Study of 3-D stress development in parent and twin pairs of a hexagonal close-packed polycrystal: Part I – in-situ three-dimensional synchrotron X-ray diffraction measurement

We have developed magnetically oriented microcrystal array (MOMA) technique that enables single crystal X-ray diffraction analyses from microcrystalline powder. In this method, microcrystals suspended in a UV-curable monomer matrix are there-dimensionally aligned by special rotating magnetic field, followed by consolidation of the matrix by photopolymerization. From thus achieved MOMAs, we have been succeeded in crystal structure analysis for some substances [1, 2]. Though MOMA method is an effective technique, it has some problems as follows: in a MOMA, the alignment is deteriorated during the consolidation process. In addition, the sample microcrystals cannot be recovered from a MOMA. To overcome these problems, we performed an in-situ X-ray diffraction measurement using a three-dimensional magnetically oriented microcrystal suspension (3D MOMS) of L-alanine. An experimental setting of the in-situ X-ray measurement of MOMS is schematically shown in the figure. L-alanine microcrystal suspension was poured into a glass capillary and placed on the rotating unit equipped with a pair of neodymium magnets. Rotating X-ray chopper with 10°-slits was placed between the collimator and the suspension. By using this chopper, it was possible to expose the X-ray only when the rotating MOMS makes a specific direction with respect to the impinging X-ray. This has the same effect as the omega oscillation in conventional single crystal measurement. A total of 22 XRD images of 10° increments from 0° to 220° were obtained. The data set was processed by using conventional software to obtain three-dimensional molecular structure of L-alanine. The structure is in good agreement with that reported for the single crystal. R1 and wR2 were 6.53 and 17.4 %, respectively. RMSD value between the determined molecular structure and the reported one was 0.0045 Å. From this result, we conclude that this method can be effective and practical to be used widely for crystal structure analyses.

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X-Ray Diffraction of Magnetically Oriented Microcrystals of Protein

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314096508 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C349-C349

Author(s):

Shu Tsukui ◽

Fumiko Kimura ◽

Kimihiko Mizutani ◽

Bunzo Mikami ◽

Tsunehisa Kimura

Keyword(s):

Single Crystal ◽

Three Dimensional ◽

Water Soluble ◽

Dimensional Structure ◽

Diffraction Measurement ◽

X Ray Diffraction ◽

Consolidation Process ◽

X Ray ◽

Three Dimensional Structure

Elucidation of the three-dimensional structure of biomolecules is of great importance because the three-dimensional structure is closely related to biological functions. X-ray single-crystal analysis is powerful method to analyze the structure, but it is sometimes difficult to grow a crystal sufficiently large for conventional or even synchrotron single-crystal X-ray measurement. We recently reported on a magnetically oriented microcrystal array (MOMA) [1] that is a composite in which microcrystals are aligned three-dimensionally in polymer matrix. Microcrystals are suspended in an ultraviolet-curable monomer and rotated non-uniformly in a static magnetic field to achieve three dimensional crystal alignment. Then, the monomer is photopolymerized to maintain the achieved alignment. We have successfully demonstrated that X-ray single crystal structure determinations through MOMA are possible for low molecular weight compounds [2] as well as protein. [3] However, the method with MOMA has two drawbacks: (i) the sample microcrystals cannot be recovered from a MOMA, which is especially serious problem in case of proteins, and (ii) the alignment is deteriorated during the consolidation process, causing low resolution. In this study, we attempt to solve these problems. First, we use a water-soluble sol as microcrystalline media and consolidate the alignment by gelation, which makes the recovery of microcrystals possible. Second, a magnetically oriented microcrystal suspension (MOMS) is used for in-situ X-ray diffraction measurement, which makes the sample recovery possible and enhances the resolution. We use lysozyme as a model protein for both cases. The in-situ method with in-house X-ray diffractometer gave diffraction spots about 3.0 Å resolutions. We plan to perform the same experiment at SPring-8.

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Formation and annihilation of stressed deformation twins in magnesium

Communications Materials ◽

10.1038/s43246-020-00105-y ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Karim Louca ◽

Hamidreza Abdolvand ◽

Charles Mareau ◽

Marta Majkut ◽

Jonathan Wright

Keyword(s):

Mechanical Response ◽

Axial Stress ◽

Three Dimensional ◽

Service Performance ◽

Polycrystalline Materials ◽

X Ray Diffraction ◽

Sign Reversal ◽

X Ray ◽

Hexagonal Close Packed

AbstractThe mechanical response of polycrystalline materials to an externally applied load and their in-service performance depend on the local load partitioning among the constituent crystals. In hexagonal close-packed polycrystals such load partitioning is significantly affected by deformation twinning. Here we report in-situ compression-tension experiments conducted on magnesium specimens to measure the evolution of grain resolved tensorial stresses and formation and annihilation of twins. More than 13000 grains and 1300 twin-parent pairs are studied individually using three-dimensional synchrotron X-ray diffraction. It is shown that at the early stages of plasticity, the axial stress in twins is higher than that of parents, yet twins relax with further loading. While a sign reversal is observed for the resolved shear stress (RSS) acting on the twin habit plane in the parent, the sign of RSS within the majority of twins stays unchanged until twin annihilation during the load reversal. The variations of measured average stresses across parents and twins are also investigated.

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Photoluminescence Enhancement of CdS Nanocrystals Fabricated on Dithiocarbamate Functionalized PET Substrates

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1511 ◽

2012 ◽

Vol 512-515 ◽

pp. 1511-1515

Author(s):

Chun Lin Zhao ◽

Li Xing ◽

Xiao Hong Liang ◽

Jun Hui Xiang ◽

Fu Shi Zhang ◽

...

Keyword(s):

Room Temperature ◽

Hexagonal Structure ◽

Diffraction Measurement ◽

X Ray Diffraction ◽

Visible Absorption ◽

X Ray ◽

Cds Nanocrystals ◽

Morphological Studies ◽

Transmission Electron

Cadmium sulfide (CdS) nanocrystals (NCs) were self-assembled and in-situ immobilized on the dithiocarbamate (DTCs)-functionalized polyethylene glycol terephthalate (PET) substrates between the organic (carbon disulfide diffused in n-hexane) –aqueous (ethylenediamine and Cd2+ dissolved in water) interface at room temperature. Powder X-ray diffraction measurement revealed the hexagonal structure of CdS nanocrystals. Morphological studies performed by scanning electron microscopy (SEM) and high-resolution transmission electron microscope (HRTEM) showed the island-like structure of CdS nanocrystals on PET substrates, as well as energy-dispersive X-ray spectroscopy (EDS) confirmed the stoichiometries of CdS nanocrystals. The optical properties of DTCs modified CdS nanocrystals were thoroughly investigated by ultraviolet-visible absorption spectroscopy (UV-vis) and fluorescence spectroscopy. The as-prepared DTCs present intrinsic hydrophobicity and strong affinity for CdS nanocrystals.

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In-Situ X-ray Diffraction Measurement for Pure Niobium Metal in High Temperature Hydrogen Atmosphere

Journal of the Japan Institute of Metals and Materials ◽

10.2320/jinstmet.70.467 ◽

2006 ◽

Vol 70 (6) ◽

pp. 467-472 ◽

Cited By ~ 2

Author(s):

Tomonori Nambu ◽

Nobue Shimizu ◽

Hisakazu Ezaki ◽

Hiroshi Yukawa ◽

Masahiko Morinaga ◽

...

Keyword(s):

High Temperature ◽

Hydrogen Atmosphere ◽

Diffraction Measurement ◽

X Ray Diffraction ◽

X Ray ◽

Pure Niobium

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In Situ Coherent X-ray Diffraction during Three-Point Bending of a Au Nanowire: Visualization and Quantification

Quantum Beam Science ◽

10.3390/qubs2040024 ◽

2018 ◽

Vol 2 (4) ◽

pp. 24 ◽

Cited By ~ 4

Author(s):

Anton Davydok ◽

Thomas Cornelius ◽

Zhe Ren ◽

Cedric Leclere ◽

Gilbert Chahine ◽

...

Keyword(s):

Three Dimensional ◽

Reciprocal Space ◽

X Ray Diffraction ◽

Complex Deformation ◽

X Ray ◽

Three Point Bending ◽

Atomic Force ◽

Au Nanowire ◽

Before And After

The three-point bending behavior of a single Au nanowire deformed by an atomic force microscope was monitored by coherent X-ray diffraction using a sub-micrometer sized hard X-ray beam. Three-dimensional reciprocal-space maps were recorded before and after deformation by standard rocking curves and were measured by scanning the energy of the incident X-ray beam during deformation at different loading stages. The mechanical behavior of the nanowire was visualized in reciprocal space and a complex deformation mechanism is described. In addition to the expected bending of the nanowire, torsion was detected. Bending and torsion angles were quantified from the high-resolution diffraction data.

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Three dimensional V2O5/NaV6O15 hierarchical heterostructures: Controlled synthesis and synergistic effect investigated by in situ X-ray diffraction

Nano Energy ◽

10.1016/j.nanoen.2016.06.057 ◽

2016 ◽

Vol 27 ◽

pp. 147-156 ◽

Cited By ~ 38

Author(s):

Chaojiang Niu ◽

Xiong Liu ◽

Jiashen Meng ◽

Lin Xu ◽

Mengyu Yan ◽

...

Keyword(s):

Synergistic Effect ◽

Three Dimensional ◽

Controlled Synthesis ◽

X Ray Diffraction ◽

X Ray

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Crystal plasticity in shock-compressed hcp-iron

10.5194/egusphere-egu21-13568 ◽

2021 ◽

Author(s):

Sébastien Merkel ◽

Sovanndara Hok ◽

Cynthia Bolme ◽

Wendy Mao ◽

Arianna Gleason

Keyword(s):

Free Electron ◽

Deformation Mechanisms ◽

Free Electron Lasers ◽

X Ray Diffraction ◽

X Ray ◽

Hexagonal Close Packed ◽

Planetary Cores ◽

Materials Behavior ◽

Optical Laser

<p>Iron is a key constituent of planetary core and an important technological material. Here, we combine <em>in situ</em> ultrafast X-ray diffraction at free electron lasers with optical-laser-induced shock compression experiments on polycrystalline Fe to study the plasticity of hexagonal close-packed (hcp)-Fe under extreme loading states. We identifiy the deformation mechanisms that controls the Fe microstructures and&#160; observe a significant time-evolution of stress over the few nanoseconds of the experiments. These observations illustrate how ultrafast plasticity studies can reveal distinctive materials behavior under extreme loading states and will help constraining the pressure, temperature, and strain rate dependence of materials behavior in planetary cores.</p>

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