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The purpose of this paper is to describe very reproducible boundary lubrication tests, conducted as part of design of experiment (DOE) to study the behavior of fluorinated catalyst mixed with polutetrafluoroethylene or Teflon (PTFE) in developing environmentally friendly (reduced P and S) anti‐wear additives for future engine oil formulations. The paper presents both the statistical and experimental solution to the fluorinated interactions in fully formulated (F‐fully formulated) and plain ZDDP (F‐plain) oils.

The wear performance of fluorinated additive in combination with conventional commercial oil and ZDDP plain oil were investigated using DOE software. Several chemistry combinations were prepared and tested under extreme boundary lubrication (385 N with maximum Hertzian contact pressure of 2.72 GPa). Wear and frictional properties were evaluated using DOE and the interactions of fluorinated mix with minimum phosphorus were studied and compared with respect to fully formulated and plain ZDDP oils.

The optimized desirability shows the best condition that leads to more consistency in the breakdown of the tribofilm for a fixed contact load and fixed amount of fully formulated ZDDP oil. The influence of catalyst and PTFE fluorinated mix were examined. Scanning electron microscopy with chemistry analysis was developed. Hardness of the tribofilms, X‐ray of the wear track and Auger spectroscopy confirm the present of fluorine and phosphorus.

To ensure the reliability of the model, two original tests were conducted on the fully formulated and plain oil with minimum fluorinated mix.

The purpose of this paper is to study the friction and wear performance of two plain ZDDP oils in the presence of fluorinated catalyst and PTFE combinations under extreme boundary lubrication of 385 Newton load (Hertzian contact pressure of 2.72 GPa). The mechanism of tribofilm formation and breakdown was followed carefully by monitoring the friction coefficient over the duration of the test.

Very reproducible boundary lubrication tests were conducted as part of design of experiment (DOE) to study the behavior of two different fluorinated plain oils in developing environmentally friendly (reduced P atd S) anti‐wear additives for future engine oil formulations. Friction and wear performance of ZDDP plain oils improve in the presence of fluorinated mix combinations. In order to understand the wear mechanism, different factors of chemical compositions and different wear responses were analyzed and optimized using DOE. Several chemistry combinations were prepared and tested under extreme boundary lubrication.

The interactions of fluorinated mix with minimum phosphorus were studied and compared. Tribofilms with thickness ranging from 300‐400 nm were developed during wear tests and were analyzed for two fluorinated plain oils that target reducing phosphorus.

The influence of catalyst and PTFE fluorinated mix were examined. Scanning electron microscopy with chemistry analysis was developed. Hardness of the tribofilms, X‐ray of the wear track and Auger spectroscopy confirm the present of fluorine and phosphorus. The two repeated tests that were conducted on both plain oils with minimum fluorinated mix confirm the prediction of the DOE model.

This paper aims to focus on the topics of phosphorus (P) and sulfur (S) in engine oil. Very reproducible boundary lubrication tests were conducted as part of Design of Experiments software to study the behavior of fluorinated catalyst iron fluoride (FeF3) and polytetrafluoroethylene (PTFE) in the development of environment-friendly (reduced P and S) anti-wear additives for future engine oil formulations. Multi-component fully formulated oils were used with and without the addition of PTFE and fluorinated catalyst to characterize and analyze their performance.

A boundary lubrication protocol was used in the DOE tests to study their tribological behavior. Lubricant additives like PTFE and FeF3 catalyst were used at different concentrations to investigate the wear resistance and the time for a full breakdown under extreme loading conditions. Experiments indicated that new sub-micron FeF3 catalyst plays an important role in preventing the breakdown of the tribofilm.

This paper explores the effect of PTFE and FeF3 catalyst on the performance of fully formulated engine oils. The purpose was to develop equations for minimum wear volume and maximum time for full breakdown. Emphasis was, therefore, given to conditions where the additives were working effectively for minimizing zinc dialkyl dithio phosphate (P per cent). Lubricating oils are normally multi-component additivated systems. They contain different additives such as viscosity improvers, detergents, dispersants and antioxidants. It is known that these additives interact at the surface, affecting the function of the lubricating oil. Therefore, it is important to note that the performance with PTFE and FeF3 catalyst was significantly improved when compared to fully formulated commercial oils used alone.

Lubricating oils are normally multi-component additivated systems. They contain different additives such as viscosity improvers, detergents, dispersants and antioxidants. It is known that these additives interact at the surface, affecting the function of the lubricating oil. Therefore, it is important to note that the performance with PTFE and FeF3 catalyst was significantly improved when compared to fully formulated commercial oils used alone.

This study aims to examine the effect of the antiwear resistance of plain zinc-dialkyldithiophosphate (ZDDP) oil in the presence of Titanium-fluoride/iron-fluoride/polytetrafluoroethylene (TiF₃/FeF₃/PTFE) in the time to tribofilm breakdown and extent of wear under extreme boundary lubrication using a contact load of 317 Newton and a rotational speed of 700 rpm to simulate the cold start of a car engine. The mechanism of tribofilm formation and breakdown was followed carefully by monitoring the friction coefficient for different surface roughnesses over the duration of several reproducible tests that were performed in a ball on cylinder tribometer.

The heating time of the cylinder dipped in the specified lubricant blend then set for one minute before testing and the break in period of 2 minutes to cool the contacting metal to metal surfaces during tribological testing played important roles in minimizing friction and wear, and are directly proportional to the durability and time for breakdown of the tribofilm. This article addresses the improvement of water drop contact angles for different surfaces during heat treatment and the tribological enhancement of antiwear additives when optimum concentration of fluorinated catalysts and PTFE is used in connection with reduced surface roughness and break in period.

Design of Experiment software, scanning electron microscopy, energy dispersive spectroscopy and nanoindentation were used in this study to evaluate the antiwear resistance films when using 0.05 per cent phosphorus ZDDP plain oil with 0.5 weight per cent TiF3 + 0.5 weight per cent FeF3 + 2 weight per cent PTFE and when applying 2 minutes break in time to cool down the contacting bodies when temperature rises. Results indicated that the coated film on the thermally treated surfaces that is reflected as white patches on the SEM images is a function of the antiwear additives contribution; it is also shown to have positive influence on the friction and wear performances during tribological testing.

This research involved the study of lubricant and surface interactions with antiwear additives under boundary lubrication and extreme pressure loading. Several researchers studied these effects and submitted articles to the journal. This is the first time that a break in period was used with surface conditions to simulate car stops in heavy traffic conditions.

The growing range of EEC Directives and Regulations for food products, some of which have never been subject to statutory control in this country, with compositional standards, and in particular, prescribed methods of analysis — something which has not featured in the food legislative policies here — must be causing enforcement authorities and food processors to think seriously, if as yet not furiously. Some of the prescribed methods of analysis are likely to be less adaptable to modern processing methods of foods and as Directives seem to be requiring more routine testing, there is the matter of cost. Directive requirements are to some extent negotiable — the EEC Commission allow for regional differences, e.g., in milk and bread — but it has to be remembered that EEC Regulations bind Member‐states from the date of notification by the Commission, over‐riding the national law. Although not so frequently used for food legislation, they constitute one of the losses of sovereign power, paraded by the anti‐market lobby. Regulations contain usual clauses that they “shall enter into force on the day following publication in the Official Journal of the European Communities” and that they “shall be binding in their entirety and directly applicable in all Member States”.

Loading condition and minimizing friction and wear using molybdenum disulfide grease in aircraft engine bearings are the focus of this research. The relationship between the milled and unmilled MoS₂ (molybdenum disulfide) greases to its tribological properties, such as coefficient of friction, wear and chemical-mechanical properties of tribofilms, is examined for constant extreme pressure loading and spectrum or actual loading.

In this study, the design of experiments (DOE) approach was used to analyze the different loadings and speeds at a specific duration of 36,000 revolutions to examine the lithium base grease wear behavior with milled and unmilled MoS₂ powder. Load is treated as variable that simulates actual conditions under 1,200 and 600 rpm rotational speeds using the four-ball test with chromium steel ball bearing aircraft grade E52100.

The results indicated that ball-milled MoS₂ grease tests showed reduction in wear and friction under all conditions, especially spectrum or actual loading. Unmilled MoS₂ powder exhibited worse wear outcomes than the milled one. The SEM and AES analyses indicated that a tribofilm is formed on the wear surface of the milled powder grease, especially at variable loading and initially at lower loads in the ramp-up tests that significantly enhanced the contact characteristics and prevented abrasion at higher loads.

This research indicated that the wear resistance in actual loading might be due to frictional heating generated during the ramping-up conditions where it provided a protective film that enhanced the steady-state friction for the duration of the test. Several researchers used ASTM standards to work on constant loading conditions. This is the first time that reduced milled MoS₂ powder showed significant improvement in grease performance.