TY - CONF A1 - Reinsch, Stefan A1 - Dreßler, Martin A1 - Nofz, Marianne A1 - Pauli, Jutta A1 - Jäger, Christian A1 - Scholz, G. ED - Krämer, V. T1 - Phasentransformationen von anorganisch modifizierten Alumo-Xerogelen T2 - Jahrestagung der Gesellschaft für Thermische Analyse e.V. CY - Augsburg, Deutschland DA - 2003-09-15 PY - 2003 SP - 1 EP - 2 AN - OPUS4-2668 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bücker, Michael A1 - Böcker, Wolfgang D. G. A1 - Reinsch, Stefan A1 - Unger, Brita T1 - Holzmodifikation durch Tränkung mit Nanopartikeln T2 - Tagung "Rosenheimer Fenstertage 2004" CY - Rosenheim, Deutschland DA - 2004-01-01 KW - Holzmodifikation KW - Sol-Gel KW - Tränkverfahren KW - Holzschutz PY - 2004 SP - 23 EP - 26 PB - Institut für Fenstertechnik CY - Rosenheim AN - OPUS4-4487 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Beziehungen zwischen Zusammensetzung und thermischen Eigenschaften von Alumo-Xerogelen T2 - Jahrestagung der Gesellschaft für thermische Analyse (GEFTA) CY - Braunschweig, Germany DA - 2004-10-04 PY - 2004 AN - OPUS4-5620 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Thermomechanisches Verhalten wasserhaltiger Glasschmelzen - Herstellung von Gläsern mit mittleren Wassergehalten T2 - Workshop Wasser im Glas CY - Berlin, Germany DA - 2004-12-08 PY - 2004 AN - OPUS4-5733 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmelzer, J.W.P. A1 - Potapov, O. V. A1 - Fokin, V. M. A1 - Müller, Ralf A1 - Reinsch, Stefan T1 - The effect of elastic stress and relaxation on crystal nucleation in lithium disilicate glass N2 - In the framework of a general theoretical approach recently developed, the effect of elastic stresses on the rate of nucleation of crystallites of critical sizes in the process of crystallization of lithium disilicate glasses is studied. Hereby both the evolution of elastic stresses – due to changes in the specific volume of the crystallizing system (i.e., differences in the densities of the melt and the crystal) – and their relaxation – connected with viscous flow – are taken into consideration. If the classical theory of nucleation is employed for the determination of the nucleation rates (modified by taking into account elastic stresses), elastic stresses may lead, for the system under consideration, to a decrease of the nucleation rate by up to two orders of magnitude. As shown, the theory allows an at least qualitatively correct incorporation of the effect of elastic stresses and stress relaxation into the description of nucleation phenomena in glass-forming melts. PY - 2004 DO - https://doi.org/10.1016/j.jnoncrysol.2003.10.002 SN - 0022-3093 VL - 333 IS - 2 SP - 150 EP - 160 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-6236 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bücker, Michael A1 - Böcker, Wolfgang D. G. A1 - Reinsch, Stefan A1 - Unger, Brita T1 - Alternativer Holzschutz KW - Holzschutz KW - Kieselsol KW - Biozide KW - Sol-Gel-Prozess PY - 2004 SN - 1435-1854 IS - 11 SP - 77 EP - 80 PB - Verl. f. Fachpublizistik CY - Stuttgart AN - OPUS4-6333 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wondraczek, L. A1 - Reinsch, Stefan A1 - Gaber, Martin A1 - Deubener, J. A1 - Müller, Ralf A1 - Komatsu, T. T1 - Nano-crystalline germanate glass-ceramics T2 - 78. Glastechnische Tagung CY - Nürnberg, Deutschland DA - 2004-06-07 PY - 2004 SP - 37 EP - 40 PB - Deutsche Glastechnische Gesellschaft CY - Offenbach AN - OPUS4-6953 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Phasentransformationen von anorganisch modifizierten Alumo-Xerogelen T2 - Jahrestagung der Gesellschaft für Thermische Analyse e.V. (GEFTA 2003) CY - Augsburg, Germany DA - 15.09.2003 PY - 2003 AN - OPUS4-4746 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bücker, Michael A1 - Böcker, Wolfgang D. G. A1 - Reinsch, Stefan A1 - Unger, Brita ED - Acker, J. V. T1 - Wood Modification by Sol-Gel Derived Precursors T2 - 1st European Conference on Wood Modification ; 1st ECWM 2003 CY - Ghent, Belgium DA - 2003-04-03 KW - Silica-sol treatment KW - Wood-inorganic composite KW - Water repellency KW - Environmental stability PY - 2003 SN - 90-806565-2-6 SN - 1018-5593 SP - 255 EP - 259 PB - Univ., Laboratory of Wood Technology CY - Ghent AN - OPUS4-2521 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Herstellung von Gläsern mittlerer Wassergehalte T2 - 79. Glastechnische Tagung CY - Würzburg, Germany DA - 2005-05-23 PY - 2005 AN - OPUS4-7805 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Böcker, Wolfgang D. G. A1 - Bücker, Michael A1 - Reinsch, Stefan A1 - Unger, Brita T1 - Abschlussbericht zum Vorhaben Verbundwerkstoff - Mineralisiertes Holz - FKZ: 033 9829 - Förderschwerpunkt "Integrierter Umweltschutz im Bereich der Holzwirtschaft" des Bundesministeriums für Bildung, Wissenschaft, Forschung und Technologie, BMBF - Projektlaufzeit: 1.10.2000-30.9.2003 KW - Mineralisiertes Holz KW - Sol-Gel KW - Holz KW - Vakuumtränkung KW - Holzschutz KW - Biozide PY - 2004 SP - 1 EP - 94 CY - Berlin AN - OPUS4-12055 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Development of wood-inorganic composites with enhanced properties and environmental stability T2 - 4th International Wood and Natural Fibre Composites Symposium CY - Kassel, Germany DA - 2002-04-10 PY - 2002 AN - OPUS4-12336 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Glastransformationstemperatur wasserhaltiger Gläser T2 - 80. Glastechnische Tagung CY - Dresden, Germany DA - 2006-06-12 PY - 2006 AN - OPUS4-12485 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Thiel, A. A1 - Eberstein, Markus A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Deubener, J. A1 - Schiller, Wolfgang Arno T1 - Viskosität von sinternden Glas/Kristallphasen-Kompositen T2 - 80. Glastechnische Tagung CY - Dresden, Deutschland DA - 2006-06-12 PY - 2006 SN - 3-921089-46-8 SP - 1(?) EP - 3(?) PB - Verl. d. Dt. Glastechn. Ges. CY - Offenbach AN - OPUS4-14045 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dreßler, Martin A1 - Nofz, Marianne A1 - Malz, Frank A1 - Pauli, Jutta A1 - Jäger, Christian A1 - Reinsch, Stefan A1 - Scholz, G. T1 - Aluminum speciation and thermal evolution of aluminas resulting from modified Yoldas sols N2 - Aluminas resulting from sols prepared via a modified Yoldas procedure were studied with differential thermal analysis (DTA), differential thermal gravimetrie (DTG), 27Al nuclear magnetic resonance (27Al MAS NMR) and X-ray diffraction (XRD) concerning their thermal properties, aluminum speciation and phase content. Hydrolysis of aluminum-sec-butoxide in aluminum nitrate solutions allowed to prepare stable sols