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.     

Structural peculiarities of carbon nanolayers prepared by deposition from a gaseous phase on Ni

Physics of the Solid State - The surface structure and the mechanical and electrical properties of graphite nanolayers (1–2 nm thick) obtained by the carbon deposition from a gaseous phase on...     

Diagnostics of living cells under an atomic force microscope using a submicron spherical probe with a calibrated radius of curvature

The relief and mechanical elasticity of living cells from lines A549 and L41 are studied. To minimize the destructive effect of the atomic force microscope on the cell and improve the measuring accuracy of the elasticity module, special probes with a single colloid amorphous SiO₂ nanogranule at their tips are employed. A procedure for preparing such probes is demonstrated.     

Atomic force microscopy of the supramolecular organization and strength properties of ultrathin polysiloxane block copolymer films

Ultrathin films of polysiloxane block copolymers and their composites with modifying additives of the C₆₀ fullerene have been studied using atomic force microscopy. It has been revealed that, independently of the concentration of the additives, the surface relief of the films has an ordered structure with a period of approximately 35 nm, which is associated with the presence of a spatial network of rigid block domains of ladder phenylsilasesquioxane in the block copolymer. The mechanical properties of the films have been determined from indentation tests of their surface layers. Reliable quantitative measurements have been performed with specially fabricated spherical indenters of the calibrated submicron radius of curvature. The obtained values of the strength parameters correlate with the data derived from standard physical and mechanical tests of thick films. It has been found that the addition of the C₆₀ fullerene at a level of 0.01% significantly improves the elasticity of the surface layers of the block copolymer.