Surface texture is regarded as a promising solution for enhancing the tribological features of industrial materials due to its outstanding benefits, such as minimization of the contact area, enhancement of the load bearing capacity, storage of the lubricant, and management of the transition between lubrication regimes. Surface texture can be processed under either liquid or gas conditions. As compared to laser ablation in air, employing liquids or other gases as ablation media provides high accuracy and uniformity by limiting the heat-affected zone (HAZ) and other undesired defects to a large extent, as well as high crater structural features. In addition, the synergistic use of different liquid, solid, and additive lubricants with surface roughness recently demonstrated excellent performance. Therefore, surface texture helps to improve the tribological characteristics of a material. This paper reviews the design methodologies and applications of surface texture, emphasizing the proper selection of the appropriate laser parameters and ambient conditions for the best texture quality and functionality. Recent texture geometric design features to improve the film thickness and the self-lubricating system are presented. The ablation environment is explored using various media. The interaction between the lubricants’ types and surface textures is explored based on the operating conditions. Furthermore, surface texture applications using superhydrophobic surfaces, anti-drag, and vibration and noise friction are discussed. We hope that this review plays an enlightening role in follow-up research on laser surface texture.

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The hydrostatic journal bearing's recess pressure is to be determined using a novel approach. This method treats the circumferential bearing lands on both sides of recesses as infinitely long bearings, and the axial bearing lands on both sides of recesses as infinitely short bearings. The newton-Cotes integral formula is used to solve the definite integration. By this simplification, a new analytical expression of recess pressure considering the hydrodynamic effect on bearing land is obtained. The recess pressure versus eccentricity, supply oil pressure, recess wrap angle, and attitude angle solved by the new method is compared with that calculated by the finite difference method and Liang's method from two kinds of four-recess hydrostatic journal bearing compensated by capillary restrictor. The results indicate that the new process has high accuracy and its precision isn't almost affected by the parameters change. Moreover, the new method has low time consumption.

Artificial joint materials often wear out due to poor lubrication, affecting its service life. A compound texture (com-texture) was prepared, to improve the spreading of lubricant at the friction interface and reduce the friction and wear of artificial joint pairs UHMWPE and Ti6Al4V. The com-texture was divided into rough and smooth parts on the surface. The rough area was a hexagonal convex texture with a texture ratio of 66%, and it was covered with a recoagulated layer left by laser processing to absorb and transport lubricant to the friction interface. The smooth area was a convex texture with a texture ratio of 85%, which was the friction contact area. The texture morphology of the rough region was characterized by SEM and laser focusing microscope. It was found that the edge of the texture covered with recondensed mountains after laser processing and corroded micro-nano pits, which helped to prepare super-hydrophilic surfaces. Besides, the flow law of simulated body fluid (SBF) on textured surface was explored, and the motion process was recorded by high-speed camera. The results showed that the com-texture could transport SBF to the friction region smoothly and quickly. The friction test results indicated that the structure had improved tribological properties.