TY - JOUR A1 - Kühling, J. A1 - Niebergall, Ute A1 - Calmez, D. A1 - Schnorr, W. A1 - Schmidt, J. T1 - Die distale Unterschenkelverriegelungsnagelung - eine statische Prüfung JF - Aktuelle Traumatologie N2 - Studienziel: Zwei Nagelsysteme, zum einen der unaufgebohrte Tibianagel mit 3fach-Verriegelung in 2 Ebenen und großem Bolzenspiel (UTN® der Fa. Mathys®) mit der Möglichkeit von medial zweifach und von ventral einfach zu verriegeln und zum anderen der unaufgebohrte Tibianagel mit 3fach-Verriegelung in einer Ebene mit geringem Bolzenspiel (Targon®-Nagel der Fa. Aesculap®), der 3 mediale Verriegelungsmöglichkeiten besitzt, wurden im Biegeversuch statisch geprüft. Anatomisch besteht bei der ventralen Verriegelung immer die Verletzungsmöglichkeit von Sehnen, Nerven und Gefäßen. Andererseits besteht bei einem „höheren Bolzenspiel“ immer ein höherer Instabilitätsgrad. Inwieweit ist die Verriegelung in zwei Ebenen notwendig? Methode: Wir prüften statisch zwei intramedulläre Verriegelungssysteme an 8 Leichenknochen (matched pairs) in zwei Ebenen an einer Universalprüfmaschine der Firma Schenk-Trebel im Biegeversuch. Ergebnisse: Die Untersuchungsergebnisse zeigen, dass nicht die Bolzenlage, sondern das so genannte „Bolzenspiel“ für die Stabilität der distalen Fragmente entscheidend ist. Die Verriegelung sollte somit prinzipiell durch ein formschlüssiges winkelstabiles Bolzensystem möglich sein. PY - 2004 DO - https://doi.org/10.1055/s-2004-817964 SN - 0044-6173 SN - 1438-9436 SN - 0935-0705 VL - 34 SP - 71 EP - 77 PB - Thieme CY - Stuttgart AN - OPUS4-3533 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, J. A1 - Letsch, R. A1 - Kühling, J. A1 - Baranek, T. A1 - Niebergall, Ute A1 - Bogusch, G. T1 - Stability of Screw Fixation of Femoral Neck Fractures - A Biomechanical Trial JF - Osteosynthesis and trauma care N2 - With a growing percentage of elderly people in the population and, correspondingly, an increasing rate of fractures of the proximal femur, the question how to stabilize medial femoral-neck fractures is gaining increasing importance. Especially in Hungary and Scandinavian countries, femoral-head-preserving surgery is advocated. However, the main problems of this procedure are re-dislocation and necrosis of the femoral head. Encouraged by two theoretical mathematical considerations, a biomechanical experiment was performed to investigate two different methods of screw fixation of medial femoral-neck fractures. The results showed that a head-preserving internal fixation with two cranial screws and a three-point supported screw at the bottom of the neck had distinct biomechanical advantages compared to conventional screw fixation. This has encouraged us to more frequently perform this minimally invasive and head-preserving surgery in Pauwels I and II medial fractures of the femoral head. KW - Femoral neck fracture KW - Screw fixation KW - Biomechanical stability KW - Cadaver experiment KW - Mathematical model PY - 2005 DO - https://doi.org/10.1055/s-2005-836332 SN - 1618-971X VL - 13 IS - 2 SP - 76 EP - 81 PB - Thieme CY - Stuttgart AN - OPUS4-10843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosemann, P. A1 - Bender, S. A1 - Heyn, Andreas A1 - Schmidt, J. T1 - Korrosion and Biokompatibilität beschichteter MgCa1,0 Magnesiumlegierungen T2 - 14. Sommerkurs Werkstoffe und Fügen am Institut für Werkstoff- und Fügetechnik N2 - Die Magnesiumlegierung Mg-Cal besitzt als potentielles bioabsorbierbares Implantatmaterial die Möglichkeit, vollständig vom menschlichen Körper absorbiert zu werden. Die mechanischen Kennwerte dieser Legierung liegen im Bereich des menschlichen Knochens und beide Legierungselemente (Mg, Ca) sind essentielle Spurenelemente im menschlichen Organismus. Der limitierende Faktor für den Einsatz ist die hohe Degradationsrate dieser Legierung. Um die Degradationsgeschwindigkeit zu verringern, wurden zwei Beschichtungssysteme auf Grundlage der Plasmachemischen Oxidation (PCO) und organischer Beschichtung erzeugt und untersucht. Das Korrosionsverhalten dieser Schichtsysteme wurde dabei mit dem Elektrochemischen Rauschen analysiert. Zusätzlich wurde der Einfluss von Wasserstoffentwicklung und eines ansteigenden pHWert auf die Zelltoxizität untersucht. Die Ergebnisse zeigen, dass eine Kombination von beiden Schichtsystemen zu einem viel versprechenden Degradationsverhalten führt. T2 - 14. Sommerkurs Werkstoffe und Fügen am Institut für Werkstoff- und Fügetechnik CY - Magdeburg, Germany DA - 23.09.2011 KW - Magnesium KW - Magnesium-Calcium KW - Implantat KW - Beschichtung KW - Plasmachemische Oxidation KW - Korrosion KW - Elektrochemisches Rauschen PY - 2011 SN - 978-3-940961-56-3 SP - 135 EP - 138 AN - OPUS4-24491 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Debatin, F. A1 - Behrens, K. A1 - Weber, J. A1 - Baburin, I. A. A1 - Thomas, A. A1 - Schmidt, J. A1 - Senkovska, I. A1 - Kaskel, S. A1 - Kelling, A. A1 - Hedin, N. A1 - Bacsik, Z. A1 - Leoni, S. A1 - Seifert, G. A1 - Jäger, Christian A1 - Günter, C. A1 - Schilde, U. A1 - Friedrich, A. A1 - Holdt, H.-J. T1 - An isoreticular family of microporous metal-organic frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate: syntheses, structures and properties JF - Chemistry - A European journal N2 - We report on a new series of isoreticular frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate (IFP-1–4, IFP=imidazolate framework Potsdam) that form one-dimensional, microporous hexagonal channels. Varying R in the 2-substitued linker (R=Me (IFP-1), Cl (IFP-2), Br (IFP-3), Et (IFP-4)) allowed the channel diameter (4.0–1.7 Å), the polarisability and functionality of the channel walls to be tuned. Frameworks IFP-2, IFP-3 and IFP-4 are isostructural to previously reported IFP-1. The structures of IFP-2 and IFP-3 were solved by X-ray crystallographic analyses. The structure of IFP-4 was determined by a combination of PXRD and structure modelling and was confirmed by IR spectroscopy and 1H MAS and 13C CP-MAS NMR spectroscopy. All IFPs showed high thermal stability (345–400°C); IFP-1 and IFP-4 were stable in boiling water for 7 d. A detailed porosity analysis was performed on the basis of adsorption measurements by using various gases. The potential of the materials to undergo specific interactions with CO2 was investigated by measuring the isosteric heats of adsorption. The capacity to adsorb CH4 (at 298 K), CO2 (at 298 K) and H2 (at 77 K) at high pressure were also investigated. In situ IR spectroscopy showed that CO2 is physisorbed on IFP-1–4 under dry conditions and that both CO2 and H2O are physisorbed on IFP-1 under moist conditions. KW - Adsorption KW - Metal-organic frameworks KW - Microporous materials KW - N,O ligands KW - Zinc PY - 2012 DO - https://doi.org/10.1002/chem.201200889 SN - 0947-6539 SN - 1521-3765 VL - 18 IS - 37 SP - 11630 EP - 11640 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-27725 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kühling, J. A1 - Schmidt, J. A1 - Dahn, T. A1 - Niebergall, Ute A1 - Bogusch, G. T1 - Die kopferhaltende operative Versorgung der traumatischen medialen Schenkelhalsfraktur mit Großfragmentschrauben - eine biomechanische Prüfung JF - Zeitschrift für Orthopädie und ihre Grenzgebiete N2 - Studienziel: Bei der zunehmenden Überalterung der Bevölkerung und der zunehmenden Inzidenz an hüftgelenknahen Oberschenkelfrakturen nimmt die Frage der Versorgung der medialen Schenkelhalsfraktur eine zunehmende Rolle ein. Vor allem aus Ungarn und den skandinavischen Ländern wird die kopferhaltende Therapie propagiert. Das Redislozieren dieser Frakturen und die Hüftkopfnekrose sind jedoch dagegenstehende Probleme. Methode: Ermutigt durch zwei theoretische mathematische Überlegungen wurden in einem biomechanischen Experiment zwei verschiedene Möglichkeiten der Verschraubung der medialen Schenkelhalsfraktur erprobt. Ergebnisse: Als Ergebnis zeigte sich, dass eine kopferhaltende Versorgung mit 2 kranial liegenden Schrauben und einer dreipunktabgestützten Schraube am Adam'schen Bogen deutliche biomechanische Vorteile hat gegenüber der herkömmlichen Verschraubung. Schlussfolgerung: Dies ermutigt uns, zunehmend die minimalinvasive und kopferhaltende Versorgung der medialen Schenkelhalsfraktur insbesondere bei Pauwels-I- und II-Verletzungen einzusetzen. KW - Mediale Schenkelhalsfraktur KW - Schraubenosteosynthese KW - Biomechanik KW - Medial hip fracture KW - Osteosynthesis with screw KW - Biomechanics PY - 2005 DO - https://doi.org/10.1055/s-2005-836807 SN - 0044-3220 VL - 143 SP - 412 EP - 418 PB - Thieme CY - Stuttgart AN - OPUS4-10755 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosemann, P. A1 - Schmidt, J. A1 - Heyn, Andreas T1 - Short and long term degradation behaviour of Mg-1Ca magnesium alloys and protective coatings based on plasma-chemical oxidation and biodegradable polymer coating in synthetic body fluid JF - Materials and corrosion N2 - The main problem limiting the application of magnesium alloys as biodegradable implant material is its high degradation rate. In order to slow down the corrosion rate an extrusion process and specific coating systems based on plasma-chemical oxidation (PCO) and organic dip coating with poly(ʟ-lactid-co-caprolacton) (PLLC) were applied on Mg–1Ca magnesium alloy. The additional PLLC coating is used to delay the start of substrate corrosion, while the purpose of the PCO coating is to decrease the substrate corrosion rate. The corrosion behaviour was investigated in synthetic body fluid (SBF) through measurement of the hydrogen evolution rate in long term tests and polarisation and electrochemical noise measurements in short term tests. The results showed significant differences between the cast and extruded alloys and a decrease of the corrosion rate due to corrosion product formation. The combination of both coating systems resulted in a significant delay of metal substrate corrosion and all coating systems showed good correlation between short and long term tests. The combination of the three investigation methods provides the possibility to gain more information about the degradation behaviour and break down of protective coatings. KW - Coatings KW - Corrosion KW - Electrochemical noise KW - Magnesium KW - Plasma-chemical oxidation PY - 2013 DO - https://doi.org/10.1002/maco.201206590 SN - 0947-5117 SN - 1521-4176 VL - 64 IS - 8 SP - 714 EP - 722 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-29074 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bender, S. A1 - Göllner, J. A1 - Heyn, Andreas A1 - Heilmaier, M. A1 - Schmidt, J. ED - Kainer, K.U. T1 - Basic examinations of pre-treatment and coating of magnesium alloys T2 - Magnesium T2 - 8th International conference on magnesium alloys and their applications CY - Weimar, Germany DA - 2009-10-26 KW - Magnesium KW - Korrosion KW - Beschichtung KW - Vorbehandlung KW - Elektrochemisches Rauschen PY - 2010 SN - 978-3-527-32732-4 SP - 1323 EP - 1330 PB - Wiley-VCH AN - OPUS4-20743 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmigalla, S. A1 - Bender, S. A1 - Heyn, Andreas A1 - Schmidt, J. A1 - Hort, N. T1 - Investigation of biodegradation behaviour of an Mg-1Ca alloy influenced by heat treatment and applying plasma-chemical oxidation layers JF - Materials and corrosion N2 - The degradation behaviour of an Mg-1Ca alloy is investigated in vitro to figure out the possibilities of influencing the degradation behaviour of such an alloy by applying heat treatment as well as the use of a coating system based