MM Science Journal, December 2012

INCREASE OF THE EFFICIENCY OF THE PRODUCTION LINES FOR THE SPINNING OF INORGANIC NANOFIBERS BY THE ELECTROSTATIC FIELD INTENSITY OPTIMIZATION

Michal Petru, Ondrej Novak, Petr Lepsik
Keywords: electrostatic field | intensity | potential | nanofibers | FEM | relative permittivity

Increase of the intensity of the electrostatic field may be carried out in different ways, for example by increasing the charge or changing the environment conductivity. Higher overall intensity does not necessarily lead to an increase of productivity of nanofibers, because it is influenced also by the distribution of the intensity of the electrostatic field. Optimization efforts for a productivity (…)

MAPPING OF LUBRICATING FILM THICKNESS IN HUMAN HIP JOINT REPLACEMENTS

Dalibor Bosak, Jan Lastuvka, Martin Vrbka, Tomas Navrat, Martin Hartl, Ivan Krupka
Keywords: Biotribology | Bovine serum | Film thickness | Artificial hip joint | Colorimetric interferometry

This paper describes experimental mapping of lubricating film thickness and mechanism of its forming in contact of CoCrMo femoral head with a diameter of 28 mm and a glass disc with presence of bovine serum as a substitute of synovial fluid occurred in a natural joint. The contact area was illuminated by a xenon lamp and recorded by a high-speed camera. The load applied to the contact area was 5 N (…)

FRICTION OF NON-CONFORMAL CONTACTS UNDER STARVED EHD LUBRICATION

Fadi Ali, Martin Hartl
Keywords: Friction | Starved lubrication | Non-conformal surfaces | EHD lubrication

This paper presents experimental results of measuring the friction coefficient of smooth non-conformal surfaces (ball-on-disk test) in the range of elastohydrodynamic lubrication. The coefficient of friction under starved lubrication was observed under relative sliding motion by using a Tribometer and torque sensor. On the other hand, interferometric images were captured by a digital camera simulta (…)

COMPUTATIONAL SIMULATION OF GALVANIC CORROSION UNDER THE THIN FILM OF ELECTROLYTE

Vit Jenicek, Martina Pazderova, Linda Diblikova
Keywords: galvanic corrosion | thin film electrolyte | model | Simulation | analysis

Current working practice for the risk analysis of the damage by galvanic corrosion relies on tabulated values of open circuit potentials, the calculation of surface areas of the metals and is largely based on the experience. In this paper a computational simulation of corrosion attack of the constructions that are exposed to the thin film of electrolyte is presented. Theoretical basis of used math (…)