With the development of industrial technology, the high-speed, high-performance, high-automation, high-efficiency, and long-life required by modern equipment can no longer be satisfied by simply using mineral oil lubricating materials in terms of lubrication.

What is oil additive?

Adding a small amount of other substances to the lubricating material can improve its performance and give it new characteristics. These substances are called oil additives.

Adding different additives to oil is the most economical and effective means to improve oil quality. Generally speaking, the variety and quality of lubricants often depend on the variety and quality of additives. Therefore, the development of the production and use of additives has become an important way to rationally and effectively utilize resources, improve equipment performance and save energy.

Lubricating oil additives can be divided into detergents and dispersants, antioxidants and anticorrosives, extreme pressure antiwear agents, oily agents and friction modifiers, antioxidants and metal deactivators, viscosity index improvers, rust inhibitors, and anti-wear agents. Grouping of coagulants, anti-foaming agents, etc., the following describes the mechanism of action of commonly used lubricant additives.

What is a detergent and dispersant

Detergent dispersant includes two types of detergent and dispersant. Mainly used in internal combustion engine oil (steam engine oil, diesel engine oil, railway diesel locomotive oil, two-stroke engine oil and marine engine oil). Its main function is to keep the inside of the engine clean, so that the insoluble matter generated is in a colloidal suspension state, and it will not further form carbon deposits, paint film or sludge. Specifically, its role can be divided into four aspects: acid neutralization, solubilization, dispersion and washing.

(1) Acid neutralization

Detergent dispersants generally have a certain degree of alkalinity, and some are even highly alkaline. They can neutralize the organic and inorganic acids generated by the oxidation of lubricating oil to prevent further condensation, thus reducing the paint film and preventing these The corrosion of acidic substances on engine components.

(2) Solubilization

Detergents and dispersants are all surfactants, which can solubilize solid or liquid substances that cannot be dissolved in oil in the center of micelles composed of 5-20 surfactant molecules. During use, it Solubilize oxygen-containing compounds containing hydroxyl, carbonyl and carboxyl groups, nitro compounds, moisture, etc. into micelles to form colloids to prevent further oxidation and condensation and reduce the formation and aggregation of harmful deposits on engine parts.

(3) Dispersion

It can absorb small solid particles such as carbon deposits and paint films that have been generated, and make them dispersed in the oil in a colloidal solution state, preventing these substances from further agglomerating into large particles and adhering to the machine parts, or depositing as sludge.

(4) Washing effect

It can wash off the paint film and carbon deposits that have been adsorbed on the surface of the component, and disperse it in the oil to keep the engine and metal surfaces clean.

The structure of the detergent dispersant is basically composed of lipophilic, polar and hydrophilic groups. Due to the difference in structure, the performance of the detergent dispersant is different. Generally speaking, the detergency of the ash additive is better. Well, the dispersibility of ashless additives is outstanding.

Typical representative of detergent and dispersant

Typical representatives of detergent dispersants are sulfonates, alkylphenates, salicylates, succinimides, succinates and polymers. The first three are also called ash-free detergent dispersants, and the latter three are called ash-free detergent dispersants.

Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. Contact us.

What is extreme pressure antiwear agent?

In boundary lubrication, when the metal surface is only under moderate load, if there is an additive that can be adsorbed on the metal surface or wears violently with the metal surface, this additive is called an anti-wear additive. When the metal surface is subjected to a high load, a large number of metal surfaces are in direct contact and a large amount of heat is generated, and the film formed by the anti-wear agent is also destroyed and no longer protects the metal surface. If there is an additive that can interact with the metal surface The chemical reaction generates a chemical reaction film, which acts as a lubrication to prevent metal surface scratches and even fusion welding. This most demanding boundary lubrication is usually called extreme pressure lubrication, and this additive is called extreme pressure additive.

Chlorine extreme pressure antiwear agent

Chlorine-containing extreme pressure anti-wear agent has low price and good performance. It has good compounding effect with phosphorus and sulfur-containing additives. It is one of the earliest extreme pressure anti-wear components used in the lubricant industry. Commonly used chlorine-containing extreme pressure antiwear agents are aliphatic chloride and aromatic chloride. The use effect of chlorine-containing extreme pressure antiwear agent mainly depends on its molecular structure and the chemical activity of chlorine atoms. When the chlorine atom is at the end of the aliphatic hydrocarbon, the activity is the highest, and the extreme pressure antiwear performance is the best; when the chlorine atom is in the middle of the carbon chain, the activity is second; when the chlorine atom is on the carbon ring, the activity is the worst, and the corresponding extreme pressure antiwear performance is The weakest. Therefore, aliphatic chlorides have poor stability, strong chemical activity, and good extreme pressure and anti-wear properties, but they are easy to cause metal corrosion, such as Chlorinated Paraffin; aromatic chlorides have good stability, low chemical activity, and extreme pressure resistance. The abrasiveness is poor, but the corrosiveness is less, such as Pen-tachlorobiphenyl (Pen-tachlorobiphenyl).

In recent years, as people’s awareness of environmental protection has been gradually strengthened and environmental protection regulations have become increasingly strict, the use of chlorine-containing additives has gradually decreased due to toxicity and corrosive problems. For example, chlorine-containing gear oils have been replaced by sulfur-phosphorus gear oils. 

Sulfur-containing extreme pressure antiwear agent

Studies have shown that the extreme pressure and antiwear properties of sulfur-containing compounds are closely related to the C-S bond energy in their molecular structure. The smaller the C-S bond energy, the easier it is to break and form a protective film during the friction process, resulting in a better extreme pressure and anti-wear effect. The mechanism of action of the sulfur-containing extreme pressure antiwear agent is to first adsorb on the surface of the friction pair to reduce the friction between the friction pairs; as the load increases, the contact temperature between the friction pairs rises rapidly, and the sulfur-containing compound reacts with the metal to form sulfur The iron alcohol film has an anti-wear effect; with the gradual increase of the load, the CS bond begins to break, forming an extreme pressure chemical reaction film of FeS, which has the effect of anti-abrasion and anti-sintering.

Due to the high melting point of iron sulfide (1193℃-1199℃), it has good heat resistance effect, and sulfur-containing extreme pressure antiwear agent has very high sintering load. However, the iron sulfide film does not have the layered structure of graphite, molybdenum disulfide, ferric chloride, etc., and its anti-friction performance is poor. At the same time, although the iron sulfide film has high melting point and hardness, its brittleness is also high. In addition, considering the sulfur content The compound has strong corrosive wear, so the anti-wear performance of sulfur additives is poor.

The iron sulfide film formed by sulfur additives in the friction process has a high melting point and good extreme pressure performance. It is suitable for use under severe conditions such as high temperature and high load. It is a commonly used extreme pressure and antiwear additive in lubricating grease. At present, commonly used sulfur-containing extreme pressure antiwear agents mainly include sulfurized olefins, sulfurized oils (esters), polysulfide compounds, dibenzyl disulfide, and xanthogenic acid.

Phosphorus-containing extreme pressure antiwear agent

Phosphorus-containing additives have multiple functions such as extreme pressure, anti-wear, anti-friction, and anti-oxidation. They have good thermal stability, low corrosivity, and good compounding effects with other functional additives. They have been widely concerned by researchers and have developed rapidly in recent years. . There are also different opinions on the mechanism of action of phosphorus additives. Early scholars believed that phosphorus-containing compounds decomposed under the action of the instantaneous high temperature at the raised points of the friction surface, and formed iron phosphide with iron, and then formed the low-melting co-fusion gold with iron to flow to the recesses, smoothing the friction surface and preventing wear. Call this effect "chemical polishing". In recent years, some scholars believe that under boundary lubrication conditions, phosphide and iron do not produce iron phosphide, but a mixture of iron phosphite.

Phosphate is first adsorbed on the iron surface, and then the C-O bond breaks under boundary conditions to form iron phosphite: or iron phosphate organic film, which plays an anti-wear effect; under extreme pressure conditions, the organic iron phosphate film further reacts to form inorganic The iron phosphate reaction film prevents direct contact between metals, thereby protecting the metals and acting as extreme pressure. The variety of phosphorus-containing additives is more complex, not only in the type of compound, but also in the element composition. Some contain a single element of phosphorus, some contain sulfur and phosphorus, and some contain sulfur, phosphorus, nitrogen and other elements. Even if the element composition is the same, the compound structure can be different, and different phosphorus compounds are used for different purposes. Generally, phosphorus-containing additives can be roughly classified into phosphorus type, phosphorus nitrogen type, sulfur phosphorus type, sulfur phosphorus nitrogen type, phosphorus nitrogen boron type, sulfur phosphorus/sulfur phosphorus nitrogen boron type, etc. according to the active elements therein.

Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. Contact us.

What is dry lubrication?

Dry film lubrication is to form a solid lubricating coating on the surface of the friction pair by means of physical deposition, chemical reaction or evaporation deposition, so that friction occurs between the lubricating coatings, so as to achieve friction reduction and wear resistance. Solid coatings include polytetrafluoroethylene (PTFE), DLC film, MoS2 coating and so on. The solid lubricating coating can be prepared on the surface of the friction pair of different materials (metal, paper, wood, rubber, plastic, glass, etc.) to form a uniform lubricating film, and at the same time play a role in waterproof, moisture-proof, corrosion-proof and cleaning.

What is PTFE coating?

In order to prevent the fasteners of mechanical equipment from corrosion and rust, many manufacturers choose some anti-corrosion coatings to deal with it. However, compared with conventional anti-corrosion materials, PTFE coatings can be applied in relatively harsh corrosive environments and have a type of anti-corrosion material that can achieve a longer protection period than conventional anti-corrosion coatings.

PTFE coating has excellent heat resistance and low temperature resistance. It can be used at -255℃~290℃, and can withstand high temperature to 300℃ in a short time. Generally, it can be used continuously between 240℃~260℃. The thermal stability, it can work at freezing temperature without embrittlement, and does not melt at high temperature.

PTFE coating can make fasteners have better anti-corrosion ability, avoid bolt rusting and delay the failure cycle, and make installation and disassembly easier. Excellent performance in harsh corrosive environments, so it is widely used in the surface anti-corrosion treatment of fasteners in petrochemical, nuclear power, electric power, natural gas and offshore oil platforms, and underwater equipment. After testing: In the ASTM B-177 salt spray test, the PTFE coating lasted for 2500 hours, and the red embroidery area was less than 15%, which achieved excellent results.

The insulation strength of the PTFE coating can reach 500-1200 volts per microinch (mil), thereby achieving the effect of inhibiting electrochemical corrosion. In addition, the PTFE coating has superior UV resistance and weather resistance, and can also prevent the corrosion of fasteners caused by hot soil layers and most chemicals.

PTFE coating has excellent lubrication performance, the friction coefficient can be as low as 0.05, and it can provide long-term lubrication for rotating workpieces under high pressure, and can reduce the installation torque to a certain extent, thus prolonging the service life of the workpiece.

The ptfe coating hardly adheres to all substances, and the thin film also shows good non-adhesion performance. Therefore, the workpieces treated with this coating are basically free of water and oil, even if there is a small amount of dirt, it is simple It can be removed by wiping, thus saving man-hours and improving work efficiency.

PTFE dry lubrication has the following characteristics:

(1) Clean, colorless, and oil-free, suitable for clean keyholes, plastic tracks, window and door tracks, zippers, tools, plastic chains, office equipment, toys, home appliances, auto parts, medicine, etc;

(2) High temperature resistance, no soft flow at high temperature, suitable for injection mold thimble, switch components, home appliances, electronic equipment, optical instruments, etc;

(3) Resistant to oil, water, and other chemical acid and alkali liquid corrosion, high adhesion, suitable for food and beverage, chemical equipment, paper industry, wood, textile and packaging industries;

(4) Lubrication in vacuum environment, such as laminator rails;

(5) Good lubrication performance, can provide long-lasting protection against friction and wear, extend the service life of parts and equipment, and improve their working efficiency.

Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. Contact us.

Tungsten disulfide powder

Tungsten disulfide WS2 is a layered crystal structure with excellent lubricity and extremely low friction coefficient. The dynamic friction coefficient is 0.030, and the static friction coefficient is 0.070. It is coated on the surface of auto parts, which can significantly reduce wear and seizure. Or reduce equipment repair and maintenance problems caused by friction, wear, etc., improve the work efficiency and service life of auto parts, and save time and cost for users. The chemical properties of tungsten disulfide are relatively stable, which can adapt to various too harsh conditions, provide maximum protection against wear, rust and corrosion, and is environmentally friendly. It is non-toxic and will not harm human health. The environment is polluted.

Tungsten disulfide oil additives

Tungsten disulfide is a new type of lubricating material with excellent anti-wear and anti-friction properties. It is recognized by the scientific community as one of the raw materials with the best friction and lubrication effect. The decomposition temperature of tungsten disulfide in the atmosphere is 510℃, and it oxidizes rapidly at 539℃. It can be lubricated for a long time at 425℃. The decomposition temperature in a vacuum is as high as 1150℃. Its extreme-pressure strength can reach 21MPa. The radiation performance is better than that of molybdenum disulfide, graphite, fullerene and other materials. It can not only adapt to general lubrication conditions but also can be used in harsh working environments such as high temperature, high pressure, high load, high vacuum, corrosion and radiant media. Therefore, tungsten disulfide has been used as a high-performance solid lubricating material in aerospace, military and other high-tech fields.

Tungsten disulfide greases

Lithium-based grease containing tungsten disulfide powder with different mass fractions, at the optimal addition amount of 2% by a mass fraction, lithium-based oil exhibits the best tribological performance non-seizing load and sintering load are respectively compared with the base Grease increased by 112.8% and 84.3%. The average friction coefficient and wear scar diameter decreased by 17.3% and 46.8%, respectively.

During the friction process, part of the tungsten disulfide powder is adsorbed and deposited on the pits of the friction pair due to the nano-scale effect, which plays a role in surface repair; at the same time, under high temperature and high load conditions, a WS2 nanoparticle absorbent layer is formed, and tungsten disulfide nanopowder It chemically reacts with the surface of the friction pair to create a chemical reaction film containing Fe2O3, FeSO4, WO3 and Fe3O4, thus exerting an excellent lubricating effect.

Here are a few examples of tungsten disulfide applications in the automotive industry

When the car engine is running, the temperature will be very high, and the piston will rotate back and forth at a very high speed. Operating under such harsh conditions, the piston will accelerate wear. Due to the low coefficient of friction of tungsten disulfide, the lubricating effect can be maintained for parts used for high temperature or heavy load friction. At this time, coating it on the surface of the piston will reduce wear, lower temperature and extend service life.

The crankshaft is an essential part of the engine. Its working condition is also high-speed rotation, so it must be resistant to wear and fatigue. The surface of the journal is generally high-frequency quenched or nitrided, and its surface is coated with tungsten disulfide and finely ground. Its wear resistance and fatigue strength will be significantly improved.

The universal joints, steering knuckles, spring steel plate bushes, and front and rear brake cam bushes in automobiles are relatively challenging to apply oil. With the infrequent operation, the lubricating oil used will deteriorate and lose its lubricating effect. Tungsten disulfide has excellent mechanical stability and thermal stability, ensuring that these parts enjoy the lubricating effect and reduce wear.

Tungsten disulfide has excellent compatibility, water erosion resistance, and affinity with most paints, solvents and fuels. It can ensure that there is always a layer of the lubricating layer on the surface of the bearing in the water pump and the silicon oil fan clutch and the spiral gear of the driving distributor so as to protect against rust and corrosion. With such excellent properties, tungsten disulfide can be used not only in the automotive industry but also in the machinery industry, plastics industry, medical device industry, military, aerospace, satellites, and aviation spacecraft.

Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. Contact us.

What is graphene?

Graphite and diamond are the most widely known allotropes of the C element. In 2004, Professor Andre and Researcher Christine of the University of Manchester used scotch tape to paste and tear high-orientation graphite repeatedly. It was the first time to prepare and prove the existence of graphene. The two scholars also won the 2010 Nobel Physics Award Academic awards. The theoretical thickness of a single-layer carbon nanomaterial is only 0.34 nm, which has become another focus of enthusiasm for scientists in many fields after fullerenes and carbon nanotubes.

Anti-friction and anti-wear properties of graphene additives

Graphene has a unique two-dimensional nano-layered structure, high mechanical strength and strong thermal conductivity. Graphene is the basic structural unit of carbonaceous solid lubricating materials, and its nanotribological properties are affected by many factors. Although the number of layers is different in the academic circles, the influence of the number of layers on its surface friction is the most obvious.

Through the research of graphene nanotribological properties, it can be concluded that graphene has a high-quality lubricating effect and high anti-wear properties, so graphene has the potential of high-quality nano-lubricating materials.

(1) Graphene is used as an anti-sticking and anti-friction protective film for micro and nanodevices of various materials. Various graphene-based nano lubricating films reduce the friction coefficient of the substrate surface and extend life.

(2) Graphene is used as an additive for lubricating oil, ionic liquid and water lubrication. It can form a frictional adsorption film and a second transfer film on the friction interface, preventing the direct contact of the second friction surface, thereby improving the bearing capacity of the lubricant and friction. The anti-wear performance of the vice is better.

(3) Graphene is used as a filler for polymers, ceramics and other materials. Graphene makes the mechanical properties of the matrix material better. It uses a continuous transfer film to reduce the friction coefficient of the polymer matrix and dramatically improves the wear resistance of the matrix material. The constant transfer film has self-lubricating and high bonding characteristics.

The structure of graphene is densely layered, which gives it the particular properties required by wear-resistant materials, such as better thermal stability, lower shear strength, and more insufficient surface adhesion. Besides, its ultra-thin sheet structure can quickly enter the contact surface to reduce direct contact between two rough surfaces. Therefore, graphene can be added to lubricants as a friction modifier.

The lattice commensurability between graphene layers determines the nano-friction between the layers. Due to the incommensurability, the sliding friction between the layers formed by the stack is minimal, and even super-lubrication may occur. All these make graphene possess the characteristics of high-performance oil additives. Studies have shown that using an appropriate amount of graphene additives as nano sliding bearings can reduce the friction coefficient and significantly increase the load-bearing and anti-wear properties of lubricants utilizing friction adsorption films. The unique properties of graphene have made it a hotspot for research in many fields, and it has shown a more comprehensive application prospect.

Dispersion stability of graphene additives

Graphene's super-flake layer structure, superior mechanical properties, and self-lubricating properties make it a heat-carrying and anti-wear stuff studied in many fields. However, graphene tends to agglomerate in lubricating oil or water, making its dispersion in solvents unstable. Currently, there are two main methods for solving graphene dispersion. First, add points. Various studies have found that using the right amount of graphene as a lubricating additive can reduce the friction coefficient and significantly increase the dispersant. Utilize the dispersing effect of dispersant to make it evenly and stably dispersed in lubricating oil and water. The disadvantage is that the dispersant may affect the tribological properties of graphene; second, functional modification. The stability of graphene dispersion in lubricating oil or water is enhanced. The key to this method is the choice of active molecules.

The main problems in the development of graphene additives

Due to the advantages of graphene's good thermal stability, low shear strength, and low surface adhesion, its application in tribology has attracted more and more attention from scholars at home and abroad. The application prospects of enhancing heat transfer and improving lubricating friction have significantly been improved—the attention and recognition of experts and scholars in most fields. Many related companies and research institutions have invested a lot of energy in the research and development of graphene lubricants. However, the current research on graphite and functionalized graphene as lubricating materials are still in the early stage, and there are still a lot of problems to be solved:

(1) Many scholars have done a lot of research on graphene agglomeration and formed the leading solution. However, under different graphene specifications, there is a large gap in modification methods and conditions, requiring many experiments to support. And the current research is mostly focused on high-quality graphene, and the price of high-quality graphene is relatively high. It is challenging to apply it to lubricating oil on a large scale under current circumstances. However, there are few studies on the modification of low-quality multilayer graphene. It is challenging to ensure the dispersion stability of graphene in lubricating oil while maintaining the inherent mechanical and tribological properties of graphene. The actual modification of the problem remains to be further studied.

(2) When graphene with different microscopic morphology and other layer specifications is used as a lubricant additive, the tribological properties are also other. When the number of graphene layers is within 30 layers, the anti-friction and anti-wear performance of graphene lubricant additives must be verified by experiments.

(3) Experimental research on the nano-friction and nano-wear mechanisms of various functionalized graphenes remains to be carried out, such as oxidation, nitridation, fluorination, silanization amination of functionalized graphenes exhibiting anti-friction and resistance Grinding performance is more to be explored.

It can be seen from the above that the lubricating oil added with graphene has significantly improved friction and anti-wear effects. However, most of these experiments are carried out on four-ball mills or friction and wear testing machines, and experiments that are carried out on engine benches are rare. In the real engine environment, the lubricating oil is at a higher temperature, pressure, and shear, so it needs to meet the effects of better lubricity, cooling, detergency, and corrosion resistance. Therefore, it is minimal to rely solely on the testing machine to determine the impact of nano-additives in internal combustion engine lubricants.

Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. If you are looking for graphene, please contact us.

Mechanism of nano friction reducer oil additive

A large number of experimental studies have found that as an oil additive, nanoparticles can effectively improve the lubrication state of the friction pair and reduce friction and wear. It is an ideal friction-reducing oil additive. However, due to the limitations of modern science and technology and experimental conditions, the research on the anti-friction and anti-wear mechanism of nano oil additives is still in its infancy. Only through the combination of macroscopic phenomena and theoretical analysis, the means for a particular category of nano additives can be proposed. The theory is narrower. There are three primary speculations about its mechanism of action.

(1) The viewpoints of adsorption, permeation and tribochemical reactions. 

Nano oil additive can effectively fill the uneven surface of the friction pair and form a "third body" by tribochemical response with the character, thus having an anti-wear effect.

(2) The "Molecular Bearing" view.

Nano oil additive is small in size and ball-like, and can roll freely between friction pairs to reduce friction resistance, lower friction coefficient, and reduce wear;

（3）The viewpoint of nanofilm.

Organic modifiers are used when modifying nanoparticles. The organic matter with tribological properties moves to the surface of the friction pair and forms a nanofilm during friction. The nanofilm has high toughness and strong bending resistance, thereby enhancing the friction pair: the anti-wear performance and self-lubricating performance.

As a nanomaterial for the Nobel Prize in Physics in 2010, graphene, known as "black gold" and "king of new materials", has excellent strength, flexibility, electrical conductivity, thermal conductivity and ultra-thin properties.

Critical role of graphene as nano friction reducer oil additive

(1) The friction coefficient is only 0.01

When the lubricating oil rich in graphene elements is injected into the oil tank, the graphene sheets will adhere to the friction surface of the cylinder and piston ring walls under the action of van der Waals force. A layer of "graphene film" is formed. Due to its sheet structure, the friction between the original metal and the metal can be changed to the conflict between the graphene sheets, and the friction coefficient of graphene is only 0.01, so The friction can be significantly reduced.

(2) Penetration technology

The high-temperature and high-pressure environment derived from the internal combustion chamber of the engine and the friction generated by the high-speed movement will make the metal atoms of the engine and the graphite carbon atoms adhering to the metal surface inside the machine become extremely active. Then the "carburization" reaction occurs. The carburized metal friction surface will form a "carburized layer" protective film, which can significantly improve the hardness, wear resistance, fatigue strength and corrosion resistance of the engine friction metal surface. To achieve the effect of significantly extending the service life of the engine.

Why does graphene lubricant save fuel?

（1）The graphene protective film formed by the graphene lubricating oil on the friction surface reduces the friction loss of the engine. The reduction of friction loss means the increase of the engine output power, which means that the fuel is saved under the same power output.

（2）The graphene protective film formed by the graphene lubricating oil between the engine cylinder and the piston is working. The graphene protective film here improves the tightness of the combustion chamber and burns more fully. The carbon monoxide, hydrocarbons, etc. in the exhaust gas Fully burned to form carbon dioxide and water. Carbon dioxide is an inevitable substance after combustion. It is not a pollutant component in the exhaust gas. The exhaust gas is naturally purified. At the same time, due to the sealing of the combustion chamber, the high temperature and high-pressure gas in the combustion chamber affect the engine lubricating oil pan. The oxidation and acid corrosion of the lubricating oil, and the oxidation of the lubricating oil is one of the main reasons for the failure of the lubricating oil. The oil change cycle of the oil is naturally extended to reduce friction, reduce noise, and extend the life of the engine and camshaft.

Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. If you are looking for graphene oil additive, please contact us.

What is friction modifier?

Friction modifier is an additive that reduces the friction coefficient of lubricating oil under boundary lubrication conditions. Its function is mainly to form a lubricating protective film on the metal surface to avoid direct contact between metal peaks so that the mixed lubrication and boundary lubrication conditions The friction coefficient is reduced, the friction resistance and wear are reduced, and the fuel-saving purpose is achieved.

Differential friction modifier includes carboxylic acids and their derivatives, amides, imides, amines and their derivatives, phosphorus and phosphoric acid derivatives, organic polymers, and organometallic compounds. Organometallic compounds are widely used in internal combustion engine oils. A class of products, such compounds include molybdenum dithiocarbamate (MoDTC), MoDTP, organic molybdenum mixtures, and so on. With the increase in environmental protection requirements, friction modifiers containing sulfur and phosphorus have been restricted. The role of environmentally friendly friction modifiers that do not contain metals, sulfur, and phosphorus is more prominent.

Type and working mechanism of friction reducer oil additive

1. Types and mechanism of organic friction modifier

(1) Types of organic friction modifiers

Usually, there is a polar group at one end of the organic friction modifier oil. This opposing group is one of the leading factors in the effectiveness of friction modifiers. From the chemical structure division, the commonly used organic friction modifier oil mainly includes ① carboxylic acid or its derivatives; ② imide, amine, and its products; ③ phosphorus or phosphonic acid derivatives; ④ organic polymers.

(2)what does friction modifier do?

The mechanism of action of organic friction modifier oil usually has the following three forms:

①Form a chemical reaction film. Such products mainly include saturated fatty acids, phosphoric acid, and thiophosphoric acid, and sulfur-containing fatty acids. The mechanism is similar to that of anti-wear agents. The friction modifier additive reacts with the metal surface to form a protective film, thereby reducing friction. But the most fundamental difference between the two is that the chemical reaction film of the friction modifier oil appears under milder load and temperature conditions in the mixed lubrication state, and the chemical activity of the friction modifier additive is required to be relatively high, such as a chemical structure similar to thrive. Stearic acid is an exception. In theory, as the temperature increases, the anti-friction effect of stearic acid should decrease due to the desorption of molecules from the metal surface. However, experiments have shown that with the rise in temperature, stearic acid forms a chemical reaction film, and the anti-friction effect is enhanced;

②Form a physical adsorption film. Such products mainly include long-chain carboxylic acids, esters, ethers, amines, amine-based compounds, and imides. The friction modifier additive dissolved in the oil is adsorbed on the metal surface by the polar groups of the molecules, and the long hydrocarbon chain is dissolved in the oil, perpendicular to the metal surface, resulting in a multilayer matrix of the friction modifier additive molecules. The thickness and anti-friction effect of the friction modifier additive film on the metal surface are related to the following parameters: (1) the more robust the polarity of the polar group, the greater the thickness and strength of the friction modifier film on the metal surface; (2) friction modifier The additive's hydrocarbon straight chain is conducive to the production of more muscular anti-friction cinema; (3) The chain length of the base oil and the chain length of the friction modifier additive are similar, which is beneficial to produce a stronger anti-friction film, but the chain length ratio of the friction modifier additive The chain length of the base oil has a more significant impact; (4) The increase in temperature can improve the thickness and strength of the friction modifier additive film, but if the weather is too high, the friction modifier molecules may be desorbed from the metal surface;

③Form a polymer. Such products mainly include unsaturated complex esters, methacrylates (esters), unsaturated fatty acids, and sulfurized kinds of paraffin. The formation of friction reducer oil additive is a particular case. It does not form a solid film but forms a liquid film under contact temperature and load, and the metal surfaces on both sides of the film do not react. The formation of this polymer requires the following characteristics: (1) Relatively low activity; (2) The polymer has good mechanical and thermal stability and is insoluble in the lubricating oil; (3) A healthy formation between the polymer and the metal surface Adsorption or chemical bond; (4) Polymer film formation speed is fast.

2. Other friction reducer oil additive types and their working principles

①Metal organic compound type friction reducer oil additive　　

Types of metal-organic compound friction modifiers mainly include molybdenum or copper compounds, such as molybdenum dithiophosphate, dithiocarbamate, copper oleate, salicylate or ester, and hydrocarbyl dithiophosphate Wait.

The mechanism of action of metal-organic compound friction reducer oil additive: (1) Molybdenum may penetrate into the rough surface, (2) form a polymer film, (3) form polymorphic molybdenum disulfide (the most acceptable theory), (4) A thin metal film that is easy to shear due to the selective transfer of metal (copper). The mechanism of action of metal-organic compound friction modifiers is not fully known.

②Non-oil-soluble friction modifier

The more classic non-oil-soluble friction modifiers are graphite, molybdenum disulfide, and the newly emerged Teflon (polytetrafluoroethylene), polyamide, graphite fluoride, borate, etc. The mechanism of action of this type of friction modifier is mainly to form a layered structure with a low shear rate or to form a ductile or plastic layer on the metal surface, resulting in a reduction in friction.

③The main difference of Differential friction modifier

Relatively speaking, the molybdenum-based metal-organic compound is very active in the boundary lubrication state, but the organic friction modifier is more involved in the mixed lubrication state.

The effect of organic friction modifier is more significant than the use of low-viscosity oil to compensate for the growth of mixed lubrication. To a certain extent, the molybdenum-based metal compound shows the same effect as the organic friction modifier. Still, the latter offers a small friction coefficient in the mixed lubrication state, especially under the most demanding low-speed and high-load conditions. The organic friction modifier mainly acts in the form of an absorption layer, which occurs at relatively low temperatures. The molybdenum compound acts as a polymer of MoS2 and needs to be present in a high-temperature environment. Besides, although molybdenum-based metal compounds can improve fuel economy, there are data showing that adding them to base oils or fully formulated engine oils increases TEOST deposit levels, which is undesirable.

Besides, although the molybdenum-based metal compound friction modifier is widely used in Japan and can improve fuel economy by 0.3%, the program VIB engine test limits its use. Therefore, it is more important to select a useful organic friction modifier to improve fuel economy.

 The improvement of the quality of internal combustion engine oil requires the development of related oil additives technology. To improve the performance of internal combustion engine oil, friction modifier plays a significant role. Its effect and research trends are mainly manifested in the following aspects:

(1) Strengthening of single-dose function and developing towards multi-function;

(2) The result of ashless additives and the enhancement of processes, replacing or partially replacing the current ash metal additives, such as nitrogen or boron compounds;

(3) The exploration of friction modifier to find more effective types of additives, especially the research of individual rare earth element (tungsten) additives, is expected to make good progress;

(4) Research on additives that can replace metal sulfophosphates to reduce the impact of phosphorus on engine systems;

(5) Research on adding Jing compound technology to meet better economic principles and comprehensive performance;

(6) The study on the action mechanism of a friction modifier guides people to better understand its action mechanism and apply it to actual internal combustion engine oil formulations.

Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. Contact us.

Dry lubricant is a kind of material that reduces the friction coefficient and reduces wear by preventing the friction parts from directly contacting under regular use or high load. Besides, the dry lubricant is also a key additive material for high-performance anti-seize agents and anti-wear coatings. It is often mixed in the form of powder particles in grease and lubricating oil to play a sliding role. The additives will fill up the rough surface of the accessories when the friction pair slides relatively. Therefore, under extreme operating conditions, dry lubricants provide sufficient boundary lubrication conditions, thereby achieving a reduced friction coefficient and reduced wear. Generally speaking, the advantages of solid lubricants are more evident than liquid lubricants under the terms of high vacuum below 10^-2 Pa and near atmospheric pressure above 10⁴ Pa, the low temperature below 0℃, and high temperature above 177℃.

Typical dry lubricant additives

Dry lubricant additives mainly fall into four categories: (1) carbon-based materials (such as graphite, DLCs, and nanocrystalline diamond); (2) transition metal disulfides (such as Mo S2 and WS2); (3) polymers (such as polytetrafluoroethylene) Fluoroethylene PTFE); (4) Ceramic high-temperature lubricating materials (such as metal oxides, metal fluorides, and sulfates). The first and second types of solid lubricating materials belong to the typical layered structure dry lubricant.

(1) Carbon-based lubricating material

Graphite is a typical carbon-based dry lubricant, which has the characteristics of high-temperature resistance and corrosion resistance.

And is famous for its reliable lubrication characteristics. The atoms in the carbon-based planes are bonded together by strong covalent bonds, and the base planes are combined by weak van der Waals forces, resulting in weak mechanical bonding between the aircraft. The presence of water vapor and oxygen in the environment can promote graphite.

Shear movement between crystal layers. When the base surface is worn, these active edges are neutralized (passivated) by adsorbing water or other steam. Graphite can also maintain low friction. This is for other carbon-based solid lubricants. Carbon-based lubricating materials also include various types of DLC coatings. Unlike graphite, DLCs usually present a typical short-range ordered amorphous phase, which is a mixture of sp3 type tetrahedral structure (diamond hybrid) and sp2 type trigonal structure ( Graphite hybrid), this feature reflects the material has excellent friction and mechanical properties such as low friction coefficient, flat wear rate, high hardness, and high elastic modulus. Another type of DLC coating, the so-called low-friction carbon coating (NFC), can reach the lowest coefficient of friction (0.005) among known materials. In the sliding resistance of the NFC-NFC friction pair, the NFC coating is No adhesion transfer film is formed on the part, but the passivation of the contact surface by hydrogenated carbon atoms results in an ultra-low friction coefficient.

(2) Transition metal disulfide (TMDs) lubricating materials

In the TMD family, MoS2 and WS2 are widely used for their reliable lubricating properties. The primary mechanism for achieving low shear resistance at the interface is parallel to sliding The direction-oriented base surface and the transfer film formed on the friction coupler.

MoS2 and WS2 coatings will not oxidize or react with water vapor in dry gas or ultra-high vacuum, thus maintaining their reliable internal lubrication. However, in humid air, friction oxides such as MoO3 and WO3 may be formed due to the dangling edges of the base surface or the reaction of unsaturated bonds with water vapor or oxygen in the environment. At this time, the sliding friction coefficient is relatively high (0.15-0.2), and the wear life is also concise.

(3) Polymer lubricating materials

Polymer dry lubricant is usually deposited on the surface of the substrate in the form of a coating (film) (such as polymer-based engine bearing caps). The molecular structure of these materials is composed of long chains parallel to each other, and the intermolecular bonding strength is weak. It may slip under stress.

PTFE is typical of this type of dry lubricant. Unlike other dry lubricants, PTFE does not have a layered structure, but it is easy to slide between PTFE macromolecules, similar to a layered structure. The minimum static and dynamic friction coefficient of PTFE can be reduced to 0.04. The metal treated with PTFE coating can be used under harsh conditions of temperature, pressure, and media, and can achieve an extended protection period.

（4）High temperature resistant dry lubricant

Some oxides, such as B2O3, MoO2, MoO3, ZnO, Re2O7, TiO2, V2O5, and PbO, have a low melting point and soften at high temperatures, and have better properties The anti-friction ability. PbO has better lubricating performance than MoS2 in the temperature range of 480℃～850℃. Many metal fluorides and their compounds have excellent lubricating properties at high temperatures, such as CaF2, BaF2, LiF, NaF, and CeF3, and LaF3 have excellent lubricating properties at 500-1000℃.

Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. If you are looking for dry lubricant, please contact us.