Effects of femtosecond laser texture on the tribological properties of 20CrNiMo/beryllium bronze tribo-pairs of rock bit sliding bearings under non-Newtonian lubrication

In this paper, the tribological characteristics of the unit tribo-pairs of rock bit sliding bearings under various loads and high temperatures were investigated. The conical textures, distributed in beryllium bronze surfaces with depth–diameter ratios ranging from 0.087 to 0.483, were fabricated using femtosecond laser irradiation. The friction characteristics of the 20CrNiMo/beryllium bronze tribo-pairs were tested at a high temperature of 120 ℃ and under non-Newtonian lubrication conditions using pin-on-disc configurations. The textured surfaces with depth–diameter ratios of 0.165 and 0.483 exhibited excellent lubrication and wear-resistant properties. In addition, the effects of the operating conditions on the tribological performance of the tribo-pairs were discussed.

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Tribological Studies on Oscillating Bronze Bearings Lubricated With Environmentally Adapted Lubricants (EALs)

ASME/STLE 2004 International Joint Tribology Conference, Parts A and B ◽

10.1115/trib2004-64136 ◽

2004 ◽

Author(s):

Jan Ukonsaari ◽

Elisabet Kassfeldt

Keyword(s):

Surface Layer ◽

Mineral Oil ◽

Tribological Performance ◽

Journal Bearings ◽

Operating Conditions ◽

Bearing Surface ◽

Bearing Material ◽

Sliding Bearings ◽

Synthetic Ester ◽

Tin Bronze

Different compositions of bronze materials are used for sliding bearings in various applications including those involving oscillatory motion and moderate temperatures. The compatibility of new environmentally adapted synthetic esters with different contacting surface materials is important to ensure good tribological performance. The present work deals with tribological studies on oscillatory journal bearings manufactured with three different compositions of bronze materials lubricated with EALs under boundary lubricated conditions. Under certain operating conditions, dissolution of alloying constituents from the bronze bearing material dissolute into the synthetic ester lubricant occur leading to the formation of a copper enriched bearing surface layer. Tin-bronze with synthetic ester lubricant showed more stable friction values and roughly ten times better wear results than the harder aluminium- and manganese-bronze and also outperformed the mineral oil under the same conditions.

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THE EFFECT OF THE SHAPE OF OIL POCKETS ON THE FRICTION FORCE

Tribologia ◽

10.5604/01.3001.0012.7556 ◽

2018 ◽

Vol 280 (4) ◽

pp. 151-156 ◽

Cited By ~ 1

Author(s):

Sławomir WOŚ ◽

Waldemar KOSZELA ◽

Paweł PAWLUS

Keyword(s):

Friction Force ◽

Contact Area ◽

White Light ◽

Textured Surfaces ◽

White Light Interferometer ◽

Surface Topographies ◽

Pin On Disc ◽

Starved Lubrication ◽

Lubrication Conditions ◽

Conformal Contact

Tests were carried out using a pin-on-disc tester under starved lubrication conditions. To achieve a conformal contact, a special construction was used with an adjustable counter sample. Textured surfaces with two dimple patterns (spiral an radial) and four shapes (circle, oval, triangle, and chevron) were tested. The contact area was lubricated with L-AN-46 oil. Before the tests, surface topographies of the discs were measured by a white light interferometer Talysurf CCI Lite. Tests showed that, in starved lubrication conditions, oil pocket shape and pattern affected the friction force.

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Fabricating fluorosilane self-assembled molecular film on Babbitt alloy and its tribological performance

Industrial Lubrication and Tribology ◽

10.1108/ilt-08-2021-0322 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Liguo Qin ◽

Hao Yang ◽

Yuquan Ni ◽

Guangneng Dong

Keyword(s):

Contact Angle ◽

Wear Resistance ◽

Tribological Performance ◽

Sliding Bearings ◽

Content Type ◽

Low Surface Energy ◽

Modified Surface ◽

Lubrication Conditions ◽

Bare Surface ◽

Babbitt Alloy

Purpose This study aims to improve the tribological performance of Babbitt alloy under oil lubricant condition. Thus, the surface was treated into oleophobic state by modifying with low surface energy fluorosilane (1H,1H,2H,2H-perfluorodecyltriethoxysilane). It is believed that the oleophobic surface offered excellent wear resistance of Babbitt-based tribo-pairs. Design/methodology/approach By modifying the Babbitt alloy with low surface energy fluorosilane and measuring the oil contact angle, the wetting behavior was evaluated. Using Pin on Disk tribometer, the tribological properties of bare Babbitt and modified Babbitt were quantified. The samples after the friction test were characterized by scanning electron microscope (SEM) and the anti-wear performance was evaluated under dry and oil lubrication conditions. Findings Results showed that oil contact angle of modified Babbitt was109° which was tripled compared to that of prime surface, which indicates the oleophobic behavior was greatly improved. Under dry conditions, the friction coefficient of the modified surface with different load conditions is slightly lower than that of the bare surface, while the friction coefficient of the modified surface under lubrication conditions is significantly decreased compared to that of the bare surface. Interestingly, under low load and high load, the wear rate of the modified Babbitt alloy surface is only 1/4 and 1/3 of that of the bare surface, respectively. Originality/value The work proposed an effective method to improve the Babbitt tribological performances and will lighten future ideas for the Babbitt alloy bearing with high wear resistance, which is beneficial to improve the service life of sliding bearings and has huge promotion and application value in the manufacture of sliding bearings.

