The Development of Appropriate Lubrication for SUS 304 Stainless Steel Disk against SKD 11 Tool Steel Ball (Thai)

Abstract

Physical simulation using tribometer has been carried out to determine the coefficient of friction. The influences of

lubricant viscosity, additives in lubricants and contact pressure on the fiction coefficient between a stainless steel disk and SKD ll

(JIS) cold work tool steel ball hardened to 602 HRC were explored, Lubricant viscosities of 100 cSt and 500 cSt were studied. Various

amounts of extreme pressure type additives consisting of Chlorine, Active Sulphur, Inactive Sulphur and Phosphorus were investigated,

Experiments were carried out at contact pressures of 638 MPa, 1377 MPa and 1734 MPa. The results show that low coefficients of

friction can be obtained by using high viscosity lubricants in the case of no additives or with a sufficient amount of extreme pressure

additives, consisting of Chlorine, Active Sulphur and Phosphorus at high contact pressure. Relative motion at high contact pressure

introduces a high coefficient of friction due to the break down of the lubricant film under high pressure.