The Nanocrystalline Alloys: The Structure and Properties

Abstract Amorphous precursors of A: (Fe64Co21B15)95P4Cu1 and B: (Fe64Co21B15)96P4 alloys were used. Nanocrystalline structure was created by heat treatment. Samples were studied by Mössbauer spectroscopy, XRD and AFM. Cu ions of dose 1016 at/cm2 were implanted into the amorphous B. According to simulated program we estimated that Cu ions created surface layer with a thickness of a few micrometres. Changes in bulk structure were not observed at parameters of Mössbauer spectra after implantation. After heat treatment the implanted sample was nearly identical with the nanocrystalline sample of A. Implantation had an influence on the volumetric fraction of the constituent phases and on their magnetic microstructure. Implantation of Cu ions in amorphous precursor containing Cu as A caused after heat treatment in nanocrystalline state increasing of nanocrystalline component. This technology of preparation of nanocrystalline alloys indicate that implantation of ions into an amorphous precursor has an influence on the final structure and properties of nanocrystalline alloy.

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Structure of second phases in TiAl alloys containing Cr and B

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087197 ◽

1991 ◽

Vol 49 ◽

pp. 576-577

Author(s):

Ernest L. Hall ◽

Shyh-Chin Huang

Keyword(s):

Grain Size ◽

Second Phase ◽

Structure And Properties ◽

Tial Alloys ◽

Second Phases ◽

Interstitial Elements

Addition of interstitial elements to γ-TiAl alloys is currently being explored as a method for improving the properties of these alloys. Previous work in which a number of interstitial elements were studied showed that boron was particularly effective in refining the grain size in castings, and led to enhanced strength while maintaining reasonable ductility. Other investigators have shown that B in γ-TiAl alloys tends to promote the formation of TiB2 as a second phase. In this study, the microstructure of Bcontaining TiAl alloys was examined in detail in order to describe the mechanism by which B alters the structure and properties of these alloys.

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Relationships between hierarchical structure and properties in macromolecular systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126950 ◽

1987 ◽

Vol 45 ◽

pp. 440-443

Author(s):

E. Baer

Keyword(s):

Uniaxial Tension ◽

Hierarchical Structure ◽

Inorganic Material ◽

Hierarchical Structures ◽

Bone Collagen ◽

Structure And Properties ◽

Connective Tissues ◽

Scale Level ◽

Fibrous Protein ◽

Macromolecular Systems

The most advanced macromolecular materials are found in plants and animals, and certainly the connective tissues in mammals are amongst the most advanced macromolecular composites known to mankind. The efficient use of collagen, a fibrous protein, in the design of both soft and hard connective tissues is worthy of comment. Very crudely, in bone collagen serves as a highly efficient binder for the inorganic hydroxyappatite which stiffens the structure. The interactions between the organic fiber of collagen and the inorganic material seem to occur at the nano (scale) level of organization. Epitatic crystallization of the inorganic phase on the fibers has been reported to give a highly anisotropic, stress responsive, structure. Soft connective tissues also have sophisticated oriented hierarchical structures. The collagen fibers are “glued” together by a highly hydrated gel-like proteoglycan matrix. One of the simplest structures of this type is tendon which functions primarily in uniaxial tension as a reinforced elastomeric cable between muscle and bone.

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The Structure and Properties of MoSi2 Thin Film in Mos Process

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001379 ◽

1980 ◽

Vol 38 ◽

pp. 326-327

Author(s):

C.K. Wu ◽

P. Chang ◽

N. Godinho

Keyword(s):

Thin Film ◽

Integrated Circuits ◽

High Performance ◽

Large Scale ◽

Process Development ◽

Structure And Properties ◽

Metal Silicides ◽

High Oxidation ◽

Important Approach ◽

High Oxidation Resistance

Recently, the use of refractory metal silicides as low resistivity, high temperature and high oxidation resistance gate materials in large scale integrated circuits (LSI) has become an important approach in advanced MOS process development (1). This research is a systematic study on the structure and properties of molybdenum silicide thin film and its applicability to high performance LSI fabrication.

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