Abstract: Ablation, water etching and gold coating were studied on poly(ethyleneterephtalate)
(PET) exposed to DC Ar plasma for 240 s at 8.3 W power. Au layers were sputtered on pristine and
modified PET and their adhesion and topography were investigated. The roughness and changes of
topography after plasma treatment, subsequent water etching and gold coating were followed using
AFM microscopy. The thicknesses of ablated layer and water dissolved layer were determined using
gravimetry. A nanoindentor was used to perform microstratch tests of sputtered layers. Water
dissolving of thin layer after plasma treatment was confirmed by FTIR spectroscopy. We have
found that under the present experimental conditions ca 30 nm thick layer of PET is plasma ablated.
The surface topography changes dramatically and surface roughness increases. Another ca 16 nm
thick layer was removed under present laboratory conditions after 24hour water etching. Subsequent
coating with 50 nm thick gold layer increases surface roughness in all cases of surface modification.
Abstract: Polymer hydrogels have many different functions in the field of tissue engineering and
medicine. Modification of 2-hydroxy-ethyl-methacrylate (HEMA) and 2-ethyl-oxy-ethylmethacrylate
(EOEMA) by plasma treatment performed in Ar atmosphere at RT for 0-400 s was
studied using different techniques. Sample ablation was determined by gravimetry, surface
wettability and aging by goniometry, chemical structure by FTIR spectroscopy and surface
morphology by AFM microscopy. The plasma modification changes the sample surface
morphology. In vitro cultivation shows that the plasma treatment changes the proliferation of human
Abstract: The interaction of cells with polymers is important for their potential applications in medicine and
various areas of biotechnology. Their physico-chemical surface properties strongly influence the cell
morphology, adhesion and growth. Physical and chemical properties of pristine and modified
polyethylene (PE) films were studied. PE was modified by Ar plasma (0–400 s, 2.0 W) and than
grafted with amino acid (glycine). Structural and morphological changes of polymer were studied by
goniometry and Rutherford back-scattering (RBS). The interaction of these samples with vascular
smooth muscle cell (VSMC) from the rat aorta was studied. Number and morphology of the adhered
and proliferated cell on the pristine and modified PE was studied in vitro method. It was found that
wetting angle of the modified films decreased with exposure time. Experiments in vitro indicated
that the adhesion and proliferation of VSMC is increasing function of degradation time and glycine
Abstract: High-temperature constructional parts of aircraft engines and energy units are exposed to
high dynamic stress (fatigue processes and creep) and various temperatures in dioxide-corrosion
condition (hot corrosion, oxidation and erosion). The improvement of aero-engine and turbine
efficiency is possible through the increase of temperature in front of turbine. This requires the use of
heat-resistant and creep-resistant materials, especially nickel-base superalloys which resist
mentioned effects for a limited period of time. A deposition of protective layers should improve hot
corrosion resistance. This paper is focused on microstructure of protective layers created by codeposition
of Al and Si on nickel-base superalloys INCO 713 LC and INCO 738 LC after thermal
and thermal-stress exposition and on microstructure of basic materials (substrates). The contribution
also shows creep tests results for both superalloys with and without a protective layer.
Abstract: Well-characterised samples such as single crystals, bi-, tri- or multicrystals are needed for
basic studies of properties of solids. Growth of such metallic structures by means of the floatingzone
melting technique is demonstrated for iron base alloys, FeAl intermetallics and NiTi shape
Abstract: In an analogy to the 3D tool of tessellation classification – w−s diagram, a similar
graphical device is proposed for 2D tessellations. Any tessellation is represented by a point in the
Cartesian coordinate system with the axes Ep (the mean cell perimeter) and CV a (the coefficient of
cell area variation). Images of tessellations and p−CV a diagrams for selected tessellations with low
and high values of CV a are shown as examples.
Abstract: The estimation of grain size (volume) by using computer database of tessellations is
explained and demonstrated. As model material was selected an anisotropic material formed by
compression-moulded pellets of PVC. The pellets were first covered with carbon paste to highlight
borders of grains in final specimen and then moulded; their volumes were exactly known. Standard
profile and intercept counts were carried out on the planar sections of the specimen and used to
estimate the grain size by means of computer database. The obtained estimates were then compared
with the known pellet characteristics.
The estimation of grain volume and of other suitable characteristics by inspection of section planes
is necessary in opaque materials (e.g. metal alloys, crystalline polymers, ceramics), where their
values are inaccessible by direct measurements. The aim of this work is show that the standard
approaches can be improved with the help of a suitably prepared computer database.
Abstract: In the present work, the statistics of fragmentation is being studied in experiments with
thin glass plates under uniformly distributed quasi-static loads. For this purpose the original
pneumatic setup was manufactured. The glass plate is placed into a "sandwich" in order to fix the
fragmentation pattern after unloading and to photograph it by a digital camera. A photoimaging and
computer processing technique are used to assess the fragment areas and the total crack length.
Abstract: The lifetime of superalloy single crystals CMSX-4 and CM186LC subjected to tensile
mean stress with vibrations at high temperatures has been experimentally studied. Both beneficial
and detrimental effect of cyclic stress component has been observed. An increase of lifetime due to
superposition of cyclic component on the mean stress is explained by reduction of creep rate due to
vibrations. The onset of decrease of lifetime with increasing stress amplitude is observed when the
fatigue damage due to initiation and propagation of fatigue crack overbalances the beneficial
influence of high frequency cycling.
Abstract: The plasticity of a copper (Cu) nano-component is experimentally evaluated by a cantilever
specimen with multi-layered structure. The cantilever is monotonically loaded by a diamond tip and
the deflection at the free-end is precisely measured by a transmission electron microscope (TEM).
The plastic deformation of the Cu nano-component is successfully monitored through the non-linear
behavior of applied load, P, and cantilever deflection, δ. The plastic constitutive quation of the Cu
component is inversely analyzed by finite element method (FEM) assuming that the component obeys
the Ramberg-Osgood law. The parameters in the R-O law (σ0, n and α) are optimally fitted to
reproduce the experimentally evaluated P-δ relation. The resultant parameter set is derived as (σ0, n,
α) = (345 MPa, 3.2, 1.25). The Cu nano-component has a much higher yield stress and a hardening
rate compared with the ones in a bulk Cu.