Modeling of Surface Topography for Reduced Friction

The aim of the present research was to investigate surface topography in terms of different surface roughness parameters and to correlate surface topography change to friction of contact surfaces. For this purpose, different 100Cr6 plate samples with different surface topography were prepared. Using different grades and combinations of grinding and polishing samples with similar Ra values, but different Rku and Rsk values were obtained. To evaluate influence of roughness parameters on friction and wear, dry and lubricated pin-on-disc tests were carried out under different contact conditions. Test results indicate that high Rku and negative Rsk values lead to decrease in friction. To investigate the effect of surface texturing on surface roughness parameters, real roughness profiles were virtually altered to achieve virtually textured surfaces. Using NIST SMATS softgauge for calculation of surface roughness parameters, virtually altered roughness profiles were investigated in terms of texture size, shape and spacing, and their influence on surface roughness parameters, especially on skewness and kurtosis. Lower diameter, higher spacing and wedge-shaped dimples reflect in higher Rku and more negative Rsk parameters.

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Effect of Surface Roughness Parameters and Surface Texture for Reduced Friction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.695.572 ◽

2014 ◽

Vol 695 ◽

pp. 572-575

Author(s):

Samion Syahrullail ◽

Noorawzi Nuraliza

Keyword(s):

Surface Roughness ◽

Friction And Wear ◽

Test Results ◽

Textured Surfaces ◽

Roughness Parameters ◽

Contact Conditions ◽

Surface Roughness Parameters ◽

Roughness Analysis ◽

Pin On Disk ◽

Effect Of Surface

The aim of the present research was to investigate the possibility of contact surfaces with reduced friction using surface roughness analysis. For this purpose, various aluminum pin samples with different lubricant using different sliding speed values were prepared. To evaluate influence of roughness parameters on friction and wear, lubricated pin-on-disk tests were carried out under different speed contact conditions. Test results show that surfaces with high values surface roughness results in reduced friction. To investigate the effect of surface topography on surface roughness parameters and consequently on friction, real roughness profiles were virtually altered to achieve virtually textured surfaces.

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Planning surface texturing for reduced friction in lubricated sliding using surface roughness parameters skewness and kurtosis

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650112439809 ◽

2012 ◽

Vol 226 (8) ◽

pp. 661-667 ◽

Cited By ~ 20

Author(s):

M Sedlaček ◽

B Podgornik ◽

J Vižintin

Keyword(s):

Surface Roughness ◽

Tribological Properties ◽

Surface Texturing ◽

Roughness Parameters ◽

Contact Conditions ◽

Surface Roughness Parameters ◽

Micro Channels ◽

Contact Surfaces ◽

Skewness And Kurtosis ◽

Lubricated Sliding

The aim of this research was to confirm skewness and kurtosis parameters as two main roughness parameters which describe tribological properties of contact surfaces, especially pointing out their application in surface texturing. Based on our previous virtual texturing findings, steel samples were laser textured in a manner to achieve micro-channels with different spacing and width of the channels. Lubricated tests under different contact conditions were done to evaluate their influence on friction. It was confirmed that higher Sku and more negative Ssk can be used for planning surface texturing.

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Laser Surface Texturing and Electropolishing of CoCr and Ti6Al4V-ELI Alloys for Biomedical Applications

Materials ◽

10.3390/ma13225203 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5203

Author(s):

Jesús A. Sandoval-Robles ◽

Ciro A. Rodríguez ◽

Erika García-López

Keyword(s):

Surface Roughness ◽

Unit Length ◽

Surface Texturing ◽

Orthopedic Implants ◽

Laser Surface Texturing ◽

Material Surface ◽

Roughness Parameters ◽

X Ray ◽

Surface Roughness Parameters ◽

Materials Used

The interplay between a prosthetic and tissue represents an important factor for the fixation of orthopedic implants. Laser texturing tests and electropolishing were performed on two materials used in the fabrication of medical devices, i.e., CoCr and Ti6Al4V-ELI alloys. The material surface was textured with a diode-pumped solid state (DPSS) laser and its effect on the surface quality and material modification, under different combinations of laser power and marking speed, were investigated. Our results indicate that an increment of energy per unit length causes an incremental trend in surface roughness parameters. Additionally, phase transformation on the surface of both alloys was achieved. Chemical analysis by energy dispersive X-ray spectrometer (EDX) shows the formation of (Co(Cr,Mo)) phase and the M23C6 precipitate on the CoCr surface; while quantitative analysis of the X-ray diffractometer (XRD) results demonstrates the oxidation of the Ti alloy with the formation of Ti2O and Ti6O from the reduction of the α-Ti phase. The behaviors were both related with an increase of the energy per unit length. Control of the final surface roughness was achieved by an electropolishing post-treatment, minimizing the as-treated values. After polishing, a reduction of surface roughness parameters was obtained in a range between 3% and 44%, while no changes in chemical composition or present phases were observed.

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Research on the Surface Roughness Parameters of Micro-EDM

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.572.281 ◽

2013 ◽

Vol 572 ◽

pp. 281-286 ◽

Cited By ~ 1

Author(s):

Zhi Jie Chen ◽

Ji Hong Shen ◽

Yun Tao Dai

Keyword(s):

Surface Roughness ◽

Surface Morphology ◽

Surface Topography ◽

Evaluation Method ◽

Micro Edm ◽

Roughness Parameters ◽

Surface Roughness Parameters ◽

Evaluation Problem ◽

Lubrication Characteristics ◽

Morphology Characteristics

The surface topography errors of micro-EDM are mainly composed of surface roughness, surface waveness and so on. Research shows that the surface morphology provides a lot of useful information, which has serious influence on the friction and lubrication characteristics of the surface. However, for the micro-EDM surface topography evaluation problem, researchers have been using surface roughness parameters and evaluation method of mechanical process, which restrict the micro-EDM technology further development. On this account, the surface roughness parameters of micro-EDM have been deeply studied in this paper according to its technology characteristics and the surface morphology characteristics, therefore, the main researches and creative points are obtained, which the influence that the surface roughness of micro-EDM parts impact on their using performance is analyzed, and based on the surface morphology characteristics, some roughness evaluation parameters are given respectively according to peaks and valley, moreover, their numerical calculation are also gained.

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Surface Roughness after Milling of the Al/CFRP Stacks with a Diamond Tool

Materials ◽

10.3390/ma14226835 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6835

Author(s):

Elżbieta Doluk ◽

Anna Rudawska ◽

Józef Kuczmaszewski ◽

Izabela Miturska-Barańska

Keyword(s):

Surface Roughness ◽

Aluminium Alloy ◽

Surface Topography ◽

Feed Rate ◽

Metal Layer ◽

Composite Layer ◽

Periodic Pattern ◽

Roughness Parameters ◽

Surface Roughness Parameters ◽

Carbon Fibre Reinforced Polymer

This study presents the results of research on the surface quality of hybrid sandwich structures after milling with a diamond blade tool. It identifies the effects of feed and machining strategy on the roughness and topography of the surface. It provides an analysis of Ra and Rz surface roughness parameters as well as Sp, Sz, and Sv surface topography parameters. The processed object was a two-layer sandwich structure consisting of aluminium alloy 2024 and CFRP (carbon fibre-reinforced polymer) composite. The minimum values of the Ra and Rz surface roughness parameters were obtained on the aluminium alloy surface, whereas the maximum values were obtained on the CFRP surface. The same was true for the 3D surface roughness parameters—the lowest values of Sp, Sz, and Sv parameters were obtained on the surface of the metal layer, while the highest values were obtained on the surface of the composite layer (the maximum value of the Sp parameter was an exception). A surface topography analysis has revealed a targeted and periodic pattern of micro-irregularities for the vast majority of the samples considered. The statistical analysis shows that the surface roughness of the aluminium alloy was only affected by the feed rate. For the CFRP, the feed rate and the interaction of milling strategy and feed rate (Sfz) had a statistically significant effect. The obtained results provide a basis for designing such sandwich element processing technology, for which differences in roughness and topography parameters for the component materials are lowest.

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Effect of Heat Treatment on the Surfaces Topography Tested at the Cavitation Erosion from Steel 16MnCr5

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1111.85 ◽

2015 ◽

Vol 1111 ◽

pp. 85-90 ◽

Cited By ~ 1

Author(s):

Cristian Ghera ◽

Ion Mitelea ◽

Ilare Bordeaşu ◽

Corneliu Marius Crăciunescu

Keyword(s):

Heat Treatment ◽

Surface Roughness ◽

Surface Topography ◽

Surface Hardening ◽

Cavitation Erosion ◽

Heat Treatments ◽

Roughness Parameters ◽

Surface Roughness Parameters ◽

Duplex Treatment

This paper analyzes, by comparison, the changes appeared in surface topography, for 16MnCr5 steel tested at cavitation erosion, subjected to different type of the heat treatments. The purpose of research, aimed at establishing a correlation between resistance to cavitation erosions and the surface roughness parameters, for various types of heat treatment (annealing, carburizing, Duplex treatment of carburizing, followed by the surface hardening by induction). Cavitation tests were conducted on a vibrator device with piezoceramic crystals, which fully complies with the requirements imposed by the ASTM G32 - 2010. Roughness parameters were measured using a Mitutoyo apparatus.

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Artificial neural network tools for predicting the functional response of ultrafast laser textured/structured surfaces

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-021-08589-9 ◽

2022 ◽

Author(s):

Luca Baronti ◽

Aleksandra Michalek ◽

Marco Castellani ◽

Pavel Penchev ◽

Tian Long See ◽

...

Keyword(s):

Surface Roughness ◽

Functional Response ◽

Laser Processing ◽

Ultrafast Laser ◽

Generation Process ◽

Textured Surfaces ◽

Roughness Parameters ◽

Surface Roughness Parameters ◽

Artificial Neural ◽

Areal Surface

AbstractArtificial Neural Networks (ANNs) are well-established knowledge acquisition systems with proven capacity for learning and generalisation. Therefore, ANNs are widely applied to solve engineering problems and are often used in laser-based manufacturing applications. There are different pattern recognition and control problems where ANNs can be effectively applied, and one of them is laser structuring/texturing for surface functionalisation, e.g. in generating Laser-Induced Periodic Surface Structures (LIPSS). They are a particular type of sub-micron structures that are very sensitive to changes in laser processing conditions due to processing disturbances like varying Focal Offset Distance (FOD) and/or Beam Incident Angle (BIA) during the laser processing of 3D surfaces. As a result, the functional response of LIPSS-treated surfaces might be affected, too, and typically needs to be analysed with time-consuming experimental tests. Also, there is a lack of sufficient process monitoring and quality control tools available for LIPSS-treated surfaces that could identify processing patterns and interdependences. These tools are needed to determine whether the LIPSS generation process is in control and consequently whether the surface’s functional performance is still retained. In this research, an ANN-based approach is proposed for predicting the functional response of ultrafast laser structured/textured surfaces. It was demonstrated that the processing disturbances affecting the LIPSS treatments can be classified, and then, the surface response, namely wettability, of processed surfaces can be predicted with a very high accuracy using the developed ANN tools for pre- and post-processing of LIPSS topography data, i.e. their areal surface roughness parameters. A Generative Adversarial Network (GAN) was applied as a pre-processing tool to significantly reduce the number of required experimental data. The number of areal surface roughness parameters needed to fully characterise the functional response of a surface was minimised using a combination of feature selection methods. Based on statistical analysis and evolutionary optimisation, these methods narrowed down the initial set of 21 elements to a group of 10 and 6 elements, according to redundancy and relevance criteria, respectively. The validation of ANN tools, using the salient surface parameters, yielded accuracy close to 85% when applied for identification of processing disturbances, while the wettability was predicted within an r.m.s. error of 11 degrees, equivalent to the static water contact angle (CA) measurement uncertainty.

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Influence of surface functional parameters on friction behavior and elastic–plastic deformation of grinding surface in mixed lubrication state

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650118806375 ◽

2018 ◽

Vol 233 (6) ◽

pp. 870-883 ◽

Cited By ~ 1

Author(s):

Bin Zhao ◽

Song Zhang ◽

Jianfeng Li

Keyword(s):

Surface Roughness ◽

Surface Topography ◽

Mixed Lubrication ◽

Surface Model ◽

Roughness Parameters ◽

Solid Contact ◽

Friction Behavior ◽

Surface Roughness Parameters ◽

Simulation And Experiment ◽

Friction Performance

Mixed lubrication is a common lubrication regime in sliding contact and has received much attention in recent research. The influences of surface topography on friction performance in this lubrication state are significant owing to the coexistence of fluid–solid contact and solid–solid contact conditions. First, an accuracy surface model is built based on wavelet transform results. Then, the average Reynolds equation is revised for a grinding surface to be used in simulation. Third, four surface roughness parameters ( Sa, Sbi, S ci, and Svi) are selected to characterize surface topography. Additionally, the impacts on the solid–solid contact area, friction coefficient, and surface flattening are investigated. Finally, optimizations of surface roughness parameters directed toward energy saving and sliding stability are conducted and verified. Simulation and experiment methods are jointly applied to guarantee the accuracy of this research. The result of this study can provide theoretical support for machining contact surfaces.

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