Reversible Structural Relaxation in Fe-Ni-B-Si Metallic Glasses

1986 ◽  
Vol 80 ◽  
Author(s):  
R. Brüning ◽  
Z. Altounian ◽  
J. O. Ström-Olsen
Keyword(s):  
Metallic Glasses ◽  
Structural Relaxation ◽  
Short Range ◽  
Short Range Order ◽  
Composition Dependence ◽  
Published Data ◽  
Surface Crystallization ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray

AbstractReversible structural relaxation has been studied in (Fe1-xNix)80B10Si10 by differential scanning calorimetry and X-ray diffraction. It is found that surface crystallization plays a major role in inhibiting reversibility. In consequence previously published data have presented a misleading picture about the composition dependence of the reversible effect in Fe-Ni-B-Si, which simply increases monotonically with Ni composition. There is no evidence that chemical short range order plays any role in reversibility.

Long- and short-range order in the Ni52Co2Fe20Ga26 ferromagnetic Heusler alloy

2021 ◽  
Vol 54 (4) ◽  
Author(s):  
Dan Macovei ◽  
Felicia Tolea
Keyword(s):  
Heusler Alloy ◽  
Short Range ◽  
Melt Spinning ◽  
Short Range Order ◽  
High Energy ◽  
Range Order ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Austenitic Phase ◽  
X Ray

The crystalline structure and Fe local environment in a Co-doped Ni–Fe–Ga Heusler alloy, prepared by the melt-spinning technique, were investigated by X-ray diffraction (XRD) and EXAFS at room and low temperatures. The characteristic temperatures of the austenite–martensite phase transitions were determined by differential scanning calorimetry via cooling and heating cycles of the alloy ribbons. As shown by room-temperature XRD, the austenitic phase of the alloy has the chemically ordered L21 Heusler structure. This was confirmed by EXAFS, although this technique was not able to conclusively distinguish between the L21 and B2 structures of the austenite for the analyzed alloy. The low-temperature martensitic phase and its structural evolution towards austenite with increasing temperature were studied by high-energy X-ray diffraction, which evinced the martensite modulation. However, the Fe environment could be fitted by EXAFS with the tetragonal L10 structure of the non-modulated martensite. This proves that the martensite modulation has structural effects on a long-range scale, without significant changes in the short-range order around the atoms. The changes in the local structure around iron on martensitic transformation were correlated with changes in the electronic structure, described by XANES spectroscopy at the Fe K edge.

Short-range order in some alloys of the Ge-As-Te semiconducting glassy system by X-ray diffraction

1987 ◽  
Vol 22 (12) ◽  
pp. 4357-4361 ◽  
Author(s):  
R. A. Ligero ◽  
J. Vázquez ◽  
P. Villares ◽  
R. Jimńez-Garay
Keyword(s):  
Short Range ◽  
Short Range Order ◽  
Range Order ◽  
X Ray Diffraction ◽  
Glassy System ◽  
X Ray

Short-range order in some polymer melts from X-ray diffraction

1996 ◽  
Vol 34 (17) ◽  
pp. 3055-3061 ◽  
Author(s):  
J. D. Londono ◽  
A. Habenschuss ◽  
J. G. Curro ◽  
J. J. Rajasekaran
Keyword(s):  
Short Range ◽  
Short Range Order ◽  
Polymer Melts ◽  
Range Order ◽  
X Ray Diffraction ◽  
X Ray

scholarly journals X-ray diffraction study of structure of CaO-Al2O3-SiO2 ternary compounds in molten and crystalline states

2020 ◽  
Vol 56 (2) ◽  
pp. 269-277
Author(s):  
V.E. Sokol’skii ◽  
D.V. Pruttskov ◽  
O.M. Yakovenko ◽  
V.P. Kazimirov ◽  
O.S. Roik ◽  
...  
Keyword(s):  
Short Range ◽  
Room Temperature ◽  
Short Range Order ◽  
Structural Parameters ◽  
Range Order ◽  
Reverse Monte Carlo ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Ternary Compounds

Anorthite and gehlenite crystalline structure and short-range order of anorthite melt have been studied by X-ray diffraction in the temperature range from room temperature up to ~ 1923 K. The corresponding anorthite and gehlenite phases were identified as well as amorphous component for anorthite samples having identical shape to XRD pattern of the anorthite melt. The structure factor and the radial distribution function of atoms of the anorthite melt were calculated from the X-ray high-temperature experimental data. The partial structural parameters of the short-range order of the melt were reconstructed using Reverse Monte Carlo simulations.

Structure Investigations on Se1-xTex Melts by Neutron Scattering and X-ray Diffraction

1981 ◽  
Vol 36 (8) ◽  
pp. 880-885 ◽  
Author(s):  
W. Hoyer ◽  
B. Kunsch ◽  
M. Suda ◽  
E. Wieser
Keyword(s):  
Correlation Function ◽  
Neutron Scattering ◽  
Diffraction Data ◽  
Short Range ◽  
Short Range Order ◽  
Range Order ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nearest Neighbours ◽  
Structure Investigations

Abstract Neutron scattering results on Se1-xTex melts (x = 0.3, 0.6, 0.8) obtained at 460 °C are combined with earlier X-ray diffraction data. The behaviour of the number and distance of nearest neighbours is discussed with respect to chemical short-range order and transition from twofold to three-fold coordination. For Se70Te30 the radial concentration correlation function 4πr2 ρcc(r) has been evaluated. It shows clearly the preferred formation of unlike pairs (Se-Te) within the chains.

Comparison of the Thermal Stabilities of Amorphous Hydrides Formed by Zr-Based Metallic Glasses

1986 ◽  
Vol 80 ◽  
Author(s):  
J. S. Cantrell ◽  
R. C. Bowman
Keyword(s):  
Metallic Glasses ◽  
Intermetallic Phases ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Thermal Stabilities ◽  
X Ray ◽  
Decomposition Reactions ◽  
Free Metal ◽  
Metal Ratios ◽  
Approach Unity

AbstractDifferential scanning calorimetry (DSC) and x-ray diffraction (XRD) measurements were performed on a-Zr2 PdHx, a-Zr3 RhHx, a-Zr76 Fe24 Hx, and a- Zr2NiHx to assess the effects of hydrogen on their thermal stabilities. Only exothermic DSC peaks were observed for the hydrogen-free glasses and are shown to correspond to the formation of crystalline intermetallic phases. On the other hand, heating of the amorphous hydrides gives decomposition reactions with the generation of ZrHx (1.5 <x < 2.0) and either free metal (e.g., Rh) or a Zr-depleted intermetallic (e.g., ZrPd). With the exception of the Zr2 PdHx samples, hydrogenation significantly decreases the thermal stabilities (i.e., the exothermic transitions occur at lower temperatures in the amorphous hydrides). Endothermic peaks, which are associated with hydrogen evolution from the glass, are observed when the hydrogen-to-metal ratios approach unity.

X-Ray Diffraction Study of Atomic Short-Range Order in Pt–15.0 at.% Cr Alloy

2002 ◽  
Vol 71 (10) ◽  
pp. 2456-2458 ◽  
Author(s):  
Dilip Kumar Saha ◽  
Toetsu Shishido ◽  
Ken-ichi Ohshima
Keyword(s):  
Diffraction Study ◽  
Short Range ◽  
Short Range Order ◽  
Range Order ◽  
X Ray Diffraction ◽  
X Ray

Noncrystalline Solids Prepared by Compacting Nanometer — Sized Particles

1990 ◽  
Vol 195 ◽  
Author(s):  
J. Weissmüller ◽  
J. Jing ◽  
A. Krämer ◽  
R. Birringer ◽  
U. Gonser ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Atomic Structure ◽  
Short Range ◽  
Short Range Order ◽  
Amorphous Solids ◽  
Range Order ◽  
New Method ◽  
X Ray Diffraction ◽  
X Ray

ABSTRACTA new method of preparing amorphous solids is presented. X-ray diffraction, thermal stability and Mgssbauer spectroscopy give evidence for an atomic structure with reduced short–range order in Si75Auz5 and Pd72FeloSil8 alloys prepared by this method.

Ti Microalloying Effect on Corrosion Resistance and Thermal Stability of Cu45Zr48Al7 Bulk Metallic Glass

2012 ◽  
Vol 490-495 ◽  
pp. 3868-3873 ◽  
Author(s):  
Xiao Hong Yang ◽  
Xi Peng Nie ◽  
Jian Zhong Jiang
Keyword(s):  
Thermal Stability ◽  
Corrosion Resistance ◽  
Metallic Glasses ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Glass Forming ◽  
Ti Addition ◽  
Mould Casting ◽  
Thermal Stability Of

Bulk metallic glasses (BMGs) of Cu45Zr48-xAl7Tix with x= 0, 1.5, and 3 at.% were prepared by copper mould casting. The corrosion resistance of the BMGs with different Ti contents was examined by potentiodynamic polarization tests and weight loss measurements in 1 N NaOH, 1 N H2SO4, 1 N H2SO4 + 0.01 N NaCl and 0.5 N NaCl solutions, respectively. The newly-developed BMGs’ corrosion resistance in Cl-- or both H+ and Cl--ions containing solutions can be greatly enhanced. The influence of Ti addition on glass forming ability (GFA) and thermal stability was investigated by x-ray diffraction and differential scanning calorimetry in detail. The alloy containing 1.5 at.% Ti exhibits the largest GFA, the critical size comes up to 10 mm in diameter.

scholarly journals Investigation of short-range structural order in Zr69.5Cu12Ni11Al7.5and Zr41.5Ti41.5Ni17glasses, using X-ray absorption spectroscopy andab initiomolecular dynamics simulations

2014 ◽  
Vol 21 (6) ◽  
pp. 1296-1304 ◽  
Author(s):  
Debdutta Lahiri ◽  
Surinder M. Sharma ◽  
Ashok K. Verma ◽  
B. Vishwanadh ◽  
G. K. Dey ◽  
...  
Keyword(s):  
Absorption Spectroscopy ◽  
Metallic Glasses ◽  
Short Range ◽  
Short Range Order ◽  
Relative Importance ◽  
Chemical Order ◽  
X Ray ◽  
Glass Forming ◽  
Dynamics Simulations ◽  
X Ray Absorption

Short-range order has been investigated in Zr69.5Cu12Ni11Al7.5and Zr41.5Ti41.5Ni17metallic glasses using X-ray absorption spectroscopy andab initiomolecular dynamics simulations. While both of these alloys are good glass formers, there is a difference in their glass-forming abilities (Zr41.5Ti41.5Ni17> Zr69.5Cu12Ni11Al7.5). This difference is explained by inciting the relative importance of strong chemical order, icosahedral content, cluster symmetry and configuration diversity.

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