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This paper is a summary of the work done at Rock Island Arsenal on additives for greases. It covers antioxidants, antiwear and extreme pressure agents and rust preventive additives. No attempt is made to list the results of all additives tested. Instead the additives are divided into groups of related compounds and the results of typical, ones given. A general evaluation of each group as a whole is given, Classes of compounds which proved good as antioxidants were metal dithiocarbamates, amino‐phenyl ethers, phenylene‐diamines, methane derivatives and certain hindered phenols and di‐substituted amines. The temperature barrier was the major obstacle for the anti‐oxidants and only 9 of the 100 or so which were effective at 21()°F, were equally effective at 250°F. Sulfur, chlorine, and lead‐containing additives were the best for extreme pressure improvement. Those containing only phosphorous were belter for antiwear. Improvements in both properties could be obtained by mixing the additives. Improvement in either property seemed to depend, more upon the type of compound than upon the responsible element. For example, all sulfur containing compounds were not equal in extreme pressure properties. Some of the antiwear and extreme pressure additives were tested for their ability to reduce fretting corrosion. Results indicate that sulfur containing compounds reduce fretting while, compounds containing only phosphorous increased it. Results are given which indicate that molybdenum disulfide added to greases is detrimental to wear at lower loadings. It does improve the extreme pressure abilities of the grease. Us presence in a grease increases the rusting tendencies of greases unless an antirust agent is also present.

This paper aims to investigate the wear mechanisms, formations and effectiveness of tribofilms of new developed, antiwear additive which is called mercapthocarboxylate. The mercapthocarboxylate is a sulphur-based and non-phosphorus additive.

The effectiveness of the additive was examined through a set of laboratory endurance tests that applied with single cylinder spark ignition engine. Two types of lubricants were used to compare the engine tests which were thiophosphate (ZDDP) containing engine lubricant (phosphorus containing) and mercapthocarboxylate containing non-phosphorus and non-ash crankcase oil. Lubricants were tested under identical operating conditions for 100 hrs. The surfaces of cylinder liner and piston rings were inspected through optical microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy techniques.

Catalysis-friendly and sulphur-based mercapthocarboxylate additive can be an alternative antiwear additive package for lubrication oil due to better wear performance when compared to ZDDP.

Sulphur-based mercapthocarboxylate is a new developed antiwear additive and was applied to lubrication oil in this study. This lubrication oil was tested in the real engine environment by using 100-hr engine bench tests.

The amount, type and addition conditions of additives of lubricants should be continuously adjusted to obtain appealing performance. To obtain the optimal pretreatment parameters and reduce the cost of time-consuming experiments, the purpose of this paper is to establish an optimal back propagation neural network (BPNN) model combined with genetic algorithm (GA) in this work.

Using trimethylolpropane trioleate as the base oil and three types of phosphorus compounds as additives, 25 sets of lubricant formulas were designed regarding lubricant performances of average friction coefficient, average spot diameter, disk wear volume and extreme pressure. The data set was used for training and learning of BPNN and then combined with GA to optimize BPNN with continuously optimization by adjusting various parameters.

Comparing prediction data of BPNN with actual test data, correlation coefficients were above 90%, indicating that the model could accurately predict the performance of lubricants. When combined with GA, all performance errors were less than 5%, indicating that BPNN could be optimized by GA to obtain an accurate combined model for prediction of lubricant performance. The best additive formula with excellent performances was obtained from the BPNN–GA model.

This work developed a new method to study lubricant compounding. The combined model was expected to provide a theoretical basis and guidance for the compounding optimization of lubricant additives with high efficiency and low cost and to expand the scope to practical applications.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2020-0165/

The paper aims to address the formulation of zirconium and oxalicum additive-based lubricants for use in slide ways to meet the demands of high positioning exactness based on reduction in stick–slip and coefficient of friction over a wide speed range and compares the same with commercially available lubricant.

An investigation into the frictional properties and stick-slip behavior of lubricating oil is carried out using linear reciprocating tribometer and correlated with ultraviolet spectroscopic analysis.

It is observed that these transition metal additive compounds support in increasing the flexibility of the molecular chains leading to improved lubricity.

The lubricant additives considered for the current study are based on transition metals zirconium and oxalicum. It is observed that these additive compounds support in increasing the flexibility of the molecular chains, leading to improved lubricity.

The purpose of this paper is to study the antirust, tribological performance and anti-wear (AW) mechanism of the of soybean lecithin (SL) as a kind of multifunctional lubricant additive.

As a kind of multifunctional lubricant additive, the antirust performance of SL was tested according to ASTM D 665, and meanwhile, its tribological performances were also evaluated by Optimol SRV-I oscillating reciprocating friction and wear tester and four ball tester. The worn steel surfaces were investigated by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS).

The results showed that the SL exhibited excellent antirust properties in different base stock, and could effectively improve the AW and extreme pressure (EP) performances. The results of SEM and XPS indicated that a protective film was formed between steel-steel friction pair during the tribological test.

This paper first investigated the antirust properties and the tribological mechanism of the SL as a kind of multifunctional lubricant additive, which can be very useful and will promote the application of SL in lubricant industry.

This study aims to evaluate and compare by 100 hours engine bench tests the tribological performances of two types of lubrication oils, which were sulfur-based, boron succinimide-containing antiwear package (NP-3) oil and conventional zinc dialkyldithiophosphate (ZDDP)-containing (R-1) oil.

The tribological performances of the oils were evaluated in three main contexts, including engine tests, physical/chemical changes and surface analysis.

Results showed that NP-3 lubrication oil, which was environment- and catalyst-friendly, can be an alternative lubrication oil with its tribological performance due to similar antiwear characteristics with the ZDDP.

Attempts to develop catalysis- and environment-friendly antiwear additive packages have not presented popular or commonly used ZDDP-free products for the vehicle industry. This study presents tribological characterization of a newly developed ZDDP-free lubricating oil by engine bench tests.

Zinc dialkyldithiophosphate (ZDDP) is the most common anti-wear and anti-oxidant additive. ZDDP is the primary origin of zinc, sulfur and phosphorus, which are well-known poisonous elements for commercial after-treatment systems. The aim of this study is to investigate the optimum oil drain interval of non-phosphorus and non-ash (NPNA) engine oil that was developed as a prospective alternative to commercial phosphorus-containing (PC) engine lubricants.

The results of a fleet test wear debris analysis were used to optimize the oil drain intervals from the perspective of cost.

Drain intervals of 32,000 and 28,000 km were computed as the optimum values for NPNA and PC engine oils, respectively. Extending the oil drain intervals up to the obtained mileage may go to a total saving of €43,045,084.2 for PC engine oil and €49,253,998.6 for NPNA engine oil with respect to the total sales figures of test vehicles in Turkey.

Maximizing the lubricant life has environmental benefits and is the easiest way to reduce the maintenance cost of a vehicle. The protection of after-treatment systems against lubricant-induced poisoning is a great challenge. The most important result of this investigation is the lower operation costs of catalyst-friendly lubricants in spite of their low anti-wear additive performance.

The purpose of this paper is to investigate the tribological properties of novel phosphorous-nitrogen (P-N) type additives in water.

The tribological properties of the novel P-N additives in water are compared with a commercial lubricant additive of the P-N type using a four-ball machine. The tribological mechanism was investigated by X-ray absorption near-edge structure (XANES) spectroscopy.

The experimental results indicate that the phosphoramidate derivatives possess good anti-wear and friction-reducing properties. The XANES analysis shows that the prepared compounds can form a protective film containing phosphate and/or polyphosphate that affects the tribological behavior.

The purpose of this paper is to investigate the tribological properties of the novel P-N type additives in water.

This paper aims to investigate the layer of material deposited on a sample of acrylic resin by electroless nickel plating process. Acrylic resin is a popular material in rapid prototyping (RP) which uses the additive manufacturing technique to build prototypes for visual inspection, assembly, etc. Metallization of the RP materials can extend application envelop of RP techniques, as they can be used in decorative or functional applications.

Unlike electroless nickel plating on a metal substrate, the plating process for an acrylic resin substrate is different, as there is no metal ion for the auto-catalytic electroless reaction. Pre-treatment processes are performed on an acrylic resin sample to initiate electroless nickel plating. The morphology, chemical composition and structure of the layer deposited on the sample are examined using scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction.

The investigation shows that a nickel phosphorous alloy layer is plated on to the substrate surface of the acrylic resin sample.

Plating a layer of nickel phosphorous alloy layer on an acrylic resin RP material can widen the application of RP technology. An application of nickel plated acrylic resin sample to rapid tooling for low-volume production plastic parts is presented.

This paper seeks to study the tribological properties, corrosion inhibition properties and action mechanism of two triazine‐containing disulfides, TOSS and TOMA, as additives in combustion engine base oil (5CST); those properties of an alkyl disulfide dodecyl disulfide and zinc dialkyldithiophosphate (ZDDP) were also evaluated for comparison to discover whether these additives could be used as potential substitute candidates for ZDDP.

Their tribological performances were evaluated using a four‐ball machine. The worn surfaces were investigated by scanning electron microscopy and X‐ray photoelectron spectroscopy (XPS)

The three additives have good load‐carrying capacity and corrosion inhibition properties comparable with those of ZDDP. The anti‐wear properties of the triazine‐containing disulfides TOSS and TOMA are good but a little inferior to those of ZDDP. The friction‐reducing performances of the additives are better than those of ZDDP. The XPS results show that absorption and tribochemical reactions occur to generate a complex boundary lubrication films comprising inorganic sulfate, sulfide, iron oxide and organic nitrogen, and sulfur‐containing compounds.

The anti‐oxidation properties are still to be estimated, and the synergistic effectiveness with other additives could be demonstrated.

These additives are good extreme pressure and anti‐wear additives in combustion engine base oil and, through further modification of molecular structure or combination with other additives, they may be a potential replacement for ZDDP.

To reduce the cost, the products synthesized were not finely separated. Their tribological properties as additives in the widely used combustion engine base oil were first investigated and results indicate that they show excellent performances.