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This paper aims to enhance lubrication performance of the pitcher plant–like textured surface with various parameters.

A pitcher plant–like structure surface is fabricated on the copper alloy, and the lubrication performance of the pitcher plant–like structure with various parameters is evaluated. In addition, the pressure distribution and oil film load capacity of the pitcher plant–like surface are simulated based on Navier–Stokes equations.

When the direction of motion aligns with the pitcher plant–like structure, the friction coefficient remains lower than that of the nontextured surface, and it exhibits a decreasing trend with the increasing of the texture width and spacing distance; the lowest friction coefficient (0.04) is achieved with B = 0.3 mm, L = 1.0 mm and θ = 45°, marking a 75% reduction compared to the nontextured surface. Simulation results demonstrate that with the increase in texture width and spacing distance, the oil film load-bearing capacity demonstrates an increasing trend.

Bionic pitcher plants are prepared on the copper alloy to improve the lubrication performance and wear resistance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0119/

The accuracy of the machining process is significantly impacted by the performance of hydrostatic bearings. This paper aims to analyze the influence of micro-textured on the performance of the hydrostatic bearing, and the performance of the bearing is improved by designing the arrangement of micro-textured.

Different designs have been used while creating micro-textured bearings. The finite element models of bearing with smooth and micro-textured were established and solved using the computational fluid dynamics method. The arrangement scheme of the micro-textured was evaluated by comparing the influence of the distribution position and arrangement of the micro-textured on the bearing performance.

To improve the performance of the bearing, the bearing capacity was significantly increased, and the friction coefficient of the bearing was decreased when the micro-textured was distributed in the form of an obtuse angle arrangement in the maximum pressure area of the bearing. The experimental findings validate the analysis method.

In this paper, the effect of irregularly arranged micro-textured on bearing performance is investigated to improve the bearing capacity and lubrication status.

The purpose of this paper is to investigate a partially textured slider of infinite width with orientation ellipse dimples in liquid application.

In this paper, the pressure distribution of lubrication between a partially textured slider and a smooth sliding slider is calculated by the multi-grid method. For the same dimple area, the influence of the ellipse dimple with geometric parameters, and distribution and orientation on the hydrodynamic lubrication is evaluated in terms of the dimensionless average pressure for a given set of operating parameters.

In the present work, the magnitude of the dimensionless average pressure seems proportional to the slender ratio. Consequently, the slender ratio may be chosen as large as possible based on fabrication techniques. The longer axes of ellipse dimples placed parallel to the direction of sliding always show the better hydrodynamic effect. Furthermore, the results show that the ellipse dimples can greatly improve hydrodynamic effect of partially surface textured slider of infinite width by proper design of these texturing parameters.

This paper develops a partial surface texturing infinitely width slider with orientation ellipse dimples for improving hydrodynamic lubrication.

The purpose of this paper is to maximize the load-carrying capacity (LCC) of a rotating ring, a numerical model optimizing both the surface and bottom shape of its surface textures is proposed.

The Reynolds equation is used to evaluate the film pressure and LCC obtained by integrating the film pressure is set as the objective function. Around the center of the computational domain, radial lines with an equal angle between adjacent ones are produced and the surface contour of textures is obtained by connecting the endpoints using a spline curve. The bottom profile is then obtained by connecting the endpoints of two vertical lines at the circumferential ends of textures. Lengths of these lines are set as design variables and genetic algorithm is used to solve optimization models.

Results show that optimum textures have an “apple-like” surface contour and a “wedge-like” bottom profile, which are both expressed by smooth spline curves. Optimum wedge-bottom textures generate higher LCC than optimum flat-bottom textures. Moreover, the optimum textures have the highest LCC compared with optimum grooves proposed previously, which validates the practical value of the current optimization model.

This work presents a comprehensive optimization method of texture geometry, which provides a new idea of the design of surface textures.

The purpose of this paper is to study the pumping efficiency of oil seals with different surface textures at different speeds, and the influence of the rotation direction of triangular texture on the sealing performance was further analyzed.

Based on the theory of elastohydrodynamic lubrication and the pumping mechanism of rotary shaft seals, establishing a numerical model of mixed lubrication in oil seal sealing area. The model is coupled with the lip surface texture parameters and the two-dimensional average Reynolds equation considering the surface roughness.

The results show that the application of lip surface texture technology has obvious influence on the oil film thickness, friction torque and pumping rate of oil seal. The triangular texture has the most significant effect on the increase of pump suction rate. When the rotation direction of triangular texture is 315 degrees, the pumping rate of oil seal is the largest compared with the other seven directions.

The model has a comprehensive theoretical guidance for the design of new oil seal products, which provides a certain basis for the application of surface texture technology in the field of sealing in the future.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2020-0198/

The purpose of this study is to reveal the tribological performance of the textured rolling bearing.

In the present study, the oil film pressure distribution and load capacity analysis method are established, which integrate the micro-texture model and Hydrodynamic lubrication (HL) methods. The tribological performances of the textured rolling bearing under the various working condition, texture dimension and texture type are investigated systematically.

The results show that the oil film load capacity increases with the increase in the texture size. As the texture depth increases, the oil film load capacity increases first and then decreases, and then the load capacity is the largest at the texture depth range of 3 to 5 µm. In addition, the oil film load capacity of the matching pairs, such as Si4N3-Si4N3, GCr15- Si4N3 and GCr15-GCr15 are compared; the results show that the cases of using ceramic material can improve oil film load capacity of textured rolling bearing.

The current manuscript can be useful for supporting the reliability and life research of textured rolling bearing.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2020-0055

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/

In the present work, the effect of water on some physical properties of false-twist textured polyamide 6 yarn was studied. A laboratory false-twist texturing machine was modified by a water bath in order to wet the feed yarn before entering the texturing zone. Polyamide 6 yarn was textured at the texturing speeds of 51, 85 and 119 m/min and twist levels of 2165, 2559 and 2954 turns per meter, with and without water bath. The properties of textured yarn in the aspects of crimp characteristic and tensile behavior were determined. The properties of wet textured yarn were also compared with normal (dry) textured yarn. The results show that the tensile and crimp property values of wet textured yarn are lower than those of normal (dry) textured yarn. Wetting of feed yarn changes the stability of twisting–untwisting process in false-twist texturing, and it seems that some fraction of twist is maintained in the final textured yarn. This residual twist results in non-bulky appearance of wet textured yarn.

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.

The purpose of this study is to investigate the influence mechanism of different interface component surface textures on the ultrasonic motor (USM) output performance.

The energy transmission mechanism of the traveling-wave ultrasonic motor 60 (TRUM-60) was numerically and experimentally investigated by fabricating dimple textures with different feature types on the friction material and the stator.

Textured friction material can increase the contact range effectively, and thus, can improve the friction characteristics of the interface and the output performance of the TRUM-60. The experimental results verified the expected influence mechanism and demonstrated that the use of either a textured friction material or stator has a very different effect on USM output performance. A textured PI-based friction material improved the TRUM-60 output performance, resulting in a maximum energy conversion efficiency of 57.11%. However, a textured stator degraded the TRUM-60 output performance, resulting in a minimum energy conversion efficiency of only 44.92%.

The results of this study provide a theoretical foundation for improved USM designs with textured interfaces.