X‐ray observation of compositional modulation caused by phase decomposition in GaInP ternary alloys

1990 ◽  
Vol 56 (4) ◽  
pp. 337-339 ◽  
Author(s):  
Hiroshi Okuda ◽  
Makoto Kondo ◽  
Kiyoko Kato ◽  
Kazuo Nakajima
Keyword(s):  
Ternary Alloys ◽  
Phase Decomposition ◽  
X Ray ◽  
Compositional Modulation

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 Influence of the Al content on the phase transformations in Cu-Al-Ag alloys

2003 ◽  
Vol 28 (1) ◽  
pp. 33-38 ◽  
Author(s):  
A. T. Adorno ◽  
A. V. Benedetti ◽  
R. A. G. da Silva ◽  
M. Blanco
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Transition Temperature ◽  
Phase Transformations ◽  
Decomposition Reaction ◽  
Phase Decomposition ◽  
Stability Range ◽  
X Ray ◽  
Al Content ◽  
The Stability

The influence of the Al content on the phase transformations in Cu-Al-Ag alloys was studied by classical differential thermal analysis (DTA), optical microscopy (OM) and X-ray diffractometry (XRD). The results indicated that the increase in the Al content and the presence of Ag decrease the rate of the <FONT FACE=Symbol>b</font>1 phase decomposition reaction and contribute for the raise of this transition temperature, thus decreasing the stability range of the perlitic phase resulted from the b1 decomposition reaction.

Compositional Modulation and its Optoelectric Properties of Zn(S,Se,Te) Crystals Grown by Hydrogen Radical-Enhanced CVD

1995 ◽  
Vol 417 ◽  
Author(s):  
Hiroyuki Fujiwara ◽  
Toshihiro Ii ◽  
Isamu Shimizu
Keyword(s):  
Deep Level ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Small Shift ◽  
X Ray ◽  
Compositional Modulation ◽  
Peak Energy ◽  
Large Lattice ◽  
The Difference ◽  
Hydrogen Radical

AbstractHigh-quality (ZnS)n(ZnSe)12n and (ZnSe)n(ZnTe)11n (n=1∼4) crystals were grown at a low temperature of 200°C by hydrogen radical-enhanced chemical vapor deposition. From satellite peaks in x-ray diffraction spectra, these periodic structure crystals were confirmed to be grown coherently on substrates, in spite of large lattice mismatches between the grown layers and the substrates (͛=4∼7%). In photoluminescence (PL) spectra of these films, strong band-edge emissions were predominantly observed, resulting from a suppression of deep-level emissions. We found that the PL peak energy of (ZnSe)n(ZnTe)11n shifts systematically to lower energy by 200 meV with changes in the number of ZnSe layers (n), while relatively small shift of 13 meV was observed in (ZnS)n(ZnSe)12n. These discrepancy can be attributed to the difference of band-lineups or chemical natures of constituent atoms in these crystals.

scholarly journals Mn-Induced Thermal Stability of L10 Phase in Fept Magnetic Nanoscale Ribbons

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1278
Author(s):  
Alina Daniela Crisan ◽  
Aurel Leca ◽  
Dan Pantelica ◽  
Ioan Dan ◽  
Ovidiu Crisan
Keyword(s):  
Rare Earth ◽  
Single Phase ◽  
Permanent Magnets ◽  
Magnetic Hysteresis ◽  
Ternary Alloys ◽  
Large Temperature ◽  
Nominal Composition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Operation Conditions

Magnetic nanoscale materials exhibiting the L10 tetragonal phase such as FePt or ternary alloys derived from FePt show most promising magnetic properties as a novel class of rare earth free permanent magnets with high operating temperature. A granular alloy derived from binary FePt with low Pt content and the addition of Mn with the nominal composition Fe57Mn8Pt35 has been synthesized in the shape of melt-spun ribbons and subsequently annealed at 600 °C and 700 °C for promoting the formation of single phase, L10 tetragonal, hard magnetic phase. Proton-induced X-ray emission spectroscopy PIXE has been utilized for checking the compositional effect of Mn addition. Structural properties were analyzed using X-ray diffraction and diffractograms were analyzed using full profile Rietveld-type analysis with MAUD (Materials Analysis Using Diffraction) software. By using temperature-dependent synchrotron X-ray diffraction, the disorder–order phase transformation and the stability of the hard magnetic L10 phase were monitored over a large temperature range (50–800 °C). A large interval of structural stability of the L10 phase was observed and this stability was interpreted in terms of higher ordering of the L10 phase promoted by the Mn addition. It was moreover found that both crystal growth and unit cell expansion are inhibited, up to the highest temperature investigated (800 °C), proving thus that the Mn addition stabilizes the formed L10 structure further. Magnetic hysteresis loops confirmed structural data, revealing a strong coercive field for a sample wherein single phase, hard, magnetic tetragonal L10 exists. These findings open good perspectives for use as nanocomposite, rare earth free magnets, working in extreme operation conditions.

Phase Equilibria and Solidification of Al-Rich Ai-Ui-Cu Alloys

1990 ◽  
Vol 186 ◽  
Author(s):  
Sinn-Wen Chen ◽  
Y. Austin Chang
Keyword(s):  
Liquidus Projection ◽  
Thermodynamic Description ◽  
Type Equation ◽  
Ternary Alloys ◽  
X Ray Diffraction ◽  
Thermodynamic Models ◽  
Isothermal Sections ◽  
X Ray ◽  
Cu Alloys ◽  
Calculated Amount

AbstractA liquidus projection of the Al-rich Al-Li-Cu system is proposed. The proposed liquidus projection was based on DTA, X-ray diffraction, metallography, EPMA, SEM, and chemical analysis of 50 ternary alloys. Using these data and those reported in the literature, and thermodynamic models of Al-Li, AI-Cu and Cu-Li, a thermodynamic description of the Al-rich AI-Li-Cu system was developed. The calculated isothermal sections at several temperatures and the liquidus projection are in agreement with the experimental determinations. Combining the thermodynamic models and a Scheil-type equation, quantitative solidification paths were described. The calculated amount of primary solidification phase was compared to the experimental determination.

Phase Decomposition in Cu-Ti Metallic Glass

1983 ◽  
Vol 28 ◽  
Author(s):  
R. D. Shull ◽  
S. P. Singhal ◽  
B. Mozer ◽  
A. Maeland
Keyword(s):  
Neutron Diffraction ◽  
Metallic Glass ◽  
Melt Spinning ◽  
Large Angle ◽  
Amorphous State ◽  
Glass Ribbon ◽  
Amorphous Structure ◽  
Phase Decomposition ◽  
X Ray ◽  
Diffraction Patterns

ABSTRACTA metallic glass ribbon of Cu55Ti45 prepared by melt spinning was examined by x-ray, neutron, and electron diffraction, by small angle neutron diffraction (SANS), transmission electron microscopy (TEM), and by differential thermal analysis (DTA). In the liquid quenched condition large angle diffraction data (both x-ray and neutron) show the broad banded structure typical of the amorphous state. The SANS data, however, exhibit highly anisotropic patterns arising from the phase decomposition during solidification. Ribbons annealed below the glass transition temperature (Tg ) produced neutron diffraction patterns of materials with the same amorphous structure combined with a new short range order; and the SANS patterns retained the asymmetry of the as-quenched material. Ribbons annealed above the crystallization temperature (Tc) show both isotropic and anisotropic contributions to the SANS patterns. Formation of the equilibrium TiCu phase occurs directly from the metallic glass at Tc. The equilibrium Ti3Cu4 phase, however, forms from the TiCu phase at slightly higher temperatures.

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