Wear and Chemistry of Lubricants

Neville, Anne; Morina, Ardian

doi:10.1002/9780470017029.ch5

Cited by 5 publications

(2 citation statements)

References 74 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The tribofi lm formation is additional infl uenced by the temperature [1]. Due to thermal and oxidative effects, the ZDDP decomposes in the tribological contact, initiated by migration of alkyl groups from oxygen to sulphur atoms [2]. Fujita and Spikes proved that ZDDP based fi lms can be generated even at room temperature on surfaces under relative motion [3].…”

Section: Introductionmentioning

confidence: 99%

Computational investigation of crack inducing forces on bearing surfaces regarding the tribofilm structure

Pape¹,

Petzold²,

Poll³

2019

Int. J. CMEM

View full text Add to dashboard Cite

To reduce wear in tribosystems, the formation of a protective tribofi lm is benefi cial. by applying additives to the lubricating oil or grease, an anti-wear boundary layer can be achieved. For simulating the induced stresses on the bearings surface, the formed tribofi lm should be regarded. In this study, cylindrical roller thrust bearings were investigated regarding a tribofi lm formed by oil containing zinc dialkyldithiophosphate (ZDDP) additives. Due to the test conditions, a smooth fi lm with low roughness forms on the surface. The fi lm consists of glassy Fe/Zn polyphosphates with a height of up to 150 nm and a width of approximately 1 µm. based on the roughness, the surface was modelled with regularly distributed dimples to be used for a fi nite element model for the contact between a roller and a bearing washer regarding contact stress and tangential forces due to slip. The dimples in the contact between roller and washer lead to an inhomogeneous pressure distribution near the surface. During the contact, the surface pads of the roller partly slide over the surface pads of the washer in dependence of the contact position. of particular interest is the deformation in running direction. If the asperities of the roller press against th e washers asperities, a signifi cant deformation at the dimples and in the volume underneath occurs. As expected, the strains occur in the regions with high deformation gradients. During rolling, the deformations lead to areas that are stretched and compressed. The maximum strains are located between the dimples and shift in rolling direction from pad to pad. It has to be assumed, that the formation of cracks starts between the dimples at the surface and develop along the stretched areas whereas the cracking in the compressed areas is suppressed or at least impeded. The simulative results were compared to literature proving that the values determined by simulation are in well agreement.

show abstract

Section: Introductionmentioning

confidence: 99%

Computational investigation of crack inducing forces on bearing surfaces regarding the tribofilm structure

Pape¹,

Petzold²,

Poll³

2019

Int. J. CMEM

View full text Add to dashboard Cite

show abstract

“…These simple concepts obscure the causes of many problems in sliding systems, particularly in those that vibrate. Basically, wear occurs when moving surfaces under load, or surface asperities, come into contact and results in plastic deformation which in turn results in a change in surface topography and/or removal of material (Neville and Morina, 2006).…”

Section: Introductionmentioning

confidence: 99%

Experimental study of friction and wear characteristics of titanium alloy (Ti-6Al-4V) under lubricated sliding condition

Sharma

Sehgal

2014

Industrial Lubrication and Tribology

View full text Add to dashboard Cite

Purpose – In the present study, an attempt has been made to examine friction and wear behaviour of Ti-6Al-4V alloy sliding against EN-31 steel under lubricative media of common commercial grade oil (hydrol-68). The paper aims to discuss these issues. Design/methodology/approach – Tribological properties of Ti-6Al-4V under hydrol-68 as lubricative media are measured using multi-tribo tester. Lubricating oil samples at different normal loads have also been analysed with the help of laser net fines (LNF) as per ISO 4406:1999. Experiments have been designed by two level full factorial method. Findings – Experimental results indicate that the wear rate of Ti-6Al-4V alloy decreases as sliding speed increases. But it shows typical transition characteristics as the normal load increases; till 30 N wear rate decreases then it increases from 30 to 50 N. Also for all loads and at every speed, the average wear increases as the sliding distance increases. The average coefficient of friction of the Ti-6Al-4V alloy decreases with the increase in sliding velocity and normal load. Lubricating oil analysis indicates that the maximum wear particle size (5-15 μm) was obtained at a normal load of 50 N. Originality/value – This paper shows that considerable reduction in friction and wear is achieved by using common grade oil hydrol-68 as lubricative media. Further, the analysis of lubricating oil using LNF at different normal loads indicates the co-existence of various wear phenomena such as cutting, fatigue, and sliding wear simultaneously.

show abstract

Nanoscale Evolution of Sliding Metal Surfaces During Running-in

Dienwiebel

Pöhlmann

2007

Tribol Lett

View full text Add to dashboard Cite

We studied the formation of tribologically induced nanocrystalline layers in lubricated contacts during running-in using a pin-on-disk tribometer coupled to a radionuclide high-resolution wear measurement system. The experiments were stopped after different running times and the sliding surfaces were analysed by atomic force microscopy, auger electron spectroscopy and focused ion beam analysis. Initially, at very high wear rates, zinc phosphate anti-wear films are formed in the contact regions of the surfaces, which slow down the wear process. During rubbing the formed films will submerge below the surface of the materials as result of large plastic deformations. This process affects the friction coefficient and the wear rate and is considered to be a key mechanism for the running-in.

show abstract

Wear and Chemistry of Lubricants

Cited by 5 publications

References 74 publications

Computational investigation of crack inducing forces on bearing surfaces regarding the tribofilm structure

Computational investigation of crack inducing forces on bearing surfaces regarding the tribofilm structure

Experimental study of friction and wear characteristics of titanium alloy (Ti-6Al-4V) under lubricated sliding condition

Nanoscale Evolution of Sliding Metal Surfaces During Running-in

Contact Info

Product

Resources

About