TY - JOUR A1 - Preß, Henning A1 - Seifert, B. A1 - Wagner, H. M. T1 - Vergleich von Meßverfahren zur Bestimmung von Ozon JF - Gesundheits-Ingenieur PY - 1976 SN - 0932-6200 SN - 0016-9277 SN - 0720-9312 VL - 97 IS - 9 SP - 225 EP - 228 PB - Oldenbourg CY - München AN - OPUS4-8577 LA - deu 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 - Lugovtsova, Yevgeniya A1 - Zeipert, H. A1 - Johannesmann, S. A1 - Nicolai, Marcel A1 - Prager, Jens A1 - Henning, B. T1 - К определению прочности клеевого соединения в многослойных материалах путем исследования областей расталкивания бегущих упругих волн T1 - Towards the determination of adhesive bonding strength of multi-layered materials by investigating guided wave mode repulsion T2 - Сборник тезисов XXX Всероссийской школы-конференции МАТЕМАТИЧЕСКОЕ МОДЕЛИРОВАНИЕ В ЕСТЕСТВЕННЫХ НАУКАХ N2 - Бегущие упругие волны часто используются в области неразрушающего контроля для определения механических характеристик материалов. Поскольку склеивание различных материалов является широко используемым методом в автомобильной и авиационной промышленности, необходима надежная система измерения для определения качества таких клеевых соединений. Дисперсионные кривые для многослойных волноводов при наличии клеевых прослоек характеризуются появлением эффекта расталкивания нормальных мод в тех областях, где соответствующие моды для отдельных материалов пересекались бы. Таким образом, в зависимости от качества клеевого соединения расстояние между этими модами изменяется. Используя комбинацию экспериментальных и численных данных, в настоящей работе представлен подход к определению параметра, указывающего на качество клеевого соединения. T2 - XXX Всероссийская школа-конференция МАТЕМАТИЧЕСКОЕ МОДЕЛИРОВАНИЕ В ЕСТЕСТВЕННЫХ НАУКАХ CY - Online meeting DA - 06.10.2021 KW - многослойный волновод KW - волны лэмбовского типа KW - контроль качества клеевого соединения PY - 2021 SP - 1 EP - 3 AN - OPUS4-53769 LA - rus AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zeipert, H. A1 - Johannesmann, S. A1 - Nicolai, Marcel A1 - Lugovtsova, Yevgeniya A1 - Prager, Jens A1 - Henning, B. T1 - Quantifying the coupling strength of adhesively bonded materials by investigating mode repulsion regions T2 - Tagungsband DAGA 2021 - 47. Jahrestagung für Akustik N2 - In the field of non-destructive testing, Lamb waves are often used for material characterisation. The increasing computational capabilities further enable complex and detailed simulations to predict the material behaviour in reality. Since adhesive bonding of different materials is a widely used method in modern applications, a reliable measurement system to determine the quality of these adhesive bonds is needed. Investigations of the dispersive behaviour of acoustic waves in adhesively bonded multi-layered waveguides show mode repulsions in the dispersion diagrams in regions where the modes of the single materials would otherwise intersect. In previous works, changes of the distance between those modes with respect to the bonding quality are observed. The experimental data for this investigation is generated using pulsed laser radiation to excite broadband acoustic waves in plate like specimens which are detected by a piezoelectric ultrasonic transducer. Numerical data is generated using simulations via a semi-analytical finite element method. Using a combination of experimental and numerical data, the present work introduces an approach to determine a parameter which indicates the bonding quality in relation to an ideal material coupling. T2 - DAGA 2021 CY - Vienna, Austria DA - 15.08.2021 KW - Ultrasonic guided waves KW - Multi-layered structures KW - Laser excited ultrasonic waves PY - 2021 SP - 1532 EP - 1535 AN - OPUS4-53581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ziesche, R. F. A1 - Robinson, J. B. A1 - Markötter, Henning A1 - Bradbury, R. A1 - Tengattini, A. A1 - Lenoir, N. A1 - Helfen, L. A1 - Kockelmann, W. A1 - Kardjilov, N. A1 - Manke, I. A1 - Brett, D. J. L. A1 - Shearing, P. R. T1 - Editors’ Choice—4D Neutron and X-ray Tomography Studies of High Energy Density Primary Batteries: Part II. Multi-Modal Microscopy of LiSOCl2 Cells JF - Journal of the Electrochemical Society N2 - The ability to track electrode degradation, both spatially and temporally, is fundamental to understand performance loss during operation of lithium batteries. X-ray computed tomography can be used to follow structural and morphological changes in electrodes; however, the direct detection of electrochemical processes related to metallic lithium is difficult due to the low sensitivity to the element. In this work, 4-dimensional neutron computed tomography, which shows high contrast for lithium, is used to directly quantify the lithium diffusion process in spirally wound Li/SOCl2 primary cells. The neutron dataset enables the quantification of the lithium transport from the anode and the accumulation inside the SOCl2 cathode to be locally resolved. Complementarity between the collected neutron and X-ray computed tomographies is shown and by applying both methods in concert we have observed lithium diffusion blocking by the LiCl protection layer and identified all cell components which are difficult to distinguish using one of the methods alone. KW - Lithium-ion battery KW - Room-temperature KW - Thermal runaway KW - Gas evolution KW - Cells PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520890 DO - https://doi.org/10.1149/1945-7111/abbfd9 VL - 167 SP - 140509 PB - IOP Science AN - OPUS4-52089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zeipert, H. A1 - Claes, L. A1 - Johannesmann, S. A1 - Webersen, M. A1 - Lugovtsova, Yevgeniya A1 - Prager, Jens A1 - Henning, B. T1 - Measurement and simulation of Lamb waves in adhesive-bonded multilayer systems T2 - SMSI 2021 - Measurement Science N2 - Lamb waves are a common tool in the field of non-destructive testing and are widely used for materialcharacterisation. Further, the increasing computational capability of modern systems enables the Simulation of complex and detailed material models. This work demonstrates the possibility of simulating an adhesive-bonded multilayer system by characterising each layer individually, and introduces an Approach for determining the dispersive behaviour of acoustic waves in a multilayer system via real measurements. T2 - SMSI 2021 Conference – Sensor and Measurement Science International CY - Online meeting DA - 03.05.2021 KW - Adhesive bonds KW - Lamb waves KW - Elastic constants KW - Non-Destructive Testing KW - Ultrasound PY - 2021 DO - https://doi.org/10.5162/SMSI2021/A8.2 SP - 91 EP - 92 AN - OPUS4-52634 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, Ricky A1 - Sturm, Patrick A1 - Geddes, D.A. A1 - Keßler, S. A1 - Walkley, B. A1 - Gluth, Gregor T1 - The influence of curing temperature on the strength and phase assemblage of hybrid cements based on GGBFS/FA blends JF - Frontiers in Materials N2 - Hybrid cements are composites made of Portland cement or Portland clinker and one or more supplementary cementitious materials like slag, fly ash or metakaolin, activated with an alkali salt. To date, their hydration mechanism and the phase formation at various temperatures is insufficiently understood, partly due to the large variability of the raw materials used. In the present study, three hybrid cements based on ground granulated blast furnace slag, fly ash, Portland clinker and sodium sulfate, and an alkali-activated slag/fly ash blend were cured at 10 and 21.5°C, and subsequently analyzed by XRD, 27Al MAS NMR, and TGA. The compressive strength of the hybrid cements was higher by up to 27% after 91-day curing at 10°C, compared to curing at 21.5°C. The experimental results as well as thermodynamic modeling indicate that the differences in compressive strength were related to a different phase assemblage, mainly differing amounts of strätlingite and C-N-A-S-H, and the associated differences of the volume of hydration products. While the strätlingite was amorphous to X-rays, it could be identified by 27Al MAS NMR spectroscopy, TGA and thermodynamic modeling. The microstructural properties of the hybrid cements and the alkali-activated slag/fly ash blend as well as the compatibility between thermodynamic modeling results and experimental data as a function of curing temperature and time are discussed. KW - Hybrid cements KW - Strätlingite KW - Thermodynamic modelling KW - Hydration PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557767 DO - https://doi.org/10.3389/fmats.2022.982568 SN - 2296-8016 VL - 9 SP - 1 EP - 16 PB - Frontiers AN - OPUS4-55776 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gravenkamp, Hauke A1 - Bause, F. A1 - Rautenberg, J. A1 - Henning, B. ED - Declercq, N. F. T1 - Model Based Sensitivity Analysis in the Determination of Viscoelastic Material Properties Using Transmission Measurements through Circular Waveguides T2 - Physics Procedia N2 - Several ultrasonic approaches for material determination are formulated in terms of an (nonlinear) inverse problem, e.g. immersion technique (Castaings et al. (2000)) or plate-waveguide techniques (Marzani et al. (2012)). In this contribution we focus on cylindrical waveguides for ultrasonic material determination and especially on the sensitivity of recorded transmission signals to the material properties. We utilize composite scaled sensitivities to determine the information content that can be achieved by the setup to certain parameters and discuss the limitations of the approach. T2 - ICU International Congress on Ultrasonics 2015 CY - Georgia Tech Lorraine, Metz, France DA - 10.05.2015 KW - Ultrasonic material determination KW - Sensitivity KW - Inverse problem PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-372551 DO - https://doi.org/10.1016/j.phpro.2015.08.127 SN - 1875-3892 VL - 70 SP - 204 EP - 207 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-37255 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bause, F. A1 - Schröder, A. A1 - Rautenberg, J. A1 - Henning, B. A1 - Gravenkamp, Hauke T1 - Time-causal material modeling in the simulation of guided waves in circular viscoelastic waveguides T2 - IUS 2014 - IEEE International ultrasonics symposium (Proceedings) N2 - For the description of linear viscoelasticity, the fractional Zener model may be used. Based on the spectral decomposition of the elasticity matrix as proposed by Theocaris, we generalize the one-dimensional analysis of the material model into three dimensions and discuss appropriate simplifications to reduce the amount of unknowns for the material description. Then, a decomposition approach that considers the real valued frequency dependence of the viscoelastic moduli and the real valued frequency dependence of their attenuation separately is proposed. The Scaled Boundary Finite Element Method is used for the efficient computation of the phase velocity dispersion and the modal wave fields given a frequency dependent but real valued viscoelasticity matrix. Utilizing the modal expansion approach, the transmitting and receiving transducer are taken into account to compute the modal amplitudes. Combining these modal amplitudes, the phase velocity dispersion and re-introducing the viscoelastic attenuation results in a transfer function of the viscoelastic waveguide including excitation and receiving conditions. The performance of the proposed simulation model is shown by comparison to measurements taken on a polypropylene sample. T2 - IUS 2014 - IEEE International ultrasonics symposium CY - Chicago, IL, USA DA - 03.09.2014 PY - 2014 SN - 978-1-4799-7049-0 DO - https://doi.org/10.1109/ULTSYM.2014.0333 SP - 1348 EP - 1351 AN - OPUS4-31869 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinrich, Thomas A1 - Traulsen, Christoph Hans-Henning A1 - Darlatt, Erik A1 - Richter, S. A1 - Poppenberg, J. A1 - Traulsen, N.L. A1 - Linder, I. A1 - Lippitz, Andreas A1 - Dietrich, Paul A1 - Dib, B. A1 - Unger, Wolfgang A1 - Schalley, C.A. T1 - The versatility of 'Click' reactions at surfaces: Molecular recognition at interfaces JF - RSC Advances N2 - In order to investigate molecular recognition on surfaces, an azide-functionalized monolayer was deposited on gold. The monolayer was characterized by X-ray photoelectron spectroscopy (XPS) and angle-resolved near-edge X-ray absorption fine structure (NEXAFS) experiments and the decomposition of the azide upon irradiation with X-ray beams was investigated. Subsequently, various alkyne-functionalized host and guest molecules were attached to the azide by 1,3-dipolar cycloaddition. These modified surfaces and their host–guest chemistry were analysed by XPS and angle-resolved NEXAFS. The reversibility of guest binding was shown for one example as a proof of principle. KW - 'Click' reaction KW - Azide-terminated surfaces KW - SAMs KW - Host guest molecules KW - Molecular recognition at interfaces PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-306463 DO - https://doi.org/10.1039/C4RA01730G SN - 2046-2069 VL - 4 IS - 34 SP - 17694 EP - 17702 PB - RSC Publishing CY - London AN - OPUS4-30646 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -