TY - CONF A1 - Bruno, Giovanni T1 - Absorption and refraction tomography: characterization and non-destructive testing of micro-structured materials N2 - The combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread holds equally for industrial and academic research, and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing. Examples of micro-structured inhomogeneous materials will be given, such as Composites, Ceramics, Concrete, and Additively manufactured parts. I will also show how X-ray refraction computed tomography (CT) can be highly complementary to classic absorption CT, being sensitive to internal interfaces. T2 - Treffen der `Confindustria´(Industrieverband) CY - Potenza, Italien DA - 29.03.2016 KW - Tomographie KW - Refraktion KW - Neutronenbeugung KW - Additive Fertigung PY - 2016 AN - OPUS4-35700 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Absorption and refraction tomography: Characterization and non-destructive testing of micro-structured materials N2 - The combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread equally holds for industrial and academic research, and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing. Examples of micro-structured inhomogeneous materials will be given, such as Composites, Ceramics, Concrete, and Additively manufactured parts. I will also show how X-ray refraction computed tomography (CT) can be highly complementary to classic absorption CT, being sensitive to internal interfaces. Additionally, I will present a new technique in our portfolio, Neutron Diffraction, which is extremely well suited to the study of internal stresses, both residual and under external load. T2 - Kolloquium ICMCB Bordeaux CY - Bordeaux, France DA - 13.07.2017 KW - Computed tomography KW - X-ray refraction KW - Neutron diffraction KW - Additive manufacturing KW - Ceramics KW - Composites KW - BAM PY - 2017 AN - OPUS4-41041 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Mechanical and thermal properties of aluminum titanate (AT) N2 - In this seminar I present the microstructure and micromechanical properties of diesel particulate filter materials, and then particularize them to porous microcracked aluminum titanate. I show that neutron diffraction is particularly suited for bulk studies, especially under applied load or at high temperatures. The combination of macroscopic and microscopic tests with modeling and simulation yields great added value to understand the mechanics of microcracking. T2 - Webinar DFG Hotmix CY - Online meeting DA - 14.06.2021 KW - Imaging KW - Neutron and X-ray Diffraction KW - Non-linear stress-strain KW - Anisotropy KW - Microcracking KW - Porosity PY - 2021 AN - OPUS4-52838 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni A1 - Gollwitzer, Christian T1 - XCT discloses the Impact of Machining on Mechanical Properties of Diesel Particulate Filter Materials N2 - Microstructural changes in porous cordierite for diesel particulate filter applications caused by machining were characterized using microtensile testing and X-ray computed tomography (XCT). Young’s modulus was determined on ~215-380 m thick machined samples by digital image correlation. Results show a decrease of Young’s modulus due to machining of the thin samples. Explanation of this phenomenon was provided by XCT: the presence of debris due to machining and the variation of porosity due to removal of the outer layers were quantified and correlated with the introduction of further microcracking. T2 - ICT Conference 2018 CY - Wels, Austria DA - 06.02.2018 KW - Diesel Particulate Filter Materials KW - Mechanical Properties PY - 2018 AN - OPUS4-44778 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Morphological and crystallographic Anisotropy in porous ceramic N2 - In this talk, the morphological (pore space) and crystallographic (domain) anisotropy of porous ceramics fordiesel particulate filter applications are discussed. The influence of such microstructural feature on the macroiscopic properties at componnt level is also shown. T2 - MSCA Webinar CY - Online meeting DA - 05.12.2024 KW - Neutron Diffraction KW - Porosity KW - X-ray Computed Tomography KW - X-ray refraction radiography KW - Large Scale facilites PY - 2024 AN - OPUS4-62047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - How 3D X-ray Imaging and Residual Stress Analysis contribute to safety of materials and structures N2 - The safety of materials and structures can be detrimentally influenced by residual stresses (RS) and defect populations (voids or other features leading to failure) if they are not correctly accounted for in the design. Therefore, the accurate characterization of these features and the consideration of their impact is crucial for the safe design of components. The ability to characterize these features non-destructively enables the direct correlation on resulting mechanical performance. 3D X-ray computed tomography (XCT) is used to resolve and quantitively analyze microstructural features (i.e., voids, porosity). This is often used to assess the capability of the manufacturing route, i.e., additive manufacturing (AM). The non-destructive nature of the method also enables the study of the evolution of damage in materials from such microstructural features [1]. Using in-situ methods such as compression or tension, the propagation of damage from initial microstructure can be assessed, aiding our understanding of which features are detrimental to safety [3]. Diffraction based residual stress analysis methods including high energy X-ray and neutron diffraction can be used to study the residual stress gradients from the surface, subsurface and into the bulk non-destructively. These methods can be used to study the influence of heat treatments on residual stress and can be combined with XCT results to correlate the interaction of residual stresses with microstructural features (i.e., void clusters). This talk will give an overview of the capabilities and opportunities of 3D XCT and diffraction based residual stress analysis to close the gap in our understanding of material degradation on mechanical performance, enabling manufacturers to adjust their designs accordingly for safety critical applications. A particular focus will be made on examples where the two advanced techniques are combined to enhance such understanding. T2 - MaterialsWeek 2025 CY - Frankfurt am Main, Germany DA - 02.04.2025 KW - Neutron Diffraction KW - Residual Stress KW - X-ray Computed Tomography KW - Additive Manufacturing KW - Large Scale facilites KW - Creep KW - Defects KW - BAMline PY - 2025 AN - OPUS4-62895 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - X-ray Absorption and Refraction techniques for characterization and non-destructive-testing of materials N2 - The combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread equally holds for industrial and academic research and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing. Examples of micro-structured inhomogeneous materials will be given, such as Composites, Ceramics, Concrete, and Additively manufactured parts. I will also show how X-ray refraction computed tomography (CT) can be highly complementary to classic absorption CT, being sensitive to internal interfaces. Additionally, I will show how Neutron Diffraction, which is extremely well suited to the study of internal stresses, both residual and under external load, can well be coupled to the microstructural framework gained by CT, allowing understanding the microstructure-property relationships in materials. T2 - ENSAM CY - Paris, France DA - 28.11.2019 KW - Additive Manufacturing KW - Computed Tomography KW - Neutron Diffraction KW - X-ray refraction techniques KW - Composites PY - 2019 AN - OPUS4-49927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishurova, Tatiana A1 - Bruno, Giovanni T1 - BAM activities in material characterization by advanced X-ray imaging N2 - The overview of the activity of Federal Institute for Material Research and Testing (BAM, Belin, Germany) in the field of additively manufacturing material characterization will be presented. The research of our group is focused on the 3D imaging of AM materials by means of X-ray Computed Tomography at the lab and at synchrotron, and the residual stress characterization by diffraction (nondestructive technique). Also, two successful research project in collaboration with CAM2, Sweden are presented. T2 - CAM2 Annual Meeting CY - Gothenburg, Sweden DA - 25.10.2023 KW - Additive manufacturing KW - Residual stress KW - X-ray computed tomography PY - 2023 AN - OPUS4-58828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - X-Ray absorption, refraction, and diffraction techniques for the characterization and non-destructive testing of materials N2 - The combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread equally holds for industrial and academic research and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing. Examples of micro-structured inhomogeneous materials will be given, such as Composites, Ceramics, Concrete, and Additively manufactured parts. I will also show how X-ray refraction computed tomography (CT) can be highly complementary to classic absorption CT, being sensitive to internal interfaces. Additionally, I will show how Neutron Diffraction, which is extremely well suited to the study of internal stresses, both residual and under external load, can well be coupled to the microstructural framework gained by CT, allowing understanding the microstructure-property relationships in materials. T2 - VDI FA101- Anwendungsnahe zerstörungsfreie Werkstoff und Bauteilprüfung Jährliches Treffen CY - Berlin, Germany DA - 10.04.2025 KW - Neutron Diffraction KW - X-ray computed tomography KW - Large Scale Facilities KW - X-ray refraction radiography KW - BAMline PY - 2025 AN - OPUS4-62939 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishurova, Tatiana A1 - Evsevleev, Sergei A1 - Mehta, B. A1 - Nyborg, L. A1 - Virtanen, E. A1 - Markötter, Henning A1 - Hryha, E. A1 - Bruno, Giovanni T1 - Failure Mechanisms Investigation by Means of in-situ Synchrotron Computed Tomography in Aluminum MMC-based Alloy Tailored for Additive Manufacturing (AM) N2 - The availability of high-performance Al alloys in AM is limited due to difficulties in printability, requiring both the development of synergetic material and AM process to mitigate problems such as solidification cracking during laser powder bed fusion (LPBF). The goal of this work was to investigate the failure mechanism in a LPBF 7017 Aluminium alloy + 3 wt% Zr + 0.5 wt% TiC. The processing leads to different categories of Zr-rich inclusions, precipitates and defects. T2 - Alloys for Additive Manufacturing Symposium 2022 (AAMS22) CY - Munich, Germany DA - 11.09.2022 KW - Additive manufacturing KW - Laser powder bed fusion KW - Synchrotron X-ray computed tomography KW - MMC PY - 2022 AN - OPUS4-56110 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni A1 - Kupsch, Andreas A1 - Serrano-Munoz, Itziar T1 - Absorption and refraction tomography: Characterization and Non-destructive Testing of Micro-structured Materials N2 - The combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread holds equally for industrial and academic research, and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing. I will also show how X-ray refraction computed tomography (CT) can be highly complementary to classic absorption CT, being sensitive to internal interfaces. T2 - MPA Seminar 2024 CY - Stuttgart, Germany DA - 08.10.2024 KW - X-ray Refaction radiography KW - X-ray computed tomography KW - Damage KW - Composites KW - Large Scale facilites KW - Synchrotron PY - 2024 AN - OPUS4-61347 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - X-ray refraction 2D and 3D techniques N2 - X-ray refraction techniques represent a very promising, yet not so wide-spread, set of X-ray techniques based on refraction effects. They allow determining internal specific surface (surface per unit volume) in a non-destructive fashion, position and orientation sensitive, and with nanometric detectability. While they are limited by the X-ray absorption of the material under investigation, we demonstrate showcases of ceramics and composite materials, where understanding of microstructural features could be achieved in a way unrivalled even by high-resolution techniques such as electron microscopy or computed tomography. T2 - ICTMS 2017 CY - Lund, Sweden DA - 26.06.2017 KW - X-ray refraction KW - Composites KW - Damage KW - Cracks KW - Cearmics PY - 2017 AN - OPUS4-41042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Absorption and refraction tomography: Characterization and Non-destructive Testing of Micro-structured Materials N2 - The combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread holds equally for industrial and academic research, and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated. T2 - Meeting Digital Image and Volume Correlation CY - Milton Keynes, UK DA - 29.02.2016 KW - Non-destructive KW - Characterization KW - Zerstörungsfreie Prüfung PY - 2016 AN - OPUS4-35749 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Introduction to Residual Stress N2 - The determination of residual stress in additively manufactured materials is a challenge, even after decades from the establishment of the basics of residual stress analysis. This is due to the peculiar microstructure of such materials. In fact, researchers have discovered that conventional methods for the determination of RS in materials do not properly work for AM materials. In this tutorial, the basics of RS analysis will be explained, together with the basics of AM manufacturing techniques. The microstructure of the peculiar materials (AM) dealt with here will be elucidated. Successively, the necessary modifications to the conventional approaches to RS analysis will be explained and case studies will be displayed, for the attendant to touch with hands the peculiarities of the approaches. Finally, a few experimental and theoretical tips will be given on dos and don’ts for a correct determination of RS in AM materials. T2 - 11th European Conference on Residual Stresses (ECRS-11) CY - Prague, Czech Republic DA - 03.06.2024 KW - Neutron Diffraction KW - Residual Stress KW - Mechanical Properties KW - X-ray diffraction PY - 2024 AN - OPUS4-60422 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni A1 - Jaenisch, Gerd-Rüdiger A1 - Bellon, Carsten A1 - Jaczinski, Jessica T1 - Virtual XCT - Simulation of Industrial XCT-Systems with aRTist N2 - One of the few 3D methods, that can be used to analyze an object non-destructively, is X-ray computed tomography (CT). The determination of the object's deviations, such as shape and the internal structure of objects, including defects and material degradation, is of particular interest to industry. The ability of CT to scan an object with its internal and external features at once causes increasing adoption in dimensional metrology. This includes the need to determine the measurement uncertainty. Experimental uncertainty determination by conducting repeated CT measurements is costly and time-consuming. The simulation of the CT measurement process offers the possibility of determining the task-specific measurement uncertainty numerically in a resource-efficient manner. There are already several software programs available that simulate CT systems, such as aRTist. Once the virtual replica of a CT system has been completed, it’s accuracy must be evaluated quantitively in comparison to the CT measurements. To focus on analyzing the quality of the simulated CT images different metrics are introduced for the comparison of experimental and simulated CT projections. The results of the comparisons are presented, and conclusions are drawn how to improve the simulation of industrial CT systems. T2 - MPA Seminar 2024 CY - Stuttgart, Germany DA - 08.10.2024 KW - X-ray Computed tomography KW - Simulations KW - Virtual XCT KW - Digital Twin PY - 2024 AN - OPUS4-61346 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - BAM Characterization on Capabilities in Additive Manufacturing N2 - Quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing, with particular focus on additively manufactured materials. I will also show how X-ray refraction computed tomography (CT) and Neutron diffraction can be highly complementary to classic absorption CT, being sensitive to internal interfaces and residual stress analysis, respectively. T2 - Treffen des Konsortium AeroMatForAM CY - Köln, Germany DA - 16.03.2017 KW - Neutronenbeugung KW - Eigenspannungen KW - Additive Fertigung KW - Computertomographie KW - Röntgenrefraktion KW - X-ray Refraction KW - Additive Manufacturing KW - Computed Tomography KW - Residual Stress analysis KW - Neutron Diffraction PY - 2017 AN - OPUS4-39657 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cabeza, S. A1 - Bruno, Giovanni T1 - Damage evolution of Al matrix 4-phase composite N2 - The evolution of the microstructure of multiphase metal matrix composite AlSi12CuNiMg with 7% vol. Al2O3 + 15% vol. SiC (short fibers and whiskers, respectively) was studied by synchrotron computed tomography. It comprehended as cast and after heat treatment conditions, as well as damage evaluation after ex-situ compression tests at room temperature. The volume fraction of different phases, their distribution, their orientation, and damage events are studied. The influence on mechanical properties of the orientation of the planar random short fibres Al2O3 towards loading was investigated. Phase-specific load partition analysis for samples with fiber plane parallel and orthogonal to load, respectively, was performed by means of neutron diffraction (ND) during in-situ compression tests at room temperature. ND results proved that damage occurrence in the fillers strongly depends on the preferential orientation of those, playing a crucial role in the failure of the sample. The computed tomography observations confirm the damage observations from curves of load partition analysis of each phase. T2 - FiMPART 2017 CY - Bordeaux, France DA - 9.7.2017 KW - Composites KW - Aluminium matrix KW - Neutron diffraction KW - Computed tomography PY - 2017 AN - OPUS4-41109 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - X-ray Computed Tomography: Facts and Myths N2 - In this talk, I will describe the principle of Computed Tomography, explain its mathematical fundaments, show the artefacts occurring during data acquisition and give examples of applications. T2 - Chalmers Annual Meeting 2024 CY - Gothenburg, Sweden DA - 23.10.2024 KW - X-ray Computed tomography KW - Defects KW - Machine Learning KW - Reconstruction KW - Artefacts KW - Synchrotron PY - 2024 AN - OPUS4-61514 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Capabilities at BAM, division 8.5- X-ray Imaging N2 - The X-ray computed tomography capabilities at BAM (especially in Division 8.5) are shown. It is also shown that the group possesses X-ray refraction radiography techniques, which are complementary to absorption radiography, and uses diffraction for residual stress analysis. Examples of applications in the field of Additive Manufacturing ale also shown. T2 - DGM AK XCT CY - Berlin, Germany DA - 27.11.2024 KW - X-ray Computed tomography KW - Defects KW - X-ray refraction radiography KW - Additive Manufacturing PY - 2024 AN - OPUS4-62046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Starting new adventures at BAM. The focus area projects PROMOAM and AGIL N2 - While additive manufacturing (AM) is blossoming in nearly every industrial field, and the most different process are being used to produce components and materials, little attention is paid on the safety concerns around AM materials and processes. Leveraging on our leading expertise in non-destructive testing (NDT) and materials characterization, we approach AM at BAM under two important viewpoints: first the on-line monitoring of the process and of the product, second the evolution of the (unstable) microstructure of AM materials under external loads. These two subjects are the core of the two new-born internal projects ProMoAM and AGIL, respectively. A detailed view of the goals and the organization of these two projects will be given, together with the expected output, and some preliminary results. T2 - Vortragsveranstaltung Bauhaus Universität, im Rahmen der Kolloquien der Fakultät Bauwesen. CY - Weimar, Germany DA - 01.06.2018 KW - Thermography KW - Additive Manufacturing KW - Non-destructive testing KW - On-line monitoring KW - Residual stress PY - 2018 AN - OPUS4-45118 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni A1 - Fritsch, Tobias A1 - Schröder, Jakob A1 - Mishurova, Tatiana A1 - Ulbricht, Alexander A1 - Evans, Alexander A1 - Serrano-Munoz, Itziar T1 - How to experimentally determine residual stress in AM structures N2 - The experimental determination of residual stress becomes more complicated with increasing complexity of the structures investigated. Unlike the conventional and most of the additive manufacturing (AM) fabrication techniques, laser powder bed fusion (PBF-LB) allows the production of complex structures without any additional manufacturing step. However, due to the extremely localized melting and solidification, internal stress-induced deformation and cracks are often observed. In the best case, significant residual stress is retained in the final structures as a footprint of the internal stress during manufacturing. Here we report solutions to the most prevalent challenges when dealing with the diffraction-based determination of residual stress in AM structures, in particular the choice of the correct diffraction elastic constants. We show that for Nickel-based alloys, the diffraction elastic constants of AM material significantly deviate from their conventional counterparts. Furthermore, measurement strategies to overcome the hurdles appearing when applying diffraction-based techniques to complex-shaped lattice structures are presented: a) proper sample alignment within the beam, b) the proper determination of the residual stress field in a representative part of the structure (i.e., with an engineering meaning). Beyond the principal stress magnitude, the principal direcions of residual stress are discussed for different geometries and scan strategies, as they are relevent for failure criteria. We show that the RS in the lattice struts can be considered to be uniaxial and to follow the orientation of the strut, while the RS in the lattice knots is more hydrostatic. Additionally, we show that strain measurements in at least seven independent directions are necessary for the correct estimation of the principal stress directions. The measurement directions should be chosen according to the sample geometry and to an informed choice on the possible strain field (i.e., reflecting the scan strategy). We finally show that if the most prominent direction is not measured, the error in the calculated stress magnitude increases in such a manner that no reliable assessment of RS state can be made. T2 - Additive 2024 CY - Berlin, Germany DA - 12.06.2024 KW - Neutron Diffraction KW - Residual Stress KW - X-ray Computed Tomography KW - Additive Manufacturing KW - Lattice Structure KW - Inconel PY - 2024 AN - OPUS4-60423 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Absorbtion and Refraction Techniques: Characterization and Non-Destructive Testing of Additively Manufactured Materials N2 - The combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread holds equally for industrial and academic research, and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing. Examples of micro-structured inhomogeneous materials will be given, such as Composites, Ceramics, Concrete, and Additively manufactured parts. I will also show how X-ray refraction computed tomography (CT) can be highly complementary to classic absorption CT, being sensitive to internal interfaces. T2 - c-Kolloquium an dem FRM II Reaktor CY - Munich, Germany DA - 29.07.2016 KW - Computertomographie KW - Metrologie KW - 3D Mikrostruktur KW - Zerstörungsfreie Prüfung KW - Röntgenrefraktion KW - TF Material KW - Analytical Science PY - 2015 AN - OPUS4-38827 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eddah, Mustapha A1 - Markötter, Henning A1 - Mieller, Björn A1 - Widjaja, Martinus Putra A1 - Beckmann, Jörg A1 - Bruno, Giovanni T1 - Multi-energy high dynamic range synchrotron X-ray computed tomography N2 - Synchrotron X-ray computed tomography (SXCT) is regularly used in materials science to correlate structural properties with macroscopic properties and to optimize manufacturing processes. The X-ray beam energy must be adapted to the sample properties, such as size and density. If both strongly and weakly absorbing materials are present, the contrast to the weakly absorbing materials is lost, resulting in image artifacts and a poor signal-tonoise ratio (SNR). One particular example is a low-temperature co-fired ceramics (LTCC), in which metal connections are embedded in a ceramic matrix and form 3-dimensional conducting structures. This article describes a method of combining SXCT scans acquired at different beam energies, significantly reducing metal artifacts, and improving image quality. We show how to solve the difficult task of merging the scans at low and high beam energy. Our proposed merging approach achieves up to 35 % improvement in SNR within ceramic regions adjacent to metallic conductors. In this way, previously inaccessible regions within the ceramic structure close to the metallic conductors are made accessible. The paper further discusses methodological requirements, limitations, and potential extensions of the presented multi-energy SXCT merging technique. KW - Synchrotron computed tomography KW - Reconstruction algorithm KW - High dynamic range KW - Data merging KW - Low-temperature cofired ceramics PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652339 DO - https://doi.org/10.1016/j.tmater.2025.100079 SN - 2949-673X VL - 9 SP - 1 EP - 10 PB - Elsevier CY - Amsterdam AN - OPUS4-65233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Orientation