Metastable Phase Formation in Undercooled Nd-Fe-B Alloys Investigated by In Situ Diffraction Using Synchrotron Radiation

2006 ◽  
Vol 508 ◽  
pp. 81-86 ◽  
Author(s):  
Joern Strohmenger ◽  
Thomas Volkmann ◽  
J.R. Gao ◽  
Dieter M. Herlach
Keyword(s):  
Synchrotron Radiation ◽  
Metastable Phase ◽  
European Synchrotron Radiation Facility ◽  
Wide Composition Range ◽  
Short Period ◽  
Metastable Phase Formation ◽  
Undercooled Melt ◽  
Electromagnetically Levitated ◽  
In Situ Diffraction

Diffraction experiments on electromagnetically levitated Nd-Fe-B alloys during solidification of the undercooled melt have been performed at the European Synchrotron Radiation Facility (ESRF). By using high intensity synchrotron radiation complete diffraction spectra could be detected within a short period of some seconds thus enabling the observation of metastable solidification products that exhibits a limited lifetime. A metastable phase that crystallizes in wide composition range and that initiates the solidification of the stable Nd2Fe14B1-phase (φ-phase) have been observed.

scholarly journals A large-solid-angle X-ray Raman scattering spectrometer at ID20 of the European Synchrotron Radiation Facility

2017 ◽  
Vol 24 (2) ◽  
pp. 521-530 ◽  
Author(s):  
S. Huotari ◽  
Ch. J. Sahle ◽  
Ch. Henriquet ◽  
A. Al-Zein ◽  
K. Martel ◽  
...  
Keyword(s):  
Synchrotron Radiation ◽  
Raman Scattering ◽  
Solid Angle ◽  
European Synchrotron Radiation Facility ◽  
Electronic Excitations ◽  
Raman Scattering Spectroscopy ◽  
X Ray ◽  
Area Detector ◽  
Spectroscopic Tool

An end-station for X-ray Raman scattering spectroscopy at beamline ID20 of the European Synchrotron Radiation Facility is described. This end-station is dedicated to the study of shallow core electronic excitations using non-resonant inelastic X-ray scattering. The spectrometer has 72 spherically bent analyzer crystals arranged in six modular groups of 12 analyzer crystals each for a combined maximum flexibility and large solid angle of detection. Each of the six analyzer modules houses one pixelated area detector allowing for X-ray Raman scattering based imaging and efficient separation of the desired signal from the sample and spurious scattering from the often used complicated sample environments. This new end-station provides an unprecedented instrument for X-ray Raman scattering, which is a spectroscopic tool of great interest for the study of low-energy X-ray absorption spectra in materials under in situ conditions, such as in operando batteries and fuel cells, in situ catalytic reactions, and extreme pressure and temperature conditions.

Metastable Phase Formation in the Y-TI System by Ion Mixing

1991 ◽  
Vol 235 ◽  
Author(s):  
S. L. Lai ◽  
Z. J. Zhang ◽  
J. R. Ding ◽  
B. X. Liu
Keyword(s):  
Metastable Phase ◽  
Heat Of Formation ◽  
Crystalline Lattice ◽  
Vacuum Furnace ◽  
Multilayered Films ◽  
Glass Forming ◽  
Transmission Electron ◽  
Metastable Phase Formation ◽  
First Time

ABSTRACTAmorphization behavior was studied for the Y-Ti system, which has rather positive heat of formation being around + 22 kJ/mol, by room temperature 360 keV xenon ion mixing of YxTi100−xmultilayered films to various doses, ranging from 7×1014 to 1×1016 xe/cm2 Single and uniform amorphous phase was obtained in a narrow composition region, i.e. x=65 to 75, after ion mixing to the relevant doses. Moreover, a metastable fee crystalline Y-Ti phase was observed, for the first time, in this system. The crystalline lattice constant of the metastable phase was determined to be 4.012 Å. The re-crystallization temperature of the formed amorphous alloy was found out to be 600°C by in situ transmission electron microscope annealing as well as by vacuum furnace experiments. Possible interpretation is also discussed by comparing the experimental results with those proposed models for predicting glass forming ability.

Measurement of Stress in Phosphated-Iron Oxide Layers by In-Situ Diffraction of Synchrotron Radiation

2002 ◽  
Vol 404-407 ◽  
pp. 809-816 ◽  
Author(s):  
Benoit Panicaud ◽  
Pierre Olivier Renault ◽  
Jean Luc Grosseau-Poussard ◽  
J.F. Dinhut ◽  
D. Thiaudière ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Synchrotron Radiation ◽  
Oxide Layers ◽  
In Situ Diffraction

scholarly journals Evolution of structure and local magnetic fields during crystallization of HITPERM glassy alloys studied by in situ diffraction and nuclear forward scattering of synchrotron radiation

2015 ◽  
Vol 17 (42) ◽  
pp. 28239-28249 ◽  
Author(s):  
Marcel Miglierini ◽  
Márius Pavlovič ◽  
Vít Procházka ◽  
Tomáš Hatala ◽  
Gerhard Schumacher ◽  
...  
Keyword(s):  
Synchrotron Radiation ◽  
Metallic Glasses ◽  
Local Structure ◽  
Hyperfine Interactions ◽  
Nuclear Forward Scattering ◽  
Glassy Alloys ◽  
Evolution Of Structure ◽  
Local Magnetic Fields ◽  
In Situ Diffraction

In situ transformation of local structure and hyperfine interactions are simultaneously followed in real time during temperature annealing of metallic glasses.

Thermal Stability of Retained Austenite in Low Alloyed TRIP-Steel Determined by High Energy Synchrotron Radiation

2013 ◽  
Vol 772 ◽  
pp. 129-133
Author(s):  
Stefan Brauser ◽  
Arne Kromm ◽  
Eitan Dabah ◽  
Thomas Kannengiesser ◽  
Michael Rethmeier
Keyword(s):  
Synchrotron Radiation ◽  
High Energy ◽  
Heating Process ◽  
Austenitic Phase ◽  
Trip Steels ◽  
The Stability ◽  
In Situ Diffraction ◽  
Kinetics Of ◽  
Thermal Stability Of

TRIP-steels offer a good combination between strength and ductility. Therefore TRIP-steels are widely used in the automobile industries. The aim of this work is to study the stability of involved phases during heating and to identify the kinetics of the occuring phase transformations. For that purpose, in-situ diffraction measurements, using high energy synchrotron radiation were conducted. The analysis revealed the decomposition of the metastable austenitic phase into carbide and ferrite along the heating process and the regeneration of the austenite by further heating of the sample.

scholarly journals Simultaneous X-ray radiography and diffraction topography imaging applied to silicon for defect analysis during melting and crystallization

2019 ◽  
Vol 52 (6) ◽  
pp. 1312-1320 ◽  
Author(s):  
Maike Becker ◽  
Gabrielle Regula ◽  
Guillaume Reinhart ◽  
Elodie Boller ◽  
Jean-Paul Valade ◽  
...  
Keyword(s):  
Synchrotron Radiation ◽  
Grain Boundaries ◽  
Growth Process ◽  
Defect Formation ◽  
Simultaneous Recording ◽  
European Synchrotron Radiation Facility ◽  
Crystal Defects ◽  
Structural Defects ◽  
X Ray

One of the key issues to be resolved to improve the performance of silicon solar cells is to reduce crystalline defect formation and propagation during the growth-process fabrication step. For this purpose, the generation of structural defects such as grain boundaries and dislocations in silicon must be understood and characterized. Here, in situ X-ray diffraction imaging, historically named topography, is combined with radiography imaging to analyse the development of crystal defects before, during and after crystallization. Two individual indirect detector systems are implemented to record simultaneously the crystal structure (topographs) and the solid–liquid morphology evolution (radiographs) at high temperature. This allows for a complete synchronization of the images and for an increased image acquisition rate compared with previous studies that used X-ray sensitive films to record the topographs. The experiments are performed with X-ray synchrotron radiation at beamline ID19 at the European Synchrotron Radiation Facility. In situ observations of the heating, melting, solidification and holding stages of silicon samples are presented, to demonstrate that with the upgraded setup detailed investigations of time-dependent phenomena are now possible. The motion of dislocations is recorded throughout the experiment, so that their interaction with grain boundaries and their multiplication through the activation of Frank–Read sources can be observed. Moreover, the capability to record with two camera-based detectors allows for the study of the relationship between strain distribution, twinning and nucleation events. In conclusion, the simultaneous recording of topographs and radiographs has great potential for further detailed investigations of the interaction and generation of grains and defects that influence the growth process and the final crystalline structure in silicon and other crystalline materials.

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