Femtosecond Pulsed Ti:Sapphire Laser-Assisted Surface Texturing on Piston Ring and Its Tribology Characterization

Abstract

Femtosecond laser-assisted surface texturing of compression piston-rings is proposed and demonstrated. A femtosecond pulsed Ti3+:sapphire laser is used to generate dimples of the same size but with different area density on a moly-chrome ceramic deposited cast iron piston ring. The influence of the surface morphology and tribology operating conditions, such as reciprocating frequency and temperature of the lubricant, on friction and wear characteristics of textured piston rings and plateau honed liner samples is investigated. A decrease in the friction coefficient is observed with the texturing of rings. The dimple area density, which is defined as the ratio of the total textured area and the total area of the surface, of 16% and 27% offered a reduced coefficient of friction and minimize wear on the liner surface.

A review of advances in tribology in 2020–2021

“…However, little effect or even negative effects were also reported compared with texture-free surfaces, if the surface texture is not appropriately designed and/or fabricated in some cases. Laser surface texturing is most studied and a widely applied technology, which has been used in surface modification of piston ring [479], on stator surface in ultrasonic motors [480], on the Ti-6Al-4V biomedical materials combined with chemical assembly of a graphene oxide film [481], on a Si 3 N 4 disc sliding in water against a Si 3 N 4 ball [482], on UHMWP samples for bio-implants [483], on TC4 (Ti-6Al-4V) titanium alloy disc sliding against a UHMWP ball in simulated body fluid (SBF) [484], on a lead bronze coating surface [485], on a 42CrMo4 steel disc reciprocating under starved lubrication [486], and on the water-lubricated thrust ball bearing washer surface made of high density polyethylene (HDPE) specimens, manufactured using 3D printer technology [487]. Ding et al [488] constructed 3 types of dimpled surfaces, type A: 'wide & deep' by pico-second laser ablation, type B: 'narrow & shallow' by one-step post-polishing type A, and type C: 'wide & shallow' by two-step postpolishing of type A, on a smooth AMS5630 440C stainless steel sample for investigation the effect of surface texturing on material transfer behavior of the X1 PTFE/glass fiber woven fabric composite (bonded by phenolic resin) when sliding against the textured steel samples.…”

Effect of ceramic surface texture on the tribological property of ceramics and carbon fiber reinforced silicon carbide ceramic matrix composite (C/SiC)

“…The debris enters into the ground scratches, dimples and grooves of the interface, and a softer and weaker cutting ability between the interface cannot remove them quickly and instantly, thus resulting in a smaller COF, a more stable friction process, and smaller pin and disc wear rates. However, the laser-fabricated micro dimples and grooves introduce unwanted dross, or resolidification damage [14], along with the micro-cutting mechanism of improperly oriented grooves [17], slightly deteriorating friction performance. On the other hand, for the counterpart of Si 3 N 4 -C/SiC, the hardness mismatched, resulting in the debris fast peeling off from the texture and severely micro-cutting from the grooves.…”

“…Laser engraved texture is frequently applied in the corresponding researches due to its advantages of easy access and good adaptability to industrial production. Ezhilmaran et al [14] employed femtosecond pulse laser to engrave micro dimples (diameter was 100 μm and aspect ratio was 0.2) onto the friction surfaces to avoid unwanted burn, dross, or resolidification damage, and studied the impact of different area density of the dimples to the friction behavior. Li et al [15] applied an Nd:YAG laser system with a wavelength of 1064 nm to fabricate micro dimples of 200 μm-diameter and 10, 20, 30 μm-depth, and studied their improvement on the friction behavior under abrasive wear.…”

On the Role of Friction Modifier Additives in the Oil Control Ring and Piston Liner Contact

“…One of the main areas where frictional losses occur is in the sliding contact between the piston ring and cylinder liner. Tribological improvements to these conjunctions have been made over the years through a combination of surface coatings, texturing of the piston ring and cylinder liner [4][5][6] and improved lubricants.…”