Model of non-interacted «concentration waves». In simple case the tribologic system from two compositional materials (CM1 and CM2) may be presented by following scheme CM1/°/CM2, where the symbol ° is denotes the «third body» without liquid lubricant. The composition of «third body» is the rezult of the «concentration waves» addition from CM1 and CM2. Then the friction coefficient and the sum velocity of linear wear are the following:

where and are the tribologic properties of the CM1 and CM2 in the CM1/°/CM1 and CM2/°/CM2 systems, accordingly. The CM1 tribologic properties are may be calculated by next formulae:

If the relative synergic effect for each CM is the next relation:

(by α = αi and k_{i }≅ 0,5; kn,i ≅ 0),

the common synergic effect may be determined by following form: <d> = 2 <α2> (1– <α>), where: is the average concentration of the CM1ÇCM2 solid components into the «third body» volume. It’s note, this additive model of non-interacted «concentration waves» are may be used for prediction of CM tribologic properties in some systems [1–5].

Model of interacted «concentration waves». The tribologic properties of the compositional materials (CM) CMi (i = 1,2) in CMi/°/CMi systems are may be calculated by next relations:

where and ) are the sets of average properties values of the solid (with concentration αi) and lubricant CMi components according to «standard scale», the symbol ° is denotes the «third body» without liquid lubricant, δi – are the relative synergic effect for each system.

Let’s assume that the interacted «concentration waves» from each CMi are determine the composition of the «third body». Then the additive model of the friction coefficient and the sum velocity of linear wear calculation may be presented by next formulae:

f = flub + (<α> – <d>)(fsol – flub);

Ii = Ilub,i + (<α> + <d>)(Isol,i – Ilub,i),

where

the value – is the average concentration of the solid components into «third body» volume [6].

The relative synergic effects are may be presented by following relations:

(for the velocity of linear wear) and

<d> = 2 <α>^{2}(1– <α>) (for the friction coefficient).

It’s need to note, this additive model of interacted «concentration waves» are may be used for prediction of CM tribologic properties in sоme systems [5, 7].