Thin films and self-organization during friction under the current collection conditions

On the Thermodynamics of Friction and Wear―A Review

“…In development of wear resistance materials, technologies that help the system to form the dissipative structures faster are very desirable (cf. Gershman and Bushe [110]). Interests in selection of materials for contacting bodies that increase the intensity of non-equilibrium processes during friction are growing.…”

Tribofilm Formation As a Result of Complex Interaction at the Tool/Chip Interface during Cutting

“…As shown in detail in [9], the change of entropy of a frictional body (dS) is: dS = dS i + dS e + dS m + dS f − dS w (1) After differentiation with respect to time, Equation (1) in a stationary condition will look like:…”

“…In the case of the tool-chip interaction, it can be either positive, due to cutting tool-chip interactions with the further formation of seizure zones or build-ups that tend to break away and eventually cause deep surface damage [23], or negative when the material transformed to the tool surface either forms lubricants (MnS for example) or interacts with the environment (tribo-oxidation), forming lubricating tribofilms [1,23]; dS f /dt-the change of entropy due to tribofilm formation as a result of the surface modification of the cutting tools with further tribo-oxidation; dS w /dt-the change of entropy due to the wear process (the "−" sign is used in the Equation 2, because the products of the wear process leave the frictional body with their own entropy). The change of entropy, dS f /dt, could be negative if non-equilibrium processes are occurring on the surface and the entropy of a frictional body is reduced (which is typical for cutting tools [24,25]), or it could be positive if there are equilibrium processes [9]. However, the sum of these terms, i.e., dS i /dt + dS f /dt > 0, is the general entropy production [18].…”

“…Various features of tribofilms (or secondary structures, i.e., generated during friction) were intensively studied [6][7][8][9][10][11][12][13][14][15][16][17]. The tribofilms generated during friction can be divided into lubricating [6] and hard ceramic tribo-phases [7].…”

Self-Organization of Friction Surface of Fe-Mn-C-B Coating With Increased Resistance to Abrasion / Samoorganizacja Powierzchni Tarcia Powłoki Fe-Mn-C-B O Zwiększonej Odporności Na Zużycie Ścierne

“…On the other hand, D.N. Garkunov considers the discovered by himself "selective transfer", also called "nonwear friction effect" to be self-organization of friction surface [12,13]. Along with A. Polyakov, he suggested the concept of dynamically created tribological protective coatings (which they called "servovite coatings" or "surfing coatings").…”