TY - JOUR
A1 - Yang, Chunliang
A1 - Yang, Fan
A1 - Meng, Xiangmeng
A1 - Putra, Stephen Nugraha
A1 - Bachmann, Marcel
A1 - Rethmeier, Michael
T1 - Phase-field simulation of the dendrite fragmentation by electromagnetic stirring in AA5754 aluminum alloy laser beam welding
N2 - A phase-field model including magnetic field induced dendrite fragmentation was established and applied to the cases with different initial crystal nuclear positions for AA5754 aluminum alloy electromagnetic laser beam welding. Compare the calculated results that include dendrite fragmentation caused by the thermal electromagnetic Lorentz force with the results that consider only the thermal electromagnetic Lorentz force, without fragmentation, at the characteristic time instants. Both in the early and late stages, the small fragmentation at the dendrite tip promotes the number of higher-order branches and their growth, especially in the direction perpendicular to the solidification. The later stage fragmentation has the possibility of breaking one grain into several, which verifies the possibility of grain refinement caused by dendrite fragmentation. The fracture surface caused by fragmentation also makes more solid-liquid interfaces and their growth. In addition, the cases with different initial nuclear positions were compared. The grain growth in the low-temperature zone can be inhibited by the equiaxed grains' fragmentation at the high-temperature area (179.8 μm² and 14.7 % start at the center, 115.4 μm² and 9.4 % start at the high-temperature corner, 134.3 μm² and 10.9 % start at the low-temperature corner), which is another kind of grain refinement by the dendrite fragmentation. This kind of inhibition effect on grain growth in the low-temperature region will be enhanced with the increasing time interval between the two crystal nuclei’ appearance (179.8 μm² and 14.7 % when virtual grains appear at t = 4.3803 s and t = 4.3803 s, 134.3 μm² and 10.9 % at t = 4.0977 s and t = 3.9564 s, and 115.4 μm² and 9.4 % at t = 3.8151 s and t = 3.5325 s).
KW - Laser beam welding
KW - Electromagnetic
KW - Aluminum alloys
KW - Phase field method
KW - Equiaxed grain
KW - Dendrite fragmentation
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656610
DO - https://doi.org/10.1016/j.cwe.2025.100014
SN - 3117-4159
VL - 35
IS - 1
SP - 1
EP - 12
PB - Elsevier B.V.
AN - OPUS4-65661
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Meng, Xiangmeng
A1 - Bachmann, Marcel
A1 - Kising, Pascal
A1 - Yang, Fan
A1 - Rethmeier, Michael
T1 - Prediction of weld pool and keyhole geometries in high-power laser beam welding through a physics-informed generative artificial intelligence approach
N2 - The weld pool and keyhole geometries are critical characteristics in evaluating the stability of the high-power laser beam welding (LBW) process and determining the resultant weld quality. However, obtaining these data through experimental or numerical methods remains challenging due to the difficulties in experimental measurements and the high computational demands of numerical modelling. This paper presents a physics-informed generative approach for predicting weld pool and keyhole geometries in the LBW process. With the help of a well experimentally validated numerical model considering the underlying physics in the LBW, the geometries of the weld pool and keyhole under various welding conditions are calculated, serving as the dataset of the generative model. A conditional variational autoencoder model is employed to generate realistic 2D weld pool and keyhole geometries from the welding parameters. We utilize a β-variational autoencoder model with the evidence lower bound loss function and include Kullback–Leibler divergence annealing to better optimize model performance and stability during training. The generated results show a good agreement with the ground truth from the numerical simulation. The proposed approach exhibits the potential of physics-informed generative models for a rapid and accurate prediction of the weld pool geometries across a diverse range of process parameters, offering a computationally efficient alternative to full numerical simulations for process optimization and control in laser beam welding processes.
KW - Laser beam welding
KW - Generative artificial intelligence
KW - Machine learning
KW - Numerical simulation
KW - Weld pool
KW - Keyhole dynamics
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656621
DO - https://doi.org/10.2351/7.0001862
SN - 1042-346X
VL - 38
IS - 1
SP - 1
EP - 8
PB - Laser Institute of America
AN - OPUS4-65662
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scharek, Vera M.
A1 - Traub, Heike
A1 - Meermann, Björn
T1 - A direct solid sampling approach for fluorine determination via ETV/ICP-QQQ-MS
N2 - Organic fluorine sum parameters are used to detect F-containing pollutants, e.g., per- and polyfluoroalkyl substances (PFASs), in the environment, within materials, or for monitoring technical processess, e.g., thermal decomposition of PFAS during municipal waste incineration. However, established approaches determining the extractable organic and adsorbable organic fluorine content (EOC and AOC) require laborious and error-prone sample preparation. We report a solid sampling-electrothermal vaporization (ETV) method for direct fluorine measurement based on the formation of [138Ba19F]+ with an inductively coupled plasma-triple quadrupole-mass spectrometer (ICP-QQQ-MS). Method development involved the instrumental setup for Ba introduction and fluorine-specific tuning of lens and collision-reaction cell (CRC) parameters. An inorganic fluorine fraction was detected in a cyclonic dust sample from a municipal waste incineration plant as a peak above a broad background signal. The content was estimated through standard addition using a NaF solution to 2300 mgg−1. With a limit of detection (LOD) of 130 mg g−1, which was below the reported value for an electrothermal vaporization/inductively coupled plasma-mass spectrometry (ETV/ICP-MS) approach, acquiring [19F]+. The method's potential for fractionation analysis was demonstrated by analyzing polytetrafluoroethylene (PTFE) powder.
KW - PFAS
KW - ETV/ICP-QQQ-MS
KW - Solid sampling
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656766
DO - https://doi.org/10.1039/d6ja00014b
SN - 0267-9477
SP - 1
EP - 7
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65676
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - El Abbassi, Abdelouahad
A1 - Krenzer, Julius
A1 - Petrov, Eugene P.
A1 - Biesen, Lukas
A1 - Vasylyeva, Vera
A1 - Merzenich, Sarah
A1 - Resch-Genger, Ute
A1 - Müller, Thomas J. J.
T1 - Aroyl-S,N-ketene acetal-triarylamine bichromophores – intramolecular energy transfer and dual emission upon induced aggregation and encapsulation
N2 - Aroyl-S,N-ketene acetal-based bichromophores are synthesized by a catalytic aryl amination and their photophysics are studied in the solid state, in ethanol–water mixtures inducing aggregation, and after encapsulation in polystyrene nanoparticles. The dye substitution pattern controls aggregation-induced emission and intramolecular energy transfer efficiency, resulting in single-band or dual fluorescence and a strong increase in fluorescence quantum yield upon particle encapsulation.
KW - Fluorescence
KW - Dye
KW - Aggregation
KW - Photophysics
KW - Enhancement
KW - White light emission
KW - Energy transfer
KW - Quantum yield
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656700
DO - https://doi.org/10.1039/d5ra09361a
SN - 2046-2069
VL - 16
IS - 11
SP - 10255
EP - 10260
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65670
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - BOOK
A1 - Geburtig, Anja
A1 - Manier, G.
A1 - Cäsar, J.
A1 - Herlyn, J.
A1 - Hülsmann, Ph.
A1 - Köhl, M.
A1 - Reichert, Th.
A1 - Ruoss, H.
A1 - Rüther, N.
A1 - Schönlein, A.
T1 - Wasser und Materialeigenschaften
N2 - In der Gesellschaft für Umweltsimulation GUS e.V. erarbeiten Fachleute aus Wissenschaft und Industrie in freiwilliger Selbstverantwortung Leitfäden und Bücher zur, Umweltsimulation und zur Wirkungssimulation von Umwelteinflüssen.
Diese beschreiben den Stand der Technik bzw. Stand der Wissenschaft und dienen als Anleitung für Umweltingenieure und Personen, die sich in die Arbeitsgebiete Produktqualifikation und Umweltsimulation einarbeiten und einiesen wollen.
Folgende Themenschwerpunkte werden in diesem Leitfaden behandelt: Wasser und seine Eigenschaften, Phasenübergänge, Transportvorgänge, Änderung von Materialeigenschaften durch Wasser, Messmethoden.
