Simultaneous X-ray radioscopy/tomography and energy-dispersive diffraction applied to liquid aluminium alloy foams

2018 ◽  
Vol 25 (6) ◽  
pp. 1790-1796 ◽  
Author(s):  
Catalina Jiménez ◽  
Marlen Paeplow ◽  
Paul H. Kamm ◽  
Tillmann R. Neu ◽  
Manuela Klaus ◽  
...  
Keyword(s):  
Aluminium Alloy ◽  
High Speed ◽  
Metal Foam ◽  
Two Dimensions ◽  
Three Dimensions ◽  
X Ray Diffraction ◽  
Liquid Aluminium ◽  
X Ray ◽  
Foaming Process ◽  
X Ray Imaging

High-speed X-ray imaging in two dimensions (radioscopy) and three dimensions (tomography) is combined with fast X-ray diffraction in a new experimental setup at the synchrotron radiation source BESSY II. It allows forin situstudies of time-dependent phenomena in complex systems. As a first application, the foaming process of an aluminium alloy was studied in three different experiments. Radioscopy, optical expansion measurements and diffraction were used to correlate the change of foam morphology to the various phases formed during heating of an AlMg15Cu10 alloy to 620°C in the first experiment. Radioscopy was then replaced by tomography. Acquiring tomograms and diffraction data at 2 Hz allows even more details of foam evolution to be captured, for example, bubble size distribution. In a third experiment, 4 Hz tomography yields dynamic insights into fast phenomena in evolving metal foam.

scholarly journals Electron crystallography: imaging and single-crystal diffraction from powders

2007 ◽  
Vol 64 (1) ◽  
pp. 149-160 ◽  
Author(s):  
Xiaodong Zou ◽  
Sven Hovmöller
Keyword(s):  
Three Dimensional ◽  
Two Dimensions ◽  
Three Dimensions ◽  
Crystallographic Structure ◽  
X Ray Diffraction ◽  
Electron Crystallography ◽  
X Ray ◽  
X Ray Crystallography ◽  
Dimensional Reconstruction ◽  
Recent Developments

The study of crystals at atomic level by electrons – electron crystallography – is an important complement to X-ray crystallography. There are two main advantages of structure determinations by electron crystallography compared to X-ray diffraction: (i) crystals millions of times smaller than those needed for X-ray diffraction can be studied and (ii) the phases of the crystallographic structure factors, which are lost in X-ray diffraction, are present in transmission-electron-microscopy (TEM) images. In this paper, some recent developments of electron crystallography and its applications, mainly on inorganic crystals, are shown. Crystal structures can be solved to atomic resolution in two dimensions as well as in three dimensions from both TEM images and electron diffraction. Different techniques developed for electron crystallography, including three-dimensional reconstruction, the electron precession technique and ultrafast electron crystallography, are reviewed. Examples of electron-crystallography applications are given. There is in principle no limitation to the complexity of the structures that can be solved by electron crystallography.

scholarly journals X-ray Determination of Compressive Residual Stresses in Spring Steel Generated by High-Speed Water Quenching

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1154
Author(s):  
Diego E. Lozano ◽  
George E. Totten ◽  
Yaneth Bedolla-Gil ◽  
Martha Guerrero-Mata ◽  
Marcel Carpio ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Residual Stresses ◽  
High Speed ◽  
Spring Steel ◽  
X Ray Diffraction ◽  
Laboratory Equipment ◽  
X Ray ◽  
Water Chamber ◽  
Hardened Case ◽  
Compressive Residual Stresses

Automotive components manufacturers use the 5160 steel in leaf and coil springs. The industrial heat treatment process consists in austenitizing followed by the oil quenching and tempering process. Typically, compressive residual stresses are induced by shot peening on the surface of automotive springs to bestow compressive residual stresses that improve the fatigue resistance and increase the service life of the parts after heat treatment. In this work, a high-speed quenching was used to achieve compressive residual stresses on the surface of AISI/SAE 5160 steel samples by producing high thermal gradients and interrupting the cooling in order to generate a case-core microstructure. A special laboratory equipment was designed and built, which uses water as the quenching media in a high-speed water chamber. The severity of the cooling was characterized with embedded thermocouples to obtain the cooling curves at different depths from the surface. Samples were cooled for various times to produce different hardened case depths. The microstructure of specimens was observed with a scanning electron microscope (SEM). X-ray diffraction (XRD) was used to estimate the magnitude of residual stresses on the surface of the specimens. Compressive residual stresses at the surface and sub-surface of about −700 MPa were obtained.

scholarly journals Fingerprinting shock-induced deformations via diffraction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Avanish Mishra ◽  
Cody Kunka ◽  
Marco J. Echeverria ◽  
Rémi Dingreville ◽  
Avinash M. Dongare
Keyword(s):  
High Speed ◽  
Shock Loading ◽  
Dislocation Slip ◽  
Line Profiles ◽  
X Ray Diffraction ◽  
Final State ◽  
X Ray ◽  
Shock Testing ◽  
Local Pressures ◽  
Deformation Modes

AbstractDuring the various stages of shock loading, many transient modes of deformation can activate and deactivate to affect the final state of a material. In order to fundamentally understand and optimize a shock response, researchers seek the ability to probe these modes in real-time and measure the microstructural evolutions with nanoscale resolution. Neither post-mortem analysis on recovered samples nor continuum-based methods during shock testing meet both requirements. High-speed diffraction offers a solution, but the interpretation of diffractograms suffers numerous debates and uncertainties. By atomistically simulating the shock, X-ray diffraction, and electron diffraction of three representative BCC and FCC metallic systems, we systematically isolated the characteristic fingerprints of salient deformation modes, such as dislocation slip (stacking faults), deformation twinning, and phase transformation as observed in experimental diffractograms. This study demonstrates how to use simulated diffractograms to connect the contributions from concurrent deformation modes to the evolutions of both 1D line profiles and 2D patterns for diffractograms from single crystals. Harnessing these fingerprints alongside information on local pressures and plasticity contributions facilitate the interpretation of shock experiments with cutting-edge resolution in both space and time.

Simulation and Experiment on the Residual Stress in Super-High Speed Grinding

2010 ◽  
Vol 135 ◽  
pp. 238-242
Author(s):  
Yue Ming Liu ◽  
Ya Dong Gong ◽  
Wei Ding ◽  
Ting Chao Han
Keyword(s):  
Residual Stress ◽  
High Speed ◽  
Element Model ◽  
Residual Stress Distribution ◽  
X Ray Diffraction ◽  
Machined Surface ◽  
X Ray ◽  
High Speed Grinding ◽  
Simulation And Experiment ◽  
Cylindrical Workpiece

In this paper, effective finite element model have been developed to simulation the plastic deformation cutting in the process for a single particle via the software of ABAQUS, observing the residual stress distribution in the machined surface, the experiment of grinding cylindrical workpiece has been brought in the test of super-high speed grinding, researching the residual stress under the machined surface by the method of X-ray diffraction, which can explore the different stresses from different super-high speed in actual, and help to analyze the means of reducing the residual stresses in theory.

scholarly journals X-ray imaging of silicon die within fully packaged semiconductor devices

2021 ◽  
pp. 1-7
Author(s):  
Brian K. Tanner ◽  
Patrick J. McNally ◽  
Andreas N. Danilewsky
Keyword(s):  
Synchrotron Radiation ◽  
Feasibility Studies ◽  
Monochromatic Radiation ◽  
X Ray Diffraction ◽  
Divergent Beam ◽  
X Ray ◽  
X Ray Imaging ◽  
Setting Process ◽  
Diffraction Imaging ◽  
Lattice Planes

X-ray diffraction imaging (XRDI) (topography) measurements of silicon die warpage within fully packaged commercial quad-flat no-lead devices are described. Using synchrotron radiation, it has been shown that the tilt of the lattice planes in the Analog Devices AD9253 die initially falls, but after 100 °C, it rises again. The twist across the die wafer falls linearly with an increase in temperature. At 200 °C, the tilt varies approximately linearly with position, that is, displacement varies quadratically along the die. The warpage is approximately reversible on cooling, suggesting that it has a simple paraboloidal form prior to encapsulation; the complex tilt and twisting result from the polymer setting process. Feasibility studies are reported, which demonstrate that a divergent beam and quasi-monochromatic radiation from a sealed X-ray tube can be used to perform warpage measurements by XRDI in the laboratory. Existing tools have limitations because of the geometry of the X-ray optics, resulting in applicability only to simple warpage structures. The necessary modifications required for use in situations of complex warpage, for example, in multiple die interconnected packages are specified.

UFO — a scalable platform for high-speed synchrotron X-ray imaging

2016 ◽  
Author(s):  
Andreas Kopmann ◽  
Suren Chilingaryan ◽  
Matthias Vogelgesang ◽  
Timo Dritschler ◽  
Andrey Shkarin ◽  
...  
Keyword(s):  
High Speed ◽  
X Ray ◽  
X Ray Imaging

syris: a flexible and efficient framework for X-ray imaging experiments simulation

2017 ◽  
Vol 24 (6) ◽  
pp. 1283-1295 ◽  
Author(s):  
Tomáš Faragó ◽  
Petr Mikulík ◽  
Alexey Ershov ◽  
Matthias Vogelgesang ◽  
Daniel Hänschke ◽  
...  
Keyword(s):  
Motion Estimation ◽  
Data Processing ◽  
Graphics Processing Units ◽  
High Speed ◽  
Real Data ◽  
Estimation Accuracy ◽  
Processing Parameter ◽  
X Ray ◽  
X Ray Imaging ◽  
Imaging Conditions

An open-source framework for conducting a broad range of virtual X-ray imaging experiments,syris, is presented. The simulated wavefield created by a source propagates through an arbitrary number of objects until it reaches a detector. The objects in the light path and the source are time-dependent, which enables simulations of dynamic experiments,e.g.four-dimensional time-resolved tomography and laminography. The high-level interface ofsyrisis written in Python and its modularity makes the framework very flexible. The computationally demanding parts behind this interface are implemented in OpenCL, which enables fast calculations on modern graphics processing units. The combination of flexibility and speed opens new possibilities for studying novel imaging methods and systematic search of optimal combinations of measurement conditions and data processing parameters. This can help to increase the success rates and efficiency of valuable synchrotron beam time. To demonstrate the capabilities of the framework, various experiments have been simulated and compared with real data. To show the use case of measurement and data processing parameter optimization based on simulation, a virtual counterpart of a high-speed radiography experiment was created and the simulated data were used to select a suitable motion estimation algorithm; one of its parameters was optimized in order to achieve the best motion estimation accuracy when applied on the real data.syriswas also used to simulate tomographic data sets under various imaging conditions which impact the tomographic reconstruction accuracy, and it is shown how the accuracy may guide the selection of imaging conditions for particular use cases.

Hardening of Selective Laser Melted M2 Steel

2021 ◽  
Author(s):  
Mei Yang ◽  
Yishu Zhang ◽  
Haoxing You ◽  
Richard Smith ◽  
Richard D. Sisson
Keyword(s):  
Heat Treatment ◽  
High Speed ◽  
Cutting Tools ◽  
High Speed Steel ◽  
High Hardness ◽  
Steel Part ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Near Net Shape

Abstract Selective laser melting (SLM) is an additive manufacturing technique that can be used to make the near-net-shape metal parts. M2 is a high-speed steel widely used in cutting tools, which is due to its high hardness of this steel. Conventionally, the hardening heat treatment process, including quenching and tempering, is conducted to achieve the high hardness for M2 wrought parts. It was debated if the hardening is needed for additively manufactured M2 parts. In the present work, the M2 steel part is fabricated by SLM. It is found that the hardness of as-fabricated M2 SLM parts is much lower than the hardened M2 wrought parts. The characterization was conducted including X-ray diffraction (XRD), optical microscopy, Scanning Electron Microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) to investigate the microstructure evolution of as-fabricated, quenched, and tempered M2 SLM part. The M2 wrought part was heat-treated simultaneously with the SLM part for comparison. It was found the hardness of M2 SLM part after heat treatment is increased and comparable to the wrought part. Both quenched and tempered M2 SLM and wrought parts have the same microstructure, while the size of the carbides in the wrought part is larger than that in the SLM part.

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