摘要:

AbstractThis paper reports on the application‐relevant properties of sixteen commercially available vegetable oils tested without additives in accordance with established standards. Their performance was compared with each other and with that of mineral oil and synthetic esters. The basic characteristics of all the oils (density, viscosity, pour point, cloud point, flash point and fire point) were initially determined. A chemical analysis of the vegetable oils was carried out to determine the acid value, saponification and iodine numbers. Additionally, the oxidative stability of all the oils was tested. The tribological performance, lubrication, and wear protection of the oils were judged under abrasive as well as adhesive conditions. The comparative study of the test vegetable oils showed great differences in the properties of the oils. All the vegetable oils tested revealed weak points during testing, including rape seed and castor oils, which have established uses in industry. This study shows that certain vegetable oils, such as sesame oil and wheatgerm oil, may have potential for use in selected technical applications. The mineral oil and synthetic esters showed markedly superior performance when tested under adhesive conditions, but comparable behaviour to the other oils under abrasive condition

ISSN:0265-6582    

DOI:10.1002/jsl.3000210302

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

摘要:

AbstractCertain vegetable oils have been recognised as promising candidates for environmentally friendly lubricants. Their lubricity can be optimised using antiwear additives. However, decomposition of the additives, accompanied by auto‐oxidation of the vegetable oils, has been found to occur. In other words, the antiwear additives may degrade in vegetable oils, and give less oxidative stability. In order to understand the mechanism, oxidation testing of a vegetable oil was performed by monitoring the peroxide value (POV). It was observed that POV increases as soon as oxidation starts. The value reached 1400–1500 ppm within 50 h of reaction time. Then it decreased to an equilibrium value of 400–500 ppm within 200 h. Antioxidants to prevent peroxide generation were examined. Phenolic antioxidants and zinc dialkyldithiocar‐bamate exhibited good results with regard to preventing peroxide generation, whereas aromatic amines gave poor results. A synergistic effect that prevents the decomposition of the antiwear additives wa

ISSN:0265-6582    

DOI:10.1002/jsl.3000210303

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

摘要:

AbstractIn this study, sunflower oil at different concentrations of between 1 and 50% was added to base oil to obtain lubricating oil candidates. The lubricating oil candidates were characterised by ASTM methods, and their effects on the friction coefficient at 25 and 100°C at different speeds and loads in a statically loaded journal bearing were determined. The technological characteristics of the sunflower oil were determined according to standard methods.The study shows clear evidence that the modification of friction by sunflower oil is at least equivalent to that by mineral oil, and the lubricationg oil candidates containing sunflower oil show a reduction in the coefficient of friction

ISSN:0265-6582    

DOI:10.1002/jsl.3000210304

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

摘要:

AbstractThe effect of the chemical structure of fluorinated esters on the friction and wear behaviour of a steel‐on‐steel system was investigated. The friction and wear testing of a steel disc sliding against a counterpart ball of the same steel was carried out using an Optimal SRV oscillating friction and wear tester. The chemical features of the worn steel surfaces were analysed by means of X‐ray photoelectron spectroscopy, and the morphologies and elemental compositions of the worn steel surfaces observed and determined using scanning electron microscopy. The results indicate that a fluorinated ester with methylene groups that are not substituted by fluorine in the acid structure gives the best friction‐reducing behaviour and a keto‐ester shows the best antiwear p

ISSN:0265-6582    

DOI:10.1002/jsl.3000210305

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

摘要:

AbstractThe tribological properties of two novel heterocyclic derivatives as additives in rape seed oil and in mineral oil were investigated using a four‐ball machine. The morphologies and chemical features of the worn steel surfaces were observed and examined by means of X‐ray photoelectron spectroscopy and scanning electron microscopy. Both heterocyclic compounds improved the load‐carrying and extreme‐pressure capacities and the friction‐reducing and antiwear properties of rape seed oil more than they improved those of the mineral oil. Surface analyses of the rubbed surfaces revealed the formation of a protective film containing FeSO4, organosulphur compound, FeS2, polymerised ester, and organonitrogen compound when the surfaces were lubricated by rape seed oil containing the additives. The protective film formed during sliding processes contributed to the increase in the wear r

ISSN:0265-6582    

DOI:10.1002/jsl.3000210306

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

ISSN:0265-6582    

DOI:10.1002/jsl.3000210307

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

ISSN:0265-6582    

DOI:10.1002/jsl.3000210308

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

ISSN:0265-6582    

DOI:10.1002/jsl.3000210309

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY

ISSN:0265-6582    

DOI:10.1002/jsl.3000210301

出版商:John Wiley&Sons, Ltd    

年代:2004

数据来源: WILEY