Elisabeth Eidenberger

Neutrons and Synchrotron Radiation in Engineering Materials Science

PART I: GENERAL MICROSTRUCTURE AND PROPERTIES OF ENGINEERING MATERIALS INTERNAL STRESSES IN ENGINEERING MATERIALS TEXTURE AND TEXTURE ANALYSIS IN ENGINEERING MATERIALS PHYSICAL PROPERTIES OF PHOTONS AND NEUTRONS RADIATION SOURCES GENERATION AND PROPERTIES OF NEUTRONS PRODUCTION AND PROPERTIES OF SYNCHROTRON RADIATION PART II: METHODS INTRODUCTION TO DIFFRACTION METHODS FOR INTERNAL STRESS ANALYSES STRESS ANALYSIS BY ANGLE-DISPENSIVE NEUTRON DIFFRACTION STRESS ANALYSIS BY ENERGY-DISPERSIVE NEUTRON DIFFRACTION RESIDUAL STRESS ANALYSIS BY MONOCHROMATIC HIGH-ENERGY X-RAYS RESIDUAL STRESS ANALYSIS BY WHITE HIGH ENERGY X-RAYS REFLECTION MODE TRANSMISSION MODE DIFFRACTION IMAGING FOR MICROSTRUCTURE ANALYSIS BASICS OF SMALL-ANGLE SCATTERING METHODS SMALL-ANGLE NEUTRON SCATTERING DECOMPOSITION KINETICS IN COPPER-COBALT ALLOY SYSTEMS: APPLICATIONS OF SMALL-ANGLE X-RAY SCATTERING New Developments in Neutron Tomography NEUTRON AND SYNCHROTRON -RADIATION-BASED IMAGING FOR APPLICATIONS IN MATERIALS SCIENCE - FROM MACRO- TO NANOTOMOGRAPHY mu-TOMOGRAPHY OF ENGINEERING MATERIALS DIFFRACTION ENHANCED IMAGING PART III: NEW AND EMERGING METHODS 3D X-RAY DIFFRACTION MICROSCOPE 3D MICRON-RESOLUTION LAUE DIFFRACTION QUANTITATIVE ANALYSIS OF THREE-DIMENSIONAL PLASTICS STRAIN FIELD USING MARKERS AND X-RAY ABSORPTION TOMOGRAPHY COMBINED DIFFRACTION AND TOMOGRAPHY PART IV: INDUSTRIAL APPLICATIONS DIFFRACTION-BASED RESIDUAL STRESS ANALYSIS APPLIED TO PROBLEMS IN THE AIRCRAFT INDUSTRY OPTIMIZATION OF RESIDUAL STRESSES IN CRANKHAFTS

Characteristics of an optimized active metal cast joint between copper and C/C

In this paper, an optimized active metal cast copper to carbon composite (C/C) joint is examined. Mechanical characterization by means of shear and tensile tests as well as fracture toughness measurements at ambient temperature are employed, which show that the obtained values are above those of the reference joint that has been used so far. The phases occurring at the interface region and the fracture surface of the optimized joint are investigated in detail to explain the improved mechanical behaviour. The composition and the morphology at the interface region are analysed by means of scanning electron microscopy. In addition, the crack path is analysed by stereomicroscopy. The improved properties can be explained by the circumstance that the fracture of the optimized joint is not restricted to the interface between the occurring carbide and the C/C but changes between C/C, the carbide to C/C interface and the copper, depending on the local structure in the C/C composite.

Critical consideration of precipitate analysis of Fe-1 at.% Cu using atom probe and small-angle neutron scattering.

An Fe-1 at.% Cu model alloy was examined by atom probe (3DAP) and small-angle neutron scattering (SANS) to verify the accordance of the gained results. The Fe-Cu alloy was heat-treated for various times at 500°C, forming Cu-rich precipitates within the Fe matrix. The chemical compositions of the precipitates and matrix found by 3DAP were used to calculate the magnetic scattering contrast. Additionally, a magnetic moment of the precipitates that contain a significant amount of Fe was taken into account for the calculation of magnetic scattering contrast. This in turn is used for the evaluation of the magnetic scattering curves gained by SANS. Both the 3DAP data as well as the scattering curves were analyzed with regard to radius, number density, and volume fraction of the precipitates as a function of aging time. The results yielded by both techniques are in good agreement and correspond to the development of the hardness of the alloy. Minor differences can be related to the cluster search algorithm used for the analysis of the 3DAP data as well as Fe overestimation based on different field phases.

In situ small-angle neutron scattering study of the early stages of precipitation in Fe-25at% Co-9at% Mo and Fe-1at% Cu at 500 °C

The early stages of precipitate formation in Fe-25at% Co-9at% Mo at 500 °C was investigated by in situ small-angle neutron scattering (SANS). The ratio of magnetic to nuclear SANS intensity, which depends on the precipitate composition, and the precipitate sizes were analyzed. The results suggest that in the Fe-Co-Mo alloy an initial stage of precipitate formation with strong compositional changes is completed after 150 s, when the full magnetic signal is established. For comparison, the well-known nucleation and growth reaction in Fe-1at% Cu was studied. Differences in the growth rate of the mean size of the developing structures could be distinguished in the two investigated alloys. While in the Fe-Co-Mo alloy the precipitate structures grow with t0.15 to t0.21, the mean precipitate radius in the Fe-Cu alloy grows with t0.40 in the observed time interval.

Mikrostruktur einer C/C-Cu Verbindung für Erste-Wand-Komponenten des ITER

Kurzfassung Im Rahmen der vorliegenden Arbeit wurde eine von der Firma PLANSEE entwickelte C/C-Cu-Verbindung hinsichtlich der auftretenden Mikrostruktur der Grenzfläche untersucht. Die Kenntnis des Aufbaus der Verbindungszone ist essentiell für das Verständnis des mechanischen Verhaltens der Verbindung. Zum einen wurden daher die auftretenden Phasen mittels Röntgenspektroskopie analysiert, zum anderen wurde die Morphologie des Grenzflächenbereichs an Querschliffen im Rasterelektronenmikroskop untersucht. Es wurden dabei mit unterschiedlichen Herstellparametern gefertigte Proben analysiert. Es zeigt sich, dass abhängig vom Si-Gehalt, deutlich unterscheidbare Mikrostrukturen in der Verbindungszone C/C-Cu entstehen, die in weiterer Folge auch für das unterschiedliche mechanische Verhalten verantwortlich sind.