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The purpose of this paper is to study a new liquid-phase assisted texture treatment method to improve the tribological properties of 304 stainless steel.

Three groups of textured type (KY, KJ and YJ) were prepared on 304 stainless steel surface using laser circular and cross scanning method in air and liquid assisted condition. The surface morphology and element content of test samples were measured with scanning electron microscope, energy spectrum. Then, the tribological test was carried out using MWF-500 reciprocating friction and wear testing machine under dry and oil lubrication condition.

The experimental results showed that the textured surface of laser processing in air was obviously blackened, and the oxygen content was increased from 16.9% to 24%. These cases did not occur on liquid-assisted laser textured surface, which induced a better wettability and surface texture processing quality. For friction test, the friction coefficient of cross-scanning textured surface prepared in assisted liquid (YJ) was the smallest. It is reduced by 55% in oil lubrication case compared to the original surface (YS). The cross-scanning textured surface prepared in air (KJ) was a little worse in friction coefficient and a little better in wear quantity than the cross-scanning textured surface prepared in assisted liquid (YJ). It is indicated that the laser processing surface with assisted liquid has obvious advantages in surface texture quality and interfacial tribological property. The main reason is that the assisted liquid plays a role in cooling and protecting action of the machined surface. The bubbles, generated at the solid–liquid interface because of the laser heat effect, scatter the laser beam and carry out the processed melt meanwhile. The lubricating medium is easier to penetrate and store in the contact interfaces because of the higher surface textured performance and wettability.

The main contribution of this work is in providing a new surface texture processing method that has a better surface micropits quality and interfacial tribology regulation ability.

Water-lubricated bearings can significantly reduce the pollution to environment because the traditional oil lubricant is replaced by water in the bearings. The ultrahigh molecular weight polyethylene (UHMWPE) has proven to be effective and reliable for the manufacturing of water-lubricated bearings. However, limited work has been done to address the improvement of the tribological performance of the UHMWPE-based water-lubricated bearings using surface texture processing. This paper aims to investigate the effects of bar-grooved surface on the tribological performance improvement of UHMWPE-based water-lubricated bearings.

For the first time, the bar grooves were processed on the surfaces of UHMWPE-based water-lubricated bearings. The CBZ-1 friction and wear tester have been used to test the wear and friction performance of the bearing samples. The LI laser interference surface contour graph and the digital microscope have been used to measure the surface morphology of the specimens. The tribological characteristics of the tested bearings were analyzed.

With bar grooves added on the surfaces of the specimens, the friction coefficient of the specimens were lower than that of the specimens without surface texture processing; the wear quantity of the two kinds of specimens were almost the same; by using the LI laser interference surface contour graph and the digital microscope to measure the surface morphology of the specimens, the furrows of the specimens with bar grooves were narrower and shallower than that of the specimens without bar grooves.

The paper implicates that the surface texture processing using bar grooves can reduce the friction coefficient and prolong the service life of the water-lubricated bearings in practical applications.

This paper fulfills an identified need to provide important theoretical and experimental support to the design of water-lubricated bearings in practical applications.

The purpose of this study is to further improve the performance of surface texture, the chemical polishing method was introduced and the effect of it on the surface morphology and tribological properties of the surface texture was investigated.

The surface texture was processed on the surface of 304 stainless steel with laser technology in air medium. Hydrochloric acid solution (pH 2.4 ± 0.05) was selected and used to soak the prepared texture samples for 12 h. The surface morphology and elemental content of the samples were measured with the white light interferometry, SEM and EDS. To obtain the effect of acid corrosion on the tribological properties of textured surfaces, the samples were tested under dry friction and oil lubrication conditions.

The detailed study shows that the melt and burr of surface texture produced with laser processing was reduced due to the corrosion effect of hydrochloric acid. Therefore, the better interfacial tribological properties was obtained due to the improvement of surface-textured morphology.

The main contribution of this work is to provide a new reference for improving surface texture quality. It also lays a foundation for improving the tribological properties of the textured interface.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2023-0094/

This paper aims to improve the wear resistance of metal rubber microfilaments and the service life. The effect of surface texture by laser processing on the fretting friction properties of metal rubber microfilaments was studied.

The LQL-F20A laser marking machine was used to fabricate a ring groove array with equal spacing and dense arrangement on the surface of metal rubber microfilaments. The test was carried out with a self-made micro-dynamic frictional tester. The topography of the microfilaments was observed by scanning electron microscopy and analyzed.

It has shown that laser surface texturing can improve the wear performance of microfilaments. Under the same experimental conditions, the microfilaments of textured surface has a smaller depth of wear than un-textured specimen. The wear resistance increases with the increase of texture density. The friction coefficient of textured specimen is significantly reduced compared with un-textured specimen, and the surface texture density of microfilaments has little influence on the friction coefficient after stabilization. In the stage of stable fretting wear, the wear depth will be more with the increase of the load.

There is little research on metal rubber microfilaments tribological properties. In this paper, the effect of laser texturing of microfilaments on micro-dynamic friction properties was studied by friction machine to provide a reference for the application of metal rubber in aerospace, medical and other fields.

This paper aims to carry out tribological experiments to explore the applications of femtosecond laser surface texturing technology on rock bit sliding bearing to enhance the lifetime and working performance of rock bit sliding bearing under high temperature and heavy load conditions.

Surface textures on beryllium bronze specimen were fabricated by femtosecond laser ablation (800 nm wavelength, 40 fs pulse duration, 1 kHz pulse repetition frequency), and then the tribological behaviors of pin-on-disc configuration of rock bit bearing were performed with 20CrNiMo/beryllium bronze tribo-pairs under non-Newtonian lubrication of rock bit grease.

The results showed that the surface texture on beryllium bronze specimens with specific geometrical features can be achieved by optimizing femtosecond laser processing via adjusting laser peak power and exposure time; more than 52 per cent of friction reduction was obtained from surface texture with a depth-to-diameter ratio of 0.165 and area ratio of 5 per cent at a shear rate of 1301 s−1 under the heavy load of 20 MPa and high temperature of 120°C, and the lubrication regime of rock bit bearing unit tribo-pairs was improved from boundary to mixed lubrication, which indicated that femtosecond laser ablation technique showed great potential in promoting service life and working performance of rock bit bearing.

Femtosecond laser-irradiated surface texture has the potential possibility for application in rock bit sliding bearing to improve the lubrication performance. Because proper micro dimples showed good lubrication and wear resistance performance for unit tribo-pairs of rock bit sliding bearing under high temperature, heavy load and non-Newtonian lubrication conditions, which is very important to improve the efficiency of breaking rock and accelerate the development of deep-water oil and gas resources.

This study aims to investigate the effects of irregular groove textures on the friction and wear performance of sliding contact surfaces. These textures possess multiple depths and asymmetrical features. To optimize the irregular groove texture structure of the sliding contact surface, an adaptive genetic algorithm was used for research and optimization purposes.

Using adaptive genetic algorithm as an optimization tool, numerical simulations were conducted on surface textures by establishing a dimensionless form of the Reynolds equation and setting appropriate boundary conditions. An adaptive genetic algorithm program in MATLAB was established. Genetic iterative methods were used to calculate the optimal texture structure. Genetic individuals were selected through fitness comparison. The depth of the groove texture is gradually adjusted through genetic crossover, mutation, and mutation operations. The optimal groove structure was ultimately obtained by comparing the bearing capacity and pressure of different generations of micro-convex bodies.

After about 100 generations of iteration, the distribution of grooved textures became relatively stable, and after about 320 generations, the depth and distribution of groove textures reached their optimal structure. At this stage, irregular texture structures can support more loads by forming oil films. Compared with regular textures, the friction coefficient of irregular textures decreased by nearly 47.01%, while the carrying capacity of lubricating oil films increased by 54.57%. The research results show that irregular texture structures have better lubrication characteristics and can effectively improve the friction performance of component surfaces.

Surface textures can enhance the friction and lubrication performance of metal surfaces, improving the mechanical performance and lifespan of components. However, surface texture processing is challenging, as it often requires multiple experimental comparisons to determine the optimal texture structure, resulting in high trial-and-error costs. By using an adaptive genetic algorithm as an optimization tool, the optimal surface groove structure can be obtained through simulation and modeling, effectively saving costs in the process.

The purpose of this paper is to describe the tribological characteristics with different area density of concave-convex micro-texture on the mold surface. It is a new technology to improve the quality of the workpiece to control the tribological properties through the application of concave-convex micro-texture on the mold surface.

Five groups of laser micro-texture with different area density (ratio of the concave-convex micro-texture area to the all-area) were processed on the surface of the mold steel, and the tribological properties were compared with the smooth surface of the reference sample.

The time of the running-in stage in different experimental groups was about 300 s. The fluctuation amplitude of concave-convex micro-texture friction coefficient is much larger than that of smooth plane specimen in the running-in stage. After the running-in stage, the friction coefficients were lower than that in the smooth condition and decreased with the increase of the concave-convex micro-texture area density. When the area density reached 25%, the friction coefficients no longer decreased significantly. In addition, the wear of concave-convex micro-texture surface is much lower than that of smooth surface and decreases with the increase of concave-convex micro-texture area density.

Domestic and foreign scholars have done a lot of research on the relationship between concave micro-texture and tribological properties. However, the object of this paper is a new concave-convex micro-texture, which is rarely studied in the field of tribology.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2020-0081/

This study aims to solve the premature failure of the rubber stator due to wear, reduce the frictional resistance moment of the screw pump to solve the problem of a model of Daqing oilfield screw pump oil recovery system shutdown after the difficult start.

For the first time, the rotor surface of a screw pump was treated with dot-matrix texture to study the effect of dot matrix texture on the tribological performance of the stator-rotor friction subsets of screw pump. Reciprocating friction tests with different texture morphologies (S-shape, double tongue) and angular parameters (0°, 45° and 90°) were conducted at 10% of the texture area and pump silicone grease.

When point texture was added to the surface of the rotor sample, the friction coefficient and wear quantity of the sample were lower than those of the surface without texture treatment, and the double tongue 0° combination showed the best tribological properties. At this time, the average coefficient of friction and wear is reduced by 22.8% and 62%, 28.6% and 64.8%.

The introduction of texture can effectively improve the tribological performance of progressive screw pumps, and this paper provides important theoretical and experimental support for the design of progressive screw pumps in practical applications.

The purpose of this paper is to study the effect of micro-nano surface texture on the corrosion resistance of a titanium alloy and investigate the correlation between corrosion resistance and hydrophobicity.

The surface of the Ti₆Al₄V alloy was modified by laser processing and anodizing to fabricate micro-pits, nanotubes and micro-nano surface textures. Afterward, the surface morphology, hydrophobicity and polarization curve of the samples were analyzed by cold field scanning electron microscopy, contact angle measurement instruments and a multi-channel electrochemical workstation.

The micro-nano surface texture can enhance the hydrophobicity of the Ti₆Al₄V surface, which may lead to better drag reduction to ease the friction of implants in vivo. Nevertheless, no correlation existed between surface hydrophobicity and corrosion resistance; the corrosion resistance of samples with nanotubes and high-density samples with micro-nano surface texture was extremely enhanced, indicating the similar corrosion resistance of the two.

The mechanism of micro-dimples on the corrosion resistance of the micro-nano surface texture was not studied.

The density of micro-pits needs to be optimized to guarantee excellent corrosion resistance in the design of the micro-nano surface texture; otherwise, it will not fulfill the requirement of surface modification.

The influence of the micro-nano surface texture on the corrosion resistance, as well as the relationship between hydrophobicity and corrosion resistance of the titanium alloy surface, were systematically investigated for the first time. These conclusions offer new knowledge.

This study aims to clarify the influence mechanism of surface texture (arrays of circular/square and concave/convex) on the frictional properties of WC-TiC/Co cemented carbide under a water-miscible cutting fluid (JAEGER SW-105, 5 per cent) environment.

Four types of textured cemented carbide surfaces (arrays of circular/square and concave/convex that have different textured densities and sizes) were fabricated using laser surface technology. Pin-on-disc tests between an AISI 304 stainless steel ball and WC-TiC/Co cemented carbide samples were carried out for a variety of normal loads (1, 3 and 5 N) under a water-miscible cutting fluid environment. The effects of textured type, density and size on the friction coefficient were obtained.

Compared to a smooth surface, some textured samples successfully resulted in a reduced friction coefficient. The friction coefficient of textured WC-TiC/Co cemented carbide samples depended greatly on the textured type, density and size. Given the increase in textured density (ranging from 10 to 30 per cent), the friction coefficient of the test samples first decreased and then increased for all normal loads (1, 3 and 5 N), and the minimum friction coefficient was obtained at the textured density of 20 per cent. The concave textured surface showed obvious advantages in friction coefficient reduction regardless of textured density, size and normal load compared with the convex textured surface. Finally, the correlation between textured diameter/length and Hertzian contact width was studied for various normal loads and texture sizes. A 2.6 ratio of textured diameter/length to Hertzian contact width is recommended under for lubricated sliding contact with the water-miscible cutting fluid.

The main contribution of this work is in providing a design reference and obtaining an essential understanding on the effect of surface texture (arrays of circular/square and concave/convex) on the friction of WC-TiC/Co cemented carbide under a water-miscible cutting fluid environment.