The efficiency of cold steel rolling depends mainly on a quality of the metal-working coolant (MWC) [1–4]. Earlier we studied the influence of consistent medium- and high-temperature greases “Natol” , consistent anti-wear and metal-cladding greases , and metal-working coolants  on friction coefficient in still rolling on the laboratory rolling mill 100x100 (DSEA).
Friction conditions on a contact surface of metal and tool have an effect on energy-power parameters of metal forming processes and, in particular, rolling process. Besides, the friction defines quality of a surface of work metal and is a principal cause of deterioration of a working surface of the tool.
Growth of friction coefficient leads to growth of normal contact strains and reduces rolling accuracy especially for thin strips from considerable resilient flattening rollers. The friction has determinant influence on rolling result when the relation of arc length of contact l to an average thickness of a strip havg in the center of deformation is more than unit (l/havg > 1) [8, 9].
Principal kind of a contact friction between metal and the tool is the sliding friction. It has two main characters: the presence of the pressure forces pressing the tool and metal to each other and an inequality of rates of the tool and metal on surfaces of contact.
Value of tangential stress τ in metal forming theory is more often defined with help of Amonton’s law from physics:
τ = µ · p, (1)
where: µ is coefficient of sliding friction (dimensionless quantity);
p is normal contact strain, Pa.
Value of µ is different in various points of contact, but it is assumed average value which is accepted constant for all surface contacts.
The major factors which have an influence on µ value are: parameters of a roughness of the tool and metal before rolling, a deformable material, pressure between the tool and metal, rate of deformations (rolling), metal temperature. Lubricating properties of the technological liquids used as lubricants have a special influence on value of friction coefficient µ.
In cold ferrous metal rolling a wide spectrum of metal-working lubricants is used. But for nonferrous metals and in particular for copper and its alloys, the assortment of metal-working lubricants could be better. Their efficiencies were wished to be the better to.
At the present time it is widely used the following metal-working lubricants. Emulsol «АZMOL ОМ», Emulsol «Viol» (ТU 0258-011-23763315-2000), Concentrate VpCI-316 are used in cold copper alloy rolling. Oil Klubercut CO 6-102 is suitable for cutting and punching of nonferrous metals. Water-soluble cooling liquids “Rhenus”, for example, Rhenus FSC-IHU, metal-working coolant «Smalta-3» (ТU 0258-063-23763315-2008), Emulsol Т «PМ», lubricant-cooling agents «Universal-1 ТС» (ТU U 23.2-31023384.002-2004) and «ENTEKC-EМ» (ТU U 24.6-13450972.001-2002) are employed in rolling of ferrous and nonferrous metals.
The latter two metal-working coolants were taking as models for comparison in this study.