https://cyberleninka.org/article/n/544115.pdf

Hydrodynamic lubrication of textured surfaces: A review of modeling techniques and key findings

Recent trends in surface metrology

Correlation between standard roughness parameters skewness and kurtosis and tribological behaviour of contact surfaces

Surface texturing is a surface modification approach, resulting in an improvement in tribological performance such as friction and wear resistance. Surface texturing can be performed either as a protruded or recessed asperity, with the latter being more popular due to advantages in terms of micro-lubrication and ease of manufacturing. There are a number of ways of material preparation for surface texturing, with the laser surface texturing being the most popular because of its flexibility and high accuracy. The performance of textured surface depends on the geometrical characteristics of the surface texture and the operating condition of the bearing components. In hydrodynamic and mixed lubrication, microcavity in negative surface texture acts as a reservoir for fluid lubricant, while in boundary lubrication, it traps wear particles to reduce further abrasion. In the past, tremendous amount of research effort has been put into the study of surface texturing, with an aim to investigate the underlying effect of surface texturing on tribological performance. This paper presents a critical review of research and development on surface texturing over the past decades, highlighting design, optimization and fabrication of surface texture, and their effects on tribological performance in terms of friction and load bearing capacity under different lubrication regimes. Numerical modelling approaches involving Reynolds and Navier–Stokes equations employed to understand and determine the tribological behaviour are discussed and compared with respect to experimental investigations. Thin film coatings on textured surface have been found to be a promising means to further reduce friction and increase wear life.

Recent development on surface texturing in enhancing tribological performance of bearing sliders

Improving tribological properties of titanium alloys by combining laser surface texturing and diamond-like carbon film

Influence of surface preparation on roughness parameters, friction and wear

Surface texturing by pulsed Nd:YAG laser

The aim of the present research work was to investigate the possibilities of designing surface texturing for different lubrication regimes and to evaluate its effectiveness, especially under starved, boundary and mixed lubrication regimes. This was achieved by combining an experimental tribological investigation with a surface-roughness analysis, a 2D FEM simulation and fluid dynamic modelling. The tribological investigation under unidirectional and reciprocating sliding was focused on the effect of the laser-texturing parameters—including the dimple depth and size, the dimple area density and the contact size—on the coefficient of friction under different lubrication regimes, achieved by varying the sliding speed, the normal load and the lubricant viscosity. The results of this investigation show that under starved lubrication conditions the textures resist sliding, resulting in increased friction, as was also indicated by the FEM simulation. Only when a very low dimple density was used could the oil-pocket effect be observed. In boundary lubrication the tribological behaviour of textured surfaces can be related to the surface-roughness parameters (R
 sk and R
 ku), with smaller dimples and lower dimple densities leading to reduced levels of friction. The largest gain in terms of friction reduction was observed when approaching full-film lubrication, where fluid dynamic modelling was used to correlate the effect of the dimple depth, size and shape on friction.

Marko Sedlaček

Papers

Influence of surface preparation on roughness parameters, friction and wear

Correlation between standard roughness parameters skewness and kurtosis and tribological behaviour of contact surfaces

Surface texturing by pulsed Nd:YAG laser

Effectiveness and design of surface texturing for different lubrication regimes

Formation of laser-induced periodic surface structures (LIPSS) on tool steel by multiple picosecond laser pulses of different polarizations