealt with the external damage of drums. Using NDT, internal corrosion and possible internal sources of damage can be identified before they become a safety-relevant issue. However, if internally sourced damages can be seen externally, the integrity of the damaged drum is no longer guaranteed, which has significant consequences. Therefore, early detection before integrity failure is of particular importance for interim storage facilities with low- and medium-level radioactive waste drums. T2 - Kerntechnik 2024 CY - Leipzig, Germany DA - 11.06.2024 KW - Corrosion detection KW - Non-destructive testing KW - Automated inspection system PY - 2024 SP - 1 EP - 5 AN - OPUS4-60322 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Timofeev, Juri A1 - Azari, H. A1 - Satyanarayana, R. T1 - Controlled Creating of Delaminations in Concrete for Nondestructive Testing N2 - Locating and sizing delaminations is a common inspection task in the maintenance and quality control of construction and rehabilitation. Their detection is an important area of application of nondestructive testing in civil engineering (NDT-CE). To improve this application, NDT test systems and test solutions must be compared, for which specimens containing well-defined delaminations are needed to serve as a reference. Currently, there are no widely accepted procedures available for creating such flaws locally and reproducibly. This study presents procedures for creating artificial delaminations repeatably and as close as possible to natural delaminations. To produce the discontinuities only substances were used which can occur in concrete components and do not affect the application of NDT-CE methods. Ultrasonic pulse-echo (UPE) was used to test the flaws in the specimens. The delaminations were created by applying expansive mortar in prepared through holes. Three specimens with two delaminations each were built and tested using UPE. KW - Concrete KW - Reference KW - Delamination KW - Test specimen KW - Non-destructive testing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595201 DO - https://doi.org/10.1007/s10921-023-01044-7 SN - 0195-9298 VL - 43 IS - 1 SP - 1 EP - 13 PB - Springer Science and Business Media LLC AN - OPUS4-59520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bühling, Benjamin A1 - Maack, Stefan A1 - Strangfeld, Christoph T1 - Fluidic Ultrasound Generation for Non‐Destructive Testing N2 - AbstractAir‐coupled ultrasonic testing (ACU) is a pioneering technique in non‐destructive testing (NDT). While contact testing and fluid immersion testing are standard methods in many applications, the adoption of ACU is progressing slowly, especially in the low ultrasonic frequency range. A main reason for this development is the difficulty of generating high amplitude ultrasonic bursts with equipment that is robust enough to be applied outside a laboratory environment. This paper presents the fluidic ultrasonic transducer as a solution to this challenge. This novel aeroacoustic source uses the flow instability of a sonic jet in a bistable fluidic switch to generate ultrasonic bursts up to 60 kHz with a mean peak pressure of 320 Pa. The robust design allows operation in adverse environments, independent of the operating fluid. Non‐contact through‐transmission experiments are conducted on four materials and compared with the results of conventional transducers. For the first time, it is shown that the novel fluidic ultrasonic transducer provides a suitable acoustic signal for NDT tasks and has potential of furthering the implementation of ACU in industrial applications.This article is protected by copyright. All rights reserved KW - Aeroacoustics KW - Air-coupled ultrasound KW - Fluidics KW - Harsh environment KW - Laser Doppler vibrometer KW - Non-destructive testing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594273 DO - https://doi.org/10.1002/adma.202311724 SN - 0935-9648 SP - 1 EP - 14 PB - Wiley AN - OPUS4-59427 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Ballio, F. A1 - Chatzi, E. A1 - Cigada, A. A1 - Darò, P. A1 - Elfgren, L. A1 - Gentile, C. A1 - Górski, M. A1 - Küttenbaum, Stefan A1 - Limongelli, M. P. A1 - Mancini, G. A1 - Oliveira, S. A1 - Rasol, M. A1 - Schmidt, F. A1 - Shan, J. A1 - Sousa, H. A1 - Torrent, R. A1 - Ueda, T. A1 - Verstrynge, E. T1 - Chapter 6: Case studies N2 - This chapter contains a selection of case studies that show the implementation of the methods and tools that have been described in the previous chaprters of fib Bulletin 109 on actual large-scale structures. KW - Structural engineering KW - Structural Health Monitoring KW - Non-destructive testing KW - Static and dynamic reassessment KW - Existing structures PY - 2023 SN - 978-2-88394-172-4 DO - https://doi.org/10.35789/fib.BULL.0109.Ch06 SN - 1562-3610 VL - fib Bulletin 109 SP - 104 EP - 126 PB - Fédération internationale du béton (fib) CY - Lausanne AN - OPUS4-59341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Bartolac, M. A1 - Bien, J. A1 - Górski, M. A1 - Keßler, S. A1 - Küttenbaum, Stefan A1 - Kuzawa, M. A1 - Ley, J. A1 - Maack, Stefan A1 - Mendler, A. A1 - Ryjáček, P. A1 - Santos, L. A1 - Verstrynge, E. ED - Keßler, S. ED - Limongelli, M. P. ED - Apostolidi, E. T1 - Chapter 2: Condition survey - Testing and monitoring methods N2 - The through-life management of our constantly ageing infrastructure is a basic requirement in order to ensure their structural safety and serviceability. Each structure experiences deterioration processes with time leading to a decrease of structural safety and serviceability. The design of new structures considers the expected deterioration for a defined period, the design service life. However, a frequent survey of structural safety controlling structural condition should be mandatory and a maintenance plan should be an integral part of the design. In addition, many structures have exceeded their design service life already or are very close to it leading to an increasing demand for condition assessment. On the one hand, assumptions made during design are not valid any more due to change of the loads, e.g., increasing traffic loads in terms of number and weights. On the other hand, design codes evolved over time in such a way that existing structures do not comply with today’s standards. In all these cases, the through-life management is an important tool to maintain the accessibility of existing structures with known reliability. In line with the new Model Code for Concrete Structures, which includes guidance for both – design of new structures and assessment of existing structures, the Task Group 3.3 focused on the compilation of a state-of-the-art guideline for the through-life management of existing concrete structures, including: Data acquisition by testing and monitoring techniques; Condition assessment for the evaluation of existing structures; Performance prediction using advanced methods; Decision-making procedures to perform a complete assessment of existing structure. The overall objective of the through-life management is the assessment of the current condition and the estimation of the remaining service life under consideration of all boundary conditions. KW - Life management KW - Concrete KW - Non-destructive testing KW - Structural health monitoring KW - State-of-the-art PY - 2023 UR - https://doi.org/10.35789/fib.BULL.0109 SN - 978-2-88394-172-4 DO - https://doi.org/10.35789/fib.BULL.0109.Ch02 SN - 1562-3610 VL - fib Bulletin 109 SP - 16 EP - 38 PB - Fédération internationale du béton (fib) CY - Lausanne AN - OPUS4-59110 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barzegar, M. A1 - Lugovtsova, Yevgeniya A1 - Bulling, Jannis A1 - Mishurova, Tatiana A1 - Pasadas, D. A1 - Ribeiro, A. A1 - Ramos, H. T1 - Automatic improved-resolution imaging of composite adhesive joints using time-frequency-wavenumber filtering applied to ultrasonic guided wavefields N2 - This paper presents an automatic damage imaging technique by employing a signal processing approach based on applying hierarchically clustered filters across different domains. The technique involves time-frequency-wavenumber filter banks which are applied sequentially to ultrasonic guided wave (UGW) data. The study is conducted for a single lap joint composite specimen with a special focus on small voids which were formed due to manual adhesive component mixing. UGW data are acquired with a 3D Scanning Laser Doppler Vibrometer (LDV) over the scan area of the bonded plate. UGWs are excited at the central frequency of 100 kHz by a single piezoelectric transducer mounted on the surface of the single plate. Within each domain of time, frequency, and wavenumber, four filters are designed which results in 64 distinct filtered wavefields. From each filtered wavefield, an image is obtained by using root-mean-square (RMS) calculation of the signals. The obtained results are then combined to create a final, improved-resolution image of the scan area. The final image is compared to the image obtained through RMS calculation of full wavefield with interpolation through Delaunay triangulation and the image obtained by X-ray radiography. The results show that the smallest void that could be detected has a diameter of 2.14 mm. T2 - 2023 IEEE International Ultrasonics Symposium (IUS) CY - Montreal, QC, Canada DA - 03.09.2023 KW - Adhesive joints KW - Ultrasonic guided waves KW - Laser Doppler vibrometer KW - Damage imaging KW - Non-destructive testing KW - Porosity analysis PY - 2023 DO - https://doi.org/10.1109/IUS51837.2023.10307423 SP - 1 EP - 4 PB - IEEE AN - OPUS4-58795 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stamm, Michael T1 - Semi-automated detection of rain erosion damages on turbine blades with passive thermography and AI image processing N2 - The European Green Deal and the global fight against climate change call for more and larger wind turbines in Europe and around the world. To meet the increasing demand for maintenance and inspection, partly autonomous methods of remote inspection are increasingly being developed in addition to industrial climbers performing the inspection. Rotor blades are exposed to extreme weather conditions throughout their lifetime of 20 years, and the leading edge erodes over time. These erosion damages change the aerodynamic features of blades and can cause structural damages. The estimated annual energy production (AEP) losses caused by erosion damages are between 0.5% and 2% per year. The classification of the severity of a rain erosion damage and the quantification of the resulting AEP losses for cost efficient repair and maintenance efforts and improved power production of wind turbines are subject of scientific research. For the inspection of wind turbine rotor blades, passive thermography is an option that has been used to detect both internal damage [3, 4] as well as erosion on the surface [5, 6]. The advantage is that, given suitable boundary conditions, not only the rain erosion damage itself but also temperature differences caused by the resulting turbulences can be observed on the surface of the blade. Turbulences reduce the efficiency of the rotor blades and result in AEP losses. Optimised thermography inspections can contribute to detect and to evaluate rain erosion damages. The thermal inspection lasts 10 minutes per turbine and is performed while the turbine is in full operation, avoiding downtime and lost opportunities for the turbine owner which are usually caused by conventional blade inspections. The timely inspection procedure is complemented by an automatic data evaluation and results in a considerable number of inspected wind turbines in a certain period of time. A fully convolutional network (FCN) is implemented for the automated evaluation of thermal images. In the presented study, more than 1000 thermographic images of blades were annotated, augmented and used to train and test the FCN. The aim is the precise marking of thermal signatures caused by erosion damage at the leading edge. The area size of the detected temperature difference caused by turbulences was used to identify and categorise damages. Certain strategies were adopted to group small individual indications as one large damage, in order to develop simplification rules based on realistic thermal imaging resolution. T2 - Wind Energy Science Conference (WESC) 2023 CY - Glasgow, Scotland DA - 23.05.2023 KW - Non-destructive testing KW - Thermography KW - Wind turbine blade PY - 2023 AN - OPUS4-58498 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Küttenbaum, Stefan T1 - Guideline on NDT-supported reliability assessment of existing structures N2 - The presentation summarizes the idea and the methodology of the ZfPStatik project and gives insight into three case studies, showing how non-destructive testing results can be utilized beneficially in the recalculation of existing prestressed concrete and reinforced concrete bridges. T2 - 2nd Conference of the European Association on Quality Control of Bridges and Structures – EUROSTRUCT2023 CY - Vienna, Austria DA - 26.09.2023 KW - Reliability KW - Assessment KW - Existing structures KW - Non-destructive testing PY - 2023 AN - OPUS4-58485 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Küttenbaum, Stefan A1 - Braml, T. A1 - Heinze, M. A1 - Kainz, C. A1 - Keuser, M. A1 - Kotz, P. A1 - Lechner, T. A1 - Maack, Stefan A1 - Reinke, K.