Resumen de Mechanism of tribo-chemical reactions of ionic liquids on titanium alloys

E Berriozabal, Amaya Igartua, Allan F. Pagano, José Francisco Cambra Ibáñez, I Minami

• In this paper, the tribological, the tribo-chemical reaction mechanisms and desorption properties of three ionic liquids (ILs), [Bu3MeP][ Tf2N], [Bu3MeN][ Tf2N] and [Bu3MeP][ (MeO)2PO2], in contact with titanium and under vacuum conditions are studied with the CATRI © UHV Tribometer developed by IK4-TEKNIKER [1]. The two ILs containing the bis(trifluoromethanesulfonyl)amide anion presented lower coefficient of friction compared to that having the dimethyl phosphate anion. The tribodesorption study revealed that it is required an induction period to decrease the friction coefficient. The end of this period is accelerated in the case of trifluoromethane ionic liquids by the CF3+ release. Hence, the CF3+ reacts with the titanium surface generating a titanium fluoride tribolayer that could act like a catalyst to generate the tribodesorption of ionic liquid cation fragments (CH3+, C2H5+, C3H7+, C4H9+). The XPS analysis confirmed the generation of a boundary film, comprising of sulfide and ...