TY - JOUR A1 - Costa e Silva, A. A1 - Coelho, D. A1 - Kranzmann, Axel A1 - Rizzo, Fernando T1 - Simulation of Fe-Cr-X Alloy Exposed to an Oxyfuel Combustion Atmosphere at 600°C N2 - In coal-fired power plants using oxyfuel combustion process with carbon capture and sequestration, instead of air, a mixture of oxygen and recirculated flue gas is injected in the boiler. A series of steels were exposed to CO2-SO2-Ar-H2O gas mixtures at 600 °C for 1000 h to compare their high temperature corrosion behavior. During the corrosion process, carburization, decarburization and recrystallization were observed underneath the oxide scale depending on the gas mixture and alloy composition. The conditions that lead to carburization are not yet completely understood, but decarburization can be simulated using thermodynamic and kinetic models. In this work, the results of these simulations are compared with measured values for one of the alloys that displayed a decarburized region. Since the mobility of carbon in the scale is not known, two strategies were adopted: simulation of alloy-atmosphere contact; and estimation of the carbon flux to produce the observed decarburization. The second approach might give an insight on how permeable to carbon the scale is. KW - CALPHAD approach KW - Corrosion KW - Decarburization KW - DICTRA modeling KW - Experimental kinetics PY - 2016 U6 - https://doi.org/10.1007/s11669-015-0421-3 SN - 1547-7037 VL - 37 IS - 1 SP - 19 EP - 24 PB - ASTM International AN - OPUS4-50612 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Simone A1 - Friedrich, Jörg A1 - Hidde, Gundula A1 - Farag, Zeinab R. A1 - Moustapha, Moustapha E. A1 - Azzam, Maged M. T1 - Promotion of adhesion of green flame retardant coatings onto polyolefins by depositing ultra-thin plasma polymer films: A critical review N2 - Various methods have been used for introducing fire retardant additives into polymers. Deposition of thick fire retardant coatings directly onto polymer substrates is an alternative technique. An important Advantage of the coating technique is the preservation of the physical and chemical integrity of the polymer material. Moreover, the fire retardancy of the polymer materials can be achieved following their production. Suitable coating materials are inorganics, intumescent, char-forming, oxygendiluting, and cooling or radical quenching layers. The most important problem is to achieve sufficient coating thickness to withstand the direct attack of flame and to protect the polymer bulk from pyrolysis, otherwise blistering of coating, caused by emitted pyrolysis gases, is often observed. To avoid blistering of coating, the adhesion between polyolefin Substrate and fire retardant coating has to be extraordinarily high. In order to achieve such a high level of adhesion, the polymer surface has to be modified with adhesion-promoting functional groups. The deposition of thin plasma polymers as adhesion-promoting layers with NH2, OH or COOH groups has been the most suited method. These functional groups are able to form covalent bonds and other interactions between the fire-resistant coating and the plasma-modified polyolefin substrate. Additionally, the plasma polymer counteracts the strong mechanical stresses in the laminate on exposure to high temperatures by its flexibility. The thick fire retardant coatings were chosen based on “green” ecological aspects to avoid flame-initiated emission of toxic or corrosive gases and remains of toxic char. KW - Flame retardant KW - Adhesion KW - Coating PY - 2016 U6 - https://doi.org/10.7569/RAA.2016.097314 SN - 2168-0965 SN - 2168-0973 VL - 4 IS - 4 SP - 417 EP - 447 PB - Scrivener Publishing LLC AN - OPUS4-48164 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Huang, S. G. A1 - Vleugels, J. A1 - Mohrbacher, H. A1 - Woydt, Mathias T1 - Microstructure and mechanical properties of NbC matrix cermets using Ni containing metal binder N2 - The current study reports on the effect of the addition of Al metal and secondary refractory carbides on the microstructure and mechanical properties of Ni bonded NbC matrix cermets. KW - NbC KW - Niobium carbide KW - Hardness KW - Hard materials PY - 2016 U6 - https://doi.org/10.1016/j.mprp.2016.05.009 VL - 71 IS - 5 SP - 349 EP - 355 PB - Elsevier Ltd. AN - OPUS4-44623 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hofmann, D. A1 - Rahammer, M. A1 - Liewald, M. A1 - Heckel, Thomas A1 - Huppmann, M. T1 - Vergleich von zerstörungsfreien und zerstörenden Prüfungen dünner Strukturklebungen in der Umformtechnik T1 - Comparison of non destructive and destructive tests of thin structural bonds in the forming technology N2 - Der vorliegende Fachartikel stellt die wichtigsten zerstörungsfreien Prüfmethoden zur Qualitätssicherung von dünnen Strukturklebungen vor. Auf diese Weise wird ersichtlich, welche Methoden neben der zerstörenden Prüfung von dünnen Strukturklebungen eingesetzt werden können, um einen Haftfestigkeitsverlust zu detektieren. Steigende Leichtbau- und Dämpfungsanforderungen an großflächige Blechbauteile sorgen trotz erhöhter Kosten für einen zunehmenden Einsatz von modernen hybriden Schichtverbundwerkstoffen in zahlreichen Konstruktionsanwendungen. In der Luft- und Raumfahrtindustrie gehören solche Werkstoffe seit geraumer Zeit zum aktuellen Stand der Technik, wohingegen diese Werkstoffkonzepte in der mobilen Großserie derzeit nur selten zum Einsatz kommen. Neben dem Materialversagen der einzelnen Schichten von Schichtverbundwerkstoffen spielt das interlaminare Versagen der Schichten untereinander eine entscheidende Rolle. In der Umformtechnik ist es möglich, dass die polymere Zwischenschicht und das Deckblech nach der Umformung noch in Kontakt stehen, obwohl die Scherfestigkeit bereits überschritten wurde. Dieser Kraftschluss der beiden Fügepartner resultiert aus den schwachen Van-der-Waals-Kräften, die eine eindeutige Detektion mit Hilfe von zerstörungsfreier Prüfung erschweren. Die vorliegende Publikation soll die Eignung diverser zerstörungsfreier Prüfverfahren auf die Detektion von sogenannten „kissing bonds“ (schwaches Anhaften der Schichten nach Versagen der Verbindung) überprüfen. KW - Zerstörungsfreie Prüfung KW - Zerstörende Prüfung KW - Klebeverbindungen KW - Umformtechnik PY - 2016 U6 - https://doi.org/10.3139/120.110949 SN - 0025-5300 VL - 58 IS - 11-12 SP - 975 EP - 981 PB - Carl Hanser Verlag GmbH & Co. KG CY - München AN - OPUS4-43620 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Koller, C. S. A1 - Hönow, B. A1 - Bellon, Carsten A1 - Börner, F. D. T1 - Detection of vertical movement of fluids behind the casing of groundwater observation wells N2 - Focus of this work is the detection of vertical movements behind the casing of groundwater observation wells within the seal. A new multi-methodical and azimuthal logging tool, named Azimuthal-Annulus-Convection-Identification (AACI)-Log has been developed and tested. The measurement concept of this probe is based on the combination of three azimuthal measuring logs – contact temperature on the inside of the casing wall, backscattered gamma-rays (gamma-gamma density), and natural radioactivity (gamma ray). Consequently, a direction-oriented image of the annular space can be derived. Not only the reason (void, potential channel) but also the resulting effect (vertical movement of fluids) can be detected with the Azimuthal-Annulus-Convection (AACI) – Log at the same time. KW - Azimuthal temperature field KW - Vertical fluid movement KW - Groundwater observation well KW - Azimuthal well logging KW - Direction-oriented image KW - Annular space PY - 2016 U6 - https://doi.org/10.1504/IJHST.2016.079336 SN - 2042-7808 VL - 6 IS - 4 SP - 301 EP - 330 PB - Inderscience Publishers CY - Olney, UK AN - OPUS4-43158 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Deußing, G. A1 - Dümichen, Erik A1 - Braun, Ulrike T1 - Polymeranalytik Intelligent kombiniert N2 - Durch die intelligente Anbindung an die Stir Bar Sorptive Extraction (SBSE) lassen sich Zersetzungsprodukte der thermogravimetrischen Analyse (TGA) von Polymeren auf effiziente Weise anreichern, auftrennen und mittels GC/MS identifizieren. KW - Thermische Degradation KW - Mikroplastik PY - 2016 UR - http://www.gerstel.cn/de/GA51_Polymeranalytik.htm IS - 51 SP - 9 EP - 11 PB - Gerstel AN - OPUS4-42146 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stockmann, Jörg M. A1 - Hertwig, Andreas A1 - Beck, Uwe T1 - Visualization of low-contrast surface modifications: Thin films, printed pattern, laser-induced changes, imperfections, impurities, and degradation N2 - Visualization of surface modifications may be very challenging for coating/substrate systems of either almost identical optical constants, e.g. transparent films on substrates of the same material, or minor film thickness, substance quantity and affected area, e.g. ultra-thin or island films. Methods for visualization are optical microscopy (OM), imaging ellipsometry (IE), and referenced spectroscopic ellipsometry (RSE). Imaging ellipsometry operates at oblique incidence near Brewster angle of the bare, clean or unmodified substrate. In this configuration, reflected intensities are rather weak. However, the contrast to add-on and sub-off features may be superior. Referenced spectroscopic ellipsometry operates in a two-sample configuration but with much higher intensities. In many cases, both ellipsometric techniques reveal and visualize thin films, printed-pattern, laser-induced changes, and impurities better than optical microscopy. In particular for stratified homogeneous modifications, ellipsometric techniques give access to modelling and hence thickness determination. Modifications under investigation are polymer foil residue on silicon, laser-induced changes of ta-C:H coatings on 100Cr6 steel, imperfections of ta-C:H on thermal silicon oxide, degradation of glass, thin film tin oxide pattern on silicon, printed and dried pattern of liquids such as deionized water, cleaning agents, and dissolved silicone. © 2016 Elsevier B.V. All rights reserved. T2 - International Conference on Spectroscopic Ellipsometry (ICSE-7) CY - Berlin, Germany DA - 06.06.2016 KW - Optical microscopy (OM) KW - Imaging ellipsometry (IE) KW - Referenced spectroscopic ellipsometry (RSE) KW - Thin films KW - Impurities KW - Degradation PY - 2016 U6 - https://doi.org/10.1016/j.apsusc.2016.10.145 SN - 0196-4332 VL - 2017 IS - 421 SP - 807 EP - 812 PB - Elsevier B.V. AN - OPUS4-42136 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartoschewitz, R. A1 - Appel, P. A1 - Barrat, J.-A. A1 - Bischoff, A. A1 - Caffee, M.W. A1 - Franchi, I.A. A1 - Gabelica, Z. A1 - Greenwood, R.C. A1 - Harir, M. A1 - Harries, D. A1 - Hochleitner, R. A1 - Hopp, J. A1 - Laubenstein, M. A1 - Mader, B. A1 - Marques, R. A1 - Morlok, A. A1 - Nolze, Gert A1 - Prudêncio, M.I. A1 - Rochette, P. A1 - Ruf, A. A1 - Schmitt-Kopplin, P. A1 - Seemann, E. A1 - Szurgot, M. A1 - Tagle, R. A1 - Wach, R.A. A1 - Welten, K. C. A1 - Weyrauch, M. A1 - Wimmer, K. T1 - The Braunschweig meteorite − a recent L6 chondrite fall in Germany N2 - On April 23rd 2013 at 2:07 a.m., a 1.3 kg meteorite fell in the Braunschweig suburb Melverode (52° 13′ 32.19″ N. 10° 31′ 11.60″ E). Its estimated velocity was 250 km/h and it formed an impact pit in the concrete fall site with a diameter of 7 cm and a depth of 3 cm. Radial dust striae are present around the impact pit. As a result of the impact, the meteorite disintegrated into several hundred fragments with masses up to 214 g. The meteorite is a typical L6 chondrite, moderately shocked (S4) – but with a remarkably high porosity (up to 20 vol%). The meteorite was ejected from its parent body as an object with a radius of about 10–15 cm (15–50 kg). The U,Th-He gas retention age of ∼550 Ma overlaps with the main impact event on the L-chondrite parent body ∼470 Ma ago that is recorded by many shocked L chondrites. The preferred cosmic-ray exposure age derived from production of radionuclides and noble gas isotopes is (6.0 ± 1.3) Ma. KW - Braunschweig meteorite KW - L chondrite KW - Fall reconstruction KW - Petrology and mineralogy KW - Organic matter KW - IR spectroscopy KW - Bulk chemistry KW - Radionuclides KW - Noble gas isotopes KW - Specific heat PY - 2016 U6 - https://doi.org/10.1016/j.chemer.2016.10.004 SN - 0009-2819 SN - 1611-5864 VL - 77 IS - 1 SP - 207 EP - 224 AN - OPUS4-42018 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martin-Sanchez, Pedro Maria A1 - Gorbushina, Anna A1 - Toepel, Jörg T1 - Quantification of microbial load in diesel storage tanks using culture- and qPCR-based approaches N2 - Microbial contamination of fuels, associated with a wide variety of bacteria and fungi, leads to decreased product quality and can compromise equipment performance by biofouling and microbiologically influenced corrosion of pipelines and storage tanks. Detection and quantification of biomass are critical in monitoring fuel systems for an early detection of microbial outbreaks. The aims of this study are (i) to quantify bacterial and fungal contamination in samples from diesel storage tanks of petrol stations, using both culture dependent- and culture independent (qPCR) approaches, and (ii) to analyse the diversity of cultivable diesel-contaminating microorganisms with the purpose to create a strain collection for further use in biodeterioration experiments. Both methodological approaches revealed a high microbial contamination in all studied samples, with the bacterial load being much higher than the fungal load. The diversity of cultivable microorganisms was rather low. Based on criteria of abundance and fuel degradation potential, the most relevant microorganisms were identified as bacteria of genera Bacillus, Citrobacter, Burkholderia and Acetobacter, the filamentous fungi Paecilomyces variotii and Pseudallescheria boydii, and a Dipodascaceae yeast. Furthermore the validity and utility of qPCR-based methods are discussed. KW - Fuel contamination KW - Biofouling KW - Cultivation KW - Real-time qPCR KW - Bacteria KW - Fungi PY - 2016 U6 - https://doi.org/10.1016/j.ibiod.2016.04.009 SN - 0964-8305 SN - 1879-0208 VL - 126 SP - 216 EP - 223 PB - Elsevier Ltd. AN - OPUS4-41260 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kruschwitz, Sabine A1 - Prinz, Carsten A1 - Zimathies, Annett T1 - Study into the correlation of dominant pore throat size and SIP N2 - There is currently a debate within the SIP community about the characteristic textural length scale controlling relaxation time of consolidated porousmedia.One idea is that the relaxation time is dominated by the pore throat size distribution or more specifically the modal pore throat size as determined in mercury intrusion capillary pressure tests. Recently new studies on inverting pore size distributions from SIP data were published implying that the relaxation mechanisms and controlling length scale are well understood. In contrast new analytical model studies based on the Marshall-Madden membrane polarization theory suggested that two relaxation processes might compete: the one along the short narrow pore (the throat) with one across the wider pore in case the narrow pores become relatively long. This paper presents a first systematically focused study into the relationship of pore throat sizes and SIP relaxation times. The generality of predicted trends is investigated across a wide range of materials differing considerably in chemical composition, specific surface and pore space characteristics. Three different groups of relaxation behaviors can be clearly distinguished. The different behaviors are related to clay content and type, carbonate content, size of the grains and the wide pores in the samples. KW - Textural controls KW - Spectral induced polarization KW - Relaxation time KW - Pore throat size KW - Consolidated materials KW - Membrane polarization PY - 2016 U6 - https://doi.org/10.1016/j.jappgeo.2016.07.007 VL - 135 SP - 375 EP - 386 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-40346 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -