Transformation of graphite islets on the surface of recrystallized platinum foil under the action of mechanical loading

The effect of uniaxial tension on the behavior of graphite segregates (islets) on the surface of recrystallized platinum foil is studied in situ by low-energy electron diffraction and Auger electron spectroscopy. Mechanical stresses are shown to have a significant influence on the size and orientation of the islets. The alignment of the islets along steps on the platinum surface is discovered.     

Energy criterion for relief formation on a strained surface

The strain-induced roughening revealed by scanning tunneling microscopy on the surface of elastically strained Ge(111) crystals and Fe₇₀Cr₁₅B₁₅ amorphous alloy foils is discussed. It is demonstrated that the strained-induced roughening can be considered a channel for a decrease in the elastic energy of the strained surface. The diffusion mechanism of relief formation on a strained Ge(111) surface is proposed and justified.     

Mechanism of submicrocrack generation in stressed polymers

Submicrocracks, free radicals, and endgroups of scissioned molecules formed in polyethylene, polypropylene, and polycaprolactam under uniaxial tension have been investigated. Measurements were carried out by small-angle x-ray scattering, electron paramagnetic resonance, and infrared spectroscopy. The concentration of submicrocracks is almost the same as that of free radicals but is smaller than the concentration of scissioned macromolecules by approximately three orders of magnitude. The number of scissions per crack proved to be close to the number of macromolecules passing through the cross section of a submicrocrack calculated on the assumption of close packing. It is concluded that submicrocracks in stressed polymers are formed as a result of chain reactions of macromolecular decomposition initiated by the active end primary free radicals.     

Dependence of the atomic structure and surface relief of platinum foils on the annealing and rolling conditions

The effect of cold rolling, polishing, and thermal annealing conditions on the atomic structure and surface geometry of platinum foils has been studied. The surface morphology has been analyzed using low-energy electron diffraction, atomic force microscopy, and scanning tunneling microscopy. The chemical composition of the surface has been evaluated by Auger electron spectroscopy. It has been demonstrated that a variation in the conditions used for the preparation of the samples makes it possible to produce surfaces with different degrees of perfection from atomically smooth to rippled, fractal, and diffraction-disordered surfaces.     

The Influence of Mechanical Treatment on the Surface Relief of a Fe77Ni1Si9B13 Metal Glass

Physics of the Solid State - The micro- and nanoreliefs of the loaded surfaces of a Fe77Ni1Si9B13 metal glass are probed via scanning tunneling and atomic force microscopies, scanning electron...     

Structural changes on the surface of tungsten foils under uniaxial tension

A change in the surface morphology of recrystallized tungsten foil under the effect of uniaxial tension in ultrahigh vacuum is studied by low-energy electron diffraction and atomic force microscopy. It is found by using low-energy electron diffraction that on the foil surface consisting of separate blocks with dominant face (112), there is a turn in orientation of the structural blocks. The analysis of the topograms of different areas of the side surface of a broken sample, obtained by atomic force microscopy, enabled the association of changes in the atomic structure of the surface layers of foil with a change in its relief by mechanical action.     

Characteristics of the elastic strain of a Ge(111) surface under a mechanical load

Estimates are obtained for various components of the elastic strain in a Ge(111) surface layer under isotropic lateral tension. Agreement with the reversible components of surface thinning, derived from energy shifts in the volume and surface plasma peaks, suggests that the latter have an elastic character. It is conjectured that the anomalously high strain in a thin surface layer is due to the partially quasielastic variation of the relief of strained semiconductor surfaces. Fiz. Tverd. Tela (St. Petersburg) 41, 641–644 (April 1999)     

Dynamics of the Surface Morphology of a Tungsten Foil under Load

Physics of the Solid State - The dynamics of changes in the surface morphology of recrystallized tungsten foil under the action of uniaxial tension was studied in situ by the methods of low-energy...     

Influence of low-temperature annealing on the morphology of the surface layer of an iron-based amorphous alloy

The influence of isothermal annealing on the chemical composition, microstructure, and surface relief of ribbons of an amorphous Fe₇₇NiSi₉B₁₃ alloy was studied using Auger electron spectroscopy and transmission electron, atomic-force, and scanning tunneling microscopy. It is established that an annealing below the glass transition temperature results in a boron enrichment of the ribbon surface layer on the side of the ribbon that was not in contact with the roller during quenching. On both sides of a ribbon, islands of crystallized material 2–5 μm in size appear consisting of nano-and microcrystals of α-Fe on the roller-contacting side and of iron boride on the opposite side. The surface relief on the roller-contacting side of a ribbon and that on the opposite side are shown to differ in terms of their spectral and fractal characteristics after annealing. The effect of the chemical composition and excess free volume of the surface layer on the formation of islands of crystallized material and surface relief is discussed.