of pore space in diesel particulate filter materials N2 - Porous ceramic diesel particulate filters (DPFs) are extruded products that possess macroscopic anisotropic mechanical and thermal properties. This anisotropy is caused by both morphologic features (mostly the orientation of porosity) and crystallographic texture. We systematically studied those two aspects in a cordierite and two aluminum titanate (AT) ceramic materials of different porosity using mercury porosimetry, gas adsorption, electron microscopy, X-ray diffraction, and X-ray refraction radiography. We found that a lower porosity in AT content implies a larger isotropy of both the crystal texture and the porous space orientation. We also found that, analogous to cordierite, AT crystallites do align with their axis of negative thermal expansion along the extrusion direction. However, unlike what found for cordierite, the aluminium titanate crystallite form is such that a more pronounced (0 0 2) texture along the extrusion direction implies porosity aligned perpendicular to it. T2 - 6th Cellular Materials CellMAT 2020 CY - Online meeting DA - 07.10.2020 KW - Microstructure-property relations KW - Preferred orientation KW - X-ray refraction KW - Pore orientation KW - Crystal structure KW - Extrusion PY - 2020 AN - OPUS4-51451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eddah, Mustapha A1 - Markötter, Henning A1 - Mieller, Björn A1 - Widjaja, Martinus Putra A1 - Beckmann, Jörg A1 - Bruno, Giovanni T1 - Multi-Energy High Dynamic Range (HDR) Synchrotron X-ray Computed Tomography applied to LTCC samples N2 - Synchrotron X-ray computed tomography (SXCT) is regularly used in materials science to correlate structural properties with macroscopic properties and to optimize manufacturing processes. The X-ray beam energy must be adapted to the sample properties, such as size and density. If both strongly and weakly absorbing materials are present, the contrast to the weakly absorbing materials is lost, resulting in image artifacts and a poor signal-to-noise ratio (SNR). One example is a low-temperature co-fired ceramics (LTCC), in which metal connections are embedded in a ceramic matrix and form 3-dimensional conducting structures. This article describes a method of combining SXCT scans acquired at different beam energies, significantly reducing metal artifacts, and improving image quality. We show how to solve the difficult task of merging the scans at low and high beam energy. Our proposed merging approach achieves up to 35% improvement in SNR within ceramic regions adjacent to metallic conductors. In this way, previously inaccessible regions within the ceramic structure close to the metallic conductors are made accessible. The paper further discusses methodological requirements, limitations, and potential extensions of the presented multienergy SXCT merging technique. T2 - iCT 2026 CY - Linz, Austria DA - 10.02.2026 KW - Synchrotron x-ray CT KW - Multi-energy CT KW - Low-Temperature cofired ceramics PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655848 SP - 1 EP - 7 CY - e-Journal of Nondestructive Testing AN - OPUS4-65584 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Procedures for quantitative characterization of periodic minimal surface structures (TMPSS) N2 - Additively manufactured (AM) triply periodic metallic minimum surface structures (TPMSS, from the English Triply Periodic Minimum Surface Structures) fulfill several requirements in both biomedical and engineering fields: tunable mechanical properties, low sensitivity to manufacturing defects, mechanical stability, and high energy absorption. However, they also present some quality control challenges that may prevent their successful application. In fact, optimization of the AM process is impossible without considering structural features such as manufacturing accuracy, internal defects, and surface topography and roughness. In this study, quantitative nondestructive analysis of Ti-6Al-4V alloy TPMSS was performed using X-ray computed tomography (XCT). Several new image analysis workflows are presented to evaluate the effects of buildup direction on wall thickness distribution, wall degradation, and surface roughness reduction due to chemical etching of TPMSS. It is shown that the fabrication accuracy is different for the structural elements printed parallel and orthogonal to the fabricated layers. Different strategies for chemical etching showed different powder removal capabilities and thus a gradient in wall thickness. This affected the mechanical performance under compression by reducing the yield stress. A positive effect of chemical etching is the reduction of surface roughness, which can potentially improve the fatigue properties of the components. Finally, XCT was used to correlate the amount of powder retained with the pore size of the TPMSS, which can further improve the manufacturing process. T2 - MSE 2022 CY - Darmstadt, Germany DA - 27.09.2022 KW - Surface roughness KW - Additive manufacturing KW - Computed tomography KW - Wall thickness KW - Machine learning KW - Manufacturing defects PY - 2022 AN - OPUS4-56162 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Engineering applications of neutrons at the ILL: retrospective, present, and future N2 - In this talk, the evolution of the demand for engineering applications of neutrons at the ILL in the last 10 years is presented. It is shown that small angle neutron scattering and diffraction are highly demanded by the materials science community. Further development in the field is foreseen, with the use of in-situ (furnace, tension/compression rig, humidity cells, etc.) techniques to associate to the neutron techniques. T2 - ILL 100th Scientific Council CY - Grenoble, France DA - 09.04.2019 KW - Neutron Diffraction KW - Residual Stress KW - Small Angle Neutron Scattering KW - Engineering applications KW - Institut Laue Langevin PY - 2019 AN - OPUS4-48396 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Applications of X-ray refraction to non-destructive characterization of ceramics and composites N2 - X-ray refraction is analogous to visible light deflection by matter, with two main differences: 1- convex objects cause divergence (i.e., the refraction index n is smaller than 1), and 2- deflection angles are very small, from a few seconds to a few minutes of arc (i.e., n is near to 1). Trivially but importantly, deflection of X-rays is also sensitive to the orientation of the object boundaries. These features make X-ray refraction techniques extremely suitable to a) detect defects such as pores and microcracks, and quantify their densities in bulk (light) materials, and b) evaluate porosity and particle properties such as orientation, size, and spatial distribution (by mapping). While X-ray refraction techniques cannot in general image single defects, their detectability is simply limited by the wavelength of the radiation. We will thereby show the application of X-ray refraction 2D mapping (topography) and tomography to different sorts of problems in ceramic science and technology: 1) Sintering of SiC green bodies; 2) Porosity analysis in diesel particulate filter silicates; 3) fiber de-bonding in metal and polymer matrix composites; 4) micro-cracking of glass-precursor -eucryptite. We will see that the use of X-ray refraction analysis yields quantitative results, also directly usable in available models. T2 - FiMPART 2017 CY - Bordeaux, France DA - 09.07.2017 KW - Refraction radiography KW - Ceramics KW - Refraction tomography KW - Composites PY - 2017 AN - OPUS4-41040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Léonard, Fabien A1 - Hasenfelder, Uta A1 - Krebs, Holger A1 - Bruno, Giovanni T1 - Assessment of shock tube systems by synchrotron X-ray computed tomography N2 - Shock tube systems are non-electric explosive fuses employed in blasting and demolition applications to trigger the detonation of explosive charges. Their working principle is based on the explosive reaction of a fine explosive powder on the tubing's inner surface, generating a shock wave traveling at a velocity of 2,100 m/s along the length of the tube, without destroying it. One of the key aspects of the manufacturing process of these shock tubes is the size and morphology of the explosive powder grains and their distribution on the inner wall of the tube, in order to propagate the shockwave efficiently and reliably. For the first time, synchrotron X-ray computed tomography has been used to characterize non-destructively the explosive powder grains, typically Al/HMX between 10 and 20 μm in size, in terms of morphology and 3D distribution but also to characterise the presence and location of defects within the shock tube