with varying NO3-/Al molar ratios, solids contents and pH values. Resulting sols contained different aluminum species including also Al13 polycations. Sol preparation conditions also determined aluminum speciation in solid products obtained after thermal treatments of gels obtained from these sols. Al13 polycations and AlO5 species were found to play an important role for thermally induced transformation from amorphous products via eta-Al2O3 to alpha-Al2O3. Intermediately formed eta-Al2O3 promotes the phase transformation to alpha-Al2O3. KW - Alumina KW - Modified Yoldas sols KW - 27Al nuclear magnetic resonance KW - Differential thermal analysis KW - X-ray diffraction PY - 2007 DO - https://doi.org/10.1016/j.jssc.2007.06.018 SN - 0022-4596 SN - 1095-726X VL - 180 IS - 9 SP - 2409 EP - 2419 PB - Elsevier CY - San Diego, Calif. AN - OPUS4-16189 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Brita A1 - Bücker, Michael A1 - Reinsch, Stefan A1 - Hübert, Thomas T1 - Chemical aspects of wood modification by sol-gel-derived silica N2 - It has been shown that tetraethoxysilane-derived precursors are suitable solutions for impregnating pine sapwood to improve its dimensional stability. Tailored sol–gel syntheses result in precursors with nano-scaled silica species which are able to penetrate into the cell walls of wood. The physical fixation of those species inside the cell walls was verified by ESEM/EDX investigations. There is evidence that the silica species are chemically bonded to wood components. Nonreacted alkoxy groups can exist in the wood composites after impregnation. The amount of these organic residues depends on the composition of the precursors, especially their condensation degree and reactivity. Treatments for finishing the composites after the impregnation step to get clean products and stable properties are discussed in this context. An explanation of the complex relationship between solids content in the impregnation solutions and percentage weight gain and bulking of the composites is given. It can be demonstrated that high WPG values (>20 %) are pre-conditions for an effective protection of the resulting composites but they only guarantee efficient improvements if connected with the incorporation of the inorganic component inside the cell walls. Therefore, the sol–gel syntheses have to be carried out in such a manner that very small (<2 nm) as well as reactive species are sufficiently available. This demands syntheses using sub-stoichiometric water contents (H2O/TEOS <4, better <2). KW - Silica-wood composites KW - Sol-gel derived precursors KW - Curing KW - Fixation of silica KW - Dimensional stability PY - 2013 DO - https://doi.org/10.1007/s00226-012-0486-7 SN - 0043-7719 SN - 1432-5225 VL - 47 IS - 1 SP - 83 EP - 104 PB - Springer CY - Berlin AN - OPUS4-26258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Müller, Ralf A1 - Reinsch, Stefan ED - Bansal, N. P. ED - Boccaccini, A.R. T1 - Viscous-phase silicate processing KW - Viskoses Sintern KW - Oberflächenkeimbildung KW - Glaspulver KW - Sintermodelle KW - Sinterglaskeramik KW - Glasmatrixkomposit PY - 2012 SN - 978-0-470-55344-2 IS - Chapter 3 SP - 75 EP - 144 PB - Wiley AN - OPUS4-27054 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Effects of milling on sinter-crystallization of alkaline earth silicate glass powders T2 - 23rd International Congress on Glass, ICG Prague 2013 CY - Prague, Czech Republic DA - 2013-07-01 PY - 2013 AN - OPUS4-28877 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Processing and sinter-crystallization of alkaline earth silicate glass powders T2 - 11th ESG Conference CY - Maastricht, Netherlands DA - 2012-06-03 PY - 2012 AN - OPUS4-27417 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Böcker, Wolfgang D. G. A1 - Bücker, Michael A1 - Reinsch, Stefan A1 - Unger, Brita A1 - Britz, Roswitha T1 - Mineralisiertes Holz - Verbundwerkstoff mit verbesserten Eigenschaften PY - 2001 CY - München AN - OPUS4-1197 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bücker, Michael A1 - Böcker, Wolfgang D. G. A1 - Reinsch, Stefan A1 - Unger, Brita ED - Wielage, B. ED - Leonhardt, G. T1 - Entwicklung umweltverträglicher Holzverbundwerkstoffe mit verbesserter biologischer und Feuchtebeständigkeit T2 - Tagung "Verbundwerkstoffe und Werkstoffverbunde" CY - Chemnitz, Deutschland DA - 2001-09-05 PY - 2001 SN - 3-527-30319-7 SP - 463 EP - 467 PB - Wiley-VCH CY - Weinheim AN - OPUS4-1160 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böcker, Wolfgang D. G. A1 - Bücker, Michael A1 - Reinsch, Stefan A1 - Unger, Brita T1 - Holzverbundwerkstoffe mit verbesserten Eigenschaften N2 - Die offenporige Struktur des Holzes und dessen chemische Zusammensetzung bieten sich an, über Tränkverfahren geeignete Precursoren so an den inneren Oberflächen des Holzes zu fixieren, dass bei anschließender thermischer Behandlung ein umweltfreundlicher anorganisch-organischer Verbundwerkstoff entsteht. Aus der Literatur sind hierzu verschiedene Ansätze bekannt. - Ziel der vorliegenden Arbeit sind Verbesserungen der biologischen Beständigkeit, der Feuchtebeständigkeit unter Beibehaltung bzw. leichter Verbesserung der mechanischen Eigenschaften des Holzes. Dies wird durch eine chemische Verbindung (Haftung) zwischen den verbundbildenden Phasen Holz und Precursor und eventuell zusätzlichen Einbau von funktionellen organischen Gruppen realisiert. Als Precursoren dienen über den Sol-Gel Weg hergestellte Kieselsole, die nach vollständiger thermischer Umsetzung zu rein anorganischen Phasen (SiO2) führen. Die Sol-Gel Synthese konnte so optimiert werden, dass durch die Behandlung eine homogene Beschichtung aller Oberflächen erreicht werden kann. T2 - Integrierter Umweltschutz im Bereich der Holzwirtschaft CY - Göttingen, Deutschland DA - 2002-01-22 PY - 2002 SP - 100 EP - 102 PB - DGfH CY - München AN - OPUS4-1366 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Chládek, Jirí A1 - Müller, Ralf A1 - Weh, Lothar A1 - Reinsch, Stefan T1 - Surface Crystallisation Patterns Caused by Vickers Indentation T2 - Proceedings of workshop 2002 ; 10th Annual University-wide Seminar Workshop 2002 CY - Prague, Czech Republic DA - 2002-02-11 PY - 2002 SN - 80-01-02511-X VL - 6A SP - 610 EP - 611 PB - Czech Technical University CY - Prague AN - OPUS4-1870 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan A1 - Chládek, Jirí A1 - Müller, Ralf A1 - Weh, Lothar T1 - Viskoses Fließen und Oberflächenkristallisation an Vickerseindrücken T2 - 76. Glastechnische Tagung CY - Bad Soden, Deutschland DA - 2002-05-27 PY - 2002 SP - 250 EP - 253 PB - DGG, Deutsche Glastechnische Gesellschaft e.V. CY - Frankfurt/M. AN - OPUS4-1872 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Busch, R. A1 - Tielemann, Christopher A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Patzig, C. A1 - Krause, M. A1 - Höche, T. T1 - Sample preparation for analytical scanning electron microscopy using initial notch sectioning N2 - A novel method for broad ion beam based sample sectioning using the concept of initial notches is presented. An adapted sample geometry is utilized in order to create terraces with a well-define d step in erosion depth from the surface. The method consists of milling a notch into the surface, followed by glancing-angle ion beam erosion, which leads to preferential erosion at the notch due to increased local surface elevation. The process of terrace formation can be utilized in sample preparation for analytical scanning electron microscopy in order to get efficient access to the depth-dependent microstructure of a material. It is demonstrated that the method can be applied to both conducting and non-conducting specimens. Furthermore, experimental parameters influencing the preparation success are determined. Finally, as a proof-of-concept, an electron backscatter diffraction study on a surface crystallized diopside glass ceramic is performed, where the method is used to analyze orientation dependent crystal growth phenomena occurring during growth of surface crystals into the bulk. KW - 3D etching KW - Ion beam erosion Sectioning KW - EBSD KW - Sample preparation KW - Analytical scanning electron microscopy KW - SEM KW - Glass Ceramic KW - Glass KW - Diopsid PY - 2021 DO - https://doi.org/10.1016/j.micron.2021.103090 SN - 0968-4328 VL - 150 PB - Elsevier B.V. AN - OPUS4-53075 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Oriented Surface Crystallization in Glasses N2 - Up to now, oriented surface crystallization phenomena are discussed controversially, and related studies are restricted to few glasses. For silicate glasses we found a good correlation between the calculated surface energy of crystal faces and oriented surface nucleation. Surface energies were estimated assuming that crystal surfaces resemble minimum energy crack paths along the given crystal plane. This concept was successfully applied at the Institute of Physics of Rennes in calculating fracture surface energies of glasses. Several oriented nucleation phenomena can be herby explained assuming that high energy crystal surfaces tend to be wetted by the melt. This would minimize the total interfacial energy of the nucleus. Furthermore, we will discuss the evolution of the microstructure and its effect on the preferred crystal orientation. T2 - ACerS GOMD 2024- Glass & Optical Materials Division Meeting CY - Las Vegas, NV, USA DA - 19.05.2024 KW - Surface nucleation KW - Oriented surface crystallization KW - Surface energy PY - 2024 AN - OPUS4-60238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - A new robot-assisted compositional screening method N2 - The system Na2O.B2O3-SiO2 (NBS) is the basis of many industrial glass applications and therefore one of the most studied systems at all. Glass formation is possible over a wide compositional range, but the system also contains ranges of pronounced phase separation and crystallization tendency. Despite its importance, experimental data are limited to few compositional areas. The general understanding and modelling of glass formation, phase separation, and crystallization in this system would therefore be easier if small step melt series could be studied. The efficient melting of such glass series is now possible with the new robotic glass melting system at the Federal Institute for Materials Research and Testing (BAM, Division Glasses). Using three exemplary joins within this NBS system, the small step changes of glass transition temperature (Tg), crystallization behavior as well as glass density (Roh) was studied. Additionally, experimental Tg and Roh data were compared with their modeled counterparts using SciGlass and a newly developed DFT model, respectively. T2 - Annual meeting of the French Union for Science and Glass Technology (USTV) and the 96th Annual Meeting of the German Society of Glass Technology - USTV-DGG joint meeting. CY - Orléans, France DA - 22.05.2023 KW - Robot-assisted galss melting KW - Sodiumborosilicate glasses KW - Density KW - Glass transformation temperature KW - Property simulation PY - 2023 AN - OPUS4-58724 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Oriented Surface Crystallization in Glasses N2 - Up to now, oriented surface crystallization phenomena are discussed controversially, and related studies are restricted to few glasses. For silicate glasses we found a good correlation between the calculated surface energy of crystal faces and oriented surface nucleation. Surface energies were estimated assuming that crystal surfaces resemble minimum energy crack paths along the given crystal plane. This concept was successfully applied at the Institute of Physics of Rennes in calculating fracture surface energies of glasses. Several oriented nucleation phenomena can be herby explained assuming that high energy crystal surfaces tend to be wetted by the melt. This would minimize the total interfacial energy of the nucleus. Furthermore, we will discuss the evolution of the microstructure and its effect on the preferred crystal orientation. T2 - 13th International Symposium on Crystallization in Glasses and Liquids CY - Orléans, France DA - 24.09.2024 KW - Surface crystallization KW - Surface energy KW - Crystal orientation KW - Silicate glass PY - 2024 AN - OPUS4-62219 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Sub-Tg relaxation in hydrous soda-lime-silicate and sodium-borosilicate glasses N2 - Water plays an important role for the depolymerization of silicate glasses which becomes noticeable by a distinct decrease of glass transformation temperature, Tg. Thus, it has a considerable influence on aging and fatigue as well as on sub-critical crack growth in glasses. In this connection also sub-Tg relaxation processes play a major role, but they are poorly investigated in glasses with high contents of structural bonded water. Therefore, soda-lime-silicate and sodium-borosilicate glasses with water contents up to 5 wt.% H2O were investigated by differential thermal analysis and sphere penetration viscometry, as well as internal friction measurements. The latter was applied to study network related relaxation mechanisms (α-relaxation) in the range of glass transition, as well as faster relaxation modes occurring at lower temperatures (β-, γ- relaxation). Total water content and concentrations of H2O molecules (CH2O) and OH groups (COH) in the glasses were determined by infrared spectroscopy. For low water contents two sub-Tg internal friction peaks were observed and assigned to the low-temperature motion of alkali ions (γ-relaxation) and cooperative movements of dissimilar mobile species under participation of OH at higher temperature (βOH relaxation). For large water contents, where significant amounts of molecular water are evident, a low temperature shoulder appears on the β-relaxation peak. This emerging relaxation mode (βH2O relaxation) was assigned to the motions of H2O molecules. T2 - 91. Glastechnische Tagung CY - Weimar, Germany DA - 28.05.2017 KW - Water-bearing glasses KW - Mechanical loss spectroscopy KW - Relaxation PY - 2017 AN - OPUS4-40810 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Sub-Tg Relaxation in wasserhaltigen Kalk-Natron-Silikat und Natrium-Borosilikat-Gläsern N2 - Wasser hat einen starken Einfluss auf die Depolymerisation des Glasnetzwerks silikatischer Gläser, was sich durch eine deutliche Senkung der Glasübergangstemperatur, Tg, bemerkbar macht. So hat Wasser einen großen Einfluss auf die Alterung, Ermüdung und das unterkritische Risswachstum in Gläsern. Sub-Tg Relaxationsphänomene spielen hier ebenfalls eine große Rolle, sind aber für Gläser mit hohen Gehalten an strukturell gebundenem Wasser kaum untersucht. In dieser Arbeit wurden daher Kalk-Natron-Silikat (NCS) und Natrium-Borosilikat (NBS) Gläser mit Wassergehalten von bis zu 8 Gew.% mittels Differentialthermoanalyse (DTA), Mikropenetration und vor allem dynamisch mechanischer Thermoanalyse (DMTA) zur Charakterisierung netzwerkbedingter Relaxationsmechanismen (alpha-Relaxation) im Bereich des Glasübergangs sowie weiterer schnellerer sub-Tg Relaxationsmechanismen (beta-, gamma-Relaxation) bei tieferen Temperaturen untersucht. Mit Hilfe der IR-Spektroskopie wurde der Gesamtwassergehalt und die Speziation des Wassers als molekulares Wasser oder als OH-Gruppe in den Gläsern bestimmt. Für niedrige Wassergehalte treten zwei sub-Tg Verlustpeaks auf, die der Bewegung von Alkali bei tiefen Temperaturen (gamma-Relaxation) und einer kooperativen Bewegung verschiedener mobiler Spezies unter Beteiligung von OH bei höherer Temperatur (betaOH- Relaxation) zugeordnet werden können. Bei hohen Wassergehalten, bei denen ein messbarer Anteil an molekularem Wasser im Glas vorliegt, ist ein weiterer Verlustpeak zu beobachten, der mit der Bewegung von molekularem Wasser im Glasnetzwerk in Verbindung gebracht werden könnte (betaH2O-Relaxation). T2 - Fachausschuss I der Deutschen Glastechnischen Gesellschaft (DGG) CY - Erlangen, Germany DA - 26.09.2017 KW - Glas KW - Sub-Tg-Relaxation KW - Wasserspeziation KW - Dynamisch mechanischer Thermoanalyse PY - 2017 AN - OPUS4-43307 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wisniewski, W. A1 - Thieme, C. A1 - Müller, Ralf A1 - Reinsch, Stefan A1 - Groß-Barsnick, S.-M. A1 - Rüssel, C. T1 - Oriented surface nucleation and crystal growth in a 18BaO·22CaO·60SiO2 mol% glass used for SOFC seals N2 - A glass of the composition 37BaO·16CaO·47SiO2 wt% produced on an industrial scale is crystallized at 970 °C for times ranging from 15 min to 2 h. The crystallization at the immediate surface as well as the crystal growth into the bulk are analyzed using scanning electron microscopy (SEM) including energy dispersive X-ray spectroscopy (EDXS) and electron backscatter diffraction (EBSD) as well as X-ray diffraction in the Θ–2Θ setup (XRD). The immediate surface shows the oriented nucleation of walstromite as well as the formation of wollastonite and an unknown phase of the composition BaCaSi3O8. All three phases also grow into the bulk where walstromite ultimately dominates the kinetic selection and grows throughout the bulk due to a lack of bulk nucleation. Walstromite shows systematic orientation changes as well as twinning during growth. A critical analysis of the XRD-patterns acquired from various crystallized samples indicates that their evaluation is problematic and that phases detected by XRD in this system should be verified by another method such as EDXS. KW - Glass KW - Surface nucleation KW - Orientation KW - EBSD PY - 2018 DO - https://doi.org/10.1039/c7ce02008b VL - 20 IS - 6 SP - 787 EP - 795 PB - Royal Society of Chemistry AN - OPUS4-44405 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Behrens, H. A1 - Bauer, U. A1 - Reinsch, Stefan A1 - Kiefer, P. A1 - Müller, Ralf A1 - Deubener, J. T1 - Structural relaxation mechanisms in hydrous sodium borosilicate glasses N2 - Borosilicate glasses (16Na2O–10B2O3–74SiO2, NBS) with water contents up to 22 mol% H2O were prepared to study the effect of water on structural relaxation using DTA, viscometry and internal friction measurements. The results show that the glass transition temperature Tg of DTA and the isokom temperature T12, of viscometry are in excellent agreement, confirming the equivalence of enthalpy and viscous relaxation for NBS glass. Combining Tg data with water speciation data demonstrates that OH groups are mainly responsible for the decrease of Tg with increasing hydration, while molecular water plays only a minor role. Internal friction spectra at 7.125 Hz confirm the decisive influence of water on mechanical relaxation. The temperature range of α-relaxation (glass transition) strongly decreases while two β-relaxation peaks (sub-Tg) progressively appear with increasing water content. A high temperature β-relaxation peak, attributed to the presence of OH groups, shifts from 670 to 450 K as total water content increases from 0.01 to 5 wt%. A low temperature β-relaxation peak, attributed to molecular water, appears at 380 K and 330 K in glasses containing 3 and 5 wt% H2O, respectively. These findings suggest that relaxation mechanism of different hydrous species at low temperature may contribute to fatigue of stressed glasses. KW - Borosilicate glass KW - Water KW - Relaxation KW - Internal friction KW - Glass transition PY - 2018 DO - https://doi.org/10.1016/j.jnoncrysol.2018.05.025 VL - 497 SP - 30 EP - 39 PB - Elsevier B.V. AN - OPUS4-45608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Orientierte Oberflächenkristallisation in Gläsern N2 - Bislang wird das Phänomen der orientierten Oberflächenkristallisation kontrovers diskutiert und entsprechende Studien beschränken sich auf nur wenige Gläser. Für Silikatgläser haben wir eine gute Korrelation zwischen der berechneten Oberflächenenergie von Kristallflächen und der orientierten Oberflächenkeimbildung gefunden. Die Oberflächenenergien wurden unter der Annahme abgeschätzt, dass die Kristalloberflächen bei der Keimbildung den Kristallebenen mit minimaler Energie entsprechen, denen ein Riss beim Bruch folgt. Dieses Konzept wurde am Institut für Physik in Rennes erfolgreich bei der Berechnung der Bruchflächenenergien von Gläsern angewandt. Mehrere orientierte Keimbildungsphänomene lassen sich dadurch erklären, dass man annimmt, dass Kristalloberflächen mit hoher Energie dazu neigen, von der Schmelze benetzt zu werden. Dies minimiert die gesamte Grenzflächenenergie des Keims. Darüber hinaus werden wir die Entwicklung der Mikrostruktur beim weiteren Kristallwachstum und ihre Auswirkungen auf die bevorzugte Kristallorientierung diskutieren. T2 - 21. Treffen des DGG-DKG Arbeitskreises „Glasig-kristalline Multifunktionswerkstoffe“ CY - Mainz, Germany DA - 22.02.2024 KW - Oberflächenkeimbildung KW - Kristallorientierung KW - Grenzflächenenergie PY - 2024 AN - OPUS4-60237 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Robot-assisted compositional screening in the System Na2O-Al2O3-B2O3-SiO2 N2 - The system Na2OB2O3SiO2 (NBS) is the basis of many industrial glass applications and therefore one of the most studied systems at all. Glass formation is possible over a wide compositional range, but the system also contains ranges of pronounced phase separation and crystallization tendency. Even small addition of Al2O3can change this behavior essentially. As the Na2OAl2O3B2O3SiO2 (NABS) system is also known as the basis for glasses in strength-relevant applications, the behavior during the transition from the NBS system to the NABS system is of interest. Therefore, some small step melt series in these systems were studied using the robotic glass melting system at the Federal Institute for Materials Research and Testing (BAM, Division Glasses). For these series the small step changes of glass transition temperature, crystallization behavior as well as glass density were studied. Additionally, experimental data were compared with their modeled counterparts. T2 - 98. Glastechnische Tagung CY - Goslar, Germany DA - 26.05.2025 KW - Sodium alumino boro silicate glasses KW - Glass transition temperature KW - Density KW - Robotic melting PY - 2025 AN - OPUS4-64076 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Paskin, Alice A1 - Couasnon, Thaïs A1 - Blukis, Roberts A1 - Perez, Jeffrey Paulo H. A1 - Reinsch, Stefan A1 - Roddatis, Vladimir A1 - Syczewski, Marcin A1 - Benning, Liane G. T1 - Temperature-Induced Phase Transitions of Vivianite: In Situ Analysis of a Redox-Driven Crystallization N2 - We document a solid-state, temperature-dependent (25−700 °C), multistage redox transformation of crystalline ferrous iron phosphate, vivianite (Fe3(PO4)2·8H2O). Under anoxic conditions, vivianite breaks down at T > 250 °C into an anhydrous, amorphous intermediate Fe3(PO4)2 phase, yet the bulk shape and morphology of the starting vivianite crystals were retained. This amorphous intermediate phase remained stable until T > 500 °C, after which a redox-dependent crystallization into two different minerals was observed. Under anoxic conditions, the amorphous ferrous intermediate (Fe3(PO4)2) transformed into the crystalline ferrous phosphate (graftonite, (Fe2+)3(PO4)2), while under oxic conditions it crystallized into a ferric phosphate (rodolicoite, Fe3+PO4). Graftonite formation occurs via an exothermic molar enthalpy (ΔHcryst) of −16.7 ± 0.2 kJ mol−1. Rietveld refinements of the two crystalline endmembers (vivianite and graftonite) revealed a unit cell volume decrease of ∼3.1% during the transformation, which was observed by in situ electron microscopic observations as an overall shrinking of the initial vivianite crystals. Despite volume loss and bubble-like features, the original vivianite shape was preserved, indicating a solid-state pseudomorphic transformation. Ex situ XRD and TEM-EELS analyses confirmed the ferrous-to-ferric oxidation, forming rodolicoite, through changes in the Fe geometry and oxidation state. KW - Vivianite KW - Graftonite KW - Crystallization enthalpy KW - Ferrous phosphates PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640782 DO - https://doi.org/10.1021/acs.inorgchem.5c02399 SN - 0020-1669 VL - 46 IS - 36 SP - 18227 EP - 18236 PB - American Chemical Society (ACS) AN - OPUS4-64078 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tielemann, Christopher A1 - Busch, R. A1 - Reinsch, Stefan A1 - Patzig, C. A1 - Höche, T. A1 - Avramov, I. A1 - Müller, Ralf T1 - Oriented surface nucleation in diopside glass N2 - Es wird die Texturbildung in kristallisierendem Diopsidglas im Zusammenhang mit der Oberflächenbeschaffenheit der unbehandelten Probe untersucht. Zudem wird der diskutiert, dass es sich bei der Texturbildung in Gläsern höchstwahrscheinlich um ein Nukleationsphänomen handelt welches auf die richtungsabhängige Grenzflächenenergie der kristallisierenden Phase zurückzuführen ist. N2 - Oriented surface crystallization on polished diopside glass surfaces has been studied with scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy and laser scanning microscopy. An orientation preference of [001] parallel to the glass surface was detected for separately growing diopside crystals even as small as 700 nm in size. This finding shows that crystal orientation occurs in the outermost surface layer without crystal-crystal interaction and indicates that the crystal orientation is a result of oriented nucleation. Depending on surface preparation, monomodal crystal orientation distributions with [100] perpendicular to the surface or bimodal distributions with [100] and [010] perpendicular to the glass Surface were detected. It was also shown that the degree of crystal orientation increases with decreasing Surface roughness. The observed orientation of diopside crystals could be explained in terms of the interfacial energies of different crystal faces. KW - Surface energy KW - Glass ceramic KW - Glass KW - EBSD KW - Diopsid PY - 2021 UR - https://www.sciencedirect.com/science/article/pii/S002230932100020X DO - https://doi.org/10.1016/j.jnoncrysol.2021.120661 SN - 0022-3093 VL - 562 PB - Elsevier B.V. AN - OPUS4-53073 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Waurischk, Tina A1 - Reinsch, Stefan A1 - Rouxel, T. A1 - Behrens, H. A1 - Deubener, J. A1 - Müller, Ralf T1 - Vacuum crack growth in alkali silicate glasses N2 - Crack growth velocity in alkali silicate glasses was measured in vacuum across 10 orders of magnitude with double cantilever beam technique. Measured and literature crack growth data were compared with calculated intrinsic fracture toughness data obtained from Young´s moduli and the theoretical fracture surface energy estimated from chemical bond energies. Data analysis reveals significant deviations from this intrinsic brittle fracture behavior. These deviations do not follow simple compositional trends. Two opposing processes may explain this finding: a decrease in the apparent fracture surface energy due to stress-induced chemical changes at the crack tip and its increase due to energy dissipation during fracture. KW - Silicate glass KW - Brittle fracture KW - Crack growth KW - Calculated intrinsic fracture toughness PY - 2021 DO - https://doi.org/10.1016/j.jnoncrysol.2021.121094 SN - 0022-3093 VL - 572 SP - 1 EP - 8 PB - Elsevier CY - Amsterdam AN - OPUS4-53144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Surface-Initiated Microstructure Formation in Glass Ceramics N2 - Up to now, oriented surface crystallization phenomena are discussed controversially, and related studies are restricted to few glasses. For silicate glasses we found a good correlation between the calculated surface energy of crystal faces and oriented surface nucleation. Surface energies were estimated assuming that crystal surfaces resemble minimum energy crack paths along the given crystal plane. This concept was successfully applied by Rouxel in calculating fracture surface energies of glasses. Several oriented nucleation phenomena can be herby explained assuming that high energy crystal surfaces tend to be wetted by the melt. This would minimize the total interfacial energy of the nucleus. Furthermore, we will discuss the evolution of the microstructure and its effect on the preferred crystal orientation. T2 - 26th International Congress on Glass CY - Berlin, Germany DA - 03.07.2022 KW - Glass KW - Oriented surface crystallization KW - Surface energy KW - Bond energy KW - Nucleation mode PY - 2022 AN - OPUS4-56070 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waurischk, Tina A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Chen, Y.-F. A1 - Contreras Jaimes, A. T1 - Datengetriebener Workflow für die beschleunigte Entwicklung von Glas (GlasDigital) N2 - Das Projekt GlasDigital wurde im allgemeinen vorgestellt, sowie die einzelnen Zwischenstände der verschiedenen Arbeitspakete aller Projektpartner präsentiert. Die allgemeine Porjektvorstellung ist auf deutsch. Die Zwischenstände der Arbeitsinhalte sind auf englisch. T2 - PMD Vollversammlung CY - Berlin, Germany DA - 03.11.2022 KW - Oxidglas KW - Robotische Glasschmelzanlage KW - ML KW - Ontologie KW - Digitaler Zwilling KW - Bildanalyse PY - 2022 AN - OPUS4-56491 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Ralf A1 - Weh, Lothar A1 - Reinsch, Stefan T1 - Oberflächenprofile partiell kristallisierter Silikatgläser T2 - 73. Glastechnische Tagung CY - Halle (Saale), Deutschland DA - 1999-05-31 KW - Kristallisation KW - Silikatgläser PY - 1999 SP - 26 EP - 29 CY - Frankfurt/Main AN - OPUS4-819 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agea Blanco, Boris A1 - Blaess, C. A1 - Reinsch, Stefan A1 - Brauer, D. A1 - Müller, Ralf T1 - Sintering and foaming of barium and calcium silicate glass powders N2 - Sintering and foaming of barium and calcium silicate glass powder compacts have been studied for different powder milling. Sintering was measured by means of heating microscopy backed up by XRD, DTA, Vacuum Hot Extraction (VHE) and electron microscopy. Foaming intensity strongly increased with decreasing glass partiefe size. Although powder compacts were uniaxially pressed and sintered in ambient air, foaming was affected by the milling atmosphere and most intensive for milfing in C02. Conformingly, VHE studies revealed that foaming of fully sintered samples was mainly driven by C02, even for powders milled in technical air, Ar and N2. Prolonged storage of air milled barium silicate glass powders in ambient air before pressing and sintering caused further increase of foaming intensity. These findings indicate that carbonaceous species are preferentially trapped to or close beneath the powder surface during milling and later storage. The temperature range of C02 degassing from fully sintered barium and calcium silicate g/ass powder compacts fits the temperature ranges of decomposition of BaC03 and CaC03 mix-milled with the respective barium and calcium silicate glass powders. T2 - IMAPS/ACerS 11th International CICMT conference and exhibition CY - Dresden, Germany DA - 20.04.2015 KW - Sintering KW - Foaming KW - Silicate glass powders KW - Barium and calcium silicate plass powders KW - Degassing PY - 2015 SN - 978-1510804562 SP - 31 EP - 37 AN - OPUS4-35250 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reinsch, Stefan A1 - Rössler, C. A1 - Bauer, Ute A1 - Müller, Ralf A1 - Deubener, J. A1 - Behrens, H. T1 - Water, the other network modifier in borate glasses N2 - In the present study we have investigated whether the effect of water on properties of borate glasses resembles that of alkali oxide. Soda-lime-borate glasses with nominal compositions of x Na2O, 10 CaO, (90-x) B2O3 (x = 5, 15 and 25 mol%) were doped with up to 8 wt.% H2O by processing glass powder + distilled water in platinum capsules in an internally heated gas pressure vessel at 1523 K and 500 MPa. The water content of hydrous glasses was determined by Karl-Fischer titration and near-infrared spectroscopy. The glass transition temperature T-g. was derived from DTA and micropenetration experiments for which the effect of water loss at the surface of the hydrous glasses was studied. Heating glass samples at 10 K min(-1) in the DTA resulted in T-g values which are close to T-12 isokom temperatures confirming the equivalence of enthalpy relaxation and viscous relaxation for borate glasses. For all three glass series it is shown that T-g strongly decreases whereas the liquid fragility strongly increases upon the addition of water. These findings reveal that H2O primarily causes breaking of B-O-B bonds rather than supporting 4-fold coordinated boron as it is well-known for alkali oxides in this concentration range. (C) 2015 Elsevier B.V. All rights reserved. KW - Wasserhaltige Gläser KW - Viskosität KW - Boratgläser KW - Thermische Analyse KW - Viscosity KW - Borate glasses KW - Thermal analysis KW - Water-bearing glasses PY - 2016 DO - https://doi.org/10.1016/j.jnoncrysol.2015.10.010 SN - 0022-3093 VL - 432 SP - 208 EP - 217 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-35123 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan A1 - Eberstein, Markus A1 - Müller, Ralf A1 - Schiller, Wolfgang Arno A1 - Schweiger, M. T1 - Lastabhängige Schwindung von Glaspulvern N2 - Glasig-kristalline Sinterwerkstoffe werden für vielfältige Anwendungen eingesetzt. Bei einem hohen Glasanteil ist ein Einfluss geringer Lasten auf das Schwindungsverhalten möglich, so dass es zu Fehlinterpretationen des Schwindungsverhaltens bei gebräuchlichen Horizontaldilatometer kommen kann. T2 - 75. Glasetechnische Tagung CY - Wernigerode, Germany DA - 21.05.2001 KW - Glasig-kristalline Sinterwerkstoffe KW - Schwindungsverhalten KW - Horizontaldilatometer PY - 2001 AN - OPUS4-35786 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Agea Blanco, Boris A1 - Reinsch, Stefan A1 - Müller, Ralf T1 - Sintering and foaming of barium silicate glass powder compacts N2 - The manufacture of sintered glasses and glass-ceramics, glass matrix composites, and glass-bounded ceramics or pastes is often affected by gas bubble formation. Against this background, we studied sintering and foaming of barium silicate glass powders used as SOFC sealants using different powder milling procedures. Sintering was measured by means of heating microscopy backed up by XPD, differential thermal analysis, vacuum hot extraction (VHE), and optical and electron microscopy. Foaming increased significantly as milling progressed. For moderately milled glass powders, subsequent storage in air could also promote foaming. Although the powder compacts were uniaxially pressed and sintered in air, the milling atmosphere significantly affected foaming. The strength of this effect increased in the order Ar ≈ N2 < air < CO2. Conformingly, VHE studies revealed that the pores of foamed samples predominantly encapsulated CO2, even for powders milled in Ar and N2. Results of this study thus indicate that foaming is caused by carbonaceous species trapped on the glass powder surface. Foaming could be substantially reduced by milling in water and 10 wt% HCl. KW - Glass powder KW - Sintering KW - Foaming KW - SOFC PY - 2016 UR - http://journal.frontiersin.org/article/10.3389/fmats.2016.00045/full?&utm_source=Email_to_authors_&utm_medium=Email&utm_content=T1_11.5e1_author&utm_campaign=Email_publication&field=&journalName=Frontiers_in_Materials&id=214488 DO - https://doi.org/10.3389/fmats.2016.00045 SN - 2296-8016 VL - 3 SP - Article 45, 1 EP - 10 AN - OPUS4-38303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Glass transition and viscosity of hydrous soda-lime-borate glasses N2 - Boron oxide glasses usually show low glass transition temperature Tg due to the three-fold oxygen coordination of boron. Adding of alkali and alkaline earth oxides to the glass composition will not decrease but increase Tg due to a change in boron coordination from trigonal to tetrahedral, known as the boron anomaly. Only for higher fractions of alkali oxides, non-bridging oxygens (NBO) are progressively formed in competition with tetrahedrally coordinated boron, which leads to a decrease in viscosity. ln contrast to this well-known behavior of alkali oxides (R2O), there is little known about adding H2O to borate glasses. The present work therefore aims in shedding light on the rheological properties of hydrous soda lime borate glasses with particular focus on the role of water. For doing so, we determined Tg as a function of Na2O and H2O content using differential thermal analysis (DTA) backed up by micropenetration viscosity measurements. Results show that water decreases Tg for all glasses and water concentrations under study (< 8 wt.% total water). Obviously, water mostly causes the formation of NBO having no significant influence on boron coordination as seen for alkaline. T2 - Crystallization 2015 CY - Shanghai, China DA - 07.04.2016 KW - Borate glasses KW - Thermal analyses KW - Viscosity KW - Water-bearing glasses PY - 2016 AN - OPUS4-38318 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Waurischk, Tina A1 - Müller, Ralf A1 - Reinsch, Stefan A1 - Kiefer, P. A1 - Deubener, J. A1 - Balzer, R. A1 - Behrens, H. T1 - Crack Growth in Hydrous Soda-Lime Silicate Glass N2 - Stable crack growth was measured for nominal dry and water-bearing (6 wt%) soda-lime silicate glasses in double cantilever beam geometry and combined with DMA studies on the effects of dissolved water on internal friction and glass transition, respectively. In vacuum, a decreased slope of logarithmic crack growth velocity versus stress intensity factor is evident for the hydrous glass in line with an increase of b-relaxation intensity indicating more energy Dissipation during fracture. Further, inert crack growth in hydrous glass is found to be divided into sections of different slope, which indicates different water related crack propagation mechanism. In ambient air, a largely extended region II is observed for the hydrous glass, which indicates that crack growth is more sensitive to ambient water. KW - Internal friction KW - Soda-lime silicate glass KW - Water content KW - Stable crack growth KW - DCB geometry KW - Stress intensity factor PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506829 DO - https://doi.org/10.3389/fmats.2020.00066 VL - 7 SP - Articel 66 AN - OPUS4-50682 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kiefer, P. A1 - Maiwald, M. A1 - Deubener, J. A1 - Balzer, R. A1 - Behrens, H. A1 - Waurischk, Tina A1 - Reinsch, Stefan A1 - Müller, Ralf T1 - Automated Analysis of Slow Crack Growth in Hydrous Soda-Lime Silicate Glasses N2 - To explore the impact of ambient and structural water on static fatigue, the initiation and growth of 3279 Vickers induced median radial cracks were automatically recorded and analyzed. We find that humidity is more efficient in initiating cracks and promoting their growth than water, which is dissolved in the glass structure. In particular for slow crack growth (< 3x10-6 m s-1), tests in dry nitrogen showed a considerable decrease in the crack growth exponent with increasing water content of the glasses. On the other hand, if tests were performed in humid air, the crack growth exponent was independent of the water content of the hydrous glasses, while stress intensity decreased slightly. These observations indicate that water promotes the processes at the crack-tip regardless of its origin. However, ambient water is more efficient. KW - Indentation fracture toughness KW - Slow crack growth KW - Automated analysis KW - Hydrous glass KW - Vickers indentation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-513085 DO - https://doi.org/10.3389/fmats.2020.00268 VL - 7 SP - 268 AN - OPUS4-51308 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Welter, T. A1 - Müller, Ralf A1 - Deubener, J. A1 - Marzok, Ulrich A1 - Reinsch, Stefan T1 - Hydrogen Permeation Through Glass N2 - Physical storage of gaseous hydrogen under high-pressure in glassy micro-containers such as spheres and capillaries is a promising concept for enhancing safety and the volumetric capacity of mobile hydrogen storage systems. As very low permeation through the container wall is required for storage of compressed hydrogen, development of glasses of minimal hydrogen permeability is needed. For this purpose, one has to understand better the dependence of hydrogen permeability on glass structure. The paper points out that minimizing the accessible free volume is as one strategy to minimize hydrogen permeability. Based on previously measured and comprehensive literature data, it is shown that permeation is independently controlled by ionic porosity and network modifier content. Thus, ionic porosity in modified and fully polymerized networks can be decreased equally to the lowest hydrogen permeability among the glasses under study. Applying this concept, a drop of up to 30,000 with respect to the permeation of hydrogen molecules through silica glass is attainable. KW - Ionic porosity KW - hydrogen storage KW - Glass KW - Permeability KW - Solubility KW - Diffusivity PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-513927 DO - https://doi.org/10.3389/fmats.2019.00342 VL - 6 SP - Article 342 AN - OPUS4-51392 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gomes Fernandes, Roger A1 - Al-Mukadam, Raschid A1 - Bornhöft, Hansjörg A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Selle, Susanne A1 - Deubener, Joachim T1 - Viscous Sintering of Acid Leached Glass Powders N2 - The process of viscous flow sintering is a phenomenon that is closely linked to the surface properties of the glass particles. In this work, we studied the extreme case of acid-leaching of soda-lime-silicate glass beads of two different particle size distributions and its effects on non-isothermal viscous sintering of powder compacts. Depth profiling of the chemical composition after leaching revealed a near-surface layer depleted in alkali and alkaline earth ions, associated with concurrent hydration as mass loss was detected by thermogravimetry. Heating microscopy showed that acid treatment of glasses shifted the sinter curves to higher temperatures with increasing leaching time. Modelling of the shrinkage with the cluster model predicted a higher viscosity of the altered surface layer, while analysis of the time scales of mass transport of mobile species (Na+, Ca2+ and H2O) during isochronous sintering revealed that diffusion of Na+ can compensate for concentration gradients before sintering begins. Also, exchanged water species can diffuse out of the altered layer, but the depletion of Ca2+ in the altered surface layer persists during the sinter interval, resulting in a glass with higher viscosity, which causes sintering to slow down. KW - Glass powder KW - Viscous sintering KW - Acid-leaching KW - Sinter retardation PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589008 DO - https://doi.org/10.52825/glass-europe.v1i.681 VL - 1 SP - 37 EP - 53 AN - OPUS4-58900 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reinsch, Stefan A1 - Welter, T. A1 - Müller, Ralf A1 - Deubener, J. T1 - Hydrogen Permeability of Tectosilicate Glasses for Tank Barrier Liners N2 - The permeation of hydrogen gas was studied in meta-aluminous (tectosilicate) glass powders of Li2O×Al2O3×SiO2 (LAS), Na2O×Al2O3×SiO2 (NAS) and MgO×Al2O3×SiO2 (MAS) systems by pressure loading and vacuum extraction in the temperatures range 210–310 °C. With this method, both the solubility S and the diffusivity D were determined, while the permeability was given by the product SD. For all glasses, S was found to decrease with temperature, while D increased. Since the activation energy of diffusion of H2 molecules exceeded that of dissolution, permeation increased slightly with temperature. When extrapolated to standard conditions (25 °C), the permeability of tectosilicate glasses was found to be only 10-22–10-24 mol H2 (m s Pa)-1, which is 8–10 magnitudes lower than most polymers. Thin glass liners of these compositions are expected to be the most effective barrier for tanks of pressurised hydrogen. KW - Hydrogen permeation KW - Aluminosilicate glasses KW - Hydrogen storage tank KW - Glass liner PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-587284 DO - https://doi.org/10.52825/glass-europe.v1i.425 VL - 1 SP - 1 EP - 11 AN - OPUS4-58728 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Ralf A1 - Behrens, Harald A1 - Ageo-Blanco, Boris A1 - Reinsch, Stefan A1 - Wirth, Thomas T1 - Foaming Species and Trapping Mechanisms in Barium Silicate Glass Sealants N2 - Barium silicate glass powders 4 h milled in CO2 and Ar and sintered in air are studied with microscopy, total carbon analysis, differential thermal Analysis (DTA), vacuum hot extraction mass spectroscopy (VHE-MS), Fourier-transformed infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary-ion mass spectrometry (TOF-SIMS). Intensive foaming of powder compacts is evident, and VHE studies prove that foaming is predominantly caused by carbonaceous species for both milling gases. DTA Shows that the decomposition of BaCO3 particles mix-milled with glass powders occurs at similar temperatures as foaming of compacts. However, no carbonate at the glass surface could be detected by FTIR spectroscopy, XPS, and TOF-SIMS after heating to the temperature of sintering. Instead, CO2 molecules unable to rotate identified by FTIR spectroscopy after milling, probably trapped by mechanical dissolution into the glass bulk. Such a mechanism or microencapsulation in cracks and particle aggregates can explain the contribution of Ar to foaming after intense milling in Ar atmosphere. The amount of CO2 molecules and Ar, however, cannot fully explain the extent of foaming. Carbonates mechanically dissolved beneath the surface or encapsulated in cracks and micropores of particle aggregates are therefore probably the major foaming source. KW - Milling KW - Foaming KW - Glass powder KW - Sintering PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531227 DO - https://doi.org/10.1002/adem.202100445 SN - 1438-1656 VL - 24 IS - 6 SP - 2100445-1 EP - 2100445-13 AN - OPUS4-53122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chladek, J. A1 - Müller, Ralf A1 - Weh, Lothar A1 - Reinsch, Stefan T1 - Viscous flow and surface crystallization caused by Vickers indentation PY - 2004 SN - 0927-4472 VL - 77 IS - 1 SP - 1 EP - 6 PB - Elsevier CY - Amsterdam AN - OPUS4-6235 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -