Alloying in an Immiscible Cu-Nb System upon Solid-State Reaction

ABSTRACTIn an immiscible Cu-Nb system, an amorphous alloy and two metastable crystalline phases were obtained by solid-state reaction of Cu-Nb multilayered films, and the formation of the alloy phases was found to be quite sensitive to the average composition of the films. At Nb concentration of 75at%, amorphization was achieved by 250°C annealing for 50 min, while in the films with compositions of 70 and 80 at% Nb, a simple cubic (a=0.405±0.005nm) and an orthorhombic phase (a=0.421, b=0.334, c=0.291±0.005nm) were observed, respectively. Thermodynamic calculation was conducted for the Nb-Cu alloy phases and the energetic state of the multilayers, which consisted of 9 Cu/Nb bilayers. It turned out that the excess free energy originating from the interfacial atoms could raise the multilayers to an energy level being higher than that of the amorphous or/and metastable crystalline phases both with a convex shape, and thus provided a major driving force for alloy phase formation in such immiscible system.

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Formation of metastable crystalline phases by solid state reaction in Ni-Nb multilayered films

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/32/2/001 ◽

1999 ◽

Vol 32 (2) ◽

pp. 79-83 ◽

Cited By ~ 2

Author(s):

G W Yang ◽

C Lin ◽

J B Liu ◽

B X Liu

Keyword(s):

Solid State ◽

Solid State Reaction ◽

Multilayered Films ◽

Crystalline Phases

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Magneto-optical spectroscopy study of the solid-state reaction in Ti/Ni multilayered films

Journal of Applied Physics ◽

10.1063/1.1287779 ◽

2000 ◽

Vol 88 (5) ◽

pp. 2430-2436 ◽

Cited By ~ 12

Author(s):

Y. V. Kudryavtsev ◽

V. V. Nemoshkalenko ◽

Y. P. Lee ◽

K. W. Kim ◽

C. G. Kim ◽

...

Keyword(s):

Solid State ◽

Optical Spectroscopy ◽

Solid State Reaction ◽

Spectroscopy Study ◽

Multilayered Films

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Structure and Dielectric Properties of Homogeneous Srm-3Bi4TimO3m+3 (m = 3, 4, 5, and 6) Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.133 ◽

2007 ◽

Vol 336-338 ◽

pp. 133-135 ◽

Cited By ~ 1

Author(s):

Wang Sheng Fang ◽

Pi Yi Du ◽

Wen Jian Weng ◽

Gao Rong Han

Keyword(s):

Dielectric Properties ◽

Solid State ◽

Curie Temperature ◽

Solid State Reaction ◽

Hysteresis Loops ◽

Reaction Process ◽

Conventional Solid State Reaction ◽

Crystalline Phases ◽

Impedance Analyzer ◽

Phase Structures

Srm-3Bi4TimO3m+3 (m =3, 4, 5, and 6) bulk ceramics were prepared by conventional solid-state reaction process. Their phase structures and morphologies were observed by XRD and SEM respectively. The dielectric properties and hysteresis loops of the ceramics were measured by impedance analyzer and hysteresis meter respectively. Results showed that the lattice parameters along the c axis are 32.79, 41.11, 48.83, and 58.17Ǻ for m=3, 4, 5, and 6 respectively. The microstructures of plate-like crystalline phases are shown in all the ceramics with different m. Curie temperature of Srm-3Bi4TimO3m+3 decreases from 668°C to 295°C with increasing m from 3 to 6. The remnant polarizations Pr are 32.46 and 19.44 μC/cm2 for odd m of 3 and 5, and 11.84 and 10.58 μC/cm2 for even m of 4 and 6 respectively.

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SOLID-STATE REACTION OF Zr-Fe MULTILAYERED FILMS INVESTIGATED BY MÖSSBAUER SPECTROSCOPY

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1990418 ◽

1990 ◽

Vol 51 (C4) ◽

pp. C4-157-C4-162

Author(s):

C. MICHAELSEN ◽

M. PIEPENBRING ◽

H. U. KREBS

Keyword(s):

Mössbauer Spectroscopy ◽

Solid State ◽

Solid State Reaction ◽

Mossbauer Spectroscopy ◽

Multilayered Films ◽

Mößbauer Spectroscopy

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Al-Yb Amorphous Alloys Produced by Ion Mixing or Solid State Reaction

MRS Proceedings ◽

10.1557/proc-235-521 ◽

1991 ◽

Vol 235 ◽

Cited By ~ 1

Author(s):

B. X. Liu ◽

J. R. Ding ◽

D. Z. Che ◽

H. B. Zhang

Keyword(s):

Solid State ◽

Solid State Reaction ◽

Amorphous Alloys ◽

Room Temperature ◽

Composition Range ◽

Metastable Phase ◽

Recrystallization Behavior ◽

Multilayered Films ◽

The Difference ◽

Hcp Structure

ABSTRACTWe report, in this paper, three different ways of producing amorphous alloys in the Al-Yb system, (i) Al80Yb20multilayered films were readily amorphized by 180 keV xenon ion mixing at room temperature(RT) to a dose of 3×1015 Xe/cm2. (ii) When the dose went up to 1×1016 Xe/cm2 or higher, a metastable phase of hcp structure was formed. Interestingly, the hcp phase turned into amorphous after annealing at 500°C for about 10 minutes. (iii) Amorphous alloys were also formed by steady state thermal annealing of the Al-Yb multilayered films at about 450 °C for 20 minutes. The optimum amorphization range was found out by experiments to be 17 to 30 Yb at%, i.e., within this composition range, the multilayered films could entirely be amorphized by solid state reaction.The recrystallization behavior of the amorphous alloys formed by different methods was also studied and the difference in this aspect was thought to relate to the structures resulting from different processing methods.Possible explanation of the observed sequence of phase transition is also discussed.

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