-D. A1 - Schulze, S. A1 - Soukup, A. A1 - Stettner, C. A1 - Taffe, A. A1 - Wöstmann, Jens T1 - Guideline on NDT-supported reliability assessment of existing structures - Current developments in Germany N2 - Information about an existing structure can be collected at certain costs to evaluate the reliability and condition as realistically as necessary. This information can be relevant or irrelevant, true or biased, precise or imprecise. The incorporation of relevant and quality-assessed measured information into reliability reassessment offers the chance to extend remaining lifetimes and support decision making about optimal actions or maintenance strategies. This paper shows recent developments in a national research project that aims to produce a guideline on the NDT-based, structure-specific modification of partial safety factors. The general methodology, results from recalculations according to the Eurocodes and metrologically solvable testing tasks relevant in the recalculation of the concrete bridges are shown and compared with the non-destructive testing methods applicable to concrete bridges. A case study is used to demonstrate that as-built drawings, in this case of the positions of tendons and shear reinforcement, can be verified using the radar method. KW - Non-destructive testing KW - Concrete bridges KW - Partial safety factor modification PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584862 DO - https://doi.org/10.1002/cepa.2168 SN - 2509-7075 VL - 6 IS - 5 SP - 537 EP - 543 PB - Ernst & Sohn CY - Berlin AN - OPUS4-58486 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Küttenbaum, Stefan A1 - Kainz, C. A1 - Braml, T. T1 - Reliability assessment of existing concrete bridges with geometrical NDT results - Case studies N2 - The results of and the validity in reliability assessment of existing bridges essentially depend on the information available about the considered system. Information about the actual condition as well as structural and material characteristics can be observed on-site to refine the computation models used in assessment. Non-destructive testing (NDT) methods for concrete structures are capable of reconstructing missing, questioned, or inconsistent as-built plans. This contribution summarizes recent developments within the scope of the national pre-standardization project “ZfPStatik”, which aims to prepare a guideline about NDT-supported structural analyses. The focus is on the purposeful and explicit utilization of geometrical tendon and reinforcement bar positions (measured on-site using the ultrasound echo and ground penetrating radar (GPR) techniques) in probabilistic reliability analyses — shown by means of real case studies. The well-established first order reliability method is applied to different concrete bridges, which are typical for the German road bridge stock, to demonstrate the utility of incorporating quality-evaluated NDT-results in terms of changes in structural reliability. T2 - 13th German-Japanese Bridge Symposium CY - Osaka, Japan DA - 28.08.2023 KW - Non-destructive testing KW - Prestressed concrete KW - Data-informed reliability analysis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582727 SP - 29 EP - 40 PB - Osaka Metropolitan University CY - Osaka AN - OPUS4-58272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Trappe, Volker T1 - Scarf-joint repairs under fatigue loading investigated for sandwich shell applications N2 - Wind turbine rotor blades are produced as aerodynamic, three-dimensionally formed sandwich shell structures using mainly glass fiber reinforced plastics (GFRP). The GFRP used today have the potential to withstand the harsh operating conditions of rotor blades over the projected service life of 20 years. Premature damages that occur can be traced primarily back to design and/or manufacturing imperfections, as well as unusually high load scenarios (for instance lightning strikes, or strong winds combined with system control errors). Therefore, rotor blades have to be repaired several times (on average 2-3 times) during their projected service life. Approximately 70% of these are repairs of small- to medium-sized sandwich shells, carried out by technicians directly accessing the blade by suspended roping at the wind turbine location. The goal is to execute repairs that will last over the remaining service life, i.e. be sustainable. Within the framework of a research project carried out at BAM, Division 5.3 Polymer Matrix Composites, Department 5 for Materials Engineering, not only was the geometric shape (round vs. square in relation to the top view) varied, but also the layup of the scarf repair structure, variables that have not been studied systematically to-date. Sub-component scale sandwich shell specimens with representative repairs were used in this work in addition to coupon-scale specimens that are more commonly seen in literature. These sub-component shell specimens were tested using a unique shell test bench under loading conditions representative of wind turbine blade shell operating conditions with respect to fatigue strength. Using non-destructive testing methods (field strain measurement and thermography), damage development and distribution was monitored and analyzed in-situ. As a result, a concept was developed in which the repaired areas showed at least equivalent if not higher fatigue strength than the reference shells that were not repaired. T2 - ICFC9 - The 9th International Conference on the Fatigue of Composites CY - Vicenza, Italy DA - 21.06.2023 KW - Repair of sandwich shell structures KW - Non-destructive testing KW - Wind turbine blades PY - 2023 AN - OPUS4-57929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dayani, Shahabeddin T1 - Quantification of Deep Discharge Mechanism in a Li-Ion Battery by operando X-ray Computed Tomography N2 - Lithium-ion batteries connected in series are prone to an electrical abuse called over discharge. We present a comprehensive investigation of the over discharge abuse mechanism in lithium-ion batteries using operando non-destructive imaging. The study focuses on understanding the behavior of copper dissolution and deposition during over discharge, which can lead to irreversible capacity loss and internal short circuits. By utilizing synchrotron X-ray computed tomography (SXCT), the concentration of dissolved and deposited copper per surface area is quantified as a function of depth of discharge (DoD). T2 - HZB user meeting CY - Berlin, Germany DA - 22.06.2023 KW - Non-destructive testing PY - 2023 AN - OPUS4-57793 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maack, Stefan A1 - Küttenbaum, Stefan A1 - Bühling, Benjamin A1 - Borchardt-Giers, Kerstin A1 - Aßmann, Norman A1 - Niederleithinger, Ernst T1 - Low frequency ultrasonic pulse-echo datasets for object detection and thickness measurement in concrete specimens as testing tasks in civil engineering N2 - The dataset contains raw data gathered with the ultrasonic pulse-echo method on concrete specimens. The surfaces of the measuring objects were automatically scanned point by point. Pulse-echo measurements were performed at each of these measuring points. The test specimens represent two typical testing tasks in construction industry: the detection of objects and the determination of dimensions to describe the geometry of components. By automating the measurement process, the different test scenarios are examined with a high repeatability, precision and measuring point density. Longitu- dinal and transversal waves were used and the geometrical aperture of the testing system was varied. The low-frequency probes operate in a range of up to approximately 150 kHz. In addition to the specification of the geometrical dimensions of the individual probes, the directivity pattern and the sound field characteristics are provided. The raw data are stored in a universally readable format. The length of each time signal (A-scan) is two milliseconds and the sampling rate is two mega-samples per second. The provided data can be used for comparative studies in signal analysis, imag- ing and interpretation as well as for evaluation pur- poses in different, practically relevant testing scenarios. KW - Validation KW - Puls-echo method KW - Ultrasonic KW - Non-destructive testing KW - SAFT KW - Reconstruction algorithm PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575185 DO - https://doi.org/10.1016/j.dib.2023.109233 SN - 2352-3409 VL - 48 SP - 1 EP - 16 PB - Elsevier Inc. AN - OPUS4-57518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dayani, Shahabeddin A1 - Markötter, Henning A1 - Schmidt, Anita A1 - Widjaja, Martinus Putra A1 - Bruno, Giovanni T1 - Multi-level X-ray computed tomography (XCT) investigations of commercial lithium-ion batteries from cell to particle level N2 - Adopting X-ray computed tomography (XCT) for ex-situ characterization of battery materials has gained interest in the past decade. The main goal of this paper is to demonstrate the effectiveness of several X-ray computer tomography techniques to study commercial batteries. General guidelines are provided to select the most suitable imaging equipment and parameters for investigations of lithium-ion batteries, spanning the length scales from cell to electrode, down to particle level. Relevantly, such parameters would also be suitable for operando experiments. Safety mechanisms and manufacturing inconsistencies at cell level as well as defects and inhomogeneity in cathode and anode is illustrated and quantified. Furthermore, relation of beam energy and sample-detector-distance on contrast retrieved from attenuation and phase shift is inspected using Synchrotron XCT. KW - Non-destructive testing KW - X-ray computed tomography KW - Synchrotron X-ray computed tomography KW - Lithium-ion battery PY - 2023 DO - https://doi.org/10.1016/j.est.2023.107453 SN - 2352-152X VL - 66 SP - 107453 PB - Elsevier Ltd. AN - OPUS4-57512 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Gebauer, D. A1 - Gutierrez, B. A1 - Marx, S. A1 - Maack, Stefan A1 - Küttenbaum, Stefan A1 - Pirskawetz, Stephan A1 - Breit, W. A1 - Mechtcherine, V. A1 - Grahl, K. A1 - Thiel, T. A1 - Schickert, M. A1 - Krüger, M. T1 - Interrelated data set from nondestructive and destructive material testing of concrete compressive strength specimens N2 - This data set contains three different data types obtained from concrete specimens. For each specimen, the rebound numbers, ultrasonic data (ultrasonic velocity, time of flight), and destructive concrete strength are given. Two kind of specimen geometries were tested: cubes and drilled cores. The files are labeled according to the specimen geometry as "cube" or "core" and the type of measurement data as "compressive_strength", "rn_R" and "rn_Q" for rebound numbers as well as "us" for ultrasonic data. The ultrasonic data were generated by six independent laboratories, the rebound numbers by five independent laboratories and the destructive tests by one laboratory. The designation of each specimen establishes the relationship between the different data types. KW - Non-destructive testing KW - Rebound number KW - Ultrasonic pulse velocity KW - Compressive concrete strength KW - Interlaboratory comparison PY - 2023 DO - https://doi.org/10.7910/DVN/AFCITK PB - Harvard College CY - Cambridge, MA, USA AN - OPUS4-57499 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Alexander T1 - The AIFRI Project - Artificial Intelligence For Rail Inspection N2 - The rails of modern railways face an enormous wear and tear from ever increasing train speeds and loads. This necessitates diligent non-destructive testing for defects of the entire railway system. Non-destructive testing of rail tracks is carried out by rail inspection trains equipped with ultrasonic and eddy current test devices. However, the evaluation of the gathered data is mainly done manually with a strong focus on ultrasonic data, and defects are checked on-site using hand-held testing equipment. Maintenance measures are derived based on these on-site findings. The aim of the AIFRI project (Artificial Intelligence For Rail Inspection) is to - increase the degree of automation of the inspection process, from the evaluation of the data to the planning of maintenance measures, - increase the accuracy of defect detection, - automatically classify detected indications into risk classes. These aims will be achieved by training a neural network for defect detection and classification. Since the current testing data is unbalanced, insufficiently labeled and largely unverified we will supplement fused, simulated eddy current and ultrasonic testing data in form of a configurable digital twin. T2 - PostDoc Day 2022 CY - Berlin, Germany DA - 03.11.2022 KW - Non-destructive testing KW - Artificial intelligence KW - Simulation KW - Eddy current KW - Ultrasound PY - 2022 AN - OPUS4-57240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Azari, H. A1 - Shams, S. A1 - Köpp, Christian A1 - Timofeev, Juri A1 - Niederleithinger, Ernst T1 - Development of reference specimens for nondestructive evaluation of concrete bridge decks N2 - Decades of non-destructive evaluation (NDE) for the quality assurance of concrete bridges revealed the necessity of developing procedures for building reference specimens for different defects. External objects have been widely used in specimen construction to represent defects. However, embedded materials can alter the actual defect characteristics, interrupting the NDE responses. This study proposes new approaches to fabricating reference specimens for reinforced concrete that feature substantial defects, including cracks, delamination, honeycombing and rebar corrosion, without external objects. As a result, realistic responses can be acquired to identify promising NDE methods for characterising actual deteriorations. The procedures were produced with the intent of being reproducible in any laboratory. Destructive and non-destructive testing methods were performed to verify the effectiveness of the processes in creating defects. This study provides research laboratories with techniques for fabricating reference specimens for characterising defects and assessing the performance of NDE technologies. KW - Concrete structures KW - Reference KW - Specimen KW - Non-destructive testing KW - Laboratory tests PY - 2023 DO - https://doi.org/10.1680/jfoen.21.00030 SN - 2043-9911 SP - 1 EP - 12 PB - ICE Publishing AN - OPUS4-56957 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scherr, J. F. A1 - Kollofrath, J. A1 - Popovics, J. S. A1 - Bühling, Benjamin A1 - Grosse, C. U. T1 - Detection of Delaminations in Concrete Plates Using a Laser Ablation Impact Echo Technique N2 - This study investigates the non-destructive detection of delaminations in concrete plates using non-contact laser ablation, instead of the conventional hammer excitation, as part of the impact echo method. We performed tests on five concrete specimens of different sizes, two of which contained artificial delaminations. A range of steel ball hammers was used as reference impulse sources, the responses of which were compared with wave excitation generated by a 7 ns pulsed 1064 nm Nd:YAG laser with 150 mJ pulse energy. Signals were recorded by surface-mounted accelerometers and two contactless methods: microphones and a laser Doppler vibrometer. The laser generates frequencies across a broad range of frequencies (0 to 150 kHz) but with much less energy than the hammers' narrower frequency spectra; the laser pulse energy transferred into the specimen is 0.07 mJ, corresponding to about 0.5 ‰ of the impulse source energy. Because of this, the thick intact plates' characteristic thickness stretch resonance frequency can be reliably detected by the hammer excitations but not when using laser excitation. However, the laser can excite low-frequency flexural vibration modes over a shallow delamination at 3 cm depth. The low-frequency flexural vibration results are verified by numerical natural frequency analysis. KW - Concrete testing KW - Defect detection KW - Lamb waves KW - Impact echo KW - Non-destructive testing KW - Vibration PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567932 DO - https://doi.org/10.1007/s10921-022-00921-x SN - 0195-9298 VL - 42 IS - 1 SP - 1 EP - 14 PB - Springer AN - OPUS4-56793 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Melzer, Michael T1 - Flexible GMR sensors for novel flux leakage testing capabilities N2 - In order to detect small and hidden material defects or micro-cracks, weak and localized magnetic stray fields need to be detected and characterized on the magnetic surface. Current flux leakage sensor elements are rigid and rely on air gaps to detect stray fields several hundred micrometers above the surface. Furthermore, the increasing complexity of critical components, enabled by novel fabrication technologies, primarily additive manufacturing, poses a significant challenge to the available flux leakage testing technologies. The emergence of flexible magneto-electronics paves the way to a compliant form of magnetic sensors that, on one hand, are able to adapt to highly curved surfaces, allowing these measurements to be conducted on irregularly formed components, which are inaccessible for nowadays electromagnetic NDT equipment and, on the other hand, could enhance the detection limit for small magnetic stray fields, by allowing the magneto-sensitive elements to approximate the object’s surface until only a few µm, mediated by thin and flexible packaging. T2 - 38th Danubia-Adria Symposium on Advances in Experimental Mechanics CY - Poros, Greece DA - 20.09.2022 KW - Non-destructive testing KW - Flux leakage testing KW - Flexible sensorics KW - GMR Sensors KW - Flexible electronics PY - 2022 AN - OPUS4-56628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -