摘要:

AbstractLaboratory simulation tests are an important stage in the selection of engine lubricants. Where these tests are brief and repeatable, they allow numerous studies and can provide a wide range of information. They are all the more valuable if they have a close degree of correlation with a specification test.The IIID high temperature oxidation test, the ME 1517 oxidation laboratory test and the Renault 30 diesel engine test are examples of specifications for the formulation of engine lubricants. The aim of the present study has been to find or develop a brief, repeatable laboratory test for these specifications and to establish a correlation between the test and the specification.Data obtained show satisfactory correlations between the TFOUT (Thin Film Oxygen Uptake Test) and the IIID sequence, the open oxidation laboratory test COST (24 h) and ME 1517 (192 h), and the ELF/ECL microcoking test and the Renault 30 turbo diesel test.

ISSN:0954-0075    

DOI:10.1002/ls.3010040302

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractLamellar lyotropic liquid crystals were evaluated as lubricants in a slow sliding ball‐on‐disk friction rig. The liquid crystalline structure was modified by addition of a monomer and the influence of polymerisation on lubrication properties was studied. The results showed that partial polymerisation of a monomer located close to the polar group layer in the liquid crystal, followed by addition of a small amount of long‐chain aliphatic hydrocarbon, gives low friction coefficient and enhances load‐carrying c

ISSN:0954-0075    

DOI:10.1002/ls.3010040303

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThis paper reports work on the evolution of films formed by some antiwear additives. Between having an additive solution in a fresh lubricant and the actual deposition of protective films on the rubbing surfaces there is a gap during which the normal actions of a given additive may be affected by the presence of another additive.Film thickness is one of the most important parameters affecting wear. Interference between additives can change the chemical composition and the thickness of the films formed and, consequently, can modify the antiwear properties of the original additive.

ISSN:0954-0075    

DOI:10.1002/ls.3010040304

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe interaction of zinc dithiophosphate and phenolic antioxidants with metal naphthenates, mainly with copper naphthenate, has been investigated. A complex compound is formed on the interaction of zinc dithiophosphate with copper naphthenate; this has a noticeable influence on the antioxidation effectiveness of zinc dithiophosphate. The possibility of increasing the antioxidising action of zinc dithiophosphate through its combination with a copper passivator is shown. The formation of complex compounds on the interaction of phenolic antioxidants with copper naphthenates depends on the structure of these additives.

ISSN:0954-0075    

DOI:10.1002/ls.3010040305

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractThe effect of an oxygen‐containing group on the wear behaviour of heterocyclic nitrogen‐containing compounds (HNCC) have been investigated on a four‐ball machine and a SRV tester. The preliminary results show that the substitution of the hydroxyl group and aldo‐group significantly increases the antiwear effectiveness of the parent compounds. However, the alkyloxyl group involved in some HNCC does not improve the wear performance of HNCC.In order to get a better understanding of the role of oxygen‐containing groups in wear chemistry, a pair of compounds, quinoline and 8‐hydroxyquinoline, were chosen for further study. The analytical results of worn surfaces, wear debris and deposits showed that the difference in sliding behaviour between quinoline and 8‐hydroxyquinoline can be related to chemical reaction at the rubbing surfaces involving metal, HNCC and a hydroxyl group in HNCC or oxygen dissolved in the base stock. Under the same test conditions, these compounds, which are similar in chemical structure, give quite different reaction products. Quinoline is decomposed and oxidised by oxygen dissolving in the base stock to form a carboxylate function (soap). In the case of 8‐hydroxyquinoline, partial surface products are converted to higher molecular species, probably due to the catalytic action of fresh metal surface being exposed by rubbing. The new species, with higher molecular weight, probably belong to a kind of friction polymer, function as a boundary lubricant, and dramatically increase the antiwear effectiveness of the compound. The antiwear mechanisms of oxygen‐containing derivatives of HNCC a

ISSN:0954-0075    

DOI:10.1002/ls.3010040306

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

ISSN:0954-0075    

DOI:10.1002/ls.3010040307

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

ISSN:0954-0075    

DOI:10.1002/ls.3010040301

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY