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Dry lubricant

A dry lubricant, also known as a solid lubricant, is a material that reduces friction and wear between two sliding surfaces without relying on liquid oils or greases, often applied in forms such as powders, bonded films, or thin coatings.^[1] These lubricants are essential in environments where liquid lubricants degrade or are impractical, including high-vacuum conditions, extreme temperatures, and chemically aggressive settings.^[1] Common materials include layered solids like molybdenum disulfide (MoS₂), which exhibit low shear strength between their atomic layers, enabling easy sliding, and graphite (which requires adsorbed gases for optimal performance); soft metals such as silver or gold; and polymers like polytetrafluoroethylene (PTFE), known for its non-stick properties.^[2]^[3] Dry lubricants operate through mechanisms such as lamellar shearing, where weak interlayer bonds in materials like MoS₂ allow layers to slide over one another with minimal resistance, achieving friction coefficients as low as 0.04 in vacuum.^[1] Unlike liquid lubricants, which are limited by viscosity changes and evaporation at temperatures beyond approximately 300°C, solid lubricants maintain performance across a broader range, with MoS₂ stable up to ~1000°C in vacuum.^[3] They also provide advantages in contamination-prone applications, as they do not attract dust or degrade into sludge, and can offer corrosion protection when formulated with binders.^[2] Key types include loose powders for burnishing onto surfaces, resin-bonded films for durable coatings on bearings and gears, and advanced sputtered or ion-plated layers for precision components.^[1] Applications span aerospace mechanisms like satellite bearings and Apollo mission hardware, where vacuum compatibility is critical; industrial processes such as metal forming and cutting tools; and automotive components like brakes operating at elevated temperatures.^[1]^[3] Recent developments focus on non-toxic, biodegradable alternatives and nanocomposites to enhance wear resistance and environmental sustainability.^[4]

Overview

Definition and Principles

Dry lubricants, also known as solid lubricants, are solid or semi-solid substances applied as thin films, powders, or coatings to reduce friction and wear between two surfaces in relative motion under essentially dry conditions.^[5] These materials function by interposing a layer with low shear strength and high compressive strength between the contacting surfaces, thereby minimizing direct solid-to-solid interaction without relying on liquid viscosity for separation.^[5] The fundamental principles of dry lubrication involve mechanisms such as the formation of shear planes within the lubricant structure, which allow easy sliding under load, and the creation of adhesive transfer films that deposit onto the mating surfaces to provide ongoing protection.^[5] Many dry lubricants exhibit lamellar structures, consisting of layered crystals where weak interlayer bonds enable low-friction sliding, as exemplified briefly by graphite.^[5] These principles operate primarily in the boundary lubrication regime, where the lubricant film thickness is comparable to surface roughness, preventing full hydrodynamic separation but reducing asperity contact through a sacrificial solid layer.^[6] In contrast to wet lubricants, which form a fluid film to separate surfaces via viscosity and hydrodynamic pressure, dry lubricants do not generate such a liquid barrier and instead rely on direct adherence and shearing of the solid material to achieve friction reduction.^[5] Dry lubricants are broadly categorized into inorganic types, such as layered minerals with crystalline structures, and organic types, such as polymers that provide flexible, low-friction coatings.^[5]

History

The documented use of dry lubricants dates back to the 16th century in Europe, where graphite from England's Borrowdale region was employed for lubrication in locks and mechanical devices, often mixed with animal fats like pig tallow.^[7]^[8] Solid lubricants like molybdenite (natural MoS₂) were also used as early as the 17th century, often confused with graphite.^[9] Advancements in the 20th century included the expanded use of molybdenum disulfide (MoS₂) as a dry lubricant starting in the 1940s for high-performance applications.^[5] Following World War II, the field expanded with the commercialization of polytetrafluoroethylene (PTFE), first synthesized by DuPont in 1938 and adapted as a dry lubricant in the mid-20th century for its low-friction characteristics in industrial settings.^[10] Concurrently, boron nitride was commercialized in the 1960s, particularly for high-temperature lubrication in aerospace and manufacturing, building on earlier patents for its incorporation into greases.^[11] Recent developments as of 2025 have focused on integrating nanomaterials, such as graphene and its derivatives, into dry lubricant formulations to improve performance in microelectronics and precision devices, as detailed in reviews of carbon-based additives.^[12]^[13]^[14]

Benefits and Drawbacks

Dry lubricants offer several key advantages over traditional wet lubricants, particularly in demanding operational conditions. They enable clean operation by forming a solid film that leaves no liquid residue and does not attract dust or contaminants, making them ideal for environments requiring minimal contamination.^[15] Additionally, dry lubricants exhibit compatibility with extreme environments, including high vacuum where they exhibit negligible vapor pressure and no outgassing, preventing system contamination that can occur with liquids.^[16] Their wide temperature range, often spanning from -200°C to over 800°C for many formulations, surpasses the limitations of conventional mineral-based liquid lubricants, which typically degrade or lose viscosity outside narrower bands such as -50°C to 150°C (while synthetic liquids extend to higher ranges), and are limited by viscosity changes and evaporation at temperatures beyond approximately 300°C for many types.^[17] This thermal stability, combined with no need for circulatory systems or seals, reduces overall system weight and simplifies design, while also minimizing maintenance requirements in inaccessible or hard-to-service areas.^[18] Environmentally, dry lubricants avoid the release of volatile organic compounds associated with liquid evaporation and provide options that are non-toxic and biodegradable, contributing to lower pollution risks compared to petroleum-based alternatives.^[18] Despite these benefits, dry lubricants have notable drawbacks that limit their versatility relative to wet options. Their load-bearing capacity is generally lower, often supporting pressures up to 100,000–150,000 psi in boundary lubrication but falling short in high-load hydrodynamic regimes where liquids can distribute pressure more effectively across larger areas.^[16] Over time, the solid films experience wear, generating debris that may require periodic reapplication or removal to maintain performance, unlike self-replenishing liquid systems.^[15] Advanced dry lubricant formulations can incur higher initial costs due to specialized deposition techniques, and certain types show sensitivity to humidity, oxidation, or contaminants like water vapor, which can degrade the lubricating film and reduce endurance.^[17] In comparative terms, dry lubricants excel in cleanroom settings where their residue-free nature prevents particle accumulation, but they are less suitable for high-speed applications relying on hydrodynamic lubrication, as they lack the cooling and shear endurance of liquids under continuous operation. Typically, dry lubricants achieve coefficients of friction between 0.05 and 0.2, providing effective boundary lubrication but without the prolonged stability seen in wet systems under sustained shear.^[16] For instance, they are particularly valuable in aerospace mechanisms where liquid lubricants fail due to evaporation or freezing.^[15]

Materials

Graphite

Graphite, a form of crystalline carbon, consists of atoms arranged in a hexagonal layered lattice structure, where each layer is composed of strongly bonded carbon atoms connected by weak van der Waals forces between layers.^[19] This allotrope of carbon is sourced from natural flake deposits, typically mined from metamorphic rocks, or produced synthetically through high-temperature graphitization of hydrocarbon precursors like petroleