What is lubricating oil additives？

The concept of lubricating oil additives is to add one or several compounds in the lubricant to give the lubricant some new characteristics or improve some of the existing characteristics in the lubricant. Additives are divided into antioxidants, anti-wear agents, friction modifiers, extreme pressure additives, detergents, dispersants, foam inhibitors, anti-corrosion and rust inhibitors, flow point improvers, viscosity index improvers, etc. according to their functions. The additives sold in the market are generally composites of the above single additives. The difference is that the composition of the single additive is different and the ratio of several single additives in the composite additive is different.

GrapheneLubricant Oil Additive

Since graphene was invented and won the Nobel Prize in Physics, everyone has put great expectations on the benefits this new material will bring to mankind. In the past two years, global application research on graphene has become more frequent.

In 2016, after years of research and field testing of thousands of cars, graphene oil additive, the research and development result of polycarbon composites, was announced, which attracted widespread attention in the automotive aftermarket. On January 4, 2017, Polycarbon Composites held a global press conference for the product, which attracted a lot of industry leaders to observe.

The oil additive is added to the car engine oil. Through the oil circulation, it can reach each friction surface in the engine cylinder to enhance the machine's anti-wear ability. In addition, the product can also be firmly attached to the metal surface to repair wear grooves and scratches, forming a layer of "graphene protective film" to isolate direct friction between metals. It can keep the engine of a new car after a period of time as new; let the engine of an old car increase power, save energy and reduce consumption, it is simply another technological revolution in the application of graphene.

Through actual experience and scientific and technological testing, thousands of car owners have confirmed that after adding this graphene oil additive, their car has more power, less noise, no shaking of the steering wheel, and the problem of oil burning has been solved. Fuel consumption and car Exhaust emissions, etc. are significantly reduced.

Relevant experts said that the graphene lubricant additives of polycarbon composites overturned people's existing understanding of traditional automobile oil protective agents. While providing car owners with a good car experience and tangible benefits, it will reduce exhaust hazards and improve the current situation of urban smog, which has social significance beyond the product itself.

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 oil additives, please contact us.

Molybdenum disulfide as a lubricant

Like most mineral salts, MoS2 has a very high melting point but starts to sublime at a relatively low 450°C. This property is useful for purifying compounds. Due to its layered structure, the hexagonal MoS2 is like graphite and is an excellent dry lubricant. It and its cousin tungsten disulfide can be used as a surface coating in mechanical parts (for example, the aerospace industry), two-stroke engines (the type used in motorcycles), and barrels (to reduce friction between bullets and ammunition) ).

Unlike graphite, the lubricating properties of MoS2 do not depend on adsorbed water or other vapors. Its maximum temperature in an oxidizing environment is 350°C, and its maximum temperature in a non-oxidizing environment is 1100°C. Its stability allows it to be used in high-temperature applications where grease is not practical.

It is understood that molybdenum disulfide powder is recognized as the best solid lubricant in the world, but in the application of lubricating oil, because molybdenum is only soluble in aqua regia and boiling concentrated sulfuric acid, and the physical diameter of molybdenum particles is large, it will form in the oil Sediment layering can not be uniformly integrated with the engine oil, so it can only be added to the grease. This makes the manufacture of molybdenum disulfide lubricants a global problem. At present, only a few companies in Germany and the United States have mastered this technology.

Molybdenum disulfide is the main component of molybdenite—solid black powder with a metallic luster. The chemical formula is MoS2, the melting point is 1185°C, the density is 4.80g/cm (14°C), and the Mohs hardness is 1.0-1.5.

Analysis of the advantages and disadvantages of molybdenum disulfide as a lubricant

(1) Thoroughly prevent oil leakage, clean and clean, which significantly promotes civilized production.

(2) A large amount of grease can be saved.

(3) Improve the technical operating conditions, extend the maintenance cycle, reduce the labor intensity of maintenance workers, and save labor.

(4) Due to the low friction coefficient of molybdenum disulfide, the frictional resistance between the friction devices is small, which can save electricity. According to the measurement of the brother unit, the power can be held by 12%.

(5) It can reduce mechanical wear, extend the service life of friction equipment, reduce the loss of equipment parts, and improve the attendance rate of the equipment.

(6) The application of molybdenum disulfide lubrication solves critical technology and improves work efficiency and accuracy.

(7) Molybdenum disulfide has the functions of filling and filling, which can restore the geometric dimensions of individual parts and extend the service life.

(8) Molybdenum disulfide has the characteristics of moisture-proof, waterproof, alkali-proof, and acid-proof.

(9) The use of molybdenum disulfide plastic or powder smelted molded parts can save many non-ferrous metals.

(10) After using molybdenum disulfide lubrication in some equipment, the complicated oil supply system can be omitted, which significantly simplifies the structure of the equipment, relatively improves the effective area utilization, and will also cause significant reforms.

(11) Molybdenum disulfide also has shortcomings, such as poor thermal conductivity, low friction coefficient, and low permeability (compared to thin oil). These shortcomings are the main obstacles to expand the scope of use further. On the contrary, industrialized countries attach great importance to the research of solid lubricants and have also held international lubrication conferences to exchange relevant information and discuss new technologies.

Molybdenum disulfide as a superconductor

In addition to its lubricity, MoS2 is also a semiconductor. It is also known that when doped with an electrostatic field, it and other semiconductor transition metal chalcogenides become superconductors on its surface.

Until 2018, the mechanism of superconductivity was uncertain when Andrea C.Ferrari of the University of Cambridge (UK) and his colleagues and the Turin Polytechnic Institute (Italy), reported on Duogufei. The surface of the meter is related to the superconducting state in MoS2. The author believes that this Fermi surface topology will serve as a guide for seeking new superconductors.

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 MoS2, please contact us.

As long as you have bought motor oil, you will know that motor oil is generally composed of two parts, one is base oil and the other is engine oil additive. What kind of relationship do they have? How do they affect the quality of engine oil? In daily life, we often hear the classification of engine oils: mineral engine oil, semi-synthetic engine oil and fully synthetic engine oil. This classification method is based on the processing technology of the base oil used in the engine oil. In fact, engine oil About 80% is base oil, and about 20% is engine oil additive.

Relative to the types of base oils, you may be unfamiliar with oil additives in lubricants. Although base oils are very important, you should know that good lubricants are not good base oils that can bring 100% superior performance. Engine lubricating oil not only plays a role in lubrication, but also needs to bring cleaning, sealing, and anti-rust effects to the engine. No matter how good the base oil is, it cannot perform all functions in every aspect.

First, let us briefly understand the common engine oil additives:

Detergent

When the engine is operated at high temperature, the phenomenon of paint film (Vanish) and carbon deposit (Carbon) will be produced, which must be removed by the detergent in the engine oil, and its composition is metal salts.

Dispersant

When the engine is operating at low temperature, if it is not driven at high speed for a long time, so-called sludge will be produced. To prevent it from being generated, a dispersant must be added to the oil to evenly disperse the sludge in the oil to prevent the sludge from being deposited in the oil filter. On the valve push rod and piston ring, the lubricating oil path is not smooth and the unlubricated parts are chipped and worn.

Anti-Oxidant

Under the high temperature of the engine, the engine oil is especially easy to cause oxidation reaction with the air. After the engine oil is oxidized, the color will deepen and the viscosity will increase, thus increasing the load on the engine. At the same time, the organic acid generated after oxidation will also corrode the engine parts, so the oil is maintained. Oxidation stability is very important, especially in extremely high temperature turbo engines.

Anti-Rust Additive

In order to prevent the metal parts of the engine from rusting, it is of course necessary to add rust inhibitors. The ingredients of this additive contain a polar radical (Polar Radical), which uses the intermolecular polarity to adsorb on the metal surface to protect the metal from air and moisture. And rust due to salt erosion.

Anti-Corrosion Additive

Same as anti-rust additives, but the former is used to protect ferrous metal (Ferrous Metal) parts and the latter is used to protect non-ferrous metal (Non-Ferrous Metal) and alloy (Alloy) parts from corrosion by sulfur and organic acids .

Viscosity Index Improver

The base oil is limited by the nature of crude oil. Its viscosity index can only be improved to a certain extent by the processing technology, and then it must rely on the viscosity index improver. It is also because of the invention of the viscosity index improver that the oil with multiple viscosity can be produced.

Pour Point Depressnat

Pour point depressant is also called pour point depressant. The so-called pour point is to measure the temperature of a certain oil when it starts to not flow, plus 3℃ is the pour point. There will be more or less wax in the oil. (Although the wax has been removed during the refining of the base oil, it still cannot reach 100%). Once these waxes become crystals and solidify at low temperatures, they will prevent the oil from flowing. In order to make the engine start smoothly in winter, it must Inhibitors are added to reduce the pour point, prevent wax from crystallizing, and adapt to cold weather.

Anti-Wear Additive

The so-called boundary lubrication (Boundary Lubrication) occurs when the engine is under high temperature and high pressure, that is, under the condition of high thermal expansion of the metal active surface, the oil film is squeezed apart, and direct friction between metal and metal is formed. In order to prevent In this case, it is necessary to add anti-wear additives. When the additives come into contact with metals, they chemically react, and a protective film is produced to protect the metals from wear when they are in contact with each other.

Anti-Foaming Agent

When the oil is repeatedly stirred in the engine, foam will naturally occur. Where there is foam, where there is no oil film, the engine will lose its protection. On the other hand, where there is foam, it also means that the contact surface with the air increases. It also accelerates its oxidation, so it is necessary to add a defoamer to avoid foam.

Dye

Function 1: For identification, for example, the automatic transmission fluid (ATF: Automatic Transmission Fluid) of automobiles is dyed red to facilitate identification and maintenance in case of oil leakage;

Function 2: For marketing and advertising, for example, most of the two-stroke engine oils in Japan are dyed light blue or red. In addition to being beautiful, it can be used to advertise that the base oil in the lubricant is highly refined and light in color before it is dyed.

What is the formula ratio of Engine oil additive?

In fact, the formulations of all lubricant additives are relatively the same, but slightly different. The formulation of an engine lubricating oil is obtained through many steps such as research, development, and testing, and it takes several years to obtain. For example, some lubricants are specially formulated for urban congestion and often need to be started and stopped. Our fully synthetic extreme protection pays more attention to comprehensiveness and is more suitable for high-temperature engines with turbochargers.

If I use mineral engine oil, should I add a little engine oil additive, such as adding some detergent or anti-rust additive to achieve the effect of fully synthetic engine oil, isn't it more cost-effective?

This is not the case. What is the difference between mineral engine oil and fully synthetic engine oil in base oil? We do not recommend that you buy the engine oil additive by yourself, because the finished engine oil is sold to consumers after strict bench testing and meets the industry specifications and the specifications of major car manufacturers. The formula is the most optimized formula. Add engine oil by yourself On the contrary, additive will affect the efficacy of Castrol oil, and there is a risk of destroying the original efficacy.

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.

Thickness of oil film

When it comes to lubrication, what do you think of? It should first produce a thick film to separate the base oil on the two metal surfaces, because the role of lubricating oil is to avoid surface contact between metals. Therefore, under this demand, the oil must be able to provide the ability to separate the friction surface, which requires three supporting factors-relative speed, base oil viscosity and load. These three factors are also affected by temperature, pollution and other factors. When the oil film thickness balances these factors, that is, a viscous fluid film is generated by the relative speed to completely separate the two friction surfaces, and the pressure generated by the fluid film balances the external load, it is called hydrodynamic lubrication.

In applications with rolling contact (negligible relative sliding motion), even with a large local pressure point, it may affect the thickness of the oil film between the metal surfaces. In fact, these pressure points also play an important role. The relationship between the pressure and viscosity of the base oil allows the viscosity of the oil to temporarily increase due to higher pressure. This is called elastohydrodynamic lubrication. Although the oil film will be very thin, it can still produce a complete oil film separation.

In practice, the ideal state of the machine surface is to achieve complete separation, and the thickness of the film is to provide the best protection for reducing friction and wear. But if there are no conditions to meet these oil film thicknesses, such as when the relative flow rate is insufficient, the viscosity is insufficient, or the load is too large, what will happen? In fact, the design and operating parameters of most machines allow insufficient speed, such as when starting, stopping or changing direction. When the temperature is too high, the viscosity will decrease, and excessive pollution will also cause the abrasive particles in the oil film gap to contact.

When the prerequisites for hydrodynamic or elastohydrodynamic lubrication are not met, the base oil will seek support under the so-called boundary contact conditions. This support factor requires the search for additives with friction and wear control properties. Therefore, the base oil and additives are blended together to produce lubricating grease products that meet specific needs, thereby reducing the expected boundary lubrication, and the lubricant has oil film strength and boundary lubrication properties.

The role of oil film

The strength of the oil film is an important factor in addition to the thickness of the oil film to reduce friction and control wear. As mentioned above, in fluid dynamics and elastohydrodynamic lubrication, viscosity is the key to the thickness of the oil film. When the base oil viscosity is not enough to overcome the surface friction between metals, the base oil and additives are required to produce a chemical synergistic effect to form a surface protection mechanism. Under these boundary conditions, boundary lubrication will also be affected by the chemical and physical properties of the mechanical surface and any other environmental factors, so even when the load is heavy, the temperature is high, or the relative surface velocity is low, the oil film strength will be improved. .

Non-lubricated surface interaction

If you observe the mechanical contact surfaces at the molecular level under a microscope, you will find that even though they are processed very smoothly, they are actually relatively rough. This is like an astronaut looking at the earth from a distant space perspective, the earth is a perfectly smooth sphere, while people standing on the surface of the earth see the earth as full of high and low mountains and valleys.

This is because when two metal surfaces are in contact, the actual contact area will be significantly lower than the apparent contact area. From the "microscopic mountain" under the microscope, these contact surfaces are the highest points of unevenness, and the contact rate of low rough surfaces is low. These rough surfaces will undergo elastic deformation due to the corresponding shear strength of the metal. Therefore, the initial contact point first produces elastic deformation, and then more contact points will be connected, and the actual contact area will increase as the load intensity increases.

What is friction?

Friction is the process in which the sliding motion of the interacting surface is subjected to several influencing parameters to produce resistance. Most people think that surface roughness is the main factor in friction. However, when considering that the actual contact area may be less than 1% of the apparent contact area, the actual roughness becomes less important. The cause of friction should be the result of adhesion at the molecular level of rough contact.

How does wear occur?

In the case of insufficient lubricating film thickness on the metal surface, rough contact points may cause cold welding, which is a prerequisite for adhesive wear. The adhesion on these rough points undergoes a hardening process of reinforcement, therefore, the shear point generally occurs at the level below the rough contact point where the metal is not strengthened. As metal shears, the rough tip is either transferred to another surface or broken down into an abrasive particle.

Adhesion is generally considered the initial form of mechanical wear. In addition to the wear of the abrasive grains, there are external sources of wear, causing the abrasive wear to become more destructive. This form of wear is called three-body wear. The two-body wear is caused by sharp surface contact points produced by cutting or planing.

Surface fatigue occurs during rolling contact. The fatigue mechanism comes from the formation of cracks on the working surface or inside the surface layer and growth. High stress under surface rolling conditions can cause fatigue wear.

How to control friction and wear?

The friction and wear control additive is mixed with a small amount of base oil, which has the polarity to promote the adsorption of the metal surface. Due to the interaction conditions, these adsorption forces chemically react with the surface, which is inversely proportional to the conditions that produce sufficient oil film thickness: higher pressure and higher temperature.

When the surface of the machine interacts with higher pressure and temperature, the additive reduces the impact of metal-to-metal contact (wear) by creating a more ductile initial molecular layer on the machine surface. These friction control layers directly reduce the contact process The shear strength becomes a "victim". The initial layer can release the force of the weaker molecular bond of the lubricant and the rough boundary conditions between the metal and the metal to produce a strong bond, thereby reducing friction. The formation of low-shear-strength films is also affected by the type of basic raw materials and mechanical surface metallurgy.

Three types of oil additives help reduce friction and control wear. They are friction modifier, anti-wear additives and EP additives.

(1) Friction Modifier

Polar compounds such as fatty acids added to the base oil, by forming a soap film, reduce friction at low sliding speeds. They are usually used for components that require fuel economy to reduce friction and stick-slip at low speeds, such as in engines or transmissions. They act as anti-wear additives, but are more effective than anti-wear additives at light loads and do not require high temperature conditions. However, when the metal surface reacts more strongly to fatty acids to produce metal soap, the decomposition temperature will be higher.

(2) Anti-wear additives

These polar compounds are usually based on sulfur or phosphorus, such as zinc dialkyldithiophosphate (zinc alkyl dithiophosphate, ZDDP oil additive) type additives, which are developed to chemically react with the metal surface only under boundary conditions. Anti-wear additives are more effective at higher temperatures, where they become more active and produce barrier films. ZDDP oil additive has been widely used for wear protection and can also be used as an antioxidant in oil.

(3) EP Additives (anti-wear additives)

When the surface temperature is too high, the function of friction modifier and even EP additives begins to weaken. EP additives are also based on sulfur and phosphorus, and are the best choice under high temperature conditions. These additives can form soap-like films with low shear strength to react with metal surfaces and can withstand relatively high temperatures. Although this reaction is conducive to the formation of oil film, it may also lead to more chemical corrosion of reactive metals, so be careful.

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.

As a new type of dry lubricant, tungsten disulfide WS2 has relatively stable chemical properties and can adapt to too harsh conditions. WS2 can provide maximum protection against wear, rust, and corrosion, and is environmentally friendly. It is non-toxic and will not harm human health or cause pollution to the environment. It can be widely used in the automotive industry to provide Brings many benefits.

WS2 is a layered crystal structure with excellent lubricity and a very 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, seizure, etc., eliminate or reduce Equipment repair and maintenance problems caused by friction, wear, etc., improve the working efficiency and service life of auto parts, and save time and cost for users. 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 friction coefficient of WS2, the lubrication effect can be maintained for parts used for high temperatures 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 piston ring is the least durable part of the engine. The piston ring rotates with the piston at high speed and is affected by the high temperature and high-pressure gas in the cylinder. The oil is particularly prone to deterioration at high temperatures, so its wear is severe. With tungsten disulfide coating or tungsten disulfide grease, friction is reduced, and it can move happily with the piston under the conditions of high speed, high pressure, high temperature, and extremely difficult lubrication.

The crankshaft is an essential part of the engine. Its working condition is also high-speed rotation, so it must be able to withstand wear and fatigue. The surface of the journal is generally high-frequency quenched or nitrided. The body is coated with WS2 and finely ground, and 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. The infrequent operation, the lubricating oil used, will deteriorate and lose its lubricating effect. WS2 has excellent mechanical stability and thermal stability, which can guarantee the lubrication effect of these parts and reduce wear.

WS2 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, to protect against rust and corrosion.

The excellent performance of WS2 is not only used in the automotive industry, but also a wide range of applications, such as the machinery industry, plastics industry, medical device industry, military, aerospace, satellites, aerospace ships, and other high-tech fields.

Other application areas of WS2 nanoparticles

（1） WS2 nanoparticles can be used as an additive for high-temperature grease. After adding tungsten disulfide powder, the fat has excellent properties such as high dropping point, high oil film strength, and low friction factor. It is also used as a colored and black brush additive in the carbon industry. It can also be applied to superhard materials and welding wire materials, as well as to solid lubrication in aerospace (-270℃～1300℃, only WS2 can withstand this temperature in space lubrication), aviation, military, and other fields;

（2）WS2 nanoparticles can replace the application fields of MoS2 and graphite, and have a broader range of uses. Moreover, molybdenum and tungsten are chemical elements of the same family, and tungsten is more massive than molybdenum and has more stable chemical properties;

（3）WS2 nanoparticles are used as a solid additive for lubricating grease. The powder is mixed with lubricating grease at a ratio of 1% to 5%, which can enhance the lubricating performance and high temperature and extreme pressure performance of lubricating grease. In use, ws2 powder is adsorbed on the surface of matching moving parts, which can effectively reduce friction, improve lubricity, drop point and heavy load performance for a long time;

（4） WS2 nanoparticles as a lubricating coating. WS2 powder can be sprayed on the surface of the substrate by dry and cold air under 0.8Mpa (120psi) pressure. Spraying can be carried out at room temperature, and the coating is 0.5 microns thick. In another way, the powder is mixed with isopropanol, and the sticky substance is applied to the substrate. At present, WS2 coating has been used to many fields, such as automobile parts, racing engine parts, aviation parts, bearings, shafts, deep-sea transportation tools, cutting tools, blades, cutters, knives,  high-precision bearings, valve components, Pistons, chains, etc.

Two established ways the tungsten disulfide powder can be used are:
（1） Mixing the tungsten disulfide powder with wet lubricants (such as oil, grease or other synthetic lubricants):
The tungsten disulfide powder can be mixed 1wt% to 15wt% (as required) with grease or oil. This will enhance lubricity of the mixture and also improves High Temperature and Extreme Pressure properties of mixture. During the use, tungsten disulfide powder in the mixture will get coated on mating/moving parts, which in turn reduces friction and improves lubricity and load bearing ability for much longer cycles.

（2）Coating the tungsten disulfide powder on a substrate requiring (dry) lubricant
The tungsten disulfide powder can be coated by spraying (at 120 psi) the substrate with dry (& or cool) pneumatic air. It does not require any binders and spraying can be done at normal room temperature. Coated film will be 0.5 micron thick. In an alternative application method, the powder can also be mixed with isopropyl alcohol and this paste could be buffed to the substrate.

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 WS2,please contact us.

Lubricating oil base oil possesses the basic characteristics of lubricating oil and certain use properties, but only relying on improving the processing technology of lubricating oil cannot produce lubricating oil with various properties that meet the requirements of use. In order to make up for the defects in the properties of lubricating oil and to give the lubricating oil some new excellent properties, various additives with different functions must be added to the lubricating oil, and the addition amount ranges from a few percent to tens of percent.

Molybdenum disulfide is one of the few natural high-quality solid lubricants with a friction coefficient of only 0.05, which is smaller than some other lubricants. Aerospace solid lubricants use specially processed nano-IF-MOS2 (inorganic fullerene structure molybdenum disulfide nanoparticles), which is a non-polar spherical structure composed of 60 molybdenum disulfide molecules, similar to carbon 60 in space The particle size is 40 nanometers, and its extreme pressure and anti-wear ability is twice that of ordinary MoS2!

MoS2 has natural weak alkalinity and excellent antioxidant capacity, which can extend the mileage of engine oil. The regular flow of engine oil can maintain the continuous effect of the MoS2 suspension and reduce the precipitation of molybdenum. The biggest problem with MoS2 suspension is that the particles are non-lipophilic substances, and the particles will precipitate if they are not used for a long time.

The problem of sedimentation of particle suspensions is one of the problems that have not been completely solved in the world today. There are many technologies that claim to solve suspension sedimentation, but there are no relevant patent documents to check.

In order to overcome the suspension problem of MoS2, the second generation of molybdenum lubricant additives-organic molybdenum appeared.

Organic molybdenum is a liquid soluble in engine oil. When the engine is running at high temperature and extreme pressure, it will decompose MoS2 and form a MoS2 film on the cylinder wall to achieve the anti-wear and anti-friction lubrication effect and solve the problem of MoS2 suspension.

But organic molybdenum is easy to oxidize and decompose to produce acidic substances, which will cause the engine oil to deteriorate early, and its chemical properties are not stable. Among them, the useful content of MoS2 is relatively low, and the effect lasts for a short time, so it needs to be supplemented frequently.

Another problem is that ester-based fully synthetic engine oils are very oily and can quickly precipitate various nano-scale suspended particles, including MoS2 suspended particles, and quickly destroy and remove the MoS2 film structure on the friction interface. In the test, it was found that the mixed ester fully synthetic motor oil will quickly sink various suspended particles to the bottom. Therefore, the long-term performance of ester fully synthetic motor oil includes the ability to quickly precipitate particles.

There will be a phenomenon where ester fully synthetic engine oil and solid lubricant compete for the friction interface. It is a fully synthetic ester motor oil, no matter what molybdenum product is used, this is also the functional conflict of the representative products of the two lubrication theories.

Therefore, the choice of MoS2 products should be based on the engine oil used in the car, as well as the focus, not just adding a certain lubricating additive.

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 MoS2 or organic molybdenum, please contact us.

Friction is a natural phenomenon that exists in the natural world. It is indispensable in people's daily production and life, but at the same time, it also brings unavoidable and unavoidable losses and harms. Friction not only consumes energy but also causes a lot of waste of resources. According to statistics, about one-third of the world's energy is consumed in resistance in various forms, and about 80% of machine parts fail early due to wear and tear.

Friction and wear mainly occur on the surface of friction parts. Adding nano oil additive to automotive lubricants is one of the important methods to reduce surface friction and wear. In recent years, the application of advanced carbon materials in the field of friction has received great attention. Especially with the discovery of rare earth graphite, the research on the application of carbon materials in tribology has entered a new upsurge.

1. What is graphene

Graphene is a new two-dimensional planar carbon material with atomic thickness. In a single-layer graphene crystal, carbon atoms participate in hybridization in the form of sp2, are connected by C-C covalent bonds, and are closely arranged into a two-dimensional honeycomb lattice structure with a six-membered ring the same as the carbon plane in three-dimensional graphite. The theory The thickness is 0.335nm, and the carbon six-membered ring periodic structure can be infinitely expanded in the same plane. It is a nanocrystalline material with macroscopic dimensions. The properties of graphene are closely related to the number of carbon layers. When the number of carbon atom layers of graphite flakes is less than 10, these graphite flakes exhibit different electronic characteristics from ordinary three-dimensional graphite crystals; and when the number of carbon layers exceeds ten layers at most, In addition, the properties of graphene are also closely related to the integrity of its crystal structure.

2 Graphene Lubricant

The friction between graphene layers is affected by various aspects such as stacking form, relative sliding direction, size, defects, layer spacing, and the number of layers. Studies have shown that graphene stacked in the form of incommensurate (lattice mismatch) sliding friction force along the path connecting incommensurate states will be smaller. It is found through an accurate calculation that the friction between graphene layers increases as the distance between the layers decreases. When the graphene layers are stacked in the form of AB, the friction will become more apparent as the distance between the layers increases. Besides, the shape, size, and introduction of the ink can cause frictional changes between graphene layers. The study found that as the number of graphene layers decreases, the friction and sliding friction between graphene layers gradually decreases. When the number of graphene layers reaches 2-3, the viscosity of the graphene layer disappears, and the average friction force is almost zero. Therefore, as a lubricant additive, compared with single-layer graphene, stacked multi-layer graphene is more conducive to the improvement of lubricating performance.

3 Application of graphene in industrial lubricants

Graphene is used as a modifier in industrial lubricants, and it should have good compatibility with base oils to ensure that it can form a uniform and stable dispersion system in industrial lubricants. The surface of graphene oxide contains a large amount of oxygen-containing functional groups, which makes it have excellent hydrophilic properties, so it is difficult to disperse in oil-soluble basic industrial lubricants, and it is prone to agglomeration. In addition, intact graphene has high chemical stability, weak interaction with other media, and great van der Waals gravitational force between layers. It is also difficult to stably disperse in base oils.  In order to effectively exert the lubricating properties of graphene lubricant additive, physical adsorption and chemical modification are mainly used to improve the uniform dispersibility of graphene in industrial lubricants, and uniform and stable graphene are configured with lubricating oil. Compared with the natural graphite sheet, the modification of graphene has a small volume and a thin layer structure, and it is easy to enter the friction contact surface, forming a continuous physical adsorption friction film, preventing direct contact with the surface of the friction pair, thereby modifying the graphene to expand the lubricating oil. It has a lower and more stable friction coefficient, and higher bearing wears resistance.

4 Conclusion

Graphene has shown application value in the field of high-performance lubricants due to its ultra-thin nano-sheet structure, excellent thermal conductivity, self-lubricating properties, mechanical properties, and good chemical stability. As a lubricant additive, it is easy to enter the friction interface and form a stable physical isolation film, which prevents direct contact with the friction surface, thereby enhancing the bearing capacity and extreme pressure and wear resistance of the lubricant. However, due to the large specific surface of graphene, the strong interaction between the carbon layers, the poor interaction with the base oil, and the possibility of agglomeration, it is difficult to stably disperse in the lubricant for a long time, which brings great disadvantage to its application. To better promote the application of graphene in the field of lubricants, more in-depth research work is needed in the following areas:

(1) Study on the compatibility between graphene and base oil. In-depth research on the surface modification technology of graphene, combined with actual industrial production, to achieve low-cost controllable modification of graphene and long-term stable dispersion in industrial lubricants.

(2) Tribological mechanism of graphene in industrial lubricants. An in-depth understanding of the physical and chemical changes that occur on the surface of different friction material materials during the friction process of graphene as a lubricant additive provides a more effective surface modification for graphene.

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.

1. Overview of nanomaterials as oil additive

With the rapid development of science and technology in the 21st century, aerospace, high-speed rail, heavy machinery, and automobile industries have increasingly strict requirements on the service life and reliability of machinery. Mechanical equipment in high load and high speed, friction, and wear under high temperature and the extreme condition is relatively severe, urgent need high-performance lubricant oil. Therefore, prompting lubricant oil quality upgrading, development of excellent anti-wear performance lubricant oil is of significant value. The lubricant base oil in the oil quality is fundamental, oil additive quality and performance is the key to improve the quality of the world's major oil companies to develop new oil additive to improve the quality of the lubricant oil as a development focus.

 With the development of nanotechnology, scientific researchers have applied nanotechnology to the lubrication field. Nanomaterials are widely concerned as lubricant additives, which will give a massive boost to the development of high-performance and high-grade lubricating oil. Nanomaterials refer to the basic unit of materials in which at least one dimension of size is at the nanometer level, i.e., 1-100 nm range. They have the characteristics of small size, considerable surface energy, excellent anti-oxidation stability performance, and so on. Nanomaterials as lubricant additive, the most significant advantage is its tiny sizeable to enter the friction contact area, have good lubrication effect, in addition, the nanometer material has high temperature resistant nonvolatile or breakdown, not easy to react with other additives, satisfy the working condition of high load, high speed, high temperature and extreme inferior demanding conditions using, break through the traditional additives can limit the use of better protection of mechanical equipment.

2. Action mechanism and classification of nano material oil additive

The anti-wear and anti-friction mechanism of nanomaterials are different from that of traditional extreme pressure anti-wear additives. Conventional extreme pressure anti-wear additives contain active groups such as phosphorus, sulfur, and chlorine, which mainly rely on adsorption on friction surface or reaction with the metal surface to form chemical reaction film to achieve anti-wear and anti-friction effect. The action mechanism of nanomaterials mainly creates the following four types: rolling bearing effect, building a protective film, filling and repairing effect, and polishing effect. 

The rolling bearing fact is mainly that the ball, rod, and linear nanoparticles play a rolling and supporting role on the contact surface, changing the pure sliding friction into sliding and rolling resistance.The mechanism of forming protective film mainly depends on the deposition or adsorption of nanoparticles on the friction contact surface during the relative sliding process of the friction surface, and then the formation of physical protective film or interaction with the friction surface to form a chemical protective film to reduce the contact between the friction surface. When the contact surface is damaged, the friction surface will show scratches, ravines, or pits, and the surface roughness will increase. Nanoparticles will be deposited in the surface depression, and the friction contact surface will be leveled to reduce the severity, to achieve the anti-friction effect. The polishing effect mainly reduces the roughness by reducing the micro-convex body of the friction surface through the hard nanoparticles. When a nanometer material is used as a lubricant additive, in addition to the action of the nanometer material itself, the relationship between the nanometer material and the oil film should also be considered. Therefore, the lubrication mechanism should be considered comprehensively.

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.