Anisotropy of the tribological performance of periodically oxidated laser-induced periodic surface structures

Laser-induced periodic surface structures (LIPSS) enable advanced surface functionalization with broad applications in various fields such as micro- and nanoelectronics, medicine, microbiology, tribology, anti-icing systems, and more. This study demonstrates the possibility of achieving anisotropy in the tribological behavior of C45-grade steel structured by nanosecond laser radiation using the LIPSS method. The lateral surface of the steel roller was irradiated with a pulsed Nd:YAG laser at an optimum intensity I = 870 MW/cm2 for the formation of LIPSS. Two sets of samples were formed with LIPSS that were perpendicular and parallel to the roller’s rotational motion direction. The Raman intensity maps revealed that the LIPSS structure consisted of periodically arranged oxides at the top of hills. At the same time, the valleys of the LIPSS structures were almost not oxidized. These results correlated well with scanning electron microscopy energy dispersive X-ray spectroscopy mapping and atomic force microscopy measurements. A comparison of Raman and X-ray photoelectron spectroscopy spectra revealed that both the magnetite phase and traces of the hematite phase were present on the surface of the samples. Tribological tests were performed in two cycles with periodic changes in the normal clamping force and sliding speed. It was found that the LIPSS structures which were formed perpendicularly to the sliding direction on the roller had a significantly greater impact on the friction processes. Structures oriented perpendicular to the direction of motion had a positive influence on reducing the energy consumption of a friction process as well as increasing the wear resistance compared to LIPSS formed parallel to the direction of motion or ones having a non-texturized surface. Laser texturing to produce LIPSS perpendicular to the direction of motion could be recommended for friction pairs operating under low-load conditions.European Regional Development FundBaltic-German University Liaison OfficeGerman Academic Exchange Service (DAAD

Studijos užsienyje pagal Europos Sąjungos SOCRATES/ERASMUS programą

Vytauto Didžiojo universitetasŽemės ūkio akademij

LŽŪU tarptautinės programos

Vytauto Didžiojo universitetasŽemės ūkio akademij

Tribology Science in Lithuania and Worldwide: New Trends

Vytauto Didžiojo universitetasŽemės ūkio akademij

Calculation methodology of dry sliding bearing of metal-polymeric reverse friction pair

Calculations methodology is created for the comparative maximum load in the dry friction sliding bearing of metal-polymeric friction pair. If the load value exceeds the allowable load, then the construction of the sliding bearing with the reverse slide pair is considered to be reliable. The experimental data of friction coefficient for comparable calculations were gain by the original testing-bench for sliding friction pairs. The verifying thermal calculation of the sliding bearing allows to determine the maximum temperature and loading force of the sliding bearing. This temperature predetermines the fitness for using this polymer type and selection of the type of polymeric material for coating of the shaftVytauto Didžiojo universitetasŽemės ūkio akademij

Mašinų tribologinio patikimumo valdymo modeliavimas

Santr. anglBibliogr.: p. 309 (5 pavad.)Vytauto Didžiojo universitetasŽemės ūkio akademij

The Provision of Lithuanian Farmers with Agricultural Machinery and Perspectives of Inter-Farm Technical Assistance

Vytauto Didžiojo universitetasŽemės ūkio akademij

ECTS ; European credit transfer system :

Vytauto Didžiojo universitetasŽemės ūkio akademij

Tribologų tarptautiniai ryšiai

Vytauto Didžiojo universitetasŽemės ūkio akademij

Investigation of hydrodynamic parameters of sliding bearing with inverse friction pair

2-s2.0-84905860821 - ScopusInvestigation of some hydrodynamic parameters of metal/polymer (Phenilone F-S2) inverse friction pair (IFP) is performed: shaft location co-ordinates, thinnest oil layer, polymeric layer deformations, highest hydrodynamic pressure, friction coefficient. The received experimental values were compared to the theoretical data according to the theoretical formulas. The research results and calculations show that presented methodology could be used for calculation of shaft coordinates for lubricated metal-polymeric sliding bearing with inverse friction pair. When the main parameters of hydrodynamic wedge are the same, the inverse friction pairs can operate under hydrodynamic lubrication at 30% higher loading, comparing to base friction pair. Experimental data show that the formula for calculation of polymeric layer deformation and hydrodynamic pressure should be improved taking into account particular bearing’s length and varying of pressure along the bearing axisVytauto Didžiojo universitetasŽemės ūkio akademij