walls. KW - Explosives KW - Nonel KW - Shock wave KW - Blasting KW - Energetic systems PY - 2017 UR - http://www.ndt.net/events/iCT2017/app/content/Paper/61_Leonard.pdf SP - 1 EP - 7 CY - Leuven, Belgium AN - OPUS4-39345 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Léonard, Fabien A1 - Zhang, Zhen A1 - Krebs, Holger A1 - Bruno, Giovanni T1 - Morphological characterisation of explosive powders by XCT: When grain numbers count N2 - Ammonium nitrate (AN) prills are commonly used as an ingredient in industrial explosives and in fertilisers. Conventional techniques (such as BET or mercury intrusion porosimetry) can measure the open porosity and specific surface area of AN prill, but the closed porosity is not obtainable. This work was focused on evaluating X-ray computed tomography (XCT) as a non-destructive technique for the assessment of porosity in AN prills. An advanced data processing workflow was developed so that the segmentation and quantification of the CT data could be performed on the entire 3D volume, yet allowing the measurements (e.g.; volume, area, shape factor…) to be extracted for each individual phase (prill, open porosity, closed porosity) of each individual prill, in order to obtain statistically relevant data. Clear morphological and structural differences were seen and quantified between fertiliser and explosive products. Overall, CT can provide a very wide range of parameters that are not accessible to other techniques, destructive or non-destructive, and thus offers new insights and complementary information. T2 - 10th Conference on Industrial Computed Tomography (iCT 2020) CY - Wels, Austria DA - 04.02.2020 KW - Ammonium nitrate KW - Prill KW - Non-destructive characterisation KW - Porosity KW - Specific surface area PY - 2020 UR - http://www.ndt.net/?id=25118 SN - 1435-4934 VL - 25 IS - 2 SP - 1 EP - 6 PB - NDT.net CY - Kirchwald AN - OPUS4-50348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Diffraction-based experimental determination of Residual Stress in AM parts: A critical discussion N2 - Additive manufacturing (AM) technologies have experienced an exceedingly rapid growth, not always paralleled by the knowledge about the materials properties and performance. In particular, residual stress (RS) has been soon recognized as an issue in AM parts, so that parts are always post-heat-treated. Moreover, much effort has been spent on simulating RS, especially using finite element methods. The experimental determination of RS has thereby become increasingly important, and even simple data constitute (to date) a piece of knowledge to fill the above-mentioned gap. In particular, diffraction methods, which are basically non-destructive, offer enormous possibilities to gain knowledge on real components, since neutrons and synchrotron radiation can penetrate even heavy metals up to several millimeters (or even centimeters). Indeed, some success has been obtained, and the knowledge about the origins of the RS fields, as well as their variation as a consequence of heat or mechanical treatments, has been greatly expanded. In this talk, a few success stories will be outlined. It will be shown how the determination of RS in metallic parts (with focus on those produced by laser powder bed fusion) has even allowed showing that process parameters that were considered unimportant play a major role in the onset of stress. However, while RS is starting to be considered in the part design, deposition strategy (e.g. build plate temperature), and even in the definition of the relevant metric to assess the quality of a part, much is still to be investigated about the hypotheses underlying its experimental determination. Therefore, some aspects to be aware of, or even to date unclear will also be discussed, such as the determination of the reference unstrained samples and of the principal axes of stress. All these aspects will draw the path towards a comprehensive understanding of the process-structure-performance relationships in AM materials and parts. T2 - MSTAM 2019 CY - Bremen, Germany DA - 10.12.2019 KW - Elastic Constants KW - Residual Stress KW - Additive Manufacturing KW - Neutron Diffraction PY - 2019 AN - OPUS4-50020 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas A1 - Müller, Bernd R. A1 - Hentschel, M. P. A1 - Lange, A. A1 - Trappe, Volker A1 - Laquai, René A1 - Shashev, Yury A1 - Evsevleev, Sergei A1 - Bruno, Giovanni T1 - Progress survey of X-Ray refraction imaging techniques N2 - The most substantial innovations in radiographic imaging techniques of the last two decades aim at enhanced image contrast of weakly absorbing micro and nano structures by taking advantage of X-ray refraction effects occurring at outer and inner surfaces. The applications range from fibre reinforced plastics to biological tissues. These techniques comprise, among others, X-ray refraction topography, diffraction enhanced imaging, phase contrast imaging, Talbot-Lau grating interferometry, and refraction enhanced imaging. They all make use of selective beam deflections up to a few minutes of arc: the X-ray refraction effect. In contrast to diffraction, this type of interaction has a 100 % scattering cross section, as shown experimentally. Since X-ray refraction is very sensitive to the orientation of interfaces, it is additionally a tool to detect, e.g., fibre or pore orientation. If the detector resolution exceeds the size of (small) individual features, one detects the integral information (of inner surfaces) within the gauge volume. We describe the above-mentioned techniques, and show their experimental implementation in the lab and at a synchrotron source. We also show strategies for data processing and quantitative analysis. T2 - 19th World Conference on Non-Destructive Testing CY - Munich, Germany DA - 13.06.2016 KW - grating KW - topography KW - refraction KW - X-ray PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-366194 SN - 978-3-940283-78-8 VL - 2016/158 SP - We.3.B.2, 1 EP - 9 AN - OPUS4-36619 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Laquai, René A1 - Schaupp, Thomas A1 - Müller, Bernd R. A1 - Griesche, Axel A1 - Kupsch, Andreas A1 - Lange, Axel A1 - Kannengießer, Thomas A1 - Bruno, Giovanni T1 - 3D Crack analysis in hydrogen charged lean duplex stainless steel with synchrotron refraction CT N2 - Hydrogen in metals can cause a degradation of the mechanical properties, the so-called hydrogen embrittlement. In combination with internal stresses, hydrogen assisted cracking (HAC) can occur. This phenomenon is not completely understood yet. To better characterise the cracking behaviour, it is important to gain information about the evolution of the 3D crack network. For this purpose samples of lean duplex stainless steel were loaded with hydrogen by means of electrochemical charging and investigated by means of synchrotron refraction CT and SEM fractography after uniaxial tensile loading. Synchrotron refraction CT is an analyser-based imaging (ABI) technique. It uses a Si (111) single crystal as analyser, which is placed into the beam path between sample and detector. According to Bragg’s law only incident x-rays within a narrow range around the Bragg-angle are diffracted from the analyser into the detector. Hence, the analyser acts as an angular filter for the transmitted beam. This filtering allows to turn the refraction and scattering of x-rays into image contrast. Refraction occurs at all interfaces, where the density of the material changes and is more sensitive to density changes than the attenuation. Therefore, it is possible to detect smaller cracks than with classical x-ray imaging techniques, like CT, with comparable spacial resolution. It also visualises the 3D structure of the cracks and gains quantitative information about their morphology and distribution. Since cracks introduced by HAC are usually very small and have a small opening displacement, synchrotron refraction CT is expected to be well suited for imaging this cracking mechanism and can be a valuable tool to characterise the formation and the evolution of a 3D crack network. T2 - WCNDT 2016 CY - München, Germany DA - 13.06.2016 KW - X-ray refraction KW - Computed tomography KW - Hydrogen assisted cracking KW - Duplex stainless steel PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-366481 SN - 978-3-940283-78-8 VL - BB 158 SP - Tu.4.B.3, 1 EP - 9 AN - OPUS4-36648 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cabeza, Sandra A1 - Bruno, Giovanni A1 - Mishurova, Tatiana T1 - Characterization of multiphase metal matrix composites by means of CT and neutron diffraction N2 - The present study examines the relationship between the microstructure of multiphase metal matrix composites and their damage mechanisms. The matrix AlSi12CuMgNi was combined with 15% vol. Al₂O₃ (short fibers), and with 7% vol. Al₂O₃ + 15% vol. SiC (short fibers and whiskers, respectively). The experimental approach encompasses 3D microstructure characterization by means of computed tomography of samples (a) as-cast, (b) after heat treatment, and (c) after compression tests at room temperature. The volume fraction of different phases, their distribution, their orientation, and the presence of defects and damage are studied. The influence of the addition of SiC particles on mechanical properties of composite was investigated. Phase-specific load partition analysis for samples with fiber plane parallel to load was performed by using neutron diffraction (ND) during in-situ compression. ND results show damage in the Si phase, while Al₂O₃ short fibers carry load without damage until failure. The computed tomography observations confirm the load partition analysis. T2 - WCNDT CY - München, Germany DA - 13.06.2016 KW - thermal treatment KW - synchrotron CT KW - neutron diffraction KW - composite KW - aluminum KW - residual stress PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-365499 AN - OPUS4-36549 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shashev, Yury A1 - Kupsch, Andreas A1 - Lange, Axel A1 - Britzke, Ralf A1 - Bruno, Giovanni A1 - Mueller, Bernd R. A1 - Hentschel, Manfred P. T1 - Talbot- Lau interferometry with a non- binary phase grating for non-destructive testing N2 - Grating interferometric set-ups have been established in the last decade. They are promising candidates to obtain enhanced image contrast from weakly absorbing micro and nano structures. They are based on X-ray refraction and near-field diffraction using the Talbot effect. At the expense of taking multiple images, Talbot-Lau grating interferometry allows separating the absorption, refraction, and scattering contributions by analysing the disturbances of a phase grating interference pattern. Contrary to other refraction enhanced methods, this technique can be applied using conventional X-ray tubes (divergent, polychromatic source). This makes it attractive to solve typical non-destructive testing problems. We investigated the efficiency of phase gratings, i.e. the visibility (the amplitude of oscillations) upon variation of propagation distance and phase grating rotation around an axis parallel to the grid lines. This grating rotation changes the grating shape (i.e. the distributions of phase shifts). This can yield higher visibilities than derived from rectangular shapes. Our study includes experimental results obtained from synchrotron radiation, as well as simulations for monochromatic radiation. The advantages of Talbot-Lau interferometry are demonstrated at the example of glass capillaries. T2 - WCNDT2016 CY - Munich, Germany DA - 13.06.2016 KW - Phase-contrast X-ray imaging KW - Talbot- Lau interferometry KW - Phase grating KW - Visibility KW - Synchrotron radiation PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-365987 SN - 978-3-940283-78-8 VL - BB 158 SP - Tu.3.G.2., 1 EP - 9 AN - OPUS4-36598 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shashev, Yury A1 - Kupsch, Andreas A1 - Lange, Axel A1 - Britzke, Ralf A1 - Bruno, Giovanni A1 - Müller, Bernd R. A1 - Hentschel, M. P. T1 - Talbot- Lau interferometry with a non- binary phase grating for non-destructive testing N2 - Grating interferometric set-ups have been established in the last decade. They are promising candidates to obtain enhanced image contrast from weakly absorbing micro and nano structures. They are based on X-ray refraction and near-field diffraction using the Talbot effect. At the expense of taking multiple images, Talbot-Lau grating interferometry allows separating the absorption, refraction, and scattering contributions by analysing the disturbances of a phase grating interference pattern. Contrary to other refraction enhanced methods, this technique can be applied using conventional X-ray tubes (divergent, polychromatic source). This makes it attractive to solve typical non-destructive testing problems. We investigated the efficiency of phase gratings, i.e. the visibility (the amplitude of oscillations) upon variation of propagation distance and phase grating rotation around an axis parallel to the grid lines. This grating rotation changes the grating shape (i.e. the distributions of phase shifts). This can yield higher visibilities than derived from rectangular shapes. Our study includes experimental results obtained from synchrotron radiation, as well as simulations for monochromatic radiation. The advantages of Talbot-Lau interferometry are demonstrated at the example of glass capillaries. T2 - 19th World Conference on Non-Destructive Testing 2016 CY - Munich, Germany DA - 13.06.2016 KW - Talbot- Lau interferometry KW - Phase grating KW - Non-destructive testing PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-383163 SP - Tu_3_G_2, 1 EP - 9 AN - OPUS4-38316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thiede, Tobias A1 - Mishurova, Tatiana A1 - Evsevleev, Sergei A1 - Serrano-Munoz, Itziar A1 - Gollwitzer, Christian A1 - Bruno, Giovanni T1 - 3D shape analysis of powder for laser beam melting by synchrotron X-ray CT N2 - The quality of components made by laser beam melting (LBM) additive manufacturing is naturally influenced by the quality of the powder bed. A packing density <1 and porosity inside the powder particles lead to intrinsic voids in the powder bed. Since the packing density is determined by the particle size and shape distribution, the determination of these properties is of significant interest to assess the printing process. In this work, the size and shape distribution, the amount of the particle’s intrinsic porosity, as well as the packing density of micrometric powder used for LBM, have been investigated by means of synchrotron X-ray computed tomography (CT). Two different powder batches were investigated: Ti–6Al–4V produced by plasma atomization and stainless steel 316L produced by gas atomization. Plasma atomization particles were observed to be more spherical in terms of the mean anisotropy compared to particles produced by gas atomization. The two kinds of particles were comparable in size according to the equivalent diameter. The packing density was lower (i.e., the powder bed contained more voids in between particles) for the Ti–6Al–4V particles. The comparison of the tomographic results with laser diffraction, as another particle size measurement technique, proved to be in agreement. KW - Additive manufacturing KW - Laser beam melting KW - Synchrotron computed tomography KW - Powder analysis KW - Imaging PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-474070 DO - https://doi.org/10.3390/qubs3010003 SN - 2412-382X VL - 3 IS - 1 SP - 3, 1 EP - 12 PB - MDPI AN - OPUS4-47407 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Khrapov, D. A1 - Surmeneva, M. A1 - Koptioug, A. A1 - Evsevleev, Sergei A1 - Léonard, Fabien A1 - Bruno, Giovanni A1 - Surmenev, R. T1 - X-ray computed tomography of multiple-layered scaffolds with controlled gradient cell lattice structures fabricated via additive manufacturing N2 - In this paper we report on the characterization by X-ray computed tomography of calcium phosphate (CaP) and polycaprolactone (PCL) coatings on Ti-6Al-4V alloy scaffolds used as a material for medical implants. The cylindrical scaffold has greater porosity of the inner part than the external part, thus, mimicking trabecular and cortical bone, respectively. The prismatic scaffolds have uniform porosity. Surface of the scaffolds was modified with calcium phosphate (CaP) and polycaprolactone (PCL) by dip-coating to improve biocompatibility and mechanical properties. Computed tomography performed with X-ray and synchrotron radiation revealed the defects of structure and morphology of CaP and PCL coatings showing small platelet-like and spider-web-like structures, respectively. KW - Additive manufacturing KW - Lattice structure KW - Multiple-layered scaffold KW - Coating KW - Medical implants KW - Computed tomography KW - Polycaprolactone KW - Calcium phosphate PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-471931 UR - http://stacks.iop.org/1742-6596/1145/i=1/a=012044 DO - https://doi.org/10.1088/1742-6596/1145/1/012044 SN - 1742-6596 VL - 1145 SP - 012044, 1 EP - 7 PB - IOP AN - OPUS4-47193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Procedures to Quantitatively Characterize Morphological Features of Triply Periodic Minimal Surface Structures N2 - Additively manufactured (AM) metallic sheet-based Triply Periodic Minimal Surface Structures (TPMSS) meet several requirements in both bio-medical and engineering fields: Tunable mechanical properties, low sensitivity to manufacturing defects, mechanical stability, and high energy absorption. However, they also present some challenges related to quality control. In fact, the optimization of both the AM process and the properties of TPMSS is impossible without considering structural characteristics as manufacturing accuracy, internal defects, and as well as surface topography and roughness. In this study, the quantitative non-destructive analysis of TPMSS manufactured from Ti-6Al-4V alloy by electron beam melting was performed by means of laboratory X-ray computed tomography (XCT). T2 - International conference on tomography of material and structures 2022 CY - Grenoble, France DA - 27.06.2022 KW - Additive manufacturing KW - Scaffold KW - Lightweight structures KW - Computed tomography PY - 2022 AN - OPUS4-55229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Avoid living dangerously: non-destructive characterization of AM parts from powder to end-of-life N2 - The freeform and the revolutionary design possibilities offered by additive manufacturing have skyrocketed the amount of optimization studies in the realm of engineering, and metallic additive manufactured parts are becoming a reality in industry. Not surprisingly, this has not been paralleled by a similar enthusiastic wave in the realm of materials science, and still very little is known about AM materials properties. This has the consequence that, typically, conventional materials properties are still used in design and even in simulations. lt is necessary to dig a lot deeper than at present, in order to understand these new materials classes, and in particular their microstructure and their intemal stresses, largely different from their cast or wrought companions. T2 - ISAM Konferenz 2019 CY - Dresden, Germany DA - 29.01.2019 KW - Computed Tomography KW - Microstructure KW - Metals KW - Additive Manufacturing PY - 2019 AN - OPUS4-47331 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Léonard, Fabien A1 - Zhang, Zhen A1 - Malow, Marcus A1 - Bruno, Giovanni T1 - 3D characterisation of ammonium nitrate powders by X-ray computed tomography N2 - The mixture of ammonium nitrate (AN) prills and fuel oil (FO), usually called ANFO, is extensively used in the mining industry as a bulk industrial explosive. One of the major performance predictors of ANFO mixtures is the fuel oil retention, which is itself governed by the porosity of the AN prills. Standardised tests routinely used to assess oil retention face several important limitations; the first being the difficulty to cover the wide range of porosity contents and morphologies from different types of ammonium nitrate prills; the second being the inability to evaluate the closed porosity, which is an important factor regarding the sensitivity of the explosive to detonation. In this study, we present how X-ray computed tomography (XCT), and the associated advanced data processing workflow, can be used to fully characterise the structure and morphology of AN prills. We show that structural parameters such as volume fraction of the different phases and morphological parameters such as specific surface area and shape factor can be reliably extracted from the XCT data, and that there is a good agreement with the measured oil retention values. XCT can therefore be employed to non-destructively and accurately evaluate and characterise porosity in ammonium nitrate prills. T2 - 23rd Seminar on New Trends in Research of Energetic Materials CY - Meeting was canceled DA - 01.04.2020 KW - Ammonium nitrate KW - Prill KW - Non-destructive characterisation KW - Porosity KW - Specific surface area PY - 2020 SP - 163 EP - 171 AN - OPUS4-51272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - 2D and 3D imaging chracterization techniques for porous ceramics N2 - The combination of microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on porous material properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of porosity in ceramics. Moreover, I will show how not-so-novel 2D characterization techniques, based X-ray refraction, can allow a great deal of insights in the damage evolution in microcracked (and porous) ceramics. I will show how X-ray refraction can detect objects (e.g. microcracks) below its own spatial resolution. Finally, I will discuss the link between the microstructural findings and the mechanical properties of porous microcracked ceramics. T2 - CIMTEC 2018 CY - Perugia, Italy DA - 04.06.2018 KW - Orientation KW - Cordierite KW - Beta-eucrytite KW - Porosity KW - Microcracking KW - Computed tomography KW - X-ray refraction PY - 2018 AN - OPUS4-45119 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishurova, Tatiana A1 - Artzt, Katia A1 - Haubrich, Jan A1 - Bruno, Giovanni A1 - Requena, Guillermo T1 - An assessment of subsurface residual stress in Selective Laser Melted Ti-6Al-4V parts N2 - In the present study, Ti-6Al-4V bridge-like specimens were manufactured additively by selective laser melting (SLM) under different laser scanning speed conditions in order to compare the effect of process energy density on the residual stress state. Subsurface residual stress analysis was conducted by means of synchrotron diffraction in energy dispersive mode for three conditions: as-built on base plate, released from base plate, and after heat treatment on the base plate. The quantitative residual stress characterization shows a correlation with the qualitative bridge curvature method. Computed tomography (CT) was carried out to ensure that no stress relief took place owing to the presence of porosity. CT allows obtaining spatial and size pores distribution which helps in optimization of the SLM process. High tensile residual stresses were found at the lateral surface for samples in the as-built conditions. We observed that higher laser energy density during fabrication leads to lower residual stresses. Samples in released condition showed redistribution of the stresses due to distortion. A method for the calculation of the stress associated to distortion of the parts after cutting from base plate is proposed. The distortion measurements were used as input for FEM simulations. T2 - Symposium Zerstörungsfreie Materialcharakterisierung. Charakterisierung additiv gefertigter Komponenten CY - Berlin, Germany DA - 28.11.2017 KW - Additive manufacturing KW - Selective laser melting KW - Residual stress KW - Synchrotron X-ray diffraction PY - 2017 AN - OPUS4-43214 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fernández, R. A1 - Bokuchava, G. A1 - Toda-Caraballo, I. A1 - Bruno, Giovanni A1 - Turchenko, V. A1 - Gorshkova, Y. A1 - González-Doncel, G. T1 - Analysis of the Combined Strengthening Effect of Solute Atoms and Precipitates on Creep of Aluminum Alloys N2 - The creep strengthening mechanisms in (age-hardenable) aluminum alloys are analyzed on the basis of a new microstructural study of powder samples, an analysis of a comprehensive revision of creep data from the literature, and a new modeling approach. A strategy based on the strength difference (SD) method to separate the contributions of solid solution atoms and precipitates to creep strengthening is proposed. The new methodology considers the combination of the two contributions avoiding the need of a threshold stress term in the creep equation. The contribution of both precipitates and solid solution is taken into account by means of the analysis of the lattice parameter variation with aging time. For this study, powders of two commercial AA2xxx alloys have been analyzed using diffraction methods. The experimental results are modeled using Lubarda’s approach combined with the SD method. KW - Composites KW - Aluminum alloys KW - Creep models KW - Neutron Diffraction KW - Stress exponent PY - 2020 DO - https://doi.org/10.1002/adem.201901355 VL - 22 IS - 4 SP - 1901355 PB - WILEY-VCH Verlag AN - OPUS4-51055 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni A1 - Mishurova, Tatiana A1 - Serrano-Munoz, Itziar A1 - Ulbricht, Alexander A1 - Fritsch, Tobias A1 - Sprengel, Maximilian A1 - Evans, Alexander A1 - Kromm, Arne A1 - Madia, Mauro ED - Bruno, Giovanni T1 - A Critical Discussion on the Diffraction-Based Experimental Determination of Residual Stress in AM Parts N2 - As opposed to reviewing results on experimental determination of residual stress by diffraction, this paper discusses the open issues when dealing with residual stress determination in additive manufactured parts, in particular those manufactured with laser powder bed fusion techniques. Three points are addressed in detail: (a) the proper determination of the strain-free reference d0, (b) the problem of the determination of the principal axes, and (c) the use of the correct diffraction elastic constants. It is shown that all methods to determine the strain-free reference d0 suffer from caveats, and care must be taken in evaluating the most suitable for the problem being tackled. In addition, it is shown that, in some systems, the principal axes do correspond to the geometrical axes of the specimen, but this needs to be systematically checked, especially in the case of uni- or bidirectional hatching strategies. Finally, the need to experimentally determine the proper diffraction elastic constants is underlined, especially in the case of strongly textured specimens, which again depends on the deposition strategy. T2 - ASTM ICAM 2020 – ASTM International Conference on Additive Manufacturing CY - Online meeting DA - 16.11.2020 KW - Additive Manufacturing KW - Diffraction KW - Residual Stress PY - 2020 DO - https://doi.org/10.1520/STP163120190148 VL - STP1631 SP - 122 EP - 138 PB - ASTM International CY - USA AN - OPUS4-51347 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Micromechanics of internal stresses in multiphase materials Part I- Residual Stress analysis by Diffraction N2 - In this Seminar cycle I will present first diffraction methods to determine residual stress and investigate micromechanical properties of complex materials, and then particularize the treatment with applications to porous microcracked ceramics for diesel particulate filter applications. I will show that neutron diffraction is particularly suited for bulk studies, where 3D stresses are needed. The advantages to use Time-of-Flight or steady state sources will be discussed, together with the problematic of the determination of absolute RS values. Finally, the behavior of DPF materials under applied load or at high temperatures will be discussed under the combination of macroscopic and microscopic tests. T2 - ATHOR webinar "Micromechanics of internal stresses in multiphase materials" CY - Online meeting DA - 12.01.2021 KW - Porosity KW - Neutron Diffraction KW - Residual Stress KW - Non-linear stress-strain KW - Anisotropy KW - Microcracking KW - Imaging PY - 2021 AN - OPUS4-52125 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Micromechanics of internal stresses in multiphase materials, Part II- Mechanical properties of microcracked and porous materials N2 - In this Seminar cycle I will present first diffraction methods to determine residual stress and investigate micromechanical properties of complex materials, and then particularize the treatment with applications to porous microcracked ceramics for diesel particulate filter applications. I will show that neutron diffraction is particularly suited for bulk studies, where 3D stresses are needed. The advantages to use Time-of-Flight or steady state sources will be discussed, together with the problematic of the determination of absolute RS values. Finally, the behavior of DPF materials under applied load or at high temperatures will be discussed under the combination of macroscopic and microscopic tests. T2 - ATHOR webinar "Micromechanics of internal stresses in multiphase materials" CY - Online meeting DA - 26.01.2021 KW - Porosity KW - Neutron Diffraction KW - Residual Stress KW - Non-linear stress-strain KW - Anisotropy KW - Microcracking KW - Imaging PY - 2021 AN - OPUS4-52126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni T1 - Assessing the safety of new technologies: Summary of Project AGIL N2 - In Additive Manufacturing everybody is talking about Free Form, Unconventional Design, Re-thinking Components, “Think out of the box”. However, there are a few outstanding question: a) What are the material properties ? They certainly differ from literature values for conventional materials; b) How about the microstructure? It is different from conventional materials. Does it stay so with ageing? How does it form? c) Do we properly take residual stress into account? We often blame them for our ignorance about failure scenarios. d) Do we apply tailored heat treatments? Very often, we follow conventional schedules… This talk describes the summary of the efforts carried out within the BAM Project AGIL. At BAM, we aimed to thoroughly investigate the microstructure and how it evolves as a function of load and temperature (service), to determine the material properties after different process and service conditions, to properly determine residual stress and the way it impacts mechanical properties and component performance, to properly quantify the impact of (unavoidable?) defects, and to determine heat treatments tailored to the process-specific material (stress relieve, microstructure homogenization etc.). The Project AGIL was and is intimately coupled with the project ProMoAM, dealing with online monitoring of AM processes. T2 - Workshop In-situ Monitoring and Microstructure Development in Additive Manufactured Alloys CY - Online meeting DA - 19.04.2021 KW - Mechanical properties KW - Additive manufacturing KW - Residual Stress KW - Microstructure KW - Fatigue KW - Creep PY - 2021 AN - OPUS4-52581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishurova, Tatiana A1 - Evsevleev, Sergei A1 - Artzt, K. A1 - Haubrich, J. A1 - Sevostianov, I. A1 - Requena, G. A1 - Bruno, Giovanni T1 - Micromechanical behavior of annealed Ti-6Al-4V produced by Laser Powder Bed Fusion N2 - The micromechanical behavior of an annealed Ti-6Al-4V material produced by Laser Powder Bed Fusion was characterized by means of in-situ synchrotron X-ray diffraction during a tensile test. The lattice strain evolution was obtained parallel and transversal to the loading direction. The elastic constants were determined and compared with the conventionally manufactured alloy. In the plastic regime, a lower plastic anisotropy exhibited by the lattice planes was observed along the load axis (parallel to the building direction) than in the transverse direction. Also, the load transfer from α to β phase was observed, increasing global ductility of the material. The material seems to accumulate a significant amount of intergranular strain in the transverse direction. KW - Additive manufacturing KW - Ti-6Al-4V KW - Anisotropy KW - Intergranular strain KW - Synchrotron X-ray diffraction PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547406 DO - https://doi.org/10.1080/26889277.2022.2063763 VL - 2 IS - 1 SP - 186 EP - 201 PB - Taylor & Francis AN - OPUS4-54740 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fardan, Ahmed A1 - Fazi, Andrea A1 - Schröder, Jakob A1 - Mishurova, Tatiana A1 - Deckers, Tobias A1 - Bruno, Giovanni A1 - Thuvander, Matthias A1 - Markström, Andreas A1 - Brodin, Hakan A1 - Hryha, Eduard T1 - Microstructure tailoring for crack mitigation in CM247LC manufactured by powder bed fusion – Laser beam N2 - Tailored microstructures in powder bed fusion – laser beam (PBF-LB) can aid in crack mitigation of non-weldable Ni-base superalloys such as CM247LC. This study explores the effect of a range of stripe widths from 5 mm down to 0.2 mm to control solidification cracking, microstructure, and residual stress in CM247LC manufactured by PBF-LB. The decrease in melt pool depth with the reduction in stripe width from 5 to 0.2 mm promoted the < 100 > crystallographic texture along the build direction. The crack density measurements indicated that there is an increase from 0.62 mm/mm2 (5 mm) to 1.71 mm/mm2 (1 mm) followed by a decrease to 0.33 mm/mm2 (0.2 mm). Atom probe tomography investigations at high-angle grain boundaries revealed that there is higher Hf segregation in 0.2 mm stripe width when compared to 5 mm. This indicates that the cracking behavior is likely influenced by the grain boundary segregation which in turn is dependent on melt pool shape/size and mushy zone length indicated by accompanying simulations. Residual stress, measured by X-ray diffraction, decreased from 842 MPa (5 mm) to 690 MPa (1 mm), followed by an abnormal rise to 842 MPa (0.7 mm) and 875 MPa (0.5 mm). This residual stress behavior is likely associated with the cracks acting as a stress relief mechanism. However, the 0.2 mm stripe width exhibited the lowest stress of 647 MPa, suggesting a different mechanism for stress relief, possibly due to re-melting. These findings highlight the critical role of stripe width as a scan strategy in PBF-LB processing of crack-susceptible alloys. KW - Additive manufacturing KW - Residual stress KW - Scanning strategy KW - Non-weldable superalloy KW - Solidification cracking PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624606 DO - https://doi.org/10.1016/j.addma.2025.104672 SN - 2214-7810 VL - 99 SP - 1 EP - 14 PB - Elsevier B.V. AN - OPUS4-62460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -