Oleate-Based Protic Ionic Liquids As Lubricants for Aluminum 1100

Abstract

Because of their structures and tunable properties, viscosity among them, oleate-based protic ionic liquids (PILs) were used as lubricants for aluminum, aiming to apply them in metal forming processes. Three oleate-based PILs with three ammonium-based cations were tested as lubricants, in order to evaluate the influence of the cation structure on the tribological performance. Coefficient of friction (COF) determination and subsequent wear computations were conducted. Erichsen tests were also conducted to evaluate their performance in metal forming processes. Oleate-based PILs maintained a low COF value, with the formation of uniform tribofilms that promoted the wear reduction down to 98% compared to the dry condition. Considering wear, their performance surpassed the one of a studied commercial lubricant. In spite of this, Erichsen test revealed that the PILs yielded a performance comparable to that of the commercial lubricant. The advantages of the use of these PILs are their simple synthetic route, low cost, low toxicity, and chemical stability.

Effect of Ionicity of Three Protic Ionic Liquids as Neat Lubricants and Lubricant Additives to a Biolubricant

“…Although the study of ILs in lubrication is dominated by AILs, the study of PILs and, in particular, halogen-free PILs as novel lubricants and lubricant additives is receiving the attention of tribological researchers [33,[35][36][37][38][39][40][41]. For instance, Zhao et al [41] synthesized a series of PILs having dodecyl-ammonium cations with S-(1-carboxylpropyl)-N,N-dialkyldithiocarbamate anions, where the alkyl group was either ethyl, butyl, or octyl.…”

N‐methyl‐2‐hydroxyethylammonium oleate ionic liquid performance as corrosion inhibitor for mild steel in hydrochloric acid medium

“…[11,13,17,18] PILs are thermally and chemically stable, so they can be recycled, which can make synthetic routes less expensive, more efficient, and environmentally less hazardous. [19,20] Due to all this versatility, PILs can be used in a wide range of applications such as an inert electrolyte to verify diffusivity of protective coatings, [21] lubricants, [22][23][24] nonaqueous plating systems, [25] catalysis, [26] fuel cells, batteries, [27] storage media for toxic gases, [28] performance additives in pigments, [29] and corrosion inhibitors. [7,30] In consequence, they have gained attention from many industries.…”

“…[27,31,32] The use of PILs as corrosion inhibitors is very promising, owing to their potentiality to be tailored for this application by modifying their structure. [23,33] It is vital to understand how structure makes them function as corrosion inhibitors. Compounds containing functional groups such as amines and carboxylic acids were investigated by Yoo et al, [12] Amin et al, [34] and Amin and Ibrahim, [35] and they were reported to present promising anticorrosion effects.…”

“…In previous studies performed by our research group, Ortega Vega et al [23] reported the use of N-methyl-2-hydroxyethylammonium oleate ([m-2HEA] [Ol]) and other similar ILs as lubricants for aluminum. Furthermore, Schmitzhaus et al [36] reported in an early study that [m-2HEA][Ol] worked as mixedtype corrosion inhibitor, with predominance in anodic processes, for steel in a neutral chlorinated solution.…”

“…The density is in the range of 0.93-0.96 g/cm 3 . [23,37] For all the experiments, a freshly prepared 0.1-mol/L hydrochloric acid (Synth® 37%) solution was used. Concentrations of [m-2HEA][Ol] ranging from 0.5 to 2.5 mmol/L were tested.…”