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Tribological behavior of femtosecond laser textured surfaces of 20CrNiMo/beryllium bronze tribo-pairs

Industrial Lubrication and Tribology ◽

10.1108/ilt-03-2015-0042 ◽

2015 ◽

Vol 67 (6) ◽

pp. 630-638 ◽

Cited By ~ 16

Author(s):

Xia He ◽

Lin Zhong ◽

Guorong Wang ◽

Yang Liao ◽

Qingyou Liu

Keyword(s):

High Temperature ◽

Femtosecond Laser ◽

Surface Texture ◽

Femtosecond Laser Ablation ◽

Heavy Load ◽

Sliding Bearing ◽

Content Type ◽

Beryllium Bronze ◽

Working Performance ◽

Rock Bit

Purpose – This paper aims to carry out tribological experiments to explore the applications of femtosecond laser surface texturing technology on rock bit sliding bearing to enhance the lifetime and working performance of rock bit sliding bearing under high temperature and heavy load conditions. Design/methodology/approach – Surface textures on beryllium bronze specimen were fabricated by femtosecond laser ablation (800 nm wavelength, 40 fs pulse duration, 1 kHz pulse repetition frequency), and then the tribological behaviors of pin-on-disc configuration of rock bit bearing were performed with 20CrNiMo/beryllium bronze tribo-pairs under non-Newtonian lubrication of rock bit grease. Findings – The results showed that the surface texture on beryllium bronze specimens with specific geometrical features can be achieved by optimizing femtosecond laser processing via adjusting laser peak power and exposure time; more than 52 per cent of friction reduction was obtained from surface texture with a depth-to-diameter ratio of 0.165 and area ratio of 5 per cent at a shear rate of 1301 s−1 under the heavy load of 20 MPa and high temperature of 120°C, and the lubrication regime of rock bit bearing unit tribo-pairs was improved from boundary to mixed lubrication, which indicated that femtosecond laser ablation technique showed great potential in promoting service life and working performance of rock bit bearing. Originality/value – Femtosecond laser-irradiated surface texture has the potential possibility for application in rock bit sliding bearing to improve the lubrication performance. Because proper micro dimples showed good lubrication and wear resistance performance for unit tribo-pairs of rock bit sliding bearing under high temperature, heavy load and non-Newtonian lubrication conditions, which is very important to improve the efficiency of breaking rock and accelerate the development of deep-water oil and gas resources.

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Tribological Behavior of Oil-Lubricated Laser Textured Surfaces in Conformal Flat and Point Contacts

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-64309 ◽

2005 ◽

Author(s):

Andriy Kovalchenko ◽

Oyelayo Ajayi ◽

Ali Erdemir ◽

George Fenske ◽

Izhak Etsion

Keyword(s):

Wear Behavior ◽

Hydrodynamic Lubrication ◽

Surface Texturing ◽

Operating Conditions ◽

Laser Surface Texturing ◽

Stribeck Curve ◽

Textured Surfaces ◽

Lubrication Regimes ◽

Pin On Disc ◽

Conformal Contact

The effects of laser surface texturing (LST), which involves the creation of an array of microdimples on the surface with laser, on friction and wear behavior of oil-lubricated steel surfaces were evaluated. Tests were conducted in unidirectional sliding in both the conformal and non-conformal contact configurations with a pin-on-disc test rig using fully formulated synthetic oil lubricant. In conformal contact, LST expanded the operating conditions for mixed and hydrodynamic lubrication regimes to higher loads and slower speeds i.e. the Stribeck curve was shifted to the left. LST was also observed to reduce the magnitude of friction coefficients in the boundary regime. For the non-conformal contact configuration, LST produced more wear on the rubbing counterface compared to untreated surfaces. This also accelerated the run-in process in the tests with LST treated surfaces.

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Tribological Studies on Oscillating Bronze Bearings Lubricated With Environmentally Adapted Lubricants (EALs)

Journal of Tribology ◽

10.1115/1.2000267 ◽

2004 ◽

Vol 128 (1) ◽

pp. 181-187 ◽

Cited By ~ 3

Author(s):

Jan Ukonsaari ◽

Elisabet Kassfeldt

Keyword(s):

Surface Layer ◽

Mineral Oil ◽

Tribological Performance ◽

Journal Bearings ◽

Operating Conditions ◽

Bearing Surface ◽

Bearing Material ◽

Sliding Bearings ◽

Synthetic Ester ◽

Tin Bronze

Different compositions of bronze materials are used for sliding bearings in various applications including those involving oscillatory motion and moderate temperatures. The compatibility of new environmentally adapted synthetic esters with different contacting surface materials helps ensure good tribological performance. The present work deals with tribological studies on oscillatory journal bearings manufactured using three different compositions of bronze materials lubricated with EALs under boundary lubricated conditions. Under certain operating conditions, alloying constituents from the bronze-bearing material dissolute into the synthetic ester lubricant, thereby leading to the formation of a copper enriched bearing surface layer. Tin-bronze with synthetic ester lubricant showed more stable friction values and roughly ten times better wear results than harder aluminium- and manganese-bronze as well as outperforming the mineral oil under the same conditions.

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