on plasma-chemical oxidation. It is shown that an optimised solution annealing (T4-heat treatment) can reduce the degradation rate while an additional ageing between 240 and 300 °C (T6-heat treatment) increases it. A coating generated by plasma-chemical oxidation reduces the degradation rate in the immersion test. Its effect is depending on the former heat treatment of the Mg-1Ca alloy as well as on the parameter during plasma-chemical oxidation. KW - Biodegradation KW - Magnesium alloys KW - Plasma-chemical oxidation KW - Magnesium KW - Thermal treatment KW - Corrosion KW - Electrochemistry PY - 2013 DO - https://doi.org/10.1002/maco.201106433 SN - 0947-5117 SN - 1521-4176 VL - 64 IS - 7 SP - 578 EP - 584 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-28933 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, M. A1 - Schlingmann, T. A1 - Schmidt, J. A1 - Bettge, Dirk A1 - Hilgenberg, Kai A1 - Binder, M. A1 - Klöden, B. T1 - A Round Robin Test To Investigate The Printing Quality Of PBF LB/M Processed AlSi10Mg N2 - When it comes to higher accuracies, new technologies and real applications in additive manufacturing, there is one topic which cannot be avoided: The material response on the chosen processing parameters and its agreement and correspondence with literature data of the wrought material grade counterpart. In industrial Additive Manufacturing (AM) standards in terms of printing parameters, protection gas atmospheres or powder handling instructions are not obligatory. Therefore, the question must be answered whether the AM process is reproducible and reliable over different printing companies. This was the motivation to realize a round robin test between 8 European printing companies and academic partners. The consortium had printed and tested fatigue and tensile testing bars under plant-specific conditions. A commonly used cast aluminum alloy, AlSi10Mg, was chosen as test material for the PBF-LB/M process. Differences of the results between the partners and the scatter itself were discussed in detail. T2 - World PM2022 CY - Lyon, France DA - 09.10.2022 KW - Additive manufacturing KW - AlSi10Mg KW - Laser powder bed fusion KW - Round robin KW - Reproducibility PY - 2022 AN - OPUS4-56303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, M. A1 - Schlingmann, T. A1 - Schmidt, J. A1 - Bettge, Dirk A1 - Hilgenberg, Kai A1 - Binder, M. A1 - Klöden, B. T1 - A Round Robin Test To Investigate The Printing Quality Of PBF-LB/M Processed AlSi10Mg T2 - World PM2022 N2 - When it comes to higher accuracies, new technologies and real applications in additive manufacturing, there is one topic which cannot be avoided: The material response on the chosen processing parameters and its agreement and correspondence with literature data of the wrought material grade counterpart. In industrial Additive Manufacturing (AM) standards in terms of printing parameters, protection gas atmospheres or powder handling instructions are not obligatory. Therefore, the question must be answered whether the AM process is reproducible and reliable over different printing companies. This was the motivation to realize a round robin test between 8 European printing companies and academic partners. The consortium had printed and tested fatigue and tensile testing bars under plant-specific conditions. A commonly used cast aluminum alloy, AlSi10Mg, was chosen as test material for the PBF-LB/M process. Differences of the results between the partners and the scatter itself were discussed in detail. T2 - World PM2022 CY - Lyon, France DA - 09.10.2022 KW - Additive manufacturing KW - Round robin KW - Reproducibility KW - Laser powder bed fusion KW - AlSi10Mg PY - 2022 SN - 978-1-899072-54-5 SP - 1 EP - 10 PB - European Powder Metallurgy Association (EPMA) AN - OPUS4-56304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, L. M. A1 - Müller, J. T. A1 - Smales, Glen Jacob A1 - Pauw, Brian Richard A1 - Schmidt, J. A1 - Bekheet, M. F. A1 - Gurlo, A. A1 - Simon, U. T1 - Hierarchically porous and mechanically stable monoliths from ordered mesoporous silica and their water filtration potential JF - Nanoscale Advances N2 - Mechanically stable structures with interconnected hierarchical porosity combine the benefits of both small and large pores, such as high surface area, pore volume, and good mass transport capabilities. Hence, lightweight micro-/meso-/macroporous monoliths are prepared from ordered mesoporous silica COK-12 by means of spark plasma sintering (SPS, S-sintering) and compared to conventionally (C-) sintered monoliths. A multi-scale model is developed to fit the small angle X-ray scattering data and obtain information on the hexagonal lattice parameters, pore sizes from the macro to the micro range, as well as the dimensions of the silica population. For both sintering techniques, the overall mesoporosity, hexagonal pore ordering, and amorphous character are preserved. The monoliths' porosity (77–49%), mesopore size (6.2–5.2 nm), pore volume (0.50–0.22 g cm-3 ), and specific surface area (451–180 m2 g-1) decrease with increasing processing temperature and pressure. While the difference in porosity is enhanced, the structural parameters between the C-and S-sintered monoliths are largely converging at 900 C, except for the mesopore size and lattice parameter, whose dimensions are more extensively preserved in the S-sintered monoliths, however, coming along with larger deviations from the theoretical lattice. Their higher mechanical properties (biaxial strength up to 49 MPa, 724 MPa HV 9.807 N) at comparable porosities and ability to withstand ultrasonic treatment and dead-end filtration up to 7 bar allow S-sintered monoliths to reach a high permeance (2634 L m-2 h-1 bar-1), permeability (1.25 x 10^-14 m2), and ability to reduce the chemical oxygen demand by 90% during filtration of a surfactant-stabilized oil in water emulsion, while indicating reasonable resistance towards fouling. KW - SAXS KW - Hierarchically porous KW - Silica KW - Water filtration PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555928 DO - https://doi.org/10.1039/D2NA00368F SN - 2516-0230 SP - 1 EP - 17 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-55592 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosemann, P. A1 - Bender, S. A1 - Heyn, Andreas A1 - Schmidt, J. T1 - In vitro corrosion and biocompatibility of coated MgCa1.0 magnesium alloys JF - Materials science forum N2 - As bio-absorbable implant material the magnesium alloy Mg-1Ca is able to degrade in-vivo. The mechanical properties of this alloy are similar to those of human bone; both Mg and Ca are essential elements in human body. The main problem is the high corrosion rate of this alloy. Two coating systems based on plasma-chemical oxidation and an organic dip coating are applied onto MgCa1.0 magnesium alloy in order to slow down the corrosion rate. The corrosion behaviour of the coated alloys was investigated with electrochemical noise measurements. The influence of hydrogen evolution and increasing pH-value on the cytotoxicity was examined. The results of these investigations suggest that a combination of both coating systems leads to promising degradation properties. KW - Biocompatibility KW - Biodegradation KW - Magnesium KW - Plasma-Chemical Oxidation PY - 2011 DO - https://doi.org/10.4028/www.scientific.net/MSF.690.409 SN - 0255-5476 VL - 690 SP - 409 EP - 412 PB - Trans Tech Publications CY - Aedermannsdorf, Switzerland AN - OPUS4-23875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, D. A1 - Konnertz, Nora A1 - Böhning, Martin A1 - Schmidt, J. A1 - Thomas, A. T1 - Light-switchable polymers of intrinsic microporosity JF - Chemistry of Materials N2 - The interest in (micro)porous systems is greater than ever before with microporous polymers finding application in areas such as gas storage/separation and catalysis. In contrast to the vast majority of publications on microporous polymers seeking ever higher values for surface area or uptake capacity for a particular gas, this work presents a means to render a microporous system responsive to electromagnetic stimuli. The incorporation of a diarylethene (DAE) derivative in the backbone of a polymer of intrinsic microporosity (PIM) produces a microporous system that exhibits photochromism as proven by UV–vis absorption and NMR studies. In the resulting DAE-PIM, surface area is not a fixed unalterable property but can be influenced by the external and nondestructive stimulus light in a reversible manner. Furthermore, in combination with Matrimid, free-standing membranes can be produced that display light-switchable diffusivity and permeability for carbon dioxide and oxygen. In this way, material scientists are offered the potential to employ only one system that can assume several states with different properties for each. KW - Gaspermeation KW - Diffusion KW - Polymer intrinsischer Mikroporosität KW - UV-VIS PY - 2016 DO - https://doi.org/10.1021/acs.chemmater.6b02619 SN - 0897-4756 VL - 28 IS - 23 SP - 8523 EP - 8529 PB - ACS CY - Whashington,DC AN - OPUS4-38735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strüder, L. A1 - Hartmann, R. A1 - Holl, P. A1 - Ihle, S. A1 - Huth, M. A1 - Schmidt, J. A1 - Tham, Ch. A1 - Kanngießer, B. A1 - Baumann, J. A1 - Renno, A. A1 - Grenzer, J. A1 - Radtke, Martin A1 - Abboud, A. A1 - Pietsch, U. A1 - Soltau, H. T1 - High Speed, High Resolution imaging spectrometers based on pnCCDs for XRF and XRD applications JF - Microscopy and Microanalysis N2 - For many years pnCCDs have been well known as X-ray detectors for spectroscopic imaging in many fields of science: X-Ray Fluorescence analysis (XRF), X-ray Diffraction (XRD) with light sources in large accelerator facilities as well as with laboratory light sources or with X-rays from celestial sources in X-ray astronomy. A brief introduction in GEXRF (Grazing Emission XRF) measurements with a laboratory laser produced plasma source will be given, PIXE (Particle Induced X-ray Emission) measurements and D2XRF (Double Dispersive X-Ray Fluorescence) and Slicing experiments with pnCCDs coupled to polycapillary optics performed at the BESSY synchrotron will be shown. Energy-dispersive Laue diffraction with ultra-hard X-rays for the analysis of defects in metals will conclude the overview of spectroscopic X-ray imaging measurements in the field of structure and dynamics of matter. KW - PnCCD KW - Synchrotron KW - XRF PY - 2016 DO - https://doi.org/10.1017/S1431927616001355 VL - 22 IS - S3 SP - 100 EP - 101 AN - OPUS4-38884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Elsayed, H. A1 - Zocca, Andrea A1 - Schmidt, J. A1 - Günster, Jens A1 - Colombo, P. A1 - Bernardo, E. T1 - Bioactive glass-ceramic scaffolds by additive manufacturing and sinter-crystallization of fi ne glass powders JF - Journal Materials Research N2 - Wollastonite (CaSiO 3 ) – diopside (CaMgSi 2 O 6 ) glass-ceramic scaffolds have been successfully fabricated using two different additive manufacturing techniques: powder-based 3D printing (3DP) and digital light processing (DLP), coupled with the sinter-crystallization of glass powders with two different compositions. The adopted manufacturing process depended on the balance between viscous flow sintering and crystallization of the glass particles, in turn in fluenced by the powder size and the sensitivity of CaO – MgO – SiO 2 glasses to surface nucleation. 3DP used coarser glass powders and was more appropriate for low temperature firing (800 – 900 °C), leading to samples with limited crystallization. On the contrary, DLP used finer glass powders, leading to highly crystallized glass-ceramic samples. Despite the differences in manufacturing technology and crystallization, all samples featured very good strength-to-density ratios, which bene fit theiruse for bone tissue engineering applications. The bioactivity of 3D-printed glass-ceramics after immersion in simulated body fluid and the similarities, in terms of ionic releases and hydroxyapatite formation with already validated bioactive glass-ceramics, were preliminarily assessed. KW - 3D-Printing KW - Bio Ceramic KW - Additive manufacturing PY - 2018 DO - https://doi.org/10.1557/jmr.2018.120 SN - 2044-5326 SN - 0884-2914 VL - 33 IS - 14 SP - 1960 EP - 1971 PB - Cambridge University Press AN - OPUS4-45718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, L. M. A1 - Diaz Cubas, D. A1 - Colmenares, M. G. A1 - Schmidt, J. A1 - Bekheet, M. F. A1 - Pauw, Brian Richard A1 - Gurlo, A. A1 - Simon, U. T1 - High specific surface area ordered mesoporous silica COK-12 with tailored pore size JF - Microporous and Mesoporous Materials N2 - Ordered mesoporous silica materials such as COK-12, analogous to the well-known SBA-15, are characterized by high surface areas and unique features such as defined pore sizes in the meso-size range and high pore ordering. The aim of this work was to prove the washing step and choice of calcination and aging temperature during the COK-12 synthesis as effective tools in tailoring, markedly improving the specific surface area, pore size, and pore volume. By controlling the aging temperature, the pore size was linearly adjusted between 5.7 and 8.1 nm, while preserving the hexagonal ordering of the pores. The synthesized COK-12 powders possess pore volumes and specific surface areas up to 1.23 cm3 g−1 and 860m2 g−1, respectively, which is markedly higher than what has previously been reported about COK-12. The presented results and the environmentally friendly character of the synthesis will make COK-12 more interesting for future adaption to the industrial processes, for example in catalysis, adsorption, or drug delivery. KW - Ordered mesoporous silica KW - Pore size tailoring KW - High specific surface area KW - SAXS KW - Small angle scattering PY - 2019 DO - https://doi.org/10.1016/j.micromeso.2019.01.050 SN - 1387-1811 VL - 280 SP - 133 EP - 143 PB - Elsevier AN - OPUS4-47378 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Colombo, P. A1 - Schmidt, J. A1 - Franchin, G. A1 - Zocca, Andrea A1 - Günster, Jens T1 - Additive manufacturing techniques for fabricating complex ceramic components from preceramic polymers JF - American Ceramic Society Bulletin N2 - Capsule summary THE MATERIALS Manufacturers can use preceramic polymers to produce ceramic components in a range of compositions using a variety of additive manufacturing technologies. Preceramic polymers even can overcome some of the problems that are intrinsic to additive manufacturing in general. THE APPLICATION Modifying the composition, molecular architecture, and molecular weight of preceramic polymers allows adaptation of these materials to specific processing requirements of individual additive manufacturing technologies. THE OPPORTUNITY Further development of new additive manufacturing technologies, in addition to improvement of existing technologies, will enable manufacturing of advanced ceramic components with enhanced mechanical characteristics and new functional properties. KW - Additive manufacturing KW - Preceramic polymers PY - 2017 VL - 96 IS - 3 SP - 16 EP - 23 AN - OPUS4-40747 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, M. A1 - Bettge, Dirk A1 - Hilgenberg, Kai A1 - Binder, M. A1 - Dollmeier, K. A1 - Dreyer, M. A1 - Klöden, B. A1 - Schlingmann, T. A1 - Schmidt, J. T1 - Reproducibility and Scattering in Additive Manufacturing: Results from a Round Robin on PBF-LB/M AlSi10Mg Alloy T1 - Reproduzierbarkeit und Streuung bei der additiven Fertigung: Ergebnisse eines Ringversuchs mit einer PBF-LB/M AlSi10Mg-Legierung JF - Practical Metallography N2 - The round robin test investigated the reliability users can expect for AlSi10Mg additive manufactured specimens by laser powder bed fusion through examining powder quality, process parameter, microstructure defects, strength and fatigue. Besides for one outlier, expected static material properties could be found. Optical microstructure inspection was beneficial to determine true porosity and porosity types to explain the occurring scatter in properties. Fractographic analyses reveal that the fatigue crack propagation starts at the rough as-built surface for all specimens. Statistical analysis of the scatter in fatigue using statistical derived safety factors concludes that at a stress of 36.87 MPa the fatigue limit of 107 cycles could be reached for all specimen with a survival probability of 99.999 %. N2 - Im Rahmen eines Ringversuchs wurde durch die Untersuchung der Pulverqualität, der Prozessparameter, der Gefügefehler, der Festigkeit und der Ermüdung die Zuverlässigkeit bestimmt, die Nutzer von AlSi10Mg-Proben erwarten können, die mit pulverbettbasiertes Schmelzen mittels Laser (engl. Laser Powder Bed Fusion) gefertigt worden sind. Abgesehen von einem Ausreißer wurden die erwarteten statischen Materialeigenschaften erreicht. Eine optische Gefügeprüfung diente dazu, die tatsächliche Porosität und Arten von Porosität zu ermitteln, um die bei den Eigenschaften auftretende Streuung zu erklären. Fraktographische Unterschungen zeigen eine bei allen Proben von der rauen Oberfläche im As-built-Zustand ausgehende Ermüdungsrissausbreitung. Aus der statistischen Analyse der Streuung bezüglich der Ermüdung unter Anwendung von statistischen abgeleiteten Sicherheitsfaktoren geht hervor, dass alle Proben die Dauerfestigkeit von 107 Zyklen bei einer Spannung von 36,87 MPa mit einer Überlebenswahrscheinlichkeit von 99,999 % erreichten. KW - Additive manufacturing KW - Reproducibility KW - Reliability PY - 2022 DO - https://doi.org/10.1515/pm-2022-1018 SN - 2195-8599 VL - 59 IS - 10 SP - 580 EP - 614 PB - De Gruyter AN - OPUS4-55935 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Juds, Carmen A1 - Schmidt, J. A1 - Weller, Michael G. A1 - Lange, Thorid A1 - Beck, Uwe A1 - Conrad, T. A1 - Boerner, H. G. T1 - Combining phage display and next-generation sequencing for materials sciences: A case study on probing polypropylene surfaces JF - Journal of the American Chemical Society N2 - Phage display biopanning with Illumina next-generation sequencing (NGS) is applied to reveal insights into peptide-based adhesion domains for polypropylene (PP). One biopanning round followed by NGS selects robust PP-binding peptides that are not evident by Sanger sequencing. NGS provides a significant statistical base that enables motif analysis, statistics on positional residue depletion/enrichment, and data analysis to suppress false-positive sequences from amplification bias. The selected sequences are employed as water-based primers for PP-metal adhesion to condition PP surfaces and increase adhesive strength by 100% relative to nonprimed PP. KW - Polymers KW - Polypropylene KW - Glue KW - Plastics KW - Surface Activation KW - Primer KW - Peptide Library KW - Epoxy KW - Solid-binding Peptides KW - Functionalization KW - Polymer-binding Peptides KW - Adhesion KW - Material-binding Peptides KW - Adhesives PY - 2020 DO - https://doi.org/10.1021/jacs.0c03482 SN - 0002-7863 SN - 1520-5126 VL - 142 IS - 24 SP - 10624 EP - 10628 PB - ACS CY - Washington, DC, USA AN - OPUS4-51123 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -