Structure and Properties of Germanium Carbide Films Prepared by RF Reactive Sputtering inAr/CH4

Nonhydrogen germanium carbide (GexC[Formula: see text]) films were prepared by KrF pulsed lasers deposition (PLD), and the effects of different germanium contents on the microstructures, optical properties and adhesion properties of the GexC[Formula: see text] films were studied. XRD measurements showed that the GexC[Formula: see text] films with different germanium contents were of amorphous structure. XPS analysis showed that the C/Ge atomic ratios of GexC[Formula: see text] films were close to those of corresponding targets. The intensity of Ge3[Formula: see text] peak in the GexC[Formula: see text] films increased and the intensity of C1s peak decreased with the increase of the germanium content. The GexC[Formula: see text] films’ [Formula: see text]C bond contents increased from 46.4% to 69.7%. Ellipsometry and infrared transmission spectral measurements showed that the refractive index of GexC[Formula: see text] films increased from 2.5 to 3.5 at the wavelength of 1[Formula: see text][Formula: see text]m with the increase of germanium content. The extinction coefficient of GexC[Formula: see text] film was of the order of 10[Formula: see text] in the infrared band when the germanium content was less than 10[Formula: see text]at.%. The adhesion tests showed that the adhesion performances of GexC[Formula: see text] films were better when the germanium content increased.

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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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