A5031040648- Nuclear Physics and Applications
- High-pressure geophysics and materials
- Non-Destructive Testing Techniques
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- X-ray Diffraction in Crystallography
- Nuclear reactor physics and engineering
- Additive Manufacturing Materials and Processes
- Hydrogen embrittlement and corrosion behaviors in metals
- Nuclear Materials and Properties
- Astro and Planetary Science
- Microstructure and Mechanical Properties of Steels
- Welding Techniques and Residual Stresses
- Planetary Science and Exploration
- Machine Learning in Materials Science
- Quantum, superfluid, helium dynamics
- Elasticity and Material Modeling
- Geophysical Methods and Applications
- Additive Manufacturing and 3D Printing Technologies
- Drilling and Well Engineering
- Particle Detector Development and Performance
- Thermography and Photoacoustic Techniques
- Ultrasonics and Acoustic Wave Propagation
- Advancements in Battery Materials
- High-Velocity Impact and Material Behavior
European Spallation Source
2016-2025
Czech Academy of Sciences, Nuclear Physics Institute
2018-2024
Czech Academy of Sciences
2022
Helmholtz-Zentrum Berlin für Materialien und Energie
2011-2018
University of Tennessee at Knoxville
2009-2017
An overview is provided of the 15 neutron beam instruments making up initial instrument suite European Spallation Source (ESS), and being made available to user community. The ESS source consists a high-power accelerator target station, providing unique long-pulse time structure slow neutrons. design considerations behind structure, moderator geometry layout are presented. 15-instrument two small-angle instruments, reflectometers, an imaging beamline, single-crystal diffractometers; one for...
Nondestructive 3D mapping of crystallographic phases is introduced providing distribution phase fractions within the bulk (centimeter range) samples with micrometer-scale resolution. The novel neutron tomography based technique overcomes critical limitations existing techniques and offers a wide range potential applications. It demonstrated for steel exhibiting transformation after being subjected to tensile torsional deformation. As service our authors readers, this journal provides...
The construction of the new neutron imaging instrument at BER-2 research reactor Helmholtz-Zentrum Berlin has greatly increased potential facility. redesign facility included improvements extraction and transportation systems, more effective shielding, innovative instrumentation. cold flux guide exit was by than one order magnitude, which allowed for an implementation methods that require monochromatic or polarized beams, thus enabling exploitation nonconventional contrast mechanisms such as...
Wavelength selective neutron radiography at a cold reactor source was used to measure strain and determine (residual) stresses in steel sample under plane stress conditions. We present new technique that uses an energy-resolved imaging system based on double crystal monochromator is equipped with specially developed (in situ) biaxial load frame perform Bragg edge transmission imaging. The provides viewing area of 7 cm by spatial resolution the order ∼ 100 μm. stress-induced shifts...
This paper describes non-destructive three-dimensional (3D) mapping of crystallographic phase distributions within the bulk (centimeter range) samples with micrometer-scale resolution. The technique leverages diffraction contrast due to Bragg scattering and large penetration power neutrons through high-atomic-number-element-based structural materials. Our tomographic approach overcomes critical limitations existing techniques by allowing spatially resolved in offers a wide range potential...
Abstract Energy‐efficient, safe, and reliable Li‐ion batteries (LIBs) are required for a wide range of applications. The introduction ultra‐thick graphite anodes, desired high energy densities, meets limitations in internal electrode transport properties, leading to detrimental consequences. Yet, there is lack experimental tools capable providing complete view local processes. Here, multi‐modal operando measurement approach introduced, enabling quantitative spatio‐temporal observations Li...
Abstract This study utilizes advanced 3D imaging techniques, combining X-ray and neutron tomography, to investigate the hydromechanical evolution of Idaho Gray sandstone during coupled triaxial permeability tests. The analysis involved correlating mechanical hydraulic bulk measurements, porosity fields, strain fields derived from Digital Volume Correlation fluid speed time series tomograms. experimental approach provides an improved understanding relationship between volume active pores...
Conventional neutron imaging utilizes the beam attenuation caused by scattering and absorption through materials constituting an object in order to investigate its macroscopic inner structure. Small angle has basically no impact on such images under geometrical conditions applied. Nevertheless, recent years different experimental methods have been developed imaging, which enable not only generate contrast based neutrons scattered very small angles, but map quantify with spatial resolution of...
Abstract Cold neutrons have a wavelength that is in the same range as lattice spacings of most polycrystalline metallic materials. Imaging such materials with monochromatic cold different wavelengths provides unique contrast due to coherent Bragg scattering. Additionally, spectral positions edges can be mapped for each point an image by using transmission data corresponding scans. We present investigations welded components energy-selective neutron radiography around specific Bragg-edges...
Residual stress/strain and microstructure used in additively manufactured material are strongly dependent on process parameter combination. With the aim to better understand correlate parameters electron beam melting (EBM) of Ti-6Al-4V with resulting phase distributions residual stress/strains, extensive experimental work has been performed. A large number polycrystalline specimens were produced different optimized EBM combinations. These post-sequentially studied by using high-energy X-ray...
We report on measured neutron cross section data for super-cooled water and ice by time-of-flight (TOF) transmission imaging. In particular, we demonstrate the use of high duty cycle (HDC)-TOF measurements to determine local aggregate state with spatial resolution, exploiting dependence mobility hydrogen atoms long wavelengths (>4 Å). While one can envision many different applications this method, example is provide insights into freezing mechanism during start-up polymer electrolyte...
We present spectroscopic neutron imaging (SNI), a bridge between and scattering techniques, for the analysis of hydrogenated molecules in lithium-ion cells. The information CHn-based organic solvents electrolytes was mapped two-dimensional space by investigating wavelength-dependent property hydrogen atoms through time-of-flight imaging. Our investigation demonstrates novel approach to detect physical chemical changes liquids, which extends, but not limits, use SNI relevant applications...
This paper presents an in-situ observation, using neutron imaging, of delayed crack propagation in a high-strength martensitic steel specimen. Delayed cracking is believed to be caused by hydrogen embrittlement occurring due the slow diffusion and accumulation ahead front, causing decreased ductility eventual under constant load. The experiment involved mechanical loading single-edge-notch bend specimen while submerged electrolyte solution (H2O + 3.5% NaCl) cathodic polarization facilitate...
Combined three-dimensional (3D) mapping of (micro-)structures with elemental and crystalline phase variations is significant importance for the characterization materials. Neutron wavelength selective imaging a spectral technique that exploits unique contrast differences e.g. dissimilar elemental, isotope, or compositions, has particular advantage being applicable to sample volumes on meso- macroscale. While mostly applied as radiography (2D) so far, we herein report extension tomography...
A systematic study has been carried out to investigate the neutron transmission signal as a function of sample tem-per-ature. In particular, experimentally de-ter-mined wavelength-dependent attenuation spectra for martensitic steel at tem-per-atures ranging from 21 700°C are com-pared with simulated data. theoretical description that includes Debye-Waller factor in order describe tem-per-ature influence on cross sections was im-plemented nxsPlotter software and used simulations. The analysis...
We herein report on using a compact and low cost scintillator-camera based neutron detection system for quantitative time-of-flight imaging applications. While powerful pulsed sources emerge enable unprecedented scientific achievements, one bottleneck is the availability of suitable detectors that provide high count- frame- rate capabilities. For applications achievable spatial resolution/pixel size obviously another key characteristic. major effort was so far directed towards development...