Friction induced mechanochemistry: self-adaptive lubrication through in-situ tribo-click system

[Display omitted] •An inventive in-situ tribo-click system at copper sliding asperity is proposed.•Self-adaptive lubrication is obtained via interfacial tribo-chemistry mechanism.•Friction visualization is observed by fluorescence chromogenic changes at interface.•MD give the adsorption morphology and force between products and the interface. The friction, which commonly exist on moving mechanical interfaces, accounts for structure damage and energy consumption. Traditional lubricating protection strategy mainly focus on the active additives and functional surface with high entropy as well as low friction. Here, an ingenious and groundbreaking mechanochemistry method of friction induced in-situ synthesis of lubricating and anti-wear materials is proposed in this paper. This interfacial friction modulation revolves around the configuration of a mechanical tribo-chemical reaction in combination with the classical ‘click reaction’, occurring locally on the copper sliding asperity present in the base oil. In particular, the process of friction functions as the fundamental stimulator of this tribochemical reaction, where the in-situ tribo-click product compensates for the frictional loss and instantly safeguards the tribo-interface. As an unforeseen outcome, the said resultant is found to exhibit premium friction-reducing effect under shear stress, along with a refined adaptability. It is evident that this tribo-click reaction demonstrates a distinctively efficient dynamic equilibrium process for the formation, consumption, and supply of tribo-film, which is attributable to the predominance shown by the in-situ tribo-click reaction and the self-adaptive tribological performance of the interfacial friction modulation system.