A high-temperature environmental chamber for nuclear-resonant Bragg scattering studies

1998 ◽  
Vol 5 (3) ◽  
pp. 949-951
Author(s):  
J. Y. Zhao ◽  
X. W. Zhang ◽  
M. Ando
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
Room Temperature ◽  
Bragg Scattering ◽  
X Ray Diffraction ◽  
Environmental Chamber ◽  
X Ray ◽  
Compact Size ◽  
Scattering Study

A compact environmental chamber with a furnace operating in the range from room temperature to about 900 K has been built for a high-temperature nuclear-resonant Bragg scattering study. The compact size (75 mm diameter and 70 mm depth) allows an external magnetic field to be applied from outside permanent Nd–Fe–B alloy magnets; a magnetic field up to 1000 G has been obtained. The chamber can be mounted on a precise θ–2θ goniometer so that in situ observations of X-ray diffraction from a single crystal can be carried out. The temperature is measured by two thermocouples placed at the top and back of the sample and controlled by a PID controller. The temperature fluctuation of the chamber is less than ±1 K.

scholarly journals High-Temperature Tribological Performance of Hard Multilayer TiN-AlTiN/nACo-CrN/AlCrN-AlCrO-AlTiCrN Coating Deposited on WC-Co Substrate

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 909 ◽  
Author(s):  
Asad Alamgir ◽  
Maxim Yashin ◽  
Andrei Bogatov ◽  
Mart Viljus ◽  
Rainer Traksmaa ◽  
...  
Keyword(s):  
High Temperature ◽  
Room Temperature ◽  
Energy Dispersive Spectrometry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mechanical And Tribological Properties ◽  
Diamond Indenter ◽  
Scratch Tests ◽  
Ball On Disc

Mechanical and tribological properties of the hard-multilayer TiN-AlTiN/nACo-CrN/AlCrN-AlCrO-AlTiCrN coating deposited on WC-Co substrate were investigated. The sliding tests were carried out using ball-on-disc tribometer at room (25 °C) and high temperatures (600 and 800 °C) with Al2O3 balls as counterpart. Nano-scratch tests were performed at room temperature with a sphero-conical diamond indenter. The surface morphology and chemical composition were investigated with scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS) and in-situ high-temperature X-ray diffraction (HT-XRD). The phase transition from fcc-(Al,Cr)2O3 into α-(Al,Cr)2O3 was observed at about 800 °C. The results of the tribological tests depends on the temperature, the lowest apparent and real wear volumes were observed on the coating after the test at 800 °C along with the smallest coefficient of friction (COF). The plastic deformation of the coating was confirmed in sliding and nano-scratch tests. The nano-scratch tests revealed the dependence of COF value on the temperature of the sliding tests.

An In Situ High-Temperature X-Ray Diffraction Study of Phase Transformations in Maraging 300 Steel

2017 ◽  
Vol 371 ◽  
pp. 73-77 ◽  
Author(s):  
Adriano Gonçalves Reis ◽  
Danieli Aparecida Pereira Reis ◽  
Antônio Jorge Abdalla ◽  
Antônio Augusto Couto ◽  
Jorge Otubo
Keyword(s):  
High Temperature ◽  
Room Temperature ◽  
Volume Fraction ◽  
X Ray Diffraction ◽  
Austenite Transformation ◽  
X Ray ◽  
Xrd Diffraction ◽  
Temperature Solution ◽  
Diffraction Patterns

An in situ high-temperature X-ray diffraction (HTXRD) study in maraging 300 steel was carried out to study the martensite to austenite transformation and effect of time of exposure in the austenite reversion below austenite start temperature. Solution annealed materials were subjected to controlled heating-holding cycles. The first sample was heated at a rate of 10 oC/min from room temperature to 800 oC, showing that the microstructure is completely martensitic (α’110) until 600 oC. From 650 oC until 800 oC, the microstructure is gradually changing from martensitic to austenitic, showed by the increasing peaks of γ111 and reducing peaks of α’110. At 800 oC the microstructure is completely austenitic (γ111). Another sample was heated at 10 oC/min from room temperature to 600 oC and held for 4 hours. At 600 oC, at 0 h time of exposure, only a martensitic peak was observed. An austenite peak can be observed after some time of exposure at this temperature. The volume fraction of austenite increased with increasing time of exposure at 600 oC, reaching 50/50 volume fraction after 4 hours of exposure. XRD diffraction patterns for the same sample that was held for 4 hours at 600 oC and then cooled down in air to room temperature showed the same intensity of austenite and martensitic peaks found in situ at 600 oC for 4 hours (retained austenite), with the volume fraction of 50/50 of austenite and martensite phases. The HTXRD technique can be used to identify and quantify martensite to austenite transformation and austenite retention.

Phase relations in the Ba–Sr–Co–Fe–O system at 1273 K in air

2009 ◽  
Vol 42 (2) ◽  
pp. 153-160 ◽  
Author(s):  
Zhèn Yáng ◽  
Ashley S. Harvey ◽  
Anna Infortuna ◽  
Ludwig J. Gauckler
Keyword(s):  
High Temperature ◽  
Solid State ◽  
Solid State Reaction ◽  
Room Temperature ◽  
Solid State Reaction Method ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray

Selected compositions of the Ba–Sr–Co–Fe–O system were synthesized from powders by the solid-state reaction method. Samples were equilibrated at 1273 K for 36 000 s in air. The resulting powders were characterized by X-ray diffraction (XRD) at room temperature and by high-temperaturein situXRD. The phases present in the BaxSr1−xCoyFe1−yO3−δsystem are outlined for 1273 K in air. For most of the quaternary compositions, the cubic perovskite is formed, except for the compositions withx= 1 (excludingy= 0.4),y= 1 andx,y= 0.8, where the phases mainly show hexagonal distortions, andx, y= 0, for which a predominant cubic phase is mixed with other phases.

Development of the Compact Furnace for the In Situ Observation under Ultra-High Temperature by Synchrotron x-Ray Surface Diffraction

2016 ◽  
Vol 858 ◽  
pp. 505-508
Author(s):  
Masahiro Yoshida ◽  
Yasunori Kutsuma ◽  
Daichi Dohjima ◽  
Kenji Ohwada ◽  
Toshiya Inami ◽  
...  
Keyword(s):  
Crystal Growth ◽  
High Temperature ◽  
Room Temperature ◽  
Grazing Incidence ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Diffraction ◽  
Very High ◽  
Ultra High Temperature

We have established the grazing-incidence x-ray diffraction (GIXD) method under ultra- high temperature for in-situ crystal growth observation. For this purpose, we have developed the compact furnace which can be mounted on a goniometer used for the GIXD experiment. Using the custom-designed furnace, we have succeeded in controlling very high temperature around 1800°C. Subsequently, we have proved the performance of the furnace through the measurement of the tem- perature dependence of a-lattice constant of 4H-SiC in the range from room temperature to 1500 °C.

Mechanical Alloying Behavior in the Nb-Si, Ta-Si, and Nb-Ta-Si Systems

1988 ◽  
Vol 133 ◽  
Author(s):  
K. S. Kumar ◽  
S. K. Mannan
Keyword(s):  
High Temperature ◽  
Mechanical Alloying ◽  
Mechanical Milling ◽  
Room Temperature ◽  
Crystalline Compound ◽  
X Ray Diffraction ◽  
X Ray ◽  
Β Phase ◽  
Α Phase

ABSTRACTThe mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.

Photoluminescence Enhancement of CdS Nanocrystals Fabricated on Dithiocarbamate Functionalized PET Substrates

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.

In Situ Synchrotron X-Ray Diffraction Study of a Deformed Cu-Fe-P Alloy during Heating

2016 ◽  
Vol 850 ◽  
pp. 191-196 ◽  
Author(s):  
Wei Wang ◽  
Cun Lei Zou ◽  
Ren Geng Li ◽  
Wen Wen ◽  
Hui Jun Kang ◽  
...  
Keyword(s):  
Room Temperature ◽  
Lattice Distortion ◽  
Copper Matrix ◽  
Heating Process ◽  
Recrystallization Process ◽  
Full Width ◽  
X Ray Diffraction ◽  
Dramatic Decrease ◽  
X Ray

In situ synchrotron X-ray diffraction was used to study a deformed Cu-0.88 Fe-0.24 P alloy during heating process. The measurements were performed at room temperature and also at high temperatures up to 893 K in order to determine the recovery, ageing and recrystallization process. With the increase of temperature, the angles of copper matrix peaks moved left and the FWHM (full width at half maximum) decreased slightly. Fe3P precipitates were first detected at 533 K, reached the maximum at 673 K, and re-dissolved into matrix at 853 K. A dramatic decrease in FWHM was observed accompanied by the precipitation of Fe3P phases, indicating the reduction of lattice distortion of copper matrix.

Mechanically Driven Dissolution of Sn in Near-Equiatomic Bcc FeCo

2012 ◽  
Vol 194 ◽  
pp. 187-193 ◽  
Author(s):  
J.M. Loureiro ◽  
Benilde F.O. Costa ◽  
Gerard Le Caër ◽  
Bernard Malaman
Keyword(s):  
Magnetic Field ◽  
Solid Solutions ◽  
Room Temperature ◽  
Hyperfine Magnetic Field ◽  
Ternary Alloys ◽  
119Sn Mössbauer Spectroscopy ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Powder Mixtures ◽  
X Ray

Ternary alloys, (Fe50−x/2Co50−x/2)Snx(x ≤ 33 at.%), are prepared by mechanical alloying from powder mixtures of the three elements. As-milled alloys are studied by X-ray diffraction and 57Fe and 119Sn Mössbauer spectroscopy. The solubility of Sn in near-equiatomic bcc FeCo is increased from ~0.5 at. % at equilibrium to ~20 at.% in the used milling conditions. The average 119Sn hyperfine magnetic field at room temperature is larger, for any x, than the corresponding fields in mechanically alloyed Fe-Sn solid solutions.

scholarly journals Insertion of Phosphenium Ions into a Bicyclo[1.1.0]Tetraphosphabutane Iron Complex

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3920
Author(s):  
Martin Weber ◽  
Gábor Balázs ◽  
Alexander V. Virovets ◽  
Eugenia Peresypkina ◽  
Manfred Scheer
Keyword(s):  
Diffraction Analysis ◽  
Room Temperature ◽  
31P Nmr ◽  
Spectroscopic Studies ◽  
Iron Complex ◽  
The Novel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Phosphenium Ions

By reacting [{Cp‴Fe(CO)2}2(µ,η1:1-P4)] (1) with in situ generated phosphenium ions [Ph2P][A] ([A]− = [OTf]− = [O3SCF3]−, [PF6]−), a mixture of two main products of the composition [{Cp‴Fe(CO)2}2(µ,η1:1-P5(C6H5)2)][PF6] (2a and 3a) could be identified by extensive 31P NMR spectroscopic studies at 193 K. Compound 3a was also characterized by X-ray diffraction analysis, showing the rarely observed bicyclo[2.1.0]pentaphosphapentane unit. At room temperature, the novel compound [{Cp‴Fe}(µ,η4:1-P5Ph2){Cp‴(CO)2Fe}][PF6] (4) is formed by decarbonylation. Reacting 1 with in situ generated diphenyl arsenium ions gives short-lived intermediates at 193 K which disproportionate at room temperature into tetraphenyldiarsine and [{Cp‴Fe(CO)2}4(µ4,η1:1:1:1-P8)][OTf]2 (5) containing a tetracyclo[3.3.0.02,7.03,6]octaphosphaoctane ligand.

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