The Experts below are selected from a list of 216 Experts worldwide ranked by ideXlab platform
O. Isnard - One of the best experts on this subject based on the ideXlab platform.
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effect of hydrogen as Interstitial Element on the magnetic properties of some iron rich intermetallic compounds
Journal of Alloys and Compounds, 2011Co-Authors: O. IsnardAbstract:Some structural and magnetic properties of RFe11Ti and RFe11TiH compounds, both of which crystallize with the I4/mmm tetragonal ThMn12-type structure, are presented. The effect of hydrogen insertion on the ordering temperature and the iron sublattice contribution to the ordering of the RFe11Ti phase is investigated. Then the effects of hydrogen on the magnetic properties is discussed and compared to what has been reported for other series of iron rich intermetallic compounds such as R3Fe29−xMx, R2Fe17, RFe13−xMx and R2Fe14B, RFe2... It is shown that if similar effects including increase of the ordering temperature and of the saturation magnetization are observed for the R2Fe17, R(Fe,M)12, R3Fe29−xMx and R2Fe17 series, very different behaviour can also be observed for other series like RFe2 where hydrogen insertion can be detrimental to the magnetic properties.
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Ce Valence State Probed by XAFS Study in Ce2Fe17-xGaxMyCompounds (M = Light Interstitial Element)
Le Journal de Physique IV, 1997Co-Authors: O. Isnard, S. Miraglia, P. Wolfers, G. Krill, D. FruchartAbstract:In the Ce2Fel7 alloy, cerium is known to be in an intermediate valence state. The sensitivity of cerium electronic state to its environment has been probed by XAFS experiment on the XAS3 station of the DCI Synchrotron radiation facility at LURE. We have studied the influence of Interstitial Element insertion on one hand and/or iron substitution by Ga on the other hand on the Ce L3 absorption edge. The results of XAFS are discussed in the light of neutron diffraction experiments that yield the Interstitial Element location and the substitution scheme in the local environment. This study shows that the large macroscopic magnetic change induces a significant evolution of the Ce L3 absorption edge. A partial relocalization of the 4f states is observed
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ce valence state probed by xafs study in ce2fe17 xgaxmy compounds m light Interstitial Element
Journal De Physique Iv, 1997Co-Authors: O. Isnard, S. Miraglia, P. Wolfers, G. Krill, D. FruchartAbstract:In the Ce 2 Fe 17 alloy, cerium is known to be in an intermediate valence state. The sensitivity of cerium electronic state to its environment has been probed by XAFS experiment on the XAS3 station of the DCI Synchrotron radiation facility at LURE. We have studied the influence of Interstitial Element insertion on one hand and/or iron substitution by Ga on the other hand on the Ce L 3 absorption edge. The results of XAFS are discussed in the light of neutron diffraction experiments that yield the Interstitial Element location and the subsitution scheme in the local environment. this study shows that the large macroscopic magnetic change induces a significant evolution of the Ce L3 absorption edge. A partial relocalization of the 4f states is observed.
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Ce Valence State Probed by XAFS Study in Ce2Fe17-xGaxMy Compounds (M = Light Interstitial Element)
Journal De Physique Iv, 1997Co-Authors: O. Isnard, S. Miraglia, P. Wolfers, G. Krill, D. FruchartAbstract:In the Ce 2 Fe 17 alloy, cerium is known to be in an intermediate valence state. The sensitivity of cerium electronic state to its environment has been probed by XAFS experiment on the XAS3 station of the DCI Synchrotron radiation facility at LURE. We have studied the influence of Interstitial Element insertion on one hand and/or iron substitution by Ga on the other hand on the Ce L 3 absorption edge. The results of XAFS are discussed in the light of neutron diffraction experiments that yield the Interstitial Element location and the subsitution scheme in the local environment. this study shows that the large macroscopic magnetic change induces a significant evolution of the Ce L3 absorption edge. A partial relocalization of the 4f states is observed.
I S Tereshina - One of the best experts on this subject based on the ideXlab platform.
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magnetic phase transitions in intermetallic Interstitial Element h or n systems fundamentals and potentialities
Journal of Magnetism and Magnetic Materials, 2006Co-Authors: I S TereshinaAbstract:Abstract Fundamentals of magnetic anisotropy and spin-reorientation phase transitions in the R–Fe intermetallic compounds are discussed. The modification and arising the spin reorientation transitions (SRT) caused by the presence of hydrogen and nitrogen atoms in Interstitial positions are reviewed for the RFe 11 Ti and the R 2 Fe 17 (R=Y, Sm, Gd, Tb, Dy, Ho, Er and Lu) compounds. It was shown the possibility to control magnetic properties of the compounds via the insertion of Interstitial atoms. This is of great importance to develop new magnetic materials with given properties.
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Magnetic phase transitions in intermetallic–Interstitial Element (H or N) systems: Fundamentals and potentialities
Journal of Magnetism and Magnetic Materials, 2006Co-Authors: I S TereshinaAbstract:Abstract Fundamentals of magnetic anisotropy and spin-reorientation phase transitions in the R–Fe intermetallic compounds are discussed. The modification and arising the spin reorientation transitions (SRT) caused by the presence of hydrogen and nitrogen atoms in Interstitial positions are reviewed for the RFe 11 Ti and the R 2 Fe 17 (R=Y, Sm, Gd, Tb, Dy, Ho, Er and Lu) compounds. It was shown the possibility to control magnetic properties of the compounds via the insertion of Interstitial atoms. This is of great importance to develop new magnetic materials with given properties.
D. Fruchart - One of the best experts on this subject based on the ideXlab platform.
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Ce Valence State Probed by XAFS Study in Ce2Fe17-xGaxMyCompounds (M = Light Interstitial Element)
Le Journal de Physique IV, 1997Co-Authors: O. Isnard, S. Miraglia, P. Wolfers, G. Krill, D. FruchartAbstract:In the Ce2Fel7 alloy, cerium is known to be in an intermediate valence state. The sensitivity of cerium electronic state to its environment has been probed by XAFS experiment on the XAS3 station of the DCI Synchrotron radiation facility at LURE. We have studied the influence of Interstitial Element insertion on one hand and/or iron substitution by Ga on the other hand on the Ce L3 absorption edge. The results of XAFS are discussed in the light of neutron diffraction experiments that yield the Interstitial Element location and the substitution scheme in the local environment. This study shows that the large macroscopic magnetic change induces a significant evolution of the Ce L3 absorption edge. A partial relocalization of the 4f states is observed
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ce valence state probed by xafs study in ce2fe17 xgaxmy compounds m light Interstitial Element
Journal De Physique Iv, 1997Co-Authors: O. Isnard, S. Miraglia, P. Wolfers, G. Krill, D. FruchartAbstract:In the Ce 2 Fe 17 alloy, cerium is known to be in an intermediate valence state. The sensitivity of cerium electronic state to its environment has been probed by XAFS experiment on the XAS3 station of the DCI Synchrotron radiation facility at LURE. We have studied the influence of Interstitial Element insertion on one hand and/or iron substitution by Ga on the other hand on the Ce L 3 absorption edge. The results of XAFS are discussed in the light of neutron diffraction experiments that yield the Interstitial Element location and the subsitution scheme in the local environment. this study shows that the large macroscopic magnetic change induces a significant evolution of the Ce L3 absorption edge. A partial relocalization of the 4f states is observed.
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Ce Valence State Probed by XAFS Study in Ce2Fe17-xGaxMy Compounds (M = Light Interstitial Element)
Journal De Physique Iv, 1997Co-Authors: O. Isnard, S. Miraglia, P. Wolfers, G. Krill, D. FruchartAbstract:In the Ce 2 Fe 17 alloy, cerium is known to be in an intermediate valence state. The sensitivity of cerium electronic state to its environment has been probed by XAFS experiment on the XAS3 station of the DCI Synchrotron radiation facility at LURE. We have studied the influence of Interstitial Element insertion on one hand and/or iron substitution by Ga on the other hand on the Ce L 3 absorption edge. The results of XAFS are discussed in the light of neutron diffraction experiments that yield the Interstitial Element location and the subsitution scheme in the local environment. this study shows that the large macroscopic magnetic change induces a significant evolution of the Ce L3 absorption edge. A partial relocalization of the 4f states is observed.
Carlos Roberto Grandini - One of the best experts on this subject based on the ideXlab platform.
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Effect of Some Heat Treatments on Anelastic Properties of Ti-15Zr-xMo Alloys
Materials Science Forum, 2020Co-Authors: Diego Rafael Nespeque Correa, M.l. Lourenço, Pedro Akira Bazaglia Kuroda, Marília Afonso Rabelo Buzalaf, Carlos Roberto GrandiniAbstract:Ti and Ti-based alloys have favorable properties for biomedical applications, such as high specific strength, low Young’s modulus, excellent corrosion and wear resistance, and good biocompatibility. The addition of alloying Elements and heat treatments can result in a good combination of properties. Mo and Zr are β-stabilizer Elements that decrease the Young’s modulus and increase the mechanical strength and corrosion resistance. Oxygen is an Interstitial Element that can improve mechanical strength and prevent ω phase formation. In this study, we analyzed the influence of substitutional and Interstitial Elements, and some heat treatments in the crystalline structure, microstructure and selected mechanical properties (Vickers microhardness, Young’s modulus and internal friction) of Ti-15Zr-xMo (5, 10, 15 and 20 wt%) alloys. The alloys exhibited dependence on the alloying Elements and heat treatments, which resulted in different structural and microstructural changes. The mechanical properties were dependent on phase transformations induced by the compositions and heat treatments.
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Adjustment of the microstructure and selected mechanical properties of biomedical Ti-15Zr-Mo alloys through oxygen doping
Journal of Alloys and Compounds, 2019Co-Authors: D. R. N. Correa, Pedro Akira Bazaglia Kuroda, M.l. Lourenço, Marília Afonso Rabelo Buzalaf, Carlos Roberto GrandiniAbstract:Abstract This study investigated the effect of oxygen doping on the crystalline structure, microstructure, and selected mechanical properties (Vickers microhardness, Young's modulus and internal friction) of Ti-15Zr-xMo (x = 5, 7.5, 10, 15 and 20 wt%) alloys for use as biomaterials. The monitoring of oxygen pressure along with the doping treatment indicated that the Interstitial Element was successfully absorbed into the samples. Results showed that oxygen content slightly altered the α”/β phase proportion and β phase crystalline parameter without abruptly changing their microstructure. Moreover, the selected mechanical properties suffered variations in a non-linear manner. Oxygen content was found to be suitable to produce small variations in the microstructure and in the selected properties of biomedical Ti alloys, keeping the main composition unchanged.
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Stress induced ordering due Interstitials in Nb–4.7 at.%Ta
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2005Co-Authors: L. H. De Almeida, Carlos Roberto Grandini, Jpb Machado, D. RodriguesAbstract:Abstract The presence of Interstitial Elements in metals cause strong changes in their physical, chemical or mechanical properties. These Interstitial impurities interact with the metallic matrix atoms by a relaxation process known as stress induced ordering. Relaxation processes give rise to a peak in the internal friction spectrum, known as Snoek effect. The presence of substitutional solutes has a strong influence on Snoek effect, particularly if the substitutional solute Element is the one, which interacts with the Interstitial Element. Anelastic spectroscopy measurements provide information of the behavior of these impurities in the metallic matrix. In this paper, polycrystalline samples of Nb–4.7 at.%Ta alloy have been analyzed in the as-received condition. Measurements of anelastic spectroscopy were carried out using an inverted torsion pendulum, operating with frequency of 2.0–30.0 Hz and in a temperature range between 300 and 700 K. It was observed the presence of a relaxation structure that have been attributed to stress induced ordering due to Interstitial atoms around atoms of the metallic matrix. The relaxation structure have been decomposed in its constituent peaks, what it allowed to identify the following relaxation processes: Ta–O, Nb–O and Nb–N.
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Activation Energy Measurement of Oxygen Ordering in a Nb-Ti Alloy by Anelastic Relaxation
Materials Research-ibero-american Journal of Materials, 2002Co-Authors: Terlize Cristina Niemeyer, Juliana Maria De Albuquerque Gimenez, Luciano Henrique De Almeida, Carlos Roberto Grandini, Odila FlorêncioAbstract:Metals with bcc structure are able to dissolve large amounts of Interstitial Element atoms in the form of oxygen. These atoms diffuse through the lattice by jumping into octahedral sites with equivalent symmetry, causing strong alterations in the anelastic behavior. This paper reports on a study of Snoek relaxation in Nb-Ti alloys with oxygen in solid solution, based on internal friction as a function of temperature. The internal friction measurements were taken in a torsion pendulum operating at temperatures in the range of 350 to 650 K, with frequencies varying from 6 to 36 Hz. The results show relaxation spectra in which thermally activated relaxation peaks produced by the stress-induced ordering of oxygen atoms around niobium atoms of the metallic matrix were identified.
M T Vieira - One of the best experts on this subject based on the ideXlab platform.
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Influence of Ti addition on the properties of W–Ti–C/N sputtered films
Surface & Coatings Technology, 2003Co-Authors: Albano Cavaleiro, Bruno Trindade, M T VieiraAbstract:Thin films of W–Ti–CyN were deposited by d.c. reactive magnetron sputtering from W–Ti targets with 0, 10, 20 and 30 wt.%Ti. The influence of titanium and Interstitial Element (carbon and nitrogen) contents on the structure, hardness and adhesion of the coatings was evaluated by X-ray diffraction analysis, ultramicroindentation and scratch-testing, respectively. The results show different compositional dependencies of the structure and grain size of the films. Hardness was related with the structure of the films, including lattice distortion and grain size. The higher hardness values (f50 GPa) were obtained for W–Ti–N films with 40–45 at.%N deposited from the W–20 wt.%Ti target in a reactive N atmosphere. However, these films present relatively 2 low adhesion to the substrates with critical loads of 30 N. The best compromise between hardness and adhesion was reached for W–Ti–N films with low nitrogen and titanium contents. 2003 Elsevier Science B.V. All rights reserved.
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the influence of the Interstitial Element on tribological behaviour of tungsten coatings
Surface & Coatings Technology, 1998Co-Authors: J M Castanho, M T VieiraAbstract:Abstract It is well known that one way to increase the mechanical strength of a metal is by the incorporation of Interstitial Elements. Previous work on sputtered tungsten doped with small quantities of nitrogen showed that the hardness of these coatings increased with the incorporation of an Interstitial Element. The main purpose of this work is to understand the effect of the Interstitial Elements (carbon and nitrogen) in the tungsten matrix, on the wear properties of sputtered coatings. Coatings of W, W(N) and W(C) were deposited by DC reactive sputtering. The tribological behaviour was evaluated in pin-on-disk and scratch-tests. The tribological behaviour was correlated with morphology, structure and chemical composition.
