Failure criteria in thin film lubrication with EP additives

摘要: Abstract The scuffing behaviour of sliding couples made from 12 NiCr 13 steel, lubricated with SAE 90 and 20 W30 oils without additives, was studied as a function relative speed bulk oil temperature. It found that the load decreases almost inversely speed. Calculations which take into account decrease in hardness at increasing temperature show fairly good constancy total contact (bulk + flash temperature) ( i.e. values ranging 550 ° to 650 °C for all test conditions). At low speeds (up 1 m s −1 ) well-defined increase when EP additives were used; higher this effect have vanished completely. Variations nominal pressure range 3 had no appreciable influence on load, indicating that, present case, associated transition boundary lubrication regime severe wear regime.