Unusual Vortex Motion in the Quantum-Liquid Phase of Amorphous Films

AbstractEpitaxial BiFeO3 (BFO) thick films were fabricated on SrTiO3 (STO) substrates by a simple liquid-phase epitaxy (LPE) growth technique. To avoid the evaporation of Bi, in this process, we used the lid substrate. As starting materials, we used calcined powder or amorphous films deposited by pulsed laser ablation. The fabricated films were found to have a single perovskite phase and be (100)-oriented. Cube-on-cube epitaxial growth of film on the STO substrate was also confirmed by ϕ-scan measurements. The films grown on the substrate display a multigrain structure with a maximum in-plane size of approximately 100μm, and the film thickness was about 3-35 μm. The interface structure between the film and the substrate was relatively smooth. These results indicate that the proposed simple LPE technique is highly suitable for the fabrication of BFO thick films.

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AEM analysis of crystallization in Ti-based amorphous alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075142 ◽

1983 ◽

Vol 41 ◽

pp. 270-271

Author(s):

A.R. Pelton ◽

A.F. Marshall ◽

Y.S. Lee

Keyword(s):

Magnetic Properties ◽

Amorphous Alloys ◽

Amorphous Materials ◽

Isothermal Annealing ◽

Amorphous Matrix ◽

Nucleation And Growth ◽

Current Interest ◽

Amorphous Films ◽

Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

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Elucidation of block boundaries as the dissolution channels in hydrated cement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109562 ◽

1978 ◽

Vol 36 (1) ◽

pp. 484-485

Author(s):

N.V. Belov ◽

U.I. Papiashwili ◽

B.E. Yudovich

Keyword(s):

Liquid Phase ◽

Grain Boundaries ◽

Benzoyl Peroxide ◽

Phase Contrast ◽

Active Role ◽

Point Of View ◽

Hardened Cement ◽

Hydrated Cement ◽

Hardened Cement Paste

It has been almost universally adopted that dissolution of solids proceeds with development of uniform, continuous frontiers of reaction.However this point of view is doubtful / 1 /. E.g. we have proved the active role of the block (grain) boundaries in the main phases of cement, these boundaries being the areas of hydrate phases' nucleation / 2 /. It has brought to the supposition that the dissolution frontier of cement particles in water is discrete. It seems also probable that the dissolution proceeds through the channels, which serve both for the liquid phase movement and for the drainage of the incongruant solution products. These channels can be appeared along the block boundaries.In order to demonsrate it, we have offered the method of phase-contrast impregnation of the hardened cement paste with the solution of methyl metacrylahe and benzoyl peroxide. The viscosity of this solution is equal to that of water.

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