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.

There are many kinds of engine oil additives used in internal combustion engines, and the functions of different additives are also different, divided explicitly into metal detergents, ash-free dispersants, and anti-oxidation and anti-corrosion agents. Besides, with the gradual enhancement of environmental protection awareness in China, the requirements on the quality of lubricating oil are more and more strict, so the development of additives in demand and varieties is more rapid.

1 Metal cleaner

In the engine oil of the internal combustion engine, the metal cleaner is undoubtedly an essential additive among them, and its components include sulfonate, alkyl phenol salt, alkyl salicylate, and other carboxylates.With the rapid development of internal combustion engine oil, it is urgent to develop a lubricating oil metal cleaner with excellent thermal stability, low viscosity, and low turbidity to further improve fuel economy, extend the oil change period and enhance its environmental protection capability.

2.No ash dispersant

For non-ash dispersing agents, it mainly plays a role in dispersing and solubilizing the carbon deposition, sludge, and acidic oxidation products in the oil. With the improvement of lubricating oil production technology, polymer ash-free dispersant has been applied and developed. Polymer ash-free dispersing agent, in addition to having excellent low temperature dispersing, but also can significantly improve the product's thermal stability and high-temperature cleanness, has a wide range of applications in the field of high-grade internal combustion engine oil. At present, polymerization, chlorination - free, and multifunction have become the main development direction of ash-free dispersants.

3.Anti - oxygen anti-corrosion agent

In the process of oil oxidation, a large number of oxides, alcohols, acids, esters, hydroxy acids, and other products will be generated during this period, and the generated compounds will further react, resulting in the formation of insoluble macromolecular compounds with oil, which will lead to the decline of oil quality and lead to the increase of oil consumption. At the same time, when the oxidation of compounds attached to the piston ring, it will lead to the formation of carbon deposition in the oil, resulting in increased viscosity. Besides, organic acids will also be generated in the process of oil oxidation, which will cause a certain degree of corrosion to steel sleeve, bearing and other metals, and affect their service life. Therefore, anti-oxidation additives should be added into the lubricating oil to delay the oxidation rate of lubricating oil further and prolong the oil change period. At present, the high-grade lubricating oil has strict requirements on viscosity, sediment, and other aspects, improve the performance of antioxidant conditions.

4.Friction modifier

Friction modifier refers to a kind of material which forms a physical adsorption film or a chemical adsorption film on the friction surface to reduce the friction factor, thus enhancing the lubrication of the friction surface and improving the capability of the oil film. Among them, adding friction improver in lubricating oil can improve the lubrication of friction pair, reduce the friction loss of mechanical parts, and help to extend the service life of mechanical parts.

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.

Friction is universal. Statistics show that friction consumes one-third of the world's primary energy, and 80 percent of machine parts fail because of wear and tear. According to statistics, the annual loss caused by friction and wear in the United States, Britain, Germany, and other industrial developed countries account for about 2% to 7% of their gross national product (GDP). According to the GDP of the United States, the annual loss caused by friction and wear is estimated to be up to 150 billion us dollars. Reducing friction reduces energy consumption, which not only reduces the impact on oil resources but also means reducing CO2 emissions, which reduces the pressure on the environment and public health.

The importance of studying tribology

The study of friction, wear, and lubrication involves many fields such as materials, chemistry, mechanics, physics, and mechanics. These studies are of great significance for improving the reliability of mechanical equipment, improving work efficiency and product quality, and developing high technology and lubrication protection materials and technologies used in the field of national security. Tribology in the national economy and social development of the strategic position and important role, not only reflected in energy saving, consumption reduction and emission reduction, solve the problem of tribology, but also can significantly improve the reliability of mechanical systems in the field of aerospace, reduce and prevent the occurrence of major catastrophic accidents. Tribology is a vital force for the country to save resources and energy, protect the ecological environment, and realize the coordinated development of industrial society, natural ecology, and environmental resources.

Wear is due to mechanical action, sometimes accompanied by chemical reaction (refers to corrosion wear) and electrical activity (Edm wear), the material surface in the relative motion of the constant loss of the phenomenon, is accompanied by friction and the inevitable result, there is friction is wear. To reduce the consumption of materials and energy and extend the service life of parts, it is necessary to reduce friction and wear. Many antifriction and wear-resistant coatings have been successfully prepared by electroplating, electroless plating, and composite plating.

The fundamental cause of wear is the result of mechanical, physical, and chemical interaction between the object subjected to tribological load and the relevant elements in the friction pair system. What kind of communication occurs depends on the nature of all the aspects involved in the wear process, such as the type of motion, the motion process, the average load, the speed, the temperature, the surface characteristics, and the duration of the amount.

