Recent studies in tribology show that deterministic surface texture enhances the tribological performance of parallel sliding lubricated contacts in terms of reduction in friction and an increase in load carrying capacity. This paper presents an experimental study to assess the effect of texture size and height on hydrodynamic performance of parallel sliding thrust bearing. Positive deterministic textures of different size and height with circular, elliptical, square and triangular cross-sections are fabricated for investigation. The experiments are performed using an in-house developed thrust bearing apparatus with constant flow lubrication system. The most important finding is that all the textured surfaces produce lower frictional torque and higher bearing clearance as compared to the untextured surface under varying load and speed. From the test results, it is found that with same texture height, specimens having small texture size perform better tribological characteristics followed by medium and large size textures. Furthermore, it is reported that with same texture size, a higher value of texture height is promising better hydrodynamic performance for all shapes.

The present invention relates to characterization and the sequence of operations in photo chemical machining as a means to fabricate positive deterministic micro-textures on mild steel thrust pad surfaces. Fabrication of surface micro-texture by current technique is conceived in two-stages: where photographic emulsion process is used to pattern the microstructure, and chemical etching method is employed to fabricate the textures on mild steel surface by dissolving exposed metal surface. The texture fabricated by present invention is having slightly rough etched bottom surface with sharp edge and least amount of burrs around the texture rim and the process is also cost effective. Several aspects regarding sequence of operations in manufacturing process and the characterization of fabricated textured surfaces are discussed. The physical significance of micro-asperities on hydrodynamic lubrication is presented experimentally under constant flow system. The variation of hydrodynamic performance parameters such as frictional torque, fluid film thickness and recess pressure with different operating conditions such as varying speed and supply pressure are outlined.