Oxygen Distribution in Zr-Based Metallic Glasses

AbstractThis paper reports the atom probe analysis results of the oxygen dissolved in the as-cast amorphous and crystallized Zr65Cu15Al10Pd10 and Zr65Cul17.5Ni10Al17.5 alloys. Impurity oxygen ranging from 0.1 to 1 at.% is dissolved uniformly in the as-quenched Zr65Cu15A110Pd10 and Zr65Cu17.5Ni10Al7.5 amorphous alloys even though the oxygen is not added intentionally. When the Zr65Cu15Al10Pd10 alloy is crystallized, oxygen redistribution occurs; it is rejected from the primary Zr2 (Cu, Pd) crystals and partitioned in the subsequently crystallized phases. Oxygen atoms are enriched in some of the crystalline phases up to approximately 4 at.%, and virtually no oxygen is dissolved in the remaining amorphous phase. In the partially crystallized Zr65Cu17.5Ni10Al7.5 alloy, fine oxygen enriched particles containing ∼ 15 at.%O have been detected in direct contacted with crystalline grains. This work demonstrates that oxygen redistribution occurs during the crystallization reaction, thereby influencing the kinetics of crystallization.

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Роль переходных металлов в кристаллизации аморфных сплавов Al-Ni-Co-Yb

Журнал технической физики ◽

10.21883/jtf.2019.10.48174.71-19 ◽

2019 ◽

Vol 89 (10) ◽

pp. 1571

Author(s):

Б.А. Русанов ◽

В.Е. Сидоров ◽

P. Svec ◽

P. Svec Sr. ◽

D. Janickovic

Keyword(s):

Amorphous Phase ◽

Heating Rates ◽

Casting Method ◽

Planar Flow ◽

X Ray ◽

Kinetics Of Crystallization ◽

Amorphous Ribbons ◽

Wide Interval ◽

Planar Flow Casting ◽

Kinetics Of

Amorphous ribbons of Al86Ni4Co4Yb6 and Al86Ni6Co2Yb6 compositions were produced by a standard planar flow casting method. According to the X-ray analysis, the as-cast ribbons were amorphous. Kinetics of crystallization and electroresistivity were studied with different heating rates. Alloys have a wide interval of amorphous phase, and the different combination of transitions metals influence on process of their crystallization.

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Specific Features of Structure Transformation and Properties of Amorphous-Nanocrystalline Alloys

Metals ◽

10.3390/met10030358 ◽

2020 ◽

Vol 10 (3) ◽

pp. 358 ◽

Cited By ~ 1

Author(s):

Alexandr Aronin ◽

Galina Abrosimova

Keyword(s):

Amorphous Phase ◽

Metallic Glasses ◽

Amorphous Alloys ◽

Structural Changes ◽

Shear Bands ◽

Component Composition ◽

Amorphous Structure ◽

Structure Evolution ◽

Current State ◽

Heterogeneous Phase

This work is devoted to a brief overview of the structure and properties of amorphous-nanocrystalline metallic alloys. It presents the current state of studies of the structure evolution of amorphous alloys and the formation of nanoglasses and nanocrystals in metallic glasses. Structural changes occurring during heating and deformation are considered. The transformation of a homogeneous amorphous phase into a heterogeneous phase, the dependence of the scale of inhomogeneities on the component composition, and the conditions of external influences are considered. The crystallization processes of the amorphous phase, such as the homogeneous and heterogeneous nucleation of crystals, are considered. Particular attention is paid to a volume mismatch compensation on the crystallization processes. The effect of changes in the amorphous structure on the forming crystalline structure is shown. The mechanical properties in the structure in and around shear bands are discussed. The possibility of controlling the structure of fully or partially crystallized samples is analyzed for creating new materials with the required physical properties.

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Kinetics of crystallization of FeB-based amorphous alloys studied by neutron thermo-diffractometry

Journal of Non-Crystalline Solids ◽

10.1016/j.jnoncrysol.2006.12.091 ◽

2007 ◽

Vol 353 (8-10) ◽

pp. 855-858 ◽

Cited By ~ 14

Author(s):

A. Fernández-Martinez ◽

P. Gorría ◽

G.J. Cuello ◽

J.D. Santos ◽

M.J. Pérez

Keyword(s):

Amorphous Alloys ◽

Kinetics Of Crystallization ◽

Kinetics Of

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APFIM Studies of Nanocrystallizations of Amorphous Alloys

MRS Proceedings ◽

10.1557/proc-400-203 ◽

1995 ◽

Vol 400 ◽

Author(s):

K. Hono ◽

Y. Zhang ◽

A. Inoue ◽

T. Sakurai

Keyword(s):

Amorphous Alloys ◽

Amorphous Matrix ◽

Primary Crystallization ◽

Atom Probe ◽

Nucleation And Growth ◽

Cu Alloy ◽

Nucleation Sites ◽

Medium Range ◽

Crystallization Reaction ◽

Primary Crystals

AbstractThis paper reports recent atom probe analysis results of Fe-Zr-B(-Cu) and Al-Ni-Ce(-Cu) amorphous alloys, in which nanocrystalline microstructures develop by primary crystallization. In these alloy systems, enrichment of slow diffusing solute was found at the interfaces between primary crystals and amorphous matrix during the nucleation and growth stage. In the case of ternary Fe-Zr-B, no evidence for compositional heterogeneities were found prior to the onset of crystallization reaction. On the other hand, clustering of Cu atoms was observed in quaternary Fe-Zr-B-Cu alloy prior to the crystallization reaction. In the ternary Fe-Zr-B alloy, nucleation sites seem to be provided by the quenched-in nuclei which were observed as medium range ordered (MRO) domains by HREM. In the as-quenched Al-Ni-Ce(-Cu) alloy, compositional fluctuations were present from the as-quenched state. These observations suggest that nuclei for primary crystallization are provided in various forms such as MRO domains, solute clusters and compositional heterogeneities.

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Effect of Cu On Microstructural Evolution of Nanocrystalline Soft and Hard Magnetic Materials

MRS Proceedings ◽

10.1557/proc-577-507 ◽

1999 ◽

Vol 577 ◽

Cited By ~ 3

Author(s):

K. Hono ◽

D. H. Ping ◽

S. Hirosawa

Keyword(s):

Amorphous Alloys ◽

Three Dimensional ◽

Atom Probe ◽

Hard Magnetic Materials ◽

Atom Clusters ◽

Transmission Electron ◽

Nucleation Sites ◽

Final Microstructure ◽

Crystallization Reaction ◽

Primary Crystals

ABSTRACTThe nanocrystallization processes in Fe-Si-B-Nb-Cu and Fe-Nd-B(-Cu-Nb) amorphous alloys have been studied by transmission electron microscopy (TEM) and a three dimensional atom probe (3DAP). Cu additions are effective in refining the nanocrystalline microstructures of both alloys, because Cu atom clusters formed prior to the crystallization reaction serve as heterogeneous nucleation sites for the primary crystals. However, the clustering behaviors of Cu atoms in these two alloy systems are different, i.e., Cu completely dissolves in the Nd2Fe1 4B phase in the final microstructure of the Nd4.5Fe75.8B18.5Cu0.2Nb1 alloy, whereas CL' clusters grow to fcc-Cu particles in the Fe73.5Si13.5B9Nb3Cu1 alloy. The nanocrystallization processes in these two alloys clarified by the 3DAP results are compared.

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Amorphous alloys and differential scanning calorimetry (DSC)

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-021-11054-0 ◽

2021 ◽

Author(s):

Dora Janovszky ◽

Maria Sveda ◽

Anna Sycheva ◽

Ferenc Kristaly ◽

Ferenc Zámborszky ◽

...

Keyword(s):

Metallic Glasses ◽

Amorphous Alloys ◽

Volume Fraction ◽

Data Interpretation ◽

Glass Temperature ◽

Scanning Calorimetry ◽

Scientific Papers ◽

Kinetics Of ◽

Temperature Crystallization

AbstractA remarkable number of scientific papers are available in the literature about the bulk amorphous alloys and metallic glasses. Today, DSC is an essential tool for amorphous alloys research and development, and of course for quality assurance. In many cases, users seek to examine the determination of only one or two properties, although much more information can be obtained from the measurements. The research involved structural relaxation, Curie temperature, glass temperature, crystallization, phase separation, nanocrystalline volume fraction, melting point and liquidus temperature determination subjects and kinetics of microstructural transformations induced by thermal treatment. We collected and present the information that can be obtained with this technique and draws the reader’s attention to some potential problems related to data interpretation.

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