Role of thermal, mechanical and oxidising treatment on structure and chemistry of carbon black and its impact on wear and friction: Part 2 – Boundary lubrication condition

In this paper, Al7075 alloy and 15 wt% VN/7075 composite were prepared by ball milling and hot-press sintering. The microstructure, hardness, and wear behavior under different working conditions (environmental condition: dry friction, sulfur-containing boundary lubrication, and oil lubrication) were studied. The results showed that the distribution of VN was dispersive and uniform in 15 wt% VN/7075 composite without obvious agglomeration. The hardness (119.5 Hv) of 15 wt% VN/7075 composite was 46.1% higher than the Al7075 alloy (81.8 Hv). Friction and wear behavior test results showed that under sulfur-containing boundary lubrication condition, according to the tribofilm layer on the worn surface of 15 wt% VN/7075 composite, the friction coefficient of 15 wt% VN/7075 composite decreased by 37.6% compared with the Al7075 alloy. The main wear mechanism of 15 wt% VN/7075 composite was delamination wear and abrasive wear under dry friction, while under sulfur-containing boundary lubrication and oil lubrication, it changed to mild abrasive wear.

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A scuffing model considering additive depletion in boundary lubrication

Industrial Lubrication and Tribology ◽

10.1108/ilt-05-2019-0183 ◽

2019 ◽

Vol 72 (3) ◽

pp. 267-272

Author(s):

Bora Lee ◽

Yonghun Yu ◽

Yong-Joo Cho

Keyword(s):

Boundary Lubrication ◽

Mass Conservation ◽

Additive Concentration ◽

Contact Conditions ◽

Sliding Bearings ◽

Content Type ◽

Proposed Model ◽

Lubrication Condition ◽

Scuffing Failure ◽

Sliding Distance

Purpose This paper aims to propose a new scuffing model caused by the depletion of additives in boundary lubrication condition. Design/methodology/approach The differential equation governing the distribution of additive content in the fluid film was used. This formula was derived from the principle of mass conservation of additives considering the consumption due to surface adsorption of wear particles. The occurrence of scuffing was determined by comparing the wear rate of the oxide layer with the oxidation rate. Findings If the additive becomes depleted while sliding, the scuffing failure occurs even at a low-temperature condition below the critical temperature. The critical sliding distance at which scuffing failure occurred was suggested. The experimental data of the existing literature and the theoretical prediction using the proposed model are shown to be in good agreement. Originality/value It is expected to be used in the design of oil supply grooves for sliding bearings operating under extreme conditions or in selecting the minimum initial additive concentration required to avoid scuffing failure under given contact conditions.

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Experimental investigation on the role of PVA in eliminating inhibition phenomenon of carbon black during the synthesis of polystyrene/carbon black composite particles

Polymer Engineering & Science ◽

10.1002/pen.23072 ◽

2012 ◽

Vol 52 (6) ◽

pp. 1309-1316 ◽

Cited By ~ 9

Author(s):

Juntao Yan ◽

Chunlei Wang ◽

Yan Gao ◽

Zaihang Zheng ◽

Zhiqiang Cheng ◽

...

Keyword(s):

Experimental Investigation ◽

Carbon Black ◽

Composite Particles

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Carbon black suppresses the osteogenesis of mesenchymal stem cells: the role of mitochondria

Particle and Fibre Toxicology ◽

10.1186/s12989-018-0253-5 ◽

2018 ◽

Vol 15 (1) ◽

Cited By ~ 19

Author(s):

Yulai Shen ◽

Lu Wu ◽

Dongdong Qin ◽

Yankai Xia ◽

Zhu Zhou ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Carbon Black

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A Mechanism of Sliding on the Nanometer-Thick Ag Layers

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-63818 ◽

2005 ◽

Author(s):

F. Honda ◽

M. Goto

Keyword(s):

Friction Coefficient ◽

Normal Load ◽

High Vacuum ◽

High Energy ◽

Thin Layers ◽

Ultra High Vacuum ◽

Wear And Friction ◽

Thickness Measurements

Tribological performance of sub-nano to nanometer-thick Ag layers deposited on Si(111) have been examined to understand the role of surface thin layers to the wear and friction characteristics. The slider was made of diamond sphere of 3 mm in radius. Sliding tests were carried out in an ultra-high vacuum environment (lower than 4 × 10−8 Pa) and analyzed in-situ by Auger electron spectroscopy (AES) for the quantitative thickness-measurements, by reflection high-energy electron diffraction (RHEED) to clarify the substrate cleanliness and crystallography of the Ag films, and by scanning probe microscopy (SPM) for the morphology of the deposited/slid film surfaces. As the results, a minimum of the friction coefficient 0.007 was observed from the film thickness range of 1.5–10 nm, and exactly no worn particles were found after 100 cycles of reciprocal sliding. Results have directly indicated that solid Ag(111) sliding planes allowed to reduce the friction coefficient very low without any detectable wear particles, and Ag nanocrystallites in Ag polycrystalline layers increase the size to 20–40 nm order, during sliding. The friction coefficient was slightly dependent to the normal load. Results were discussed on the role of the surface atoms to the friction, and a mechanism of sliding on Ag thin layers.

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