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This paper aims to explore polyaniline (PANI) as a lubricant additive to improve the anti-corrosion and tribological properties of ionic liquids (ILs) for actual applications.

ILs were synthesized by dissolving lithium salts in synthetic oil and were used as a base oil to prepare ILs-based greases. PANI was used as an additive. The tribological properties were investigated in detail and the anti-corrosion ability was also assessed via salt spray test. After friction test, the worn surfaces were characterized by scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy to analyze the lubrication mechanisms.

PANI not only reduces the corrosion but also improves the friction reduction and anti-wear abilities of the ILs-based greases. The analysis indicates that the protective films generated on the worn surfaces were responsible for the preferable anti-corrosion and tribological properties.

This paper provides an effective approach to improve the anti-corrosion and tribological properties of ILs for actual applications.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0469/

The purpose of this paper is to synthesize a new kind of conductive grease which possesses a prominent conductive capacity and good tribological properties.

A two-step method was used to prepare complex lithium-based grease. Ketjen black (KB), acetylene black (AB) and carbon black (CB) were characterized by transmission electron microscope and used as lubricant additives to prepare conductive greases. Conductive capacity was evaluated by a conductivity meter, a surface volume resistivity meter and a circuit resistance meter. Tribological properties were investigated by a reciprocating friction and wear tester (MFT-R4000). The worn surfaces were analyzed by a scanning electron microscope, Raman spectroscopy, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscope.

The conductive grease prepared with KB has a prominent conductive capacity at room temperature, 100°C and 150°C. Further, this conductive grease also possesses better tribological properties than AB and KB greases. When the concentration of KB is 1.8 Wt.%, the coefficient of friction and wear width reduced by 11 and 14 per cent, respectively.

This work is a new application of nanometer KB as a lubricant additive in grease, which provides a direction for preparing conductive grease. The conductivity and tribology experiments have been carried out though the variation of experiment conductions.

The purpose of this paper is to synthesize a kind of core-shell Ag@polyaniline (Ag@PAN) as a lubricant additive to improve the friction reduction and anti-wear abilities of lithium-based complex grease.

The core-shell Ag@PAN was prepared by a simple method and was introduced into the lithium-based complex grease. The typical properties of Ag@PAN were investigated by scanning electron microscopy (SEM), Fourier transforms infrared spectrometer and thermal gravimetric analyzer. The tribological properties were evaluated under different conditions. After the tribological test, the worn surface was analyzed by SEM and X-ray photoelectron spectroscopy to probe the lubrication mechanisms.

The prepared Ag@PAN could greatly improve the friction reduction and wear resistance of the friction pair under different conditions. The preferable tribological performances were mainly attributed to the synergism of various lubrication mechanisms including “mending effect,” “rolling effect” and lubricating protective film, and so on.

This study synthesizes a new kind of core-shell Ag@PAN as a lubricant additive, and it possesses preferable friction reduction and anti-wear abilities.

This paper aims to explore the leaf-surface wax as green lubricant additive and compare the tribological properties between coastal and inland leaf-surface waxes of the same species plant.

The leaf-surface waxes were extracted from the leaves of Robinia pseudoacacia cv. Idaho and Populus nigra in coastal and inland areas, and then the compositions of the four kinds of leaf-surface waxes were characterized using a gas chromatography–mass spectrometry. The tribological properties of these leaf-surface waxes as lubricant additives in the base oil of synthetic ester (SE) were investigated by an MFT-R4000 reciprocating friction and wear tester. As well as the surface morphologies and chemical compositions of the wear scars were characterized by a scanning electron microscope and time-of-flight secondary ion mass spectrometry, respectively.

The results indicate that all the leaf-surface waxes as additives can effectively improve the friction reduction and anti-wear performances of SE for steel–aluminum friction pairs. Therein, coastal leaf-surface waxes have better tribological performances than inland leaf-surface waxes, which are attributed to that the leaf-surface waxes extracted from coastal plants can form a better protective film on the worn surface throughout the friction process.

This paper investigated a new kind of environmentally friendly lubricant additive and compared the tribological properties of the leaf-surface wax extracted from coastal and inland plants. The associated conclusions can provide a reference to explore the tribological performances of leaf-surface wax as green lubricant additive.

The purpose of this paper is to compare the electrical conductivity and tribological properties of magnetron sputtered silver (Ag), copper (Cu) and aluminum (Al) thin films under conductive grease lubrication.

Three types of silver (Ag), copper (Cu) and aluminum (Al) thin films were prepared by magnetron sputtering. Current-carrying friction tests were carried out by a ball-on-plate reciprocating friction and wear tester. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) were used to observe and analyze the worn surface and cross-section morphology of the films.

Silver and Cu films exhibited good conductivity and tribological properties, which were mainly attributed to the synergy of the protective tribofilm generated by conductive grease, current-induced thermal effect and magnetron sputtered films effect. Al film was worn through. Large pitting storing lubricate were only found in Ag film. Cu film showed a similar surface uniformity with Ag film.

This study provides a reference for the design and application of conductive grease and investigates the current-carrying friction behaviors of magnetron sputtered films as electrical contact materials. The comparison of current-carrying friction behaviors of the three films was rarely covered in previous studies.

The purpose of this study is to improve the corrosion resistance of the transmission towers by Zinc-aluminum-magnesium (Zn-Al-Mg) coatings doped with rare earths lanthanum (La) and cerium (Ce) (denoted as Zn-Al-Mg-Re) in Q345 steel.

The phase structure of Zn-Al-Mg-Re composite coatings has been determined by X-ray diffraction, whereas their surface morphology and cross-sectional microstructure as well as cross-sectional elemental composition have been analyzed by scanning electron microscopy and energy-dispersive spectrometry. Moreover, the corrosion resistance of Zn-Al-Mg-Re composite coatings has been evaluated by acetic acid accelerated salt spray test of copper strip.

Experimental results show that doping with La and Ce favors to tune the composition (along with the generation of new phase, such as LaAl₃ or Al₁₁Ce₃) and refine the microstructure of Zn-Al-Mg galvanizing coatings, thereby significantly improving the corrosion resistance of the coatings. Particularly, Zn-Al-Mg-Re with 0.15% (mass fraction) La exhibits the best corrosion resistance among the tested galvanizing coatings.

Zinc-aluminum-magnesium (Zn-Al-Mg) coatings doped with rare earths lanthanum (La) and cerium (Ce) (denoted as Zn-Al-Mg-Re) have been prepared on Q345 steel substrate by hot-dip galvanizing so as to improve the corrosion resistance of the transmission towers, and to understand the corrosion inhibition of the Zn-Al-Mg-Re coating.

The aim of the present paper is that three long-chain hydroxyethyl alkylimidazolium hexafluorophosphate ionic liquids (ILs) were synthesized and evaluated as lubricants for steel-steel contacts at room temperature and boundary lubrication conditions. Hydroxyethyl functional group and alkyl chain length effect on the physicochemical and fretting tribological behaviors of the ILs was comparatively investigated, as compared to traditional dialkylimidazolium ILs.

The fretting friction and wear tests were carried out using an Optimol SRV-IV oscillating reciprocating friction and wear tester. The worn surface was observed and analyzed by scanning electron microscope and X-ray photoelectron spectroscopy. The electrochemical corrosion behavior of copper disks in selected imidazolium-based ionic liquids was studied using a CHI660B electrochemical workstation.

This can be seen by comparing the results for the non-hydroxyl ILs and hydroxyl ILs that the latter exhibited the littler friction coefficient, the smaller wear volume, although the latter electrochemical corrosion behavior of copper disks is slightly higher than the former. The results also revealed that the ILs with a longer alkyl chain displayed larger viscosities, better anti-corrosion capacities, higher hydrophobic properties and more excellent friction-reducing and anti-wear performance than those with a shorter alkyl chain.

This work might offer new knowledge in the design and application of new ILs as lubricants; it also confirms some in-depth physicochemical questions, e.g. the function mechanism, the correlations between structure and performance. Additionally, a proposed interaction model between the ILs and the friction substrate has been given.

The aim of this paper was to inhibit the serious corrosion of conventional ionic liquids, a series of new ionic liquids (ILs) containing the triazole functionality, as the anti-corrosion groups were synthesized in this work.

It is well known that nitrogen and sulfur containing organic compounds have been traditionally used as corrosion inhibitors. Among them, triazole derivatives are most often used as corrosion inhibitors. To alleviate the corrosion of the ILs and further improve the anti-wear property, the authors prepared a series of imidazolium ILs modified with the triazole functionality in the present study.

The corrosion behavior of the ILs was evaluated with the iron disk corrosion test and their tribological properties were investigated on an Optimol SRV IV oscillating friction and wear tester at elevated temperatures. The results showed that the ILs with the triazole functionality could effectively reduce the corrosion and exhibit a smaller friction coefficient and wear volume than the unmodified counterpart. The ILs containing the triazole functionality can be used as the single component anti-corrosion base oils even at elevated temperatures.

The results showed that the ILs with the triazole functionality could effectively reduce the corrosion and exhibit a smaller friction coefficient and wear volume than the unmodified counterpart. The ILs containing the triazole functionality can be used as the single component anti-corrosion base oils even at elevated temperatures.

The purpose of this paper is to synthesize a series of cyclophosphazene derivatives with better tribological properties.

To improve the adsorptivity to substrate, a series of cyclophosphazene derivatives substituted with ionic liquids were synthesized. The lubricity characteristics of phosphazene derivatives were evaluated on an Optimol SRV IV oscillating friction and wear tester. Scanning electron microscope and X‐ray photoelectron spectroscope analyses were conducted to examine the morphology and chemical composition of the wear scars and the possible tribochemical changes involved in the friction process.

Alkoxycyclophosphazene derivatives substituted with ionic liquids synthesized in the present work show better antiwear ability and load‐carrying capacity in steel‐steel contacts. The density of ion pairs plays an important role on tribological properties.

The paper deals with only a limited compounds and steel‐steel contacts. The paper works on the subject progressively to explore more combinations for better tribological properties.

All the cyclophosphazene derivatives present better tribological performance and could be used as base oils, such as hard disk surface lubricants.

Ionic liquids are introduced to cyclophosphazene derivatives in this paper. This is a new method to improve the tribological properties of cyclophosphazene derivatives.

The purpose of this paper is to study the tribological behavior and mechanism of water‐soluble bismuth dithiophosphate as the additive of water‐based cutting fluid in aluminum alloy tapping.

Comparable investigation has been made on the lubrication performance of bismuth dithiophosphate and sodium dithiophosphate in aluminum alloy tapping. The aluminum alloy‐machined surface finish was observed on scanning electron microscope. The films on the work‐piece‐machined surface and the tap tool working surface were analyzed by X‐ray photoelectron spectroscopy.

The results indicated that the water medium containing 1 wt% the prepared water‐soluble bismuth dithiophosphate exhibited better tapping efficiency than the liquid paraffin containing 2.5 wt% chlorinated paraffin and 2.5 wt% sulfurized olefin. The bismuth sulfide component in the reaction film on the tap working surface plays a leading role in elevating the tapping efficiency and improving the machined surface finish.

The paper is restricted to the lubrication performance of bismuth dithiophosphate as the water‐based cutting fluid additive in 2024 aluminum alloy tapping.

The test method adopted is very close to the machined method applied in industry. The test results show that the bismuth dithiophosphate can obviously improve the tapping efficiency and the machined surface finish. Thus, it can be applied to the aluminum alloy cutting in automotive and aviation.

An attempt has been made to identify the chemical reaction film sourced from bismuth element and dithiophosphate group on the work‐piece‐machined surface and the tool working surface and their contribution to enhancing the tapping efficiency and improving the machining surface finish. This is helpful to the designers and the practitioners of the additives of metalworking fluid.