KW - Wasser
KW - Materialien
PY - 2019
SN - 978-3-9818507-4-1
N1 - Belegexemplar liegt bei Frau Geburtig.
SP - 1
EP - 445
PB - Stober GmbH
CY - Eggenstein
AN - OPUS4-48325
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Wachtendorf, Volker
A1 - Geburtig, Anja
T1 - Alterungsvorgänge durch Bewitterung bei Beschichtungen und deren Untersuchung und Prüfung
T2 - 42. Fortbildungskurs SAH - Holzoberflächen in der Fassadengestaltung
CY - Weinfelden, Schweiz
DA - 2010-10-26
KW - Bewitterung
KW - Alterung
KW - Holz
PY - 2010
SN - 978-3-906703-26-8
SP - 29
EP - 38
CY - Zürich, Schweiz
AN - OPUS4-22601
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wachtendorf, Volker
A1 - Geburtig, Anja
T1 - Chemiluminescence for the early detection of weathering effects of coatings - Part II: Experimental set-up and examination
KW - Chemiluminescence
KW - Weathering
KW - Polymer
KW - Oxidation
PY - 2010
SN - 1547-0083
VL - 7
IS - 5
SP - 38
EP - 44
PB - Federation of Societies for Coatings Technology
CY - Blue Bell, Pa.
AN - OPUS4-21494
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CHAP
A1 - Geburtig, Anja
A1 - Wachtendorf, Volker
A1 - Trubiroha, P.
A1 - Zäh, M.
A1 - Schönlein, A.
A1 - Müller, A.
A1 - Vatahska, T.
A1 - Manier, G.
A1 - Reichert, T.
ED - White, C. C.
ED - Martin, J.
ED - Chapin, J.T.
T1 - Polypropylene numerical photoageing simulation by dose-response functions with respect to irradiation and temperature: vipquali project
N2 - The aim of the joint project ViPQuali (Virtual Product Qualification) was to describe a components ageing behaviour in a given environment, by numerical simulation.
Having chosen polypropylene (PP) as the material, which does not show sensitivity to moisture, the relevant weathering parameters of the doseresponse functions could be limited to spectral irradiance and temperature.
In artificial irradiation tests, for PP plates of varied stabiliser content, spectral sensitivity as well as temperature dependence of irradiation-caused crack formation was quantified. For that purpose, samples were exposed both to artificial weathering tests at various constant temperatures and to spectrally resolved irradiation. The temperature dependence could be modelled by an Arrhenius fit. For fitting the spectral sensitivity, a plateau function was chosen. Subsequently, the stabiliser content was parameterised and extrapolated.
The formed dose–response functions were incorporated into a Computational Fluid Dynamics (CFD) software program, simulating the environment of a sample within a Phoenix-exposed IP/DP (Instrument Panel/Door Panel box) box, based on sun position and weather conditions, including radiation interactions. Observed local effects as well as the general ageing advance of PP hats are compared with respect to simulation and experiment.
Resulting from this project, for this most simple example of PP of varied stabiliser content, the time to failure can be estimated for each weathering exposure environment with known time-resolved irradiance and temperature conditions.
PY - 2015
SN - 978-3-319-06033-0
SN - 978-3-319-06034-7
DO - https://doi.org/10.1007/978-3-319-06034-7_14
SP - Chapter 14, 215
EP - 229
PB - Springer
AN - OPUS4-32062
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Trubiroha, P.
A1 - Geburtig, Anja
A1 - Wachtendorf, Volker
ED - Reichert, T.
T1 - Surface temperatures of irradiated test specimens - decisive physical quantities and a largely unsolved problem
N2 - Temperature is an important parameter in weathering tests. In many (photo-)chemical degradation processes a Variation of the specimen temperature by A t = + 1 °C can cause a Variation of AP(property change) by ± 8%.
Since the early eighties it is well known that some types of black panel thermometers can show temperatures that are far below the maximum surface temperature of a black specimen. Although, there were precise requirements for the black coating of the BPT, a replacement by a white coating - depending on the design of the BPT - did not really change the temperature shown by the thermometer. There was no correlation between the BPT and the specimen surface temperature.
In Europe and later at ISO the so-called black- and white-standard thermometers BST/WST were introduced. Now, there are BST and WST (ISO) and there are thermally uninsulated and insulated BPT and WPT (ASTM), partly for artificial or for outdoor exposure. And there are other adventurous procedures to determine surface temperatures.
The different types of thermometers and different procedures will be discussed and it will be shown that there is no procedure which establishes a correlation between outdoor surface temperatures and surface temperatures in artificial exposure tests.
T2 - 6th European weathering symposium Natural and artificial ageing of polymers
CY - Bratislava, Slovak Republic
DA - 11.09.2013
PY - 2013
SN - 978-3-9813136-8-0
N1 - Serientitel: CEEES Publication – Series title: CEEES Publication
IS - 16
SP - 185
EP - 194
AN - OPUS4-31292
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Trubiroha, P.
A1 - Geburtig, Anja
A1 - Wachtendorf, Volker
ED - Reichert, T.
T1 - On the yet unsolved problem of the determination of precise surface temperatures of specimens exposed to natural and artificial weathering
N2 - The surface temperature of test specimens exposed to natural and artificial solar radiation are roughly ascertained with black standard thermometers BST and white standard thermometers WST. For the calibration of these thermometers a new European Standard prEN 16465 was published in 2015, describing the well-known contact method and a new contactless method with a pyrometer. It can be confirmed that the temperature calibrations according to the two methods provide different calibration results which are not interchangeable (which is already stated in the scope of this standard). The described contactless method to determine the surface temperature 'under radiation load' results in clearly too high temperatures. This paper tries to highlighting the reasons.
T2 - 7th European weathering symposium - Natural and artificial ageing of polymers
CY - Naples, Italy
DA - 16.09.2015
PY - 2015
SN - 978-3-9816286-6-1
N1 - Serientitel: CEEES Publication – Series title: CEEES Publication
IS - 17
SP - 23
EP - 36
AN - OPUS4-34351
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Geburtig, Anja
T1 - A new weathering device for plastic containers with parallel impact of dangerous liquids
N2 - For plastic packaging, both weathering and Chemical exposure are well known, slow-going damaging scenarios, which themselves are sufficiently covered in relevant transport regulations, but treated there separately.
In previous work, it has been shown that both can act synergistically, resulting in leakage failure after only six month outdoor exposure in Berlin/Germany.
A new weathering device is presented which enables combined exposure of whole components under controlled laboratory conditions. This device allows exposure of an up to 60 litres Container which is filled with dangerous liquid. By using a collecting drip pan and an extractor hood, safety is guaranteed, also in case of leakage failure. Irradiance homogeneity is realized by rotating the Container between two opposed lamp fields consisting of vertically arranged UV fluorescent lamps. Using UVA 340nm lamps with spectral emission mainly between 290 and 380 nm, the short wave ränge of global solar radiation is simulated very precisely. UV irradiance is constantly 60 W/m2, thus it is a bit higher than maximum global solar radiation in the considered UV ränge. Radiation heating is knowingly excluded, avoiding heat production that potentially could be critical for included dangerous liquids.
Adjusting constant temperature of 40 °C, chosen conditions aim at worst case outdoor conditions, for uncolored Containers.
T2 - 27th IAPRI Symposium on packaging
CY - Valencia, Spain
DA - 08.06.2015
KW - Weathering exposure
KW - Chemical exposure
KW - Plastic packaging
PY - 2015
SN - 978-84-943398-4-4
SP - 1
EP - 5
AN - OPUS4-33488
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Engelking, Lorenz
A1 - Eissel, A.
A1 - Madia, Mauro
A1 - Schröpfer, Dirk
A1 - Treutler, K.
A1 - Kruse, Julius
A1 - Kannengießer, Thomas
A1 - Wesling, V.
T1 - Influence of ultrasonic-assisted milling on surface integrity of additively manufactured components using MSG processes
N2 - Additive manufacturing (AM) is increasingly used for producing complex metallic components. Subsequent machining is essential to achieve final geometries and surface conditions. The resulting surface integrity, particularly the near-surface residual stress state, plays a crucial role in component performance and fatigue life. This study investigates the potential of ultrasonic-assisted milling (USAM), a hybrid machining process, to improve surface integrity and machinability compared to conventional milling (CM). Three materials were investigated, two difficult-to-cut materials CoCr26Ni9Mo5W and FeNi36 and a low-alloy steel S355J2C. The CoCr26Ni9Mo5W and FeNi36 were additively manufactured via Directed Energy Deposition (DED)-Arc and then machined with varying cutting speeds and feed rates within a Design of Experiments. USAM exhibited enhanced machinability and surface integrity, particularly at low cutting speeds, by reducing cutting forces up to 40% and shifting near-surface residual stresses from tensile to compressive. For S355J2C, USAM reduced cutting forces by approximately 45% and induced near-surface compressive residual stresses up to approximately −700 MPa. Rotating bending tests (DIN50100) show that USAM increases the technical fatigue limit from 307 MPa (CM) to 341 MPa (USAM), i.e., by ∼11%. These findings highlight the advantages of ultrasonic assistance in post-AM machining, offering enhanced fatigue performance and surface quality for various metallic materials.
T2 - 4th International Conference on Advanced Joining Processes 2025
CY - Coimbra, Portugal
DA - 16.10.2025
KW - Ultrasonic-assisted milling
KW - Residual stress
KW - Surface integrity
PY - 2026
DO - https://doi.org/10.1177/14644207261416395
SP - 1
EP - 12
PB - Sage Journals
AN - OPUS4-65682
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Jesus, Vinicius D.
A1 - Merizio, Leonnam G.
A1 - Galleani, Gustavo
A1 - Raffy, Guillaume
A1 - Carpentier, Mathis
A1 - Petit, Yannick
A1 - Cardinal, Thierry
A1 - de Camargo, Andrea S. S.
T1 - Energy transfer from Ag species to Nd 3+ in Ga–fluoride–phosphate glasses: near-infrared emission enhancement via controlled heat treatment and femtosecond laser inscription
N2 - Gallium fluoride–phosphate glasses are promising materials with wide optical transmission window, high volumetric density, and the ability to accommodate high concentrations of rare earth dopant ions within a tailored fluoride-rich coordination environment, resulting in high emission cross sections. In this work, the compositional system 25Ga(PO3)3–20ZnF2–30BaF2–(25–x–y)SrF2–xAgNO3–yNdF3 (x = 0–10 mol%, y = 0 or 1 mol%) was studied to understand how silver species affect the near-infrared (NIR) emission of Nd3+ ions, when the glasses are subjected to controlled heat treatment and to femtosecond direct laser writing (DLW). The glasses were obtained via the melt-quenching technique and characterized by DSC, XRD, UV-Vis-NIR absorption, and PL spectroscopy. The as-prepared glasses show broad UV-Vis excitation and emission bands arising from the coexistence of Ag+ ions and ionic Ag pairs. In samples with 10 mol% Ag+, brownish coloration and modified emission profiles indicated Ag nanoparticle formation at the surface. Heat treatment promoted the conversion of isolated Ag+ into ionic pairs, producing broadband emissions tunable by excitation wavelength and Ag+ concentration. In co-doped samples, Nd3+ introduced absorption dips in the Ag-related UV-Vis bands, consistent with energy transfer, which was further confirmed by shortened Ag excited-state lifetimes and increased Nd3+ NIR emission under UVVis excitation. In order to control the spatial distribution and size of Ag aggregates (nanoclusters, NCs) and to increase the energy transfer efficiency to Nd3+, femtosecond direct laser writing (DLW) was employed to co-doped glasses with 3 and 5 mol% Ag+. This approach enabled three-dimensional localized growth of Ag NCs with sub-micron spatial control. In the laser processed regions, the NIR emissions of Nd3+ at 900 and 1060 nm were significantly enhanced, clearly evidencing enhanced energy transfer from the localized laserinduced Ag-NCs to the Nd3+ ions. These findings suggest the possibility of tailoring high optical contrast near-IR emissions in glasses, enabling progress in advanced photonic applications.
KW - Neodymium
KW - Silver
KW - Fluoride phosphate glasses
KW - Direct laser writing
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656888
DO - https://doi.org/10.1039/d5ma01430a
SN - 2633-5409
SP - 1
EP - 14
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65688
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pittrich, Tim
A1 - Peters, Simon
A1 - Meschke, Günther
A1 - Weise, Frank
A1 - Stelzner, Ludwig
T1 - Thermally induced moisture transport in concrete with different types of blended Portland cement studied by 1H-NMR relaxometry
N2 - Clinker-reduced cements are gaining in popularity as part of efforts to lower the construction industry’s CO2 footprint. Past studies showed that utilization of these cements negatively influences the fire-induced spalling behavior of concrete, which is highly influenced by thermohydraulic damage mechanisms. Therefore, thermally induced moisture transport in normal strength concretes made with different types of blended cements (CEM I, CEM II/A-LL, CEM III/A and CEM II/B-Q) was investigated by means of 1H-NMR relaxometry in combination with supportive side investigations concerning permeability and porosity. In addition, a numerical model was used to analyze in-situ moisture development during high temperature exposure. The results show that the cement type influences both initial moisture content and pore size-specific moisture distribution. This was primarily reflected in an increased water content in CEM III/A and CEM II/B-Q concretes as well as a comparable high gel pore water fraction in CEM II/B-Q concrete before heating. After heating, a similar degree of pore coarsening from gel to capillary pore was observed in all samples. Although the measurements were only conducted after, not during, high temperature exposure, the depth of the drying front and the extent of the moisture clog could be determined. With the additional numerical analysis, it can be assumed that during high temperature load, the drying front is less advanced and the moisture clog even more pronounced. In conclusion, it can be stated that the increased spalling susceptibility in blended cement concrete is caused by the lower initial permeability and increased moisture content.
KW - Fire concrete spalling
KW - Thermally induced moisture transport
KW - Blended cements
KW - 1H-NMR
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656846
DO - https://doi.org/10.1617/s11527-026-03025-4
SN - 1359-5997
VL - 59
IS - 3
SP - 1
EP - 20
PB - Springer Science and Business Media LLC
AN - OPUS4-65684
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scharf-Wildenhain, R.
A1 - Engelking, Lorenz
A1 - Hälsig, A.
A1 - Schröpfer, Dirk
A1 - Kannengießer, Thomas
A1 - Hensel, J.
T1 - Influence of build‑up height on residual stresses in additive repair and modification using DED‑Arc with high‑strength filler metals
N2 - Directed energy deposition (DED)-Arc is suitable for the hybrid additive manufacturing, modification and repair of large metal components with high deposition rates. Residual stresses and distortion are of central importance when characterizing the manufactured components and the sensitive transition area between additive manufactured (AM) component and semifinished product. Residual stresses caused by the thermal cycles during the manufacturing process can impair the mechanical properties of the manufactured parts and can lead to component failure, especially for high-strength steels. Therefore, understanding and controlling residual stresses, when combining different base and feedstock materials, is critical to improve the quality and efficiency of the hybrid DED-Arc process. This article deals with the influence of the build-up height on the residual stress distribution of additively manufactured components with a selected base and feedstock material from commercial high-strength steels. Using a robot-assisted DED-system and a controlled short arc, AM welding experiments were carried out with close to the application parameters at working temperature (200 °C) and heat input (650 kJ/m). Five hybrid AM specimens (AM wall on upright structural steel plate) were produced using a one bead per layer strategy and selected AM-wall heights between 15 and 300 mm. The influence of the AM build height on the longitudinal residual stress in the whole hybrid AM specimen (in welding direction) was analyzed and discussed. All experiments exhibit comparable stress distributions in the area of the substrate plate up to the heat-affected zone (HAZ) and the transition zone, regardless of the building height. The height significantly influences the residual stress distribution of the deposited AM-component. Tensile residual stresses with a maximum range between 300and 400 MPa were always found in the last approx. 18 component layers (upper 40 mm). This is due to restraint of the shrinking of the top layers by the layers below. The lower layers show homogeneous residual stress distributions characterized by low compressive stresses due to the process-related tempering during the deposition of each layer on top of each other. As a result, the significant difference between the various AM build-up heights of the hybrid AM specimens is the extent (or height) of this tempered zone with low compressive stresses. These correlations contribute to the understanding of residual stress development with increasing structure height or ratio of component heights of substrate semi-finished product and AM component in hybrid additive manufacturing.
T2 - 78th IIW Annual Assembly and International Conference
CY - Genoa, Italy
DA - 22.06.2025
KW - DED-Arc
KW - Residual stress
KW - Heat control
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656793
DO - https://doi.org/10.1007/s40194-026-02417-y
SN - 1878-6669
SP - 1
EP - 12
PB - Spriner
AN - OPUS4-65679
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fabry, Çağtay
A1 - Pittner, Andreas
A1 - Kaplan, Alexander
A1 - Rethmeier, Michael
T1 - Digitalisation and Carbon Footprint Evaluation of Gas Metal Arc Welding and Wire-Arc Directed Energy Deposition
N2 - This paper showcases how a holistic approach to digitalisation enables data-driven welding applications, exemplarily for a gas metal arc welding (GMAW) laboratory. The workflow integrates advanced process monitoring, synchronised multi-sensor data acquisition and tools for data analytics. A welding domain-specific data exchange format weldx is presented that unifies and aggregates the data sets acquired during process monitoring with final component quality metrics, supporting reuse, traceability, and reproducibility. Two case studies illustrate the approach. First, GMAW parameters are adaptively adjusted according to local seam geometry to compensate joint-preparation deviations from nominal values typical for large-scale steel fabrication. Second, the seamless data aggregation along the welding production chain enables an automatic life-cycle assessment (LCA), quantifying the environmental impacts of additive manufacturing with DED Arc/M and attributing the dominant contributors to the carbon footprint. Collectively, the results indicate that a fully integrated experimental set-up together with standardised data structures and scalable analytics can couple monitoring, control, and sustainability, thereby realising the potential of digitalisation for high-quality and environmentally informed welding production.
KW - Digitalisation
KW - Arc welding
KW - DED-arc
KW - Life Cycle Assessment
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656812
DO - https://doi.org/10.1088/1757-899X/1342/1/012067
SN - 1757-8981
VL - 1342
IS - 1
SP - 1
EP - 15
PB - IOP Publishing
AN - OPUS4-65681
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Wachtendorf, Volker
A1 - Geburtig, Anja
T1 - Chancen und Grenzen der Verkürzung von Bewitterungstests durch empfindliche Chemilumineszenz-Detektion
N2 - Eine Verkürzung der Dauer von Bewitterungsversuchen kann durch eine empfindlichere Detektion der Bewitterungseffekte erreicht werden als sie konventionell benützt wird. Eine solche besonders empfindliche Detektionsmethode stellt die Chemilumineszenz dar. Die Verkürzung durch empfindliche Detektion muss jedoch gleichzeitig der Bedingung genügen, ausreichend gute Rangkorrelation zu Bewitterungseffekten unter Anwendungsbedingungen zu zeigen. In diesem Spannungsfeld sollen die Möglichkeiten der Chemiluminiszenz-Detektion beleuchtet werden.
T2 - DFO Qualitätstage 2008
CY - Fürth, Deutschland
DA - 2008-10-07
KW - Chemilumineszenz
KW - Bewitterung
KW - Verkürzung
KW - empfindlicher Nachweis
PY - 2008
SN - 978-3-89943-072-1
SP - 105
EP - 120
PB - DFO
CY - Fürth
AN - OPUS4-18328
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Wachtendorf, Volker
A1 - Geburtig, Anja
ED - Ziegahn, K.-F.
T1 - Zusammenhang von molekularen Alterungsvorgängen und beobachtbaren Eigenschaftsänderungen bei der Bewitterung von Polymeren
T2 - 39. Jahrestagung der GUS 2010 - Umweltflüsse erfassen, simulieren, bewerten
CY - Stutensee, Deutschland
DA - 2010-03-17
KW - Bewitterung
KW - Alterung
KW - Eigenschaftsänderung
KW - Korrelation
PY - 2010
SN - 978-3-9813136-0-4
SP - 45
EP - 55
PB - DWS Werbeagentur und Verlag GmbH
CY - Pfinztal
AN - OPUS4-21047
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Wachtendorf, Volker
A1 - Geburtig, Anja
T1 - Untersuchung der Veränderung der Kratzfestigkeit und Reflow-Fähigkeit von Karosserie-Klarlacken als Folge der Auslagerung in Jacksonville und nachgestellter Laborbewitterung
T2 - DFO Qualitätstage 2005 - Moderne Verfahren zur Oberflächencharakterisierung
CY - Berlin, Deutschland
DA - 2005-10-25
KW - Bewitterung
KW - Kratzfestigkeit
KW - Kratzbeständigkeit
KW - Reflow
KW - Weißlichtinterferenz
KW - Rauhigkeit
PY - 2005
SN - 3-89943-062-X
SP - 88
EP - 102
PB - DFO
CY - Düsseldorf
AN - OPUS4-11216
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Geburtig, Anja
A1 - Wachtendorf, Volker
T1 - Determination of the spectral sensitivity and temperature dependence of polypropylene crack formation caused by UV-irradiation
N2 - For polypropylene of varied stabilization, spectral sensitivity as well as temperature dependence of irradiation caused crack formation was determined in artificial irradiation tests. UV radiant exposure HUV necessary to generate crack formation was measured both in spectrally dispersed irradiation and artificial irradiation in a Fluorescent UV lamp device. Dependencies were fitted to a plateau function and an Arrhenius function, respectively, to describe the action of irradiation by response functions. Applied to weather data from Phoenix, the results were compared with respective outdoor exposure results.
KW - Weathering
KW - UV
KW - Temperature
KW - Numerical simulation
PY - 2010
DO - https://doi.org/10.1016/j.polymdegradstab.2010.06.014
SN - 0141-3910
SN - 1873-2321
VL - 95
IS - 10
SP - 2118
EP - 2123
PB - Applied Science Publ.
CY - London
AN - OPUS4-21913
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wachtendorf, Volker
A1 - Geburtig, Anja
T1 - Chemiluminescence for the early detection of weathering effects of coatings - Part I: Fundamentals
KW - Chemiluminescence
KW - Weathering
KW - Polymer
KW - Oxidation
PY - 2010
SN - 1547-0083
VL - 7
IS - 4
SP - 66
EP - 71
PB - Federation of Societies for Coatings Technology
CY - Blue Bell, Pa.
AN - OPUS4-21493
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Lüthi, A.
A1 - Fäh, D.
A1 - Wachtendorf, Volker
A1 - Geburtig, Anja
ED - Reichert, T.
ED - Halafka, S.
T1 - Recent Proposals for Weathering Reference Materials as Discussed by DIN and VDA
T2 - 1st European Weathering Symposium (EWS-1) ; 23rd Colloquium of Danubian Countries on Natural and Artificial Ageing of Polymers
CY - Prague, Czech Republic
DA - 2003-09-25
KW - Reference material
KW - ORWET
KW - Crack
KW - Climatic
KW - ADF test
KW - Spectral sensitivity
KW - Referenzmaterial
KW - Riss
KW - Klimatische Beständigkeit
PY - 2003
SN - 3-9808382-3-4
SP - 1(?)
EP - 12(?)
PB - Gesellschaft für Umweltsimulation e.V.
CY - Pfinztal
AN - OPUS4-2682
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Geburtig, Anja
A1 - Wachtendorf, Volker
A1 - Trubiroha, Peter
T1 - Two New Weathering Reference Materials - Monitors for Weathering Exposure
T2 - 3rd Service Life Symposium
CY - Sedona, AZ, USA
DA - 2004-02-01
KW - Weathering
KW - Reference material
KW - WRM
KW - UV
KW - Radiance
KW - Crack
KW - JIS K7200
KW - Humidity
KW - Bewitterung
KW - Referenzmaterial
KW - Riss
KW - Bestrahlung
KW - Luftfeuchte
PY - 2005
SN - 0-934010-60-9
SP - 253
EP - 258
PB - Federation of Societies for Coatings Technology
CY - Philadelphia
AN - OPUS4-13712
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -