A CONTRIBUTION TO THE KNOWLEDGE OF SYNERGY IN TRIBOLOGY

The article contains information about the knowledge of synergism in tribology systems. Two examples of
analyses of synergism in tribology systems are presented in the article. In the first example, the interaction
coefficient (synergy coefficient) was used to evaluate a set of engine and gear oils composed of special
lubricating (surface-active) additives to improve the galling load – a measure of boundary layer strength,
evaluated on a 4-ball apparatus. Using the interaction coefficient, a 12-element set of oils (compositions) was
"separated" into three groups: synergism with additives (KS>1), sometimes strong, at Ks=2, neutral interaction
(KN=1), antagonism with additives (KA<1). Analysis of test results using the synergism coefficient also makes
it possible to select the optimal additive concentration in commercial oil. In the second case, a three-factor
system was analysed, in which the resultant (undesirable) characteristic was a measure of mechanicalcorrosion-
abrasive wear of metal parts. In specially designed experiments, the components of total wear
derived from the three underlying factors (mechanical, corrosion and environmental), and the interaction
between them was determined. The contribution of the sum component of the mechanical-corrosion-abrasive
interactions was found to range from 40 to 50% of the total wear (at 50%, there is a strong synergism KS=1).

