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Materials Research (material + research)

Distribution by Scientific Domains
Polymers and Materials Science66%

Selected Abstracts

Zerstörungsfreie Ortung von Fehlstellen und Inhomogenitäten in Bauteilen mit der Impuls-Thermografie

BAUTECHNIK, Issue 10 2004
Ralf Arndt Dipl.-Ing.
Im Rahmen eines von der Deutschen Forschungsgemeinschaft geförderten Forschungsvorhabens wird von der Bundesanstalt für Materialforschung und -prüfung (BAM) und der Technischen Universität Berlin (TUB) die Anwendung der Impuls-Thermografie zur zerstörungsfreien Prüfung von Bauteilen und Bauwerken weiterentwickelt. Zu diesem Zweck werden Messungen zu verschiedenen baupraktischen Fragestellungen durchgeführt. Die Bauteiloberflächen werden mit einer Wärmequelle, die dem Prüfproblem angepaßt ist, erwärmt. Der daran anschließende Abkühlungsvorgang wird mit einer Infrarotkamera beobachtet und aufgenommen. Die anschließende Auswertung der gespeicherten Daten wird im Zeitbereich mittels numerischer Verfahren und im Frequenzbereich mittels Puls-Phasen-Thermografie durchgeführt. Die Puls-Phasen-Thermografie führt insbesondere zu einer praxisrelevanten Reduzierung des Störeinflusses von Oberflächeninhomogenitäten und ungleichmäßiger Erwärmung. Non-destructive detection of voids and inhomogeneities in building structures using impulse thermography. In the frame of a research project funded by the "Deutsche Forschungsgemeinschaft" the application of impulse thermography for the non-destructive testing of building components and buildings is further developed by the Federal Institute for Material Research and Testing (BAM) and the Technical University of Berlin (TUB). To this aim measurements to several practical problems of civil engineering were carried out. The inspected specimen is pulse heated according to the problem. The following cooling down process is recorded with an infrared camera. The transient behaviour is afterwards analysed by numerical methods in the time domain and by means of Pulse-Phase-Thermography in the frequency domain. Pulse-Phase-Thermography in particular reduces the influence of inhomogeneous surfaces and non-uniform heating on thermographic measurements. [source]

Synchrotron-Based Micro-CT and Refraction-Enhanced Micro-CT for Non-Destructive Materials Characterisation,

ADVANCED ENGINEERING MATERIALS, Issue 6 2009
Bernd R. Müller
Abstract X-ray computed tomography is an important tool for non-destructively evaluating the 3-D microstructure of modern materials. To resolve material structures in the micrometer range and below, high brilliance synchrotron radiation has to be used. The Federal Institute for Materials Research and Testing (BAM) has built up an imaging setup for micro-tomography and -radiography (BAMline) at the Berliner storage ring for synchrotron radiation (BESSY). In computed tomography, the contrast at interfaces within heterogeneous materials can be strongly amplified by effects related to X-ray refraction. Such effects are especially useful for materials of low absorption or mixed phases showing similar X-ray absorption properties that produce low contrast. The technique is based on ultra-small-angle scattering by microstructural elements causing phase-related effects, such as refraction and total reflection. The extraordinary contrast of inner surfaces is far beyond absorption effects. Crack orientation and fibre/matrix debonding in plastics, polymers, ceramics and metal-matrix-composites after cyclic loading and hydro-thermal aging can be visualized. In most cases, the investigated inner surface and interface structures correlate to mechanical properties. The technique is an alternative to other attempts on raising the spatial resolution of CT machines. [source]

Materials and Corrosion 9/2010

MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 9 2010
Article first published online: 2 SEP 2010
Cover: Metallic structure of X1NiCrMoCu32-28-7 (UNS N08031, alloy 31, 1.4562) welded with SG-NiCr23Mo16 (FM 59, 2.4607) after 4 weeks in the vapor phase of nitrating acid (mixture of 66 % HNO3, 34 % H2SO4) at 55 °C. No further treatment of the surface was made. Corrosion behavior was investigated at BAM, the Federal Institute for Materials Research and Testing, in order to extend the BAM-List, where the suitability of materials for transport tanks carrying Dangerous Goods is evaluated. More detailed information can be found in: R. Bäßler. M. Weltschev, H. Alves, M. Langer, Corrosion Resistance of Alloy 31 and 59 in Highly Corrosive Dangerous Goods, Proceedings NACE International Corrosion Conference 2010 San Antonio, paper 10340. [source]

Materials and Corrosion 8/2010

MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 8 2010
Article first published online: 2 AUG 2010
Cover: Metallic structure of X1NiCrMoCu32-28-7 (UNS N08031, alloy 31, 1.4562) welded with SG-NiCr23Mo16 (FM 59, 2.4607) after 4 weeks in the vapor phase of nitrating acid (mixture of 66 % HNO3, 34 % H2SO4) at 55 °C. No further treatment of the surface was made. Corrosion behavior was investigated at BAM, the Federal Institute for Materials Research and Testing, in order to extend the BAM-List, where the suitability of materials for transport tanks carrying Dangerous Goods is evaluated. More detailed information can be found in: R. Bäßler. M. Weltschev, H. Alves, M. Langer, Corrosion Resistance of Alloy 31 and 59 in Highly Corrosive Dangerous Goods, Proceedings NACE International Corrosion Conference 2010 San Antonio, paper 10340. [source]

Materials and Corrosion 7/2010

MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 7 2010
Article first published online: 19 JUL 2010
Cover: Metallic structure of X1NiCrMoCu32?28?7 (UNS N08031, alloy 31, 1.4562) welded with SG-NiCr23Mo16 (FM 59, 2.4607) after 4 weeks in the vapor phase of nitrating acid (mixture of 66 % HNO3, 34 % H2SO4) at 55 °C. No further treatment of the surface was made. Corrosion behavior was investigated at BAM, the Federal Institute for Materials Research and Testing, in order to extend the BAM-List, where the suitability of materials for transport tanks carrying Dangerous Goods is evaluated. More detailed information can be found in: R. Bäßler. M. Weltschev, H. Alves, M. Langer, Corrosion Resistance of Alloy 31 and 59 in Highly Corrosive Dangerous Goods, Proceedings NACE International Corrosion Conference 2010 San Antonio, paper 10340. [source]

Applications of Free-Electron Lasers in the Biological and Material Sciences,

PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2005
G. S. Edwards
ABSTRACT Free-Electron Lasers (FELs) collectively operate from the terahertz through the ultraviolet range and via intracavity Compton backscattering into the X-ray and gamma-ray regimes. FELs are continuously tunable and can provide optical powers, pulse structures and polarizations that are not matched by conventional lasers. Representative research in the biological and biomedical sciences and condensed matter and material research are described to illustrate the breadth and impact of FEL applications. These include terahertz dynamics in materials far from equilibrium, infrared nonlinear vibrational spectroscopy to investigate dynamical processes in condensed-phase systems, infrared resonant-enhanced multiphoton ionization for gas-phase spectroscopy and spectrometry, infrared matrix-assisted laser-desorption-ionization and infrared matrix-assisted pulsed laser evaporation for analysis and processing of organic materials, human neurosurgery and ophthalmic surgery using a medical infrared FEL and ultraviolet photoemission electron microscopy for nanoscale characterization of materials and nanoscale phenomena. The ongoing development of ultraviolet and X-ray FELs are discussed in terms of future opportunities for applications research. [source]