The Experts below are selected from a list of 2631 Experts worldwide ranked by ideXlab platform
P. Vajda - One of the best experts on this subject based on the ideXlab platform.
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On the K State Effect in Interstitial Alloys:. Anomalous Resistivity Behavior in Damaged β-PdH(D) 0.63
Modern Physics Letters B, 1994Co-Authors: P. VajdaAbstract:After a brief description of the K state phenomenon in short-range-ordered substitutional Alloys, it is shown that this effect also exists in an Interstitial Alloy β-PdH(D)0.63, whose low-temperature resistivity decreases after a quench across the order-disorder transition region around 50 K and/or after electron irradiation.
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Order-disorder transition in the system CeH2+x
Journal of Physics and Chemistry of Solids, 1993Co-Authors: I.g. Ratishvili, P. Vajda, A. BoukraaAbstract:Abstract The ordering mechanism in the excess-hydrogen system of the Interstitial Alloy CeH2 + x is described based on the mean-field approximation of the static-concentration-waves theory and using the results of neutron-diffraction experiments. The computed order-disorder transition temperatures (normalized at c = 0.25) agree with the various available experimental data quite satisfactorily, in the concentration range 0.13 ≲ c ≲ 0.5, but seem to be overestimated for c > 0.5, probably due to the increasing role of the lattice contraction with increasing c. The character of the transition changes progressively from first to second order above a critical concentration co ~ 0.3.
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Ordering in the system β-TbD2+x
Physical Review B, 1993Co-Authors: P. VajdaAbstract:The ordering process in the hydrogen subsystem of the Interstitial Alloy TbD 2+x is described with the mean-field approximation to static-concentration wave theory and with the results of neutron-diffraction experiments. It is shown that the measured temperature dependence of the intensity for the superstructure reflections in the Alloy with composition TbD 2.18 is well represented by the calculated temperature dependence of the square of the order parameter. Furthermore, the computed transition temperatures for Alloys with different concentrations x in the range 0≤x≤0.25 are close to those determined from resistivity and neutron-scattering experiments
C Tran Dinh - One of the best experts on this subject based on the ideXlab platform.
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Thermodynamic properties of BCC Interstitial Alloy FeH under pressure
IOP Conference Series: Materials Science and Engineering, 2019Co-Authors: T H Nguyen, Q H Nguyen, G Coman, V Dinh Quang, C Tran DinhAbstract:The analytic expressions of the mean nearest neighbor distance, the free energy and the thermodynamic quantities for Interstitial Alloy AB with body-centered cubic (BCC) structure under pressure are derived by the statistical moment method. The theoretical results are applied to Interstitial Alloy FeH. Our calculated results for Fe as main metal are in good agreement with experiments.
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Thermodynamic properties of FCC Interstitial Alloy AuSi with defects
IOP Conference Series: Materials Science and Engineering, 2019Co-Authors: T H Nguyen, Q H Nguyen, G Coman, C Tran Dinh, V Le HongAbstract:The analytic expressions for free energy, concentration of the equilibrium vacancies and thermodynamic quantities such as the isothermal compressibility, thermal expansion coefficient and heat capacities at constant volume and at constant pressure of FCC Interstitial Alloy AB with defects under pressure are derived by the statistical moment method. The theoretical results are applied to AuSi Interstitial Alloy. Our calculated results for main metal Au are compared with the experimental data.
D Lopez - One of the best experts on this subject based on the ideXlab platform.
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effect of the cooling rate in the corrosion behavior of a hot worked ti 6al 4v extra low Interstitial Alloy
Materials & Design, 2014Co-Authors: S Mayajohnson, D LopezAbstract:Abstract This work discusses the effect of the cooling rate during a forging process on the microstructure and corrosion behavior of a Ti–6Al–4V extra-low Interstitial (ELI) Alloy, which is commonly used as biomaterial. The samples were hot forged at two different temperatures, both of them within the dual phase field (α + β) and a constant strain rate of 4 × 10−3 s−1 was employed during the tests. The samples were cooled in three different cooling media (water, air and clay) and the microstructure was analyzed using scanning electron microscopy (SEM). The corrosion resistance was determined by cyclic polarization tests in Ringer’s solution at 37 °C. Comparison between the results obtained for forged and commercial samples allowed to establish some correlations between cooling rate, microstructure and corrosion resistance. It was found that the clay as a cooling medium is a good candidate to obtain a proper microstructure and properties for biomedical applications, eliminating the requirement of subsequent heat treatment and reducing costs.
Tran Dinh Cuong - One of the best experts on this subject based on the ideXlab platform.
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Study on the melting of Interstitial Alloys FeH and FeC with BCC structure under pressure
Chinese Journal of Physics, 2019Co-Authors: Le Thi Cam Tuyen, Bui Duc Tinh, Dinh Quang Vinh, Nguyen Quang Học, Tran Dinh CuongAbstract:Abstract From the model of Interstitial Alloy AB with BCC structure and the condition of absolute stability for crystalline state we derive analytic expression for the temperature of absolute stability for crystalline state, the melting temperature and the equation of melting curve of this Alloy by the way of applying the statistical moment method. The obtained results allow us to determine the melting temperature of Alloy AB at zero pressure and under pressure. In limit cases, we obtain the melting theory of A main metal with BCC structure. The theoretical results are numerically applied for Alloys FeH and FeC with using different potentials.
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Thermodynamic and Elastic Properties of Interstitial Alloy FeC with BCC Structure at Zero Pressure
Advances in Materials Science and Engineering, 2018Co-Authors: Bui Duc Tinh, Nguyen Quang Hoc, Dinh Quang Vinh, Tran Dinh Cuong, Nguyen Duc HienAbstract:The analytic expressions for the thermodynamic and elastic quantities such as the mean nearest neighbor distance, the free energy, the isothermal compressibility, the thermal expansion coefficient, the heat capacities at constant volume and at constant pressure, the Young modulus, the bulk modulus, the rigidity modulus, and the elastic constants of binary Interstitial Alloy with body-centered cubic (BCC) structure, and the small concentration of Interstitial atoms (below 5%) are derived by the statistical moment method. The theoretical results are applied to Interstitial Alloy FeC in the interval of temperature from 100 to 1000 K and in the interval of Interstitial atom concentration from 0 to 5%. In special cases, we obtain the thermodynamic quantities of main metal Fe with BCC structure. Our calculated results for some thermodynamic and elastic quantities of main metal Fe and Alloy FeC are compared with experiments.
Keisuke Ishikawa - One of the best experts on this subject based on the ideXlab platform.
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Transmission electron microscopy study of high cycle fatigue deformation in Ti5Al2.5Sn extra-low Interstitial Alloy at cryogenic temperatures
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 1990Co-Authors: Osamu Umezawa, Kotobu Nagai, Keisuke IshikawaAbstract:Abstract The dislocation structure developed in an α-type Ti5Al2.5Sn extra-low Interstitial Alloy under various cyclic stresses at cryogenic temperatures was investigated by transmission electron microscopy. When the maximum stress was above the yield strength, coplanar dislocation arrays were distributed over α grains. Prism slip occurred predominantly and a pyramidal slip system was also activated. As the maximum stress was decreased, dislocation pile-ups became less homogeneously distributed. The dislocation arrays on the prism plane passed through grain boundaries. When the maximum stress was below about 75% of the yield strength, where the present Alloy showed subsurface fatigue crack initiation, dislocations were piled up and blocked at grain boundaries in the small α grain region. Slip occurred predominantly along prism planes and the Burgers vector of the dislocation was .
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Subsurface crack initiation in high cycle fatigue of Ti5Al2.5Sn extra-low Interstitial Alloy at liquid helium temperature
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 1990Co-Authors: Osamu Umezawa, Kotobu Nagai, Keisuke IshikawaAbstract:Abstract Subsurface fatigue crack initiation in a Ti5Al2.5Sn extra-low Interstitial Alloy at liquid helium temperature was characterized. The subsurface crack initiation occurred at low stress level and neither defects nor foreign material were detected at the subsurface initiation site. The subsurface crack initiation site was composed of “small grains” of diameter about 5–10 μm. The concentration of aluminium at the initiation site was much lower than in the bulk. From the viewpoint of the microstructure this Alloy had partly a two-phase region (small α grain region). It was composed of small α grains with low aluminium content and an iron-enriched β phase at their grain boundaries. The size, morphology and composition of the subsurface crack initiation site fitted those of the small α grain region. Hence it is concluded that the subsurface crack was initiated in the small α grain region.
