Structure of Amorphous Phase and Nanocrystalline Phases in the Devitrification of Iron Alloys

N. B. D’yakonova; D. L. D’yakonov; B. A. Kornienkov; V. P. Filippova

doi:10.3103/s096709121905005x

Nanocrystalline Ni-Mo alloys and their application in electrocatalysis

Journal of Materials Research ◽

10.1557/jmr.1994.2998 ◽

1994 ◽

Vol 9 (11) ◽

pp. 2998-3008 ◽

Cited By ~ 48

Author(s):

R. Schulz ◽

J.Y. Huot ◽

M.L. Trudeau ◽

L. Dignard-Bailey ◽

Z.H. Yan ◽

...

Keyword(s):

Solid Solution ◽

Hydrogen Evolution ◽

Amorphous Phase ◽

Hydrogen Evolution Reaction ◽

Supersaturated Solid Solution ◽

Milling Process ◽

Alkaline Solutions ◽

Nanocrystalline State ◽

Mo Content ◽

Nanocrystalline Phases

The structural and electrocatalytic properties of metastable Ni-Mo alloys have been investigated for the hydrogen evolution reaction in alkaline solutions. Amorphous and nanocrystalline phases have been prepared by mechanically alloying the elemental components under various milling conditions. Fcc nanocrystals are formed when the Mo concentration is smaller than 30 at. %. The nanocrystalline state becomes unstable with respect to the amorphous phase when the Mo content in the solid solution exceeds 30 at. %. The electroactive phase for the hydrogen evolution reaction in alkaline solutions is the nanocrystalline supersaturated solid solution. The presence of oxygen during the milling process improves the properties of the alloys.

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Investigations on in situ Nanocrystallization and Magnetic Properties for Amorphous Fe78Si9B13 Ribbons

MRS Proceedings ◽

10.1557/proc-562-301 ◽

1999 ◽

Vol 562 ◽

Cited By ~ 2

Author(s):

Xiangcheng Sun ◽

A. Cabral-Prieto ◽

M. Jose Yacaman ◽

Wensheng Sun

Keyword(s):

Amorphous Phase ◽

Annealing Temperature ◽

Amorphous State ◽

Field Pattern ◽

Transmission Electron ◽

Optimum Annealing Temperature ◽

Differential Scanning Calorimeters ◽

Nanocrystalline Phases ◽

Good Agreement

ABSTRACTThe amorphous state of ferromagnetic Fe78Si9B13 (Metglas 2605S-2) and itsnanocrystallization were investigated by in situ transmission electron microscope (TEM), Xraydiffraction (XRD), Mossbauer spectroscopy (MS), differential scanning calorimeters(DSC) and magnetic moment measurements. The Mössbauer spectrum exhibited anessentially symmetric hyperfine field pattern of 259KOe in as-quenched amorphous state atroom temperature. The Curie and crystallization temperature were determined to beTc=708K and Tx.= 803K, respectively. The Tx value was in good agreement with DSCmeasurement results. The occupied fraction of the nanocrystalline phases of α-Fe(Si) andFe2 at in situ optimum annealing temperature was about 57% and 43%, respectively. It isnotable that the magnetization of the amorphous phase decreases more rapidly withincreasing temperature than those of nanocrystalline ferromagnetism, suggesting thepresence of the distribution of exchange interaction in the amorphous phase or highmetalloid contents.

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Investigations On In Situ Nanocrystallization And Magnetic Properties For Amorphous Fe78Si9B13 Ribbons

MRS Proceedings ◽

10.1557/proc-577-617 ◽

1999 ◽

Vol 577 ◽

Author(s):

Xiangeheng Sun ◽

A. Cabral-Prieto ◽

M. Jose Yacaman ◽

Wensheng Sun

Keyword(s):

Amorphous Phase ◽

Amorphous State ◽

Field Pattern ◽

Transmission Electron ◽

Measurement Results ◽

Optimum Annealing Temperature ◽

Increasing Temperature ◽

Differential Scanning Calorimeters ◽

Nanocrystalline Phases

ABSTRACTThe amorphous state of ferromagnetic Fe78Si9B13 (Metglas 2605S-2) and its nanocrystallization were investigated by in situ transmission electron microscope (TEM), Xray diffraction (XRD), Mossbauer spectroscopy (MS), differential scanning calorimeters (DSC) and magnetic moment measurements. The Mössbauer spectrum exhibited an essentially symmetric hyperfine field pattern of 259KOe in as-quenched amorphous state at room temperature. The Curie and crystallization temperature were determined to be Tc=708K and Tx= 803K, respectively. The Tx value was in good agreement with DSC measurement results. The occupied fraction of the nanocrystalline phases of α-Fe(Si) and Fe2B at in situ optimum annealing temperature was about 57% and 43%, respectively. It is notable that the magnetization of the amorphous phase decreases more rapidly with increasing temperature than those of nanocrystalline ferromagnetism, suggesting the presence of the distribution of exchange interaction in the amorphous phase or high metalloid contents.

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AMORPHOUS/NANOCRYSTALLIZATION OF TiN-TiB2 REINFORCED LASER CLAD COMPOSITES

Surface Review and Letters ◽

10.1142/s0218625x19500574 ◽

2019 ◽

Vol 26 (09) ◽

pp. 1950057

Author(s):

MOLIN SU ◽

JIANING LI ◽

XUEGANG WANG ◽

ZHIYUAN LIU

Keyword(s):

Wear Resistance ◽

Liquid Metal ◽

Amorphous Phase ◽

Laser Cladding ◽

Substrate Surface ◽

Reinforced Composites ◽

Alloy Substrate ◽

Nanocrystalline Phases

Laser cladding (LC) of the Stellite6-BN-Cu-Y2O3 pre-placed powders on the Ti-6Al-4V alloy substrate formed the bulk TiN and needle-like Ti-B compounds reinforced composites, which improved the wear resistance of the substrate surface. The results showed that lots of the amorphous-nanocrystalline phases were produced in such composites; the proper content of Cu was used to refine microstructures, also a large number of the nanocrystals can be formed; the elements such as Co, Ni and Fe in Stellite6 favored the amorphous phase to be formed. The addition of Y2O3 improved the fluidity of the liquid metal, also retarding the growth of the dendrite, leading the fine microstructures to be formed, improving the property of the LC composites.

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