Surface texturing has emerged in the last decade as a viable option of surface engineering resulting in significant improvement in load capacity, wear resistance, friction coefficient etc. of tribological mechanical components. Various techniques can be employed for surface texturing but Laser Surface Texturing (LST) is probably the most advanced so far. LST produces a very large number of micro-dimples on the surface and each of these micro-dimples can serve either as a micro-hydrodynamic bearing in cases of full or mixed lubrication, a micro-reservoir for lubricant in cases of starved lubrication conditions, or a micro-trap for wear debris in either lubricated or dry sliding. The present paper reviews the current effort being made world wide on surface texturing in general and on laser surface texturing in particular. It presents the state of the art in LST and the potential of this technology in various lubricated applications like mechanical seals, piston rings and thrust bearings. The paper also describes some fundamental on going research around the world with LST.

State of the art in Laser Surface Texturing

Surface texturing has emerged in the last decade as a viable option of surface engineering resulting in significant improvement in load capacity, wear resistance, friction coefficient etc. of tribological mechanical components. Various techniques can be employed for surface texturing but Laser Surface Texturing (LST) is probably the most advanced so far. LST produces a very large number of micro-dimples on the surface and each of these micro- dimples can serve either as a micro-hydrodynamic bearing in cases of full or mixed lubrication, a micro-reservoir for lubricant in cases of starved lubrication conditions, or a micro-trap for wear debris in either lubricated or dry sliding. The paper reviews the current effort being made world wide on laser surface texturing in particular. It presents the state of the art in LST and the potential of this technology in various lubricated applications like mechanical seals, piston rings, thrust bearings, magnetic recording etc. The paper also describes some fundamental on-going research around the world with LST.

State of the Art in Laser Surface Texturing

https://cyberleninka.org/article/n/544115.pdf

Hydrodynamic lubrication of textured surfaces: A review of modeling techniques and key findings

Significant improvement in load capacity, wear resistance, friction coefficient etc. of tribological mechanical components can be obtained by forming regular micro-surface structure in the form of micro-dimples on their surfaces. A feasibility study was performed both theoretically and experimentally using the Laser Surface Texturing (LST) technique to produce the micro-dimples. Each micro-dimple can serve either as a micro-hydrodynamic bearing in cases of full or mixed lubrication or as a micro-reservoir for lubricant in cases of starved lubrication conditions. Theoretical models were developed, and laboratory tests were performed, to investigate the potential of LST in tribological components like mechanical seals, piston rings and thrust bearings. In the entire laboratory tests, friction was substantially reduced with LST compared to the non-textured components.

Improving Tribological Performance of Mechanical Components by Laser Surface Texturing

Hydrodynamic lubrication of textured steel surfaces under reciprocating sliding conditions

The potential use of a new technology of laser surface texturing (LST) in parallel thrust bearings is theoretically investigated. The surface texture has the form of micro-dimples with pre-selected diameter, depth, and area density. It can be applied to only a portion of the bearing area (partial LST) or the full bearing area (full LST). Optimum parameters of the dimples, and best LST mode, are found in order to obtain maximum load carrying capacity for a thrust bearing having parallel mating surfaces. A comparison is made with optimum linear and stepped sliders showing that parallel LST sliders can provide similar load carrying capacity. Scheduled for Presentation at the 58th Annual Meeting in New York City April 28–May 1, 2003

A Laser Surface Textured Parallel Thrust Bearing

Performance enhancements by laser surface texturing (LST) of parallel-thrust bearings is experimentally investigated. Test results are compared with a theoretical model and good correlation is found over the relevant operating conditions. A comparison of the performance of unidirectional and bi-directional partial-LST bearings with that of a baseline, untextured bearing is presented showing the benefits of LST in terms of increased clearance and reduced friction.

Experimental Investigation of Laser Surface Textured Parallel Thrust Bearings

The effect of contact conditions and material properties on the elasticity terminus of a spherical contact

The behavior of an elastic–plastic contact between a deformable sphere and a rigid flat under combined normal and tangential loading with full stick contact condition is investigated theoretically. Sliding inception is treated as a plastic yield failure mechanism, which allows static friction modeling under highly adhesive conditions. Several contact parameters such as: junction tangential stiffness, static friction force and static friction coefficient are extensively investigated. The phenomenon of junction growth and the evolution of the plastic zone in the contact region are briefly described. It is found that at low normal dimensionless loads the static friction coefficient decreases sharply with increasing normal load, in breach with the classical laws of friction. As the normal load further increases the static friction coefficient approaches a constant value that is about 0.3 for many material properties combinations.

Elastic–plastic spherical contact under combined normal and tangential loading in full stick

The potential use of laser surface texturing (LST) in hydrodynamic journal bearings is examined theoretically. The regular surface texture has the form of micro-dimples with preselected diameter, depth, and area density. It can be applied to only a certain portion of the bearing perimeter (partial LST) or the full bearing perimeter (full LST). The effect of such a texture on load capacity and on the attitude angle of the journal bearing is investigated in the present work. The optimum parameters of the dimples and favorable LST mode for maximum load capacity have been found.

Victor Brizmer

Papers

A Laser Surface Textured Parallel Thrust Bearing

Experimental Investigation of Laser Surface Textured Parallel Thrust Bearings

The effect of contact conditions and material properties on the elasticity terminus of a spherical contact

Elastic–plastic spherical contact under combined normal and tangential loading in full stick

A Laser Surface Textured Journal Bearing