TY - CONF A1 - Spaltmann, Dirk A1 - Kogia, M. A1 - Liedtke, S. A1 - Dykeman, D. A1 - Gradt, Thomas T1 - Challenges for the design of a universal tribological database for materials N2 - Renowned institutions in the field of tribology combine their testing and analytical capabilities with experts in materials/process information management technology to provide the respective services in Europe (i-TRIBOMAT). This requires a centralized materials information management system or the standardised capture, consolidation and harmonization of tribological information. T2 - 60. Tribologie-Fachtagung CY - Göttingen, Germany DA - 23.09.2019 KW - Database KW - Tribology KW - Digital KW - LIMS PY - 2019 AN - OPUS4-49145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Géraldine A1 - Gradt, Thomas T1 - Sliding performance of polymer materials in hydrogen and methane N2 - In this talk, the sliding performance of polymer materials in hydrogen and methane are presented. The influence of the environmental conditions is discussed in terms of material composition, counterface, transfer film formation, and triboreactions. T2 - International Tribology Conference/ITC CY - Sendai, Japan DA - 17.09.2019 KW - Friction KW - Wear KW - Polymer composites KW - Hydrogen KW - Methane PY - 2019 AN - OPUS4-49148 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Langklotz, U. A1 - Babutzka, Martin A1 - Burkert, Andreas A1 - Schneider, M. T1 - FT-IR spectroscopy of corrosion products formed on zinc under atmospheric conditions N2 - Zinc materials are of high importance in the field of corrosion protection. For example, almost half of the annual production of zinc is used as anti-corrosive layer for steel components, particularly under atmospheric conditions. The corrosion protection is frequently ascribed to zinc carbonate species with low solubility which form on the metal surface under atmospheric conditions. Due to the technological importance and wide use of zinc materials, its corrosion behavior and the formation of reaction products has been intensively investigated over decades. Assuming atmospheric corrosion conditions, an initial native passive film of few nanometers thickness forms spontaneously. It consists of zinc oxide and hydroxide, transforming into various species in dependence of the surrounding atmospheric conditions. This study focusses on the investigation of corrosion product layers on massive titanium-zinc sheets, formed during short- and mid-term exposure experiments by Fourier-transformed infrared spectroscopy. This method enables the investigation of extremely thin native passive films which form during the initial hours of exposure. Furthermore, aged surface layers are analyzed which were formed by transformation of initial passive layers over the time of several weeks. The spectroscopic investigations are complemented by scanning electron microscopy (SEM/EDX) in order to obtain information on the chemical composition and morphology of the corrosion products. The combination of both methods offers a comprehensive view on the processes occurring in the early stages of zinc corrosion. T2 - EUROCORR 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Zinc coatings KW - FT-IR KW - Layer formation PY - 2019 AN - OPUS4-49132 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Jan P. A1 - Dell'Avvocato, G. A1 - Krankenhagen, Rainer T1 - Applying a two-layer quadrupole model for quantitative thermography at overload-induced delaminations in GFRP N2 - The applicability of 1D-quadrupole-model on the depth estimation of overload-induced delaminations is tested in this contribution. While classical 1D-methods like Pulsed Phase Transformation and Thermographic Signal Reconstruction determine the depth of a defect by one parameter, a two-layer quadrupole model provides two parameters: depth and thermal resistance. In addition, the convectional losses at the surfaces may be considered. The defect investigated is a large-scale delamination in glass fibre reinforced polymer generated by tension overload. T2 - Advanced Infrared Technology & Applications (AITA) CY - Florenz, Italy DA - 16.9.2019 KW - Aktive Thermographie KW - Nicht-lineare Regression KW - 1D-Simulation KW - GFK PY - 2019 AN - OPUS4-49133 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stephan-Scherb, Christiane T1 - Elucidation of Surface Degradation Phenomena By In Situ X-ray techniques N2 - Presentation of in situ and real time approaches to study high temperature oxidation phenomena by adavnced X-ray techniques. Application to the analysis of degradation mechanisms of chemical complex alloys and high entropy alloys was presented. T2 - SPP 2006 Hot Topic Meeting "Large Scale Facility Based Techniques CY - Helmholtz-Zentrum Berlin für Materialien und Energie, Germany DA - 26.09.2019 KW - High entropy alloys KW - Diffraction KW - In situ KW - Oxidation PY - 2019 AN - OPUS4-49134 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pötzsch, Sina A1 - Bäßler, Ralph A1 - Weltschev, Margit T1 - Resistance of metals exposed to heating oil blends with 10 % and 20 % biodiesel (FAME) N2 - In Europe biodiesel gained from rapeseeds are considered as an alternative to common fossil fuels due to its environmental performance and its independence from import of raw materials. Biodiesel is also suitable to serve as blending component to heating oil. In that case, it must be considered that changes of fuel composition might cause material degradation. The objective of this research was to investigate the resistance of metallic materials exposed to heating oil, heating oil blend B20 with 20 % biodiesel and pure biodiesel. Furthermore, the resistance of metals to eight-year aged B10 and six-year aged pure biodiesel was evaluated. Ageing of biodiesel forms acids and water which might propagate metal corrosion. The investigated metals (aluminium, unalloyed steel, austenitic CrNi-steel, copper, die cast zinc and brass) are commonly used for components in middle distillate facilities. According to DIN 50905-4 the immersed metals were exposed in a climate chamber at 50°C for 4 weeks. The metallic materials were evaluated as resistant if the annual corrosion rate due to uniform corrosion remained under 0.1 mm/year and no localized corrosion in the form of pitting occurred. The corrosion rates of the exposed materials stayed far below the limit of 0.1 mm/year for all tested fuels. An exception was die cast zinc ZP0410 in eight-year aged B10; a corrosion rate up to 0.3 mm/year due to uniform corrosion was measured. In no case localized corrosion occurred. Copper and brass caused discolouration of biodiesel from yellow to green. In conclusion, the tested metallic materials were resistant in heating oil, heating oil blend B20 and pure biodiesel at 50 °C. Even the metals exposed to six-year aged biodiesel and eight-year aged B10 showed no uniform or localized corrosion; except for zinc, which was not resistant in eight-year aged B10. T2 - EUROCORR 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Metals KW - Heating oil KW - Biodiesel KW - RME KW - Corrosion KW - Compatibility KW - FAME PY - 2019 AN - OPUS4-49137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig A1 - Weise, Frank A1 - Oesch, Tyler A1 - Dlugosch, R. A1 - Powierza, Bartosz T1 - Transport and reconfiguration of moisture in HPC due to unilateral heating N2 - Explosive spalling is caused by, among others, the thermohydraulic spalling mechanism. During this process, vaporization, dehydration, moisture-transport and condensation processes interact. As a result, a drying and dehydration zone as well as a saturated zone, known as a moisture clog, are observed inside the unilaterally-heated concrete. The presented research is focused on the experimental investigation of the underlying thermohydraulic processes. To investigate these, a test methodology based on X-ray computed tomography (CT) and nuclear magnetic resonance (NMR) was developed. Thereby, the X-ray CT scans are carried out simultaneously during the application of a defined unilateral-heating regime on a specially-constructed specimen. This miniaturized specimen, equipped with a double-layer casing, reproduces the condition within a planar, unilaterally-heated building component. A preliminary test methodology and the first experimental results were presented at the 5th International Workshop on Concrete Spalling in Borås, Sweden (2017). The contribution for the upcoming workshop presents an improved version of this test methodology and new results for a high-performance concrete (HPC) mixture exposed to temperatures up to 500 °C. Regarding the CT measurements, a higher time-resolution of 15 min was achieved and a quantification of the moisture changes was implemented. Due to an increase in signal quality of the NMR measurements, a pore-size specific moisture distribution can now be resolved. This allows to conclude about the moisture reconfiguration between small gel pores and larger interhydrate pores. Additionally, the NMR measurement are no longer limited to first 2.5 cm below the heated surface but a one-dimensional moisture distribution can now be estimated over the whole 10 cm long specimen. The presented results demonstrate that the combination of X-ray CT and NMR measurements enables to image and quantify the thermally-induced moisture transport and reconfiguration from small gel pores up to macro pores. This provides important insights into the thermohydraulic damage mechanism and leads to a better understanding of spalling avoidance strategies, like the addition of polypropylene fibres. T2 - 6th International Workshop on Concrete Spalling due to fire exposure CY - Sheffield, UK DA - 19.09.2019 KW - Moisture clog KW - X-ray CT KW - NMR KW - Moisture transport KW - HPC PY - 2019 AN - OPUS4-49159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zocca, Andrea A1 - Mühler, T. A1 - Lima, P. A1 - Günster, Jens A1 - Lüchtenborg, Jörg T1 - Advanced ceramics by powder bed 3D printing N2 - Powder bed -based technologies are amongst the most successful Additive Manufacturing (AM) techniques. "Selective laser sintering/melting" (SLS/SLM) and "binder jetting 3D printing" (3DP) especially are leading AM technologies for metals and polymers, thanks to their high productivity and scalability. However, the flowability of the powder used in these processes is essential to achieve defect-free and densely packed powder layers. For standard powder bed AM technologies, this limits the use of many raw materials which are too fine or too cohesive. This presentation will discuss the possibilities to either optimize the powder raw material to adapt it to the specific AM process, or to develop novel AM technologies which are able to process powders in a wider range of conditions. In this context, the "layerwise slurry deposition" (LSD) has been developed as a layer deposition method which enables the use of very fine ceramic particles. T2 - Smart Made CY - Osaka, Japan DA - 01.09.2019 KW - Additive Manufacturing KW - Ceramic KW - Powder KW - Layerwise slurry deposition KW - 3D printing PY - 2019 AN - OPUS4-49221 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bernard, D. A1 - Léonard, Fabien A1 - Plougonven, E. A1 - Bruno, Giovanni T1 - On the use of autocorrelation functions, permeability tensors, and computed tomography to characterize the anisotropy of Diesel particulate filter materials N2 - 3D images such as those produces by X-ray tomography can provide a wealth of information on the internal structure of materials, but quantification of specific geometrical or topological characteristics linked to some bulk physical property is far from being straightforward. This study focuses on methods to quantify the differences in physical properties as a function of direction, i.e. their anisotropy, and how it can be linked to measures of anisotropy of the internal structure of the material. The auto-correlation function gives a similarity measure in the volume as a function of distance and direction. This is a cross-correlation of the image with itself fast to compute and relatively insensitive to noise. It is why we focus on this method to compare with the physical property of our DPF material. Diesel Particulate Filter (DPF) materials are porous ceramics that; a) can be used at very high temperatures; b) have very good thermal shock resistance; c) are inert; d) can be manufactured with tailored porosity. Their usual way of production consists of the extrusion of a slurry into the desired filter shape, with successive ceramming at high temperature. This process causes anisotropy at both microscopic and macroscopic levels. T2 - ICTMS 2019 CY - Cairns, Australia DA - 22.07.2019 KW - Structure-property relationship KW - Anisotropy estimate KW - Porous ceramics KW - Autocorrelation PY - 2019 AN - OPUS4-49226 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Mansfeld, Ulrich A1 - Pellegrino, F. A1 - Maurino, V. A1 - Marguet, S. A1 - Testard, F. A1 - Tache, O. A1 - Bartzcak, D. T1 - New reference material candidates for traceable size measurement of nonspherical nanoparticles N2 - Size measurement of nanoparticles (NP) becomes a challenging analytical problem when non-spherical shapes must be traceably measured. However, most industrial NPs have irregular shapes and broad size distribution making it often more complex to follow European regulatory to identify a material as a nanomaterial according to which accurate measurement of the smallest dimension and its size Distribution is necessary. The European research project nPSize - Improved traceability chain of nanoparticle size measurements aims to fill this gap by developing potential non-spherical reference nanoparticles, measurement procedures and physical modelling to improve the traceability chain, comparability and compatibility for NP size measurements between different methods. Therefore, new model NP with well-controlled shape has been synthesized and are supposed to be systematically characterized using the traceable methods scanning/transmission electron microscopy, atomic force microscopy and small angle X-ray scattering. Following NP candidates are under investigation with respect to their homogeneity and stability: (i) titania nanoplatelets (10-15 nm thickness x 50-100 nm lateral), (ii) titania bipyramides (~60 nm length x 40 nm width), (iii) titania acicular particles (100 nm length x 15-20 nm width; aspect ratio 5.5/6), (iv) gold nanorods (~10 nm width x 30 nm length), and (v) gold nanocubes (~55 nm x 55 nm x 55 nm). In addition, sample preparation procedures as well as measurement analysis procedures with evaluation of appropriate measurands and descriptors for each material class and method are being developed to support standardization. To underpin the traceability of the size measurement of nonspherical NP, physical modelling of the signals in e.g. electron microscopy techniques will be used and in combination, the implementation of machine learning is aimed to facilitate measurement Analysis procedures, especially regarding the accurate thresholding/segmentation of the NPs. T2 - European Conference on Applications of Surface and Interface Analysis ECASIA 2019 CY - Dresden, Germany DA - 15.09.2019 KW - Nanoparticles KW - Size distribution KW - Electron microscopy KW - Certified reference materials KW - Traceability PY - 2019 AN - OPUS4-49227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mieller, Björn T1 - Electrode area dependence of dielectric breakdown strength N2 - Dielectric breakdown of ceramics is widely believed to originate from microstructural defects. Still, there is no commonly accepted model for the origin and process of dielectric failure that covers all observed phenomena and dependencies. In analogy to mechanical strength, the Weibull distribution is commonly used to evaluate dielectric strength data. This works well for a given group of specimens with constant geometry. But unlike mechanical strength, dielectric strength scales with the inverse square root of sample thickness. This cannot be explained by the classic Weibull concept. The Griffith type energy release rate model of dielectric breakdown proposed by Schneider is based on space charge injection and conducting filaments from the sample surface. This model incorporates the distinct thickness dependence and the pronounced influence of surface defects. Based on this model and the classic Weibull probability of failure, Schneider’s group theoretically derived a probability of breakdown that predicts an increase of failure probability with increasing electrode area. In our study we tested this model with dielectric strength data measured on dense alumina samples using different electrode areas. Weibull modulus and characteristic dielectric strength (scale parameter) were determined for a set of measurements using small electrodes. These values were used to calculate the failure probability under large electrodes according to the model. The calculated data excellently fits the measured values. Thus, our experiments substantiate the assumptions made in the breakdown model and the significance of surface defects for dielectric failure. T2 - 94. DKG Jahrestagung CY - Leoben, Austria DA - 05.05.2019 KW - Dielectric strength KW - Breakdown strength KW - Ceramics PY - 2019 AN - OPUS4-48015 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogl, Jochen T1 - What isotopes can do... N2 - The talk gives Brief overview on the effects causing isotope variations in nature and some typical applications. It also Points to a potential application in corrosin sciences. T2 - Final Colloquium: Microbiologically influenced corrosion CY - Berlin, Germany DA - 21.05.2019 KW - Iron isotope fractionation KW - Microbially induced corrosion PY - 2019 AN - OPUS4-48273 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fayet, G. A1 - Rotureau, P. A1 - Wehrstedt, Klaus-Dieter A1 - Knorr, Annett T1 - Predictive Methods for Determining the Thermal Decomposition Properties of Hazardous Substances N2 - Due to the fast development and availability of computers, predictive approaches are increasingly used in the evaluation process of hazardous substances complementary to experiments. Their use was recommended as alternative to experimental testing by the REACH regulation to complete the lack of knowledge on properties for existing substances that must be registered before 2018 (upon quantities). Among the proposed predictive approaches, Quantitative Structure Property Relationships (QSPR) are powerful methods to predict macroscopic properties from the only molecular structure of substances. In that context, the HAZPRED project (2015-2018, founded by the SAF€RA consortium) aims to develop theoretical models (e.g. QSPR) and small-scale tests to predict complex physico-chemical properties (e.g. thermal stability, explosivity) of hazardous substances to complete the lack of knowledge on these hazardous substances quickly or to understand their decomposition behaviour better. In particular, this contribution will present the work done in this project on the physical hazards of organic peroxides and self-reactive substances: gathering of existing experimental data, new experimental campaigns, review of existing models and proposition of new estimation methods. T2 - 16th International Symposium on Loss Prevention and Safety Promotion in the Process Industries CY - Delft, The Netherlands DA - 16.06.2019 KW - Self-reactive substances KW - QSPR KW - HAZPRED KW - Organic peroxides PY - 2019 AN - OPUS4-49509 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koerdt, Andrea A1 - An, Biwen Annie A1 - Kleinbub, Sherin A1 - Herrmann, Annett T1 - Investigation of methanogen-induced microbiologically influenced corrosion (Mi-MIC) using simulated marine environments under flowing conditions N2 - Microbiologically influenced corrosion (MIC) of iron is usually attributed to sulfate-reducing microorganisms (SRM) in offshore industries, such as the oil and gas pipelines, due to the high concentrations of sulfate in the seawater. SRM act upon the metal by the reactiveness of hydrogen sulfide (HS-), and by withdrawal of the available electrons (Fe --> Fe2+ + 2e-; E° = -0.47 V) in electrical contact with the metal (EMIC). However, methanogenic archaea can also cause MIC. Because they do not produce HS-, withdrawal of electrons may be their main corrosive mechanism; however, mechanistic details and kinetics of the overall process are poorly understood. To investigate the corrosion potential of methanogens, we studied the EMIC methanogenic strains isolated from marine sediments (Methanobacterium-affiliated strain IM1) and crude oil tanks (Methanococcus maripaludis Mic1c10), in an in-house developed flow-through cell to simulate a fluctuating environment. A co-culture of M. maripaludis and D. alaskensis was also established to study the effect of syntrophic growth on metal corrosion that may occur in industrial pipelines. Results indicate that the rates of iron corrosion due to coupled methanogenesis (up to 0.4 mm/yr) are higher to that caused by the marine SRM Desulfovibrio alaskensis (0.15 mm/yr). Surface analyses of the metal showed severe pitting with high methane production. Genomic analysis of the EMIC methanogen M. maripaludis Mic1c10 will provide an insight on the mechanisms of MIC. Such knowledge and deeper understanding also from an electrokinetic point of view may not only provide further models in microbial electrophysiology, but also contribute to mitigation strategies in MIC T2 - Einladung zum Kolloquium HZDR – Helmholtz-Zentrum Dresden-Rossendorf CY - Dresden, Germany DA - 24.09.2019 KW - Corrosion KW - MIC KW - Archaea KW - Methanogens KW - Environmental Simulation PY - 2019 AN - OPUS4-49403 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit A1 - Simon, Sebastian A1 - Sigmund, Sandra A1 - Ziemann, M. A. A1 - von Werder, Julia T1 - Characterization of Alkali-Silica Reaction Products by means of Raman Spectroscopy before and after Application of Accelerated Tests N2 - Alkali silica reaction (ASR) is a major concrete durability problem resulting in significant maintenance and reconstruction costs for concrete infrastructures all over the world. To determine whether an aggregate is potentially reactive, accelerated concrete tests are used. Aim of this study is the chemical and microstructural characterization of ASR-products formed under the performance conditions of motorway pavements and during subsequent tests on the remaining ASR susceptibility. Samples were taken from concrete motorway pavements. Some of the samples already showed first indications for beginning damages whereas others showed deteriorations only after applying a performance testing procedure for the estimation of future risk of ASR damage. In a first step ASR-products were identified by polarized light microscopy in thin sections. The reaction products where then analyzed by Raman Spectroscopy and finally the chemical composition of the ASR-products was identified by SEM with EDX. The results indicate that most reaction products show an increasing Ca/Si-ratio with progressive crack length. If an ASR-product develops inside an aggregate and moves through the cement paste, it has a high (Na+K)/Si-ratio at the beginning which decreases with increasing distance from its place of origin. The Raman spectra of the ASR-products are characterized by two broad bands indicating specific Q-species of different amorphous gel networks. Within the scope of the analysis distinctions in the microstructure and the chemical composition of the ASR-gels were detected relating to various conditions of accelerated testing. T2 - 15th International Congress on Chemistry of Cement CY - Prague, Czech Republic DA - 16.09.2019 KW - Alkali-silica reaction KW - Raman microscopy KW - Microstructure KW - Concrete motorway pavements KW - Performance test PY - 2019 AN - OPUS4-49527 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waurischk, Tina A1 - Balzer, R. A1 - Kiefer, P. A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Behrens, H. A1 - Deubener, J. T1 - Subcritical crack growth in hydrous silicate glass N2 - Ambient water influences sub-critical crack growth (SCCG) from microscopic surface flaws, leading to stress corrosion at the crack tip. The complex influence of humidity accelerating slow crack propagation (region I) is well studied only for dry commercial NCS glass (< 1000 ppm water). To shed light on this influence, the effect of water is mimicked by studying SCCG water-bearing glasses. For this purpose, water-bearing silicate glasses of 8 wt% total water were synthesized at 0.5 GPa and compared to dry glasses. SCCG was measured in double cantilever beam geometry. For dry glasses, 3 trends in crack velocity vs. stress intensity, KI, curve were found. The slope in region I increases in the order NCS < NBS < BaCS < NZnS < NAS glass. The velocity range of region II, reflecting the transition between corrosion affected and inert crack growth (region III), varies within one order of magnitude among these glasses. The KI region of inert crack growth strongly scatters between 0.4 and 0.9 MPam0.5. For hydrous glasses, it is found that water strongly decreases Tg, form a new sub-Tg internal friction peak caused by molecular water, and makes the glasses more prone to SCCG. The observed trends will be discussed in terms of the effects of Youngs Modulus on the strain energy release rate and energy dissipation related to mechanical glass relaxation phenomena. T2 - 25th International Congress on Glass (ICG2019) CY - Boston, MA, USA DA - 09.06.2019 KW - Internal friction KW - Soda-lime silicate glass KW - Crack growth KW - Water content KW - DCB PY - 2019 AN - OPUS4-49536 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kiefer, P. A1 - Deubener, J. A1 - Waurischk, Tina A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Behrens, H. A1 - Balzer, R. T1 - Density, microhardness and elastic moduli of hydrous soda-lime silicate glasses N2 - The effect of structural water on density, elastic constants and microhardness of water-bearing soda-lime-silica glasses of up to 21.5 mol% total water is studied. T2 - 25th International Congress on Glass (ICG2019) CY - Boston, MA, USA DA - 09.06.2019 KW - Elastic constants KW - Soda-lime-silica glass KW - Water content KW - Microhardness PY - 2019 AN - OPUS4-49537 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -