Four-ball tests using 12.7 mm diameter steel bearing balls were conducted to evaluate the load-carrying and extreme pressure properties of admixtures of paraffin oil with 1, 5-diaryl-2, 4-dithiomalonamides and a sulphur-phosphorus commercial additive (0.5 per cent wt/vol.). 1, 5-Di-p-methoxyphenyl-2, 4-dithiomalonamide exhibiting wear scar diameter and friction coefficient values of 0.58 mm and 0.058 at 100 kgf (ISL) and 2.18 mm and 0.077 at 500 kgf as compared to the values of 2.05 mm and 0.022 at 56 kgf (ISL) and 2.73 mm and 0.43 at 100 kgf for paraffin oil appeared to be most effective. The surface topography of the wear scars were examined by scanning electron microscope.
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References
1.
DaveyW.EdwardsE.The extreme pressure lubrication properties of some sulfides and disulfides, in mineral oil, as assessed by four-ball machine. Wear, 1957/58, 1, 291.
2.
GodfreyD.Friction of grease components during boundary lubrication. ASLE Trans., 1964, 7(1), 24.
3.
AllmK. G.FordJ. F.The influence of chemical structure of the load carrying properties of certain organo-sulphur compounds. J. Inst. Petrol., 1965, 51, 145.
4.
AllumK. G.ForbesE. S.The load-carrying mechanism of organic sulphur compounds—application of electron probe microanalysis. ASLE Trans., 1968, 11, 162.
5.
Odi-OweiS.RoylanceB. J.XieL. Z.The experimental study of initial scuffing and recovery in sliding wear using a four-ball machine. Wear, 1987, 117, 267.
6.
MammeaA.AgarwalC. V.VermaV. K.The load-carrying properties of certain S-alkylisothioamides and their effectiveness as extreme pressure lubricant additives. Wear, 1981, 71, 355.
7.
MammenA.VermaV. K.AgarwalC. V.The EP performance of certain S-benzyliso-formidinothiocarbamides in the four-ball test. Tribology Int., 1984, 17(5), 289.
8.
MammenA.AgarwalC. V.VermaV. K.Wear reduction using some extreme pressure lubricant additives and their tri-bological studies. Lubric. Sci., 1988, 1, 81.
9.
BarnikowG.KathV.RichterD.N, N'-Diaryl-substituted dithiomalonamides. J. Prakt. Chem., 1965, 30(1–2), 63 (in German); Chem. Abstr., 1966, 64, 3411c.
SinghT.SinghR.VermaV. K.NakayamaK.A study of N, O and S heterocyclic compounds as potential extreme pressure lubricant additives. Tribology Int., 1990, 23(1), 41.