Classification of wear

There are many classification methods of wear, mainly including the following three classification methods, namely, according to the environment and medium of wear; According to the wear surface contact property and wear mechanism classification; Classification by wear mechanism is described below:

1) Fatigue wear

Some machine parts such as cams, gears, and rolling bearings, in rolling or rolling and sliding under the action of a joint cause of surface fatigue, a peeling phenomenon called fatigue wear.

2) Abrasive wear

When the surface of a material is in contact with a hard rough or bump, the event that causes the surface of the material to suffer loss is called abrasive wear.

3) Corrosion and wear

The wear and tear that work together are called corrosion wear.

4) Erosion and wear

Wear caused by solid particles or fluids striking the surface of a material at a certain speed, and Angle is called erosion wear.

5) Fretting wear

The wear between two contact surfaces caused by a small amplitude of relative vibration is called fretting wear.

To solve the problem of friction, the first choice at present is to add lubricating oil to reduce the friction coefficient and reduce the friction.

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 solid lubricant?

Solid lubricant is a kind of material that reduces the friction coefficient and wear by preventing direct contact of friction parts under regular use or high load. In exceptional cases where liquid lubricants such as oil and grease cannot be used, solid lubricants have an excellent application market. Besides, the solid lubricant is also an additive material for high-performance anti-bite and anti-wear coatings. It is often mixed with grease and lubricating oil in the form of powder particles to play a sliding role. This kind of special solid lubricant will slip when the friction pair slides relatively Fill out rough surfaces. Therefore, under extreme operating conditions, solid lubricant provides sufficient boundary lubrication conditions, thereby reducing the friction coefficient and reducing wear. Generally speaking, solid lubricants have a higher advantage than liquid oils under high vacuum conditions below 10^-2 Pa and near atmospheric pressure above 10⁴ Pa, and low temperatures below 0℃and high temperatures above 177℃.

There are five main types of solid lubricants: carbon-based materials, transition metal disulfides (such as MoS2 and WS2), polymers (such as PTFE lubricant), soft metal, and ceramic high-temperature lubricating materials. Among them, carbon-based materials and transition metal disulfides belong to the typical layered structure solid lubricant.

(1) Carbon-based lubricating material

Graphite is a typical carbon-based lubricating material with high-temperature resistance and corrosion resistance and is known for its reliable lubrication characteristics. Graphite has a layered solid with a hexagonal lattice. The atoms in the carbon base plane are bonded together by strong covalent bonds, while the base planes are combined by weak Van der Waals forces, resulting in a broken mechanical relationship between the aircraft. The presence of water vapor and oxygen in the environment can promote the shear movement between graphite crystal layers. When the base surface is worn, these active edges are neutralized (passivated) by adsorbing water or other vapors. Graphite can also maintain low friction. This is true for other carbon-based solid lubricants. Carbon-based lubricants also include various types of DLC coatings and low-friction carbon coatings (NFC).

2) Transition metal group disulfide (TMD) lubricating materials

In the TMD family, MoS2 and WS2 are widely used for their reliable lubrication performance. The primary mechanism for achieving low shear resistance at the interface is a base surface oriented parallel to the sliding direction and a transfer film formed on the friction couple. MoS2 and WS2 coatings do not oxidize or react with water vapor in a dry gas or ultra-high vacuum, thereby maintaining their reliable internal lubrication. However, in humid air, friction oxides such as MoO3 and WO3 may be formed due to the dangling or unsaturated bonds on the edge of the base surface reacting 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) PTFE lubricant:

Polymer solid lubricant is usually deposited in the form of a coating (film) on the surface of a substrate (such as polymer-based engine bearing cover). The molecular structure of these materials consists of long chains parallel to each other, and the bond strength between molecules Weak may slip under low shear stress. PTFE is typical of such solid lubricants. Unlike other solid lubricant, PTFE does not have a layered structure, but PTFE macro molecules easily slide, similar to a layered structure. The minimum static and dynamic coefficient of friction of PTFE can be reduced to 0.04. The PTFE-coated metal can be used under harsh temperature, pressure, and medium, and can achieve an extended protection period. Polymer-based nano composites, such as PTFE / nano Al2O3, also show excellent friction performance under specified test conditions.

(4) Soft metal lubricating materials

Due to low shear strength and high plasticity, some soft metals also have lubricating properties such as lead, tin, bismuth, indium, zinc, cadmium, and precious metals such as gold and silver. For example, Zn and Sn have been used in sliding bearings, while precious metals such as gold and silver have begun in the aerospace industry. In daily life, soft metals are widely used as solid lubricants in engine bearing materials.

Soft metals used as solid lubricant materials usually have a face-centered cubic lattice, so their crystals are all isotropic. Therefore, these soft metals do not have a high bearing capacity, and the external load can only be borne by the substrate. Another advantage of face-centered cubic crystals is that there is no low-temperature brittleness, and the lubricating properties will not be lost in low-temperature environments.

(5) High temperature resistant lubricating materials

Certain oxides, such as B2O3, MoO2, MoO3, ZnO, Re2O7, TiO2, V2O5, and PbO, etc., have lower melting points, soften at high temperatures, and have better properties. 

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.

MoS2 is a material found in the extraction of granite veins and is highly refined to a purity that can be used as a lubricant. MoS2 has a Mohs hardness of 1.0 to 1.5 and a density of 4.80 g/cm3. It starts to oxidize when heated to 315℃ in the air. The temperature increases, the oxidation reaction accelerates, and it is insoluble in water.
MoS2 as a solid lubricant has the advantages of low friction coefficient, high bearing capacity, full use temperature range, excellent adhesion, anti-friction, and corrosion resistance, but the moisture in the humid environment will cause the MoS2 friction coefficient to increase.

1.Preparation technology of MoS2 coating
 Surface engineering can be divided into two categories: surface modification technology (no cover) and coating technology (protection). With the development of surface engineering technology, the preparation of MoS2 coating has developed supersonic flame spraying technology, non-equilibrium magnetron sputtering, plasma-enhanced chemical vapor deposition, and laser melting based on single techniques such as electroplating, thermal spraying, and vapor deposition. Coating and other new composite preparation processes. However, the conventional MoS2 coating preparation technology is mainly vaporing deposition. Still, due to the high temperature and difficult to handle gases in the CVD process, PVD technology is by far the most commonly used coating preparation method.

2.Molybdenum disulfide coating performance study
The friction properties of molybdenum disulfide coating are related to many factors. First, the coefficient of friction is related to the hardness of the substrate and the surface roughness of the parts. Molybdenum disulfide coating exerts a lubricating effect through the substrate to bear the load. Generally, the higher the hardness of the substrate, the smaller the coating friction coefficient, and the better the abrasion resistance. The surface roughness of the parts directly affects the formation of the transfer film. The smaller the surface roughness, the lower the chance of mechanical fit of the lubricating coating thereon, and the lower the adhesive strength. Secondly, it is related to the basic physical properties of molybdenum disulfide coating. The particle size of the sheet, the crystal orientation parallel to the base surface, and the coating density and impurities will directly affect the lubricating performance. The most important thing is that MoS2 coating has the most significant impact on environmental conditions. Most MoS2 coatings have defects such as high wear rates under high temperature and high-pressure environments and performance degradation under high temperature and humid climates. Tribochemical reactions are natural to occur on friction surfaces in the atmospheric environment, resulting in oxide particles. Leading to accelerated wear, the existence of these factors makes the practical application of MoS2 coating is minimal.

3.MoS2 coating lubrication mechanism
Although the mechanism of MoS2 as a lubricating material has been studied for a long time, the theory explaining the excellent friction properties of MoS2 coating has not been unified.
One of the accepted theories is the theory of intracrystalline displacement. The lone pair of electrons in the lower S atoms of MoS2 penetrates the hole region composed of three S atoms in the upper layer and is negatively charged. Due to electrostatic repulsion, it is easy to be separated to obtain better lubrication.

The second MoS2 friction mechanism believes that low friction is due to the adsorption of some foreign substances on the surface of MoS2, which weakens the structure of MoS2. According to this theory, the friction coefficient of MoS2 should be increased in a high vacuum environment. At that time, tests confirmed the adsorption layer. It does affect the friction performance, but it just causes an increase in the friction coefficient.
The third is that the high-energy edge surface of the MoS2 crystal reacts rapidly with oxygen during the friction process to form a stable oxide. This has a weak attraction to the cleavage surface with low surface energy and other edge surfaces, leading to intergranularity: weak adsorption and low friction.

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.

What is PTFE?

Poly tetrafluoroethylene, abbreviated as PTFE, Teflon, it is a polymer compound formed by the polymerization of tetrafluoroethylene. Its simple structure is-[-CF2-CF2-] n-, which has excellent chemical stability and corrosion resistance. It is one of the best materials with corrosion resistance in the world today. Except for molten alkali metal, chlorine trifluoride, chlorine pentafluoride, and liquid fluorine, it is resistant to all other chemicals. It is used in various occasions that need to resist acid and alkali and organic solvents. It has tightness, high lubricity and non-stickiness, electrical insulation, good aging resistance, and excellent temperature resistance.

Is PTFE safe?

PTFE itself is not toxic to humans and can be used in medical and health applications. The yarn made of PTFE is pure inert, non-toxic, has extreme biological adaptability, does not cause rejection of the body, has no physiological side effects on the human body, can be sterilized by any method, and has a microporous structure so that it can be used. Artificial blood vessels for tissue regeneration, and surgical sutures for vascular, cardiac, general, and plastic surgery. Its excellent anti-microbial, antibacterial, long flex life and zero moisture regain, etc., make people continue to open up the application of fibers in this field. In recent years, PTFE yarns have also been used as abrasion-resistant materials for wear-resistant clothing.

Uses of Teflon and PTFE properties

The production of PTFE has solved many problems in chemical, petroleum, pharmaceutical, and other fields. Teflon seals, gaskets, and gaskets. Teflon seals, gaskets, and gaskets are molded from suspension polymerized polytetrafluoroethylene resin. Compared with other plastics, PTFE has the characteristics of chemical resistance, and it has been used as a sealing material. The dispersion liquid can be used as an insulating impregnating solution for various materials and an anti-corrosive coating on the surface of metal, glass, and ceramics. Different PTFE rings, PTFE gaskets, PTFE packings, etc. are widely used for sealing flanges of different anti-corrosive pipes.

Nowadays, all kinds of PTFE products have played a pivotal role in the national economic fields such as chemical industry, machinery, electronics, electrical appliances, military industry, aerospace, environmental protection, and bridges. PTFE use conditions industry chemical, petrochemical, oil refining, Chlor-alkali, acid production, phosphate fertilizer, pharmaceuticals, pesticides, chemical fiber, dyeing, cooking, gas, organic synthesis, non-ferrous smelting, steel, nuclear energy and polymer filter materials, high-purity product production (Such as ion membrane electrolysis), viscous materials transportation and operation, food and beverage processing and production departments with strict hygiene requirements.

PTFE lubricant

PTFE fiber has a very low coefficient of friction. It is made of fabric self-lubricating pads by weaving and impregnating resins such as phenolic resin and epoxy resin. During heavy-duty wear, a PTFE transfer film is formed between the inner and outer ring contact surfaces of the spherical plain bearing, thereby significantly reducing the friction coefficient between the inner and outer races of the bearing, and extending the service life of the self-lubricating spherical plain bearing. Plain bearings with PTFE fiber or fabric have the characteristics of lubrication-free, durable, and good environmental adaptability. They have been used in the industrial field of bearings with a heavy load, maintenance-free, small size, and lightweight. PTFE fiber bearings are used in food processing machinery to ensure food hygiene to a large extent and eliminate lubricant pollution.

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 PTFE, please contact us.

Oil additives

There are many different kinds of Oil additives, different function, according to the role of the additive, it can be divided into viscosity index improver, detergent, dispersant, oily agent (friction modifier), extreme pressure anti-wear agent, antioxidant, rust corrosion inhibitor, emulsifying agent and emulsifier, blood coagulation agent, suspending agent, antifoaming agent, etc. The cleaning agent, oil agent (friction improver), extreme pressure anti-wear agent, rust and corrosion resistant agents mainly protect the metal surface; Viscosity index improvers, dispersants, antioxidants, anti-emulsifiers and emulsifiers, depressants, suspension agents, anti-foam agents, etc. are used to improve the performance of base oils.

Friction Modifier

When the load between Friction pairs is small, the Friction Modifier can form a protective film on the surface of Friction pairs to prevent severe wear between metals. When the metal surface bears a large load or when the mechanical equipment runs at a fast speed, due to the local pressure is too large, the metal press welding together, the metal surface will be in direct contact, making the friction more intense, and produce a lot of heat, the anti-wear agent formed on the metal surface lubrication film will be destroyed. Therefore, a more effective additive than the anti-wear agent is needed, which is called extreme pressure additive. Extreme pressure additives can produce a layer of chemical reaction film with low shear strength on the metal surface, avoid abrasion, sintering, sticking and abrasion on the metal surface under high speed and high load or high temperature, and improve the bearing capacity of the metal to meet the lubrication requirements under harsh working conditions.

In the practical application process, the anti-wear agent and extreme pressure additives are not strictly distinguished, generally referred to as absolute pressure anti-wear agents.Traditional perfect pressure anti-wear agent according to the different elements in the main are divided into sulfur, phosphorus, chlorine and nitrogen, boron and metal (such as lead, zinc, molybdenum) compounds and multielement composite element, its representative respectively inorganic borate, organic borate ester, naphthenic acid lead, ZDDP additives, MoS2 and MoDTC, MoDTP compounds containing many kinds of active elements, etc.

In the process of friction, the additives in the active elements such as sulfur, phosphorus, chlorine is released, by physical or chemical adsorption form adsorption film on metal surface, or react with the metal surface, chemical reaction film, to separate the two metal surface, to prevent wear and tear on the surface of the metal and sintering, the effect of anti-wear and extreme pressure. For example, nitrogen-containing additives are mainly adsorbed on the surface of the friction pair to form protective film through chemical action. Borate is a semi-solid protective film with strong adhesive force developed on the friction surface. The extreme pressure anti-wear agent containing metal can produce a layer of protective film containing metal elements by displacement reaction between the surface of the friction pair and the metal of friction pair. This extreme pressure anti-wear effect has the advantage of no loss of friction pair metal, so it is called loss-free lubrication.ZDDP additives is a kind of excessive pressure, anti-wear, anti-friction, antioxidant, corrosion resistance and other excellent properties of grey type multifunctional oil additives, the thermal decomposition of mercaptan, sulfide, disulfide have extreme pressure anti-wear effect generated after polymer membrane, the longer the alkyl chain, the better the performance of anti-friction and anti-wear performance has the advantages of no replacement.

The additives containing sulfur, phosphorus, chlorine, and zinc will pollute the environment and corrode the metal during the preparation and use, which do not meet the requirements of green environmental protection. Nitrogen heterocyclic compounds, borates, and borates have not only excellent extreme pressure wear resistance but also the advantages of non-pollution of the environment and non-corrosion of metal, so they have extensive research and application value in the field of tribology.

Relatively more than the traditional extreme pressure anti-wear additive, rare earth materials, nanoparticles as a new research in recent years, more extreme pressure anti-wear agent, their poor solubility in lubricating oil, but can be used as the intense pressure anti-wear additives of lubricating grease, research shows that most of the rare earth oxides have excellent anti-friction and anti-wear properties at high temperature; The fluoride of lanthanum and cerium can effectively improve the extreme pressure and wear resistance of ester oil. Lanthanum fluoride can effectively prolong the wear life of the adhesive coating and increase the bearing capacity of grease. Thus it can be seen that rare earth materials have development space in the field of tribology.

The Nano oil additives

There are many different kinds of Nano oil additives and metal elemental, Nano non-metal main elemental (such as graphite, diamond, etc.), Nano metal compounds, Nano non-metal compound (such as graphite, graphene, PTFE, etc.), Nano rare earth compounds (LaF3, CeBO, CeO2), and magnetic nanoparticles (Fe3O4), etc. The dispersion and stability of nanoparticles in lubricating oil are the main factors limiting their application. Nano oil additives have anti-friction and anti-wear effect, many researchers think mainly because of the following: nanoparticles can and friction pair surface effect, form a protective film; It can act as a ball on the surface of friction pair and fill the pits on the surface of friction pair. Under the high load and the high heat generated by the friction process, the nanoparticles further penetrate the matrix of the friction pair to repair the damage, so that the friction surface is always in a smooth state.

Oil additives development direction

The combination of different types of additives will affect each other. When several additives are used in conjunction, we must pay attention to the effect of their combined use. In recent years, oil additives with environmental requirements and use requirements gradually improve, showing high performance, multi-function and the development trend of environment-friendly, therefore those who use narrow range, production of the single, chlorine-containing sulfur, phosphorus, and heavy metals additives will gradually be improved or replaced.

Extreme pressure anti-wear agents: heterocyclic nitrogen compounds and their derivatives, borates, rare earth compounds, nanoparticles, and ionic liquids have a broad development prospect. Ionic liquids have become a research hotspot in the field of tribology due to their excellent thermal stability, non-volatilization, and non-inflammability, a wide range of operating temperatures and designability of structure, etc.

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.

With the development of industrial technology, high speed, high performance, high automation, high efficiency, and long life required by modern equipment, it is challenging to meet the requirements of lubrication with mineral oil alone. Adding a small number of other substances to the lubricating material can improve its performance and give it new characteristics. These substances are called additives for lubricants.

Do oil additives really help?

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

Lubricant additives can be divided into engine oil cleaner additive, antioxidant and antiseptic, oily and anti-friction oil additive, antioxidant and metal deactivator, viscosity index improver, rust inhibitor, pour point depressant, Foaming agents and other groups, the following introduces the action mechanism of common lubricant additives.

1.Engine oil cleaner additive

Engine oil cleaner additives include detergents and dispersants. Mainly used in internal combustion engine oils (steam engine oil, diesel engine oil, railway diesel locomotive oil, two-stroke engine oil, and marine engine oil). Its primary function is to keep the inside of the engine clean, and to make the insoluble matter in a colloidal suspension state, so as not to further form carbon deposits, paint films or sludge. Specifically, its role can be divided into four aspects: acid neutralization, solubilization, dispersion, and washing.

1) Acid neutralization: engine oil cleaner additive generally has specific alkalinity, and some are even highly alkaline. It can neutralize the organic and inorganic acids produced by the oxidation of lubricating oil, preventing its further condensation, thus making the paint. The reduced membrane also prevents these acidic substances from corroding engine components.

2) Solubilization: engine oil cleaner additives are all surfactants, which can solubilize solid or liquid substances that are not soluble in oil in the center of micelles composed of 5-20 surfactant molecules In use, it will solubilize oxygen-containing compounds containing hydroxyl, carbonyl, and carboxyl groups, containing nitro compounds, moisture, etc. into the micelles to form colloids, prevent further oxidation and condensation, and reduce harmful deposition on engine components Formation and aggregation of objects.

3) Dispersion: It can adsorb the small solid particles such as carbon deposits and paint films that have been formed, and make it a colloidal solution dispersed in oil, preventing these substances from further condensing into massive particles and adhering to the machine, or depositing For sludge.

4) Washing effect: The paint film and carbon deposits that have been adsorbed on the surface of the component can be washed and dispersed in the oil to keep the engine and metal surfaces clean.

The structure of the engine oil cleaner additive is composed of three groups: lipophilic, polar, and hydrophilic. Due to the different structures, the performance of the detergent dispersant is different. Generally speaking, the detergency of ash additives Preferably, the dispersibility of the ashless additive is outstanding.

The typical representatives of engine oil cleaner additive are sulfonate, alkyl phenate, salicylate, succinimide, succinate, and polymer. The first three are also called ash cleaning dispersants, and the last three are called ashless cleaning dispersants.

2. Antioxidants

Antioxidants and antioxidants can inhibit the oxidation of oil products and are mainly used in industrial lubricants, internal combustion engines, and process oils. Antioxidants can be divided into two types according to their principle of action: 1) chain reaction terminator; 2) peroxide decomposition agent. Typical shielding phenolic and amine compound antioxidants are chain reaction terminators, which can form stable products (ROOH or ROOA) with peroxide groups (ROO.), Thereby preventing the oxidation reaction of hydrocarbon compounds in lubricating oils. Such as 2,6 phenol, 4,4 methylenebisphenol, α-naphthylamine, N, N-di-sec-butyl-p-phenylenediamine, and the like.

The peroxide decomposition agent can decompose the peroxide generated in the oxidation reaction of the oil so that the chain reaction cannot continue to develop and play an antioxidant role; it can cause an inorganic complex during the thermal decomposition process, and form a protective film on the metal surface. It has an anti-corrosion effect; under extreme pressure conditions, a chemical reaction occurs on the metal surface to form a vulcanized film with the load-bearing capacity to play an anti-wear impact, so it is a multi-effect additive. The main varieties of antioxidants and antiseptics are zinc dialkyl dithiophosphate (ZDDP), zinc thiophosphinoyl zinc, zinc thiophosphinobutyl octyl, and their products.

Phenol and amine antioxidants are mostly used in transformer oils, industrial lubricants, turbine oils, and hydraulic oils. The zinc dialkyl dithiophosphate and other compounds containing sulfur, phosphorus, or organic selenium are often used in handicraft lubricants, internal combustion engine oils, and process oils. But dithiophosphate-containing lubricating oil is not suitable for silver-plated toggle pin diesel locomotive and lubricating the top of the connecting rod steel sleeve of the engine. Dialkyldithiocarbamate can meet the requirements of silver-plated parts Machine use requirements.

3. Oil and extreme pressure anti-wear agent

1) An intense pressure anti-wear agent refers to an additive that can form a high melting point chemical reaction film with the metal surface under high temperature and high-pressure boundary lubrication conditions to prevent fusion, seizure, and scratching. Its function is that the products decomposed under the high temperature of friction can react with the metal to generate compounds with lower shear stress and melting point than pure metals, thereby preventing the contact surface from engaging and welding, and effectively protecting the metal surface. Extreme pressure anti-wear agent is mainly used in industrial gear oil, hydraulic oil, guide rail oil, cutting oil and other lubricants with excessive pressure requirements to improve the intense pressure anti-wear performance of oil products.

Extreme pressure anti-wear agents are generally divided into organic sulfides, phosphides, chlorides, organometallic salts, and borate type radical pressure anti-wear agents. The main varieties of radical pressure anti-wear agents are chlorinated paraffin, acid dibutyl phosphite, thiophosphoric nitrogen derivative, tricresol phosphate, isobutylene sulfide, dibenzyl disulfide, lead naphthenate, borate Wait.

2) Any additive that can make the lubricating oil increase the oil film strength, reduce the friction coefficient, improve the anti-wear ability, and reduce the friction and wear between moving parts is called an oily agent.

An oily agent is a surface-active agent with a polar group at one end of the molecule and an oil-soluble hydrocarbon group at the other end. Substances containing this extreme group have a strong affinity for metal surfaces. It can be firmly adsorbed on metal surfaces in a targeted manner, forming a protective film similar to a cushion between metals, preventing direct contact with metal surfaces. To reduce friction and wear.

Oily agents have high interfacial activity, and they produce physical or chemical adsorption on the metal surface. Physical adsorption is reversible. At low temperature and low load, physical adsorption works; under high heat and high pressure, the adsorbent will desorb and lose its effect. In addition to physical adsorption, fatty acid-based oily agents also have chemical adsorption. Metal soaps are formed on metal surfaces at lower temperatures to improve abrasion resistance.

Common oily agents are higher fatty acids (such as stearic acid, palmitic acid, oleic acid, lauric acid, palmitic acid, ricinoleic acid, etc.), fatty acid esters (such as ethyl stearate, butyl oleate, etc.), Fatty acid amines or amide compounds (such as amine stearate, N, N-di (polyethylene glycol) stearylamine, ceramide, etc.), sulfurized whale oil, sulfurized cottonseed oil, dimer acid, benzotriazole fat Amine salts, and acid phosphates. The oily agent is mainly used in industrial lubricants, hydraulic oil, guide rail oil, gear oil, etc.

4. Viscosity index improver

The viscosity index improver is also called tackifier or viscosity agent, and its yield is second only to detergent and dispersant. Viscosity index improvers are oil-soluble, chain-like polymers with molecular weights ranging from tens of thousands to millions.

Viscosity index improvers are dissolved in the lubricating oil. They exist in the form of coils at low temperatures, which has little effect on the viscosity of the lubricant. As the heat of the lubricant increases, the reels expand the effective volume increases, and the oil flows — the increased resistance results in a relatively significant increase in the viscosity of the lubricant.

As the viscosity index improver has different forms and has different effects on viscosity at different temperatures, it can increase thickness and improve viscosity-temperature performance. Therefore, the viscosity index improver is mainly used to increase the viscosity index of lubricants, improve viscosity-temperature performance, and increase viscosity. Viscosity index improver can be used to formulate thickened motor oil so that the formulated oil has excellent viscosity-temperature production, good low-temperature stability, low fuel consumption, and a specific anti-wear effect.

Viscosity index improvers are widely used in internal combustion engine oils, mainly used in the production of multi-grade gasoline and diesel engine oils, as well as hydraulic and gear oils. Universal viscosity index improvers are polyisobutylene, polymethacrylate, ethylene/propylene copolymer, styrene and diene copolymer, and polyethylene n-butyl ether.

5. Pour point depressant

After the temperature of the oil drops to a certain level, it will lose fluidity and solidity. The role of the pour point depressant is mainly to reduce the freezing point of the oil and ensure that the oil can flow at low temperatures. The oil contains wax. At low temperatures, high-melting paraffin hydrocarbons are often precipitated as needle-like or plate-like crystals, which are connected to form a bulk network structure to create a crystalline skeleton. The low-melting oil is adsorbed and surrounded, especially as a water-absorbing oil. Sponges, causing the entire fat to lose fluidity. Pour point depressant has two functions of adsorption and eutectic. Although depressants cannot prevent the precipitation of wax crystals, it can change the structure of wax.

Adsorption of the pour point depressant on the crystal surface of wax or forming a co-crystal with it, changing the shape and size of the wax crystal, preventing the wax crystals from forming a three-dimensional network structure, thereby maintaining the fluidity of the oil at low temperatures. Pour point depressants are widely used in various types of lubricating oils. Typical representatives are alkyl naphthalene, polymethacrylate, and polyalphaolefin.

6. Rust inhibitor

The role of the rust preventive agent is to form a strong adsorption film on the metal surface to inhibit the contact of oxygen and water, especially water, to the metal surface so that the metal will not rust. As rust preventive for petroleum additives, it must have sufficient adsorption to metals and solubility in oil. Therefore, rust preventives are composed of active polar groups and appropriate lipophilic groups. At present, the following types are widely used and have sound effects: sulfonates (calcium sulfonate, sodium sulfonate and barium sulfonate), carboxylic acids and their salts (dodecyl succinate, zinc naphthenate), N-oleoyl sarcosine octadecylamine salt), organic phosphates, imidazoline salts, ester-type rust inhibitors (lanolin and lanolin soap, stilbene-60 or 80, oxidized petroleum grease), Heterocyclic Compounds (benzotriazole), organic amines, etc.

Water-soluble rust inhibitors include sodium nitrite, potassium dichromate, trisodium phosphate, diammonium hydrogen phosphate, sodium benzoate, and triethanolamine. Rust inhibitors are mainly used in industrial lubricants, metal processing cooling lubricants, metal protective oils, etc.

7. Anti-emulsifier

Oil products will be contaminated by water during use, such as mechanical equipment leaks, large amounts of cooling water must be sprayed to cool processed parts, etc., all will enter a certain number of water in the oil, which requires that the oil products have a distinct water separation. It is not emulsified by water into W / O (water/oil) type emulsion. After emulsification or weak emulsification resistance of lubricating oil, it will lose fluidity (W / O type emulsifier will increase oil viscosity doubled) and loss of lubricity. It will also cause metal corrosion and wear. Industrial gear oil, steam turbine oil, hydraulic oil (such as oil containing zinc salt) are susceptible to water pollution, so these oil products have higher requirements for anti-emulsification performance.

There are many reasons for the reduced water separation or emulsification of the lubricating oil.

1) High viscosity oil will contain some polar components;

2) Various additives are added to industrial lubricating oils, especially detergent and dispersant, rust inhibitor, and extreme pressure anti-wear agents. Most of these additives are surfactants, and the anti-emulsification of the oil should be reduced after the addition.

3) The oil is oxidized during use to form easily emulsified compounds such as carboxylic acid, which makes the oil anti-emulsification worse.

Deepening the refining depth of the base oil and selecting the appropriate additives is undoubtedly a problem that should be considered first, but adding anti-emulsifiers is the primary way to improve the anti-emulsification of lubricating oils. After adding an anti-emulsifier to the oil, the oil/water interfacial tension can be changed to achieve the purpose of enhancing the anti-emulsification of the oil. Because the addition of the anti-emulsion can eliminate the obstacle of the dispersed phase droplets binding (that is, remove the protective film outside the droplets), and make the droplets easily bind together. Also, the anti-emulsifier can make the emulsification phase inversion effect, it is O/W type to O/W type, to achieve the purpose of water separation. More commonly used anti-emulsifiers are polyoxypropane type derivatives.

8. Defoaming agent

After refining the lubricating base oil, there will still be a small number of polar substances remaining. As the lubricating oil uses various additives to meet the high-performance requirements of different mechanical equipment, foaming will occur in the current lubrication system. Not only does it affect the pumping of the lubricating oil, but it also destroys the strength and stability of the oil film, causing unnecessary abrasion accidents, or making the machine unable to operate normally. Such phenomena as oil cut-off, air blocking, sintering will continue to occur.

The role of the antifoaming agent is to suppress the generation of foam, so as not to form a stable foam. It can adsorb on the foam film and create an unstable movie, thereby achieving the purpose of destroying the foam. The most commonly used antifoaming agent is methyl silicone oil antifoaming agent. It is insoluble in oil and is distributed in the oil in a highly dispersed state by means such as colloid mill. Its dosage is generally 1-100ppm. There is also a non-silicone antifoaming agent, which belongs to polyacrylate type polymer ester. Compared with silicone oil, it can effectively improve the air release of oil products.

9. Compound additives

With the improvement of oil quality grade, functional additives are gradually changing from a single agent to a compound agent. The performance of composite additives depends not only on the improvement of the quality of the single additive agent but also through the study of additive compounding rules to determine the nature of the cooperation of the additives to obtain the composite agent with the best overall performance. The use of composite additives can reduce the difficulty of formula screening, reduce the cost of lubricating oil production, and stabilize the quality of oil production. Now, the position of compound additives in lubricants is becoming more and more critical.

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.