Sliding Friction of R6M5 Steel on Grade 45 Steel in Litol-24 Grease with Zinc and Cadmium Powder Additives

The sliding friction of R6M5 steel on grade 45 steel at a load of up to 1400 N under the lubrication conditions of Litol-24 grease modified with zinc and cadmium in an amount of 3 and 2 wt %, respectively, is investigated. The modified grease is shown to decrease the friction force by ~5 times and the coefficient of friction by 4–9 times. The dependence of the friction force on the normal force has four piecewise linear sections, in which a simple linear version of the Amonton–Coulomb law is obeyed, unlike friction in Litol-24 grease without additives, where the dependence consists of two sections. The generalized version of the Amonton–Coulomb law taking into account a change in the frictional interaction conditions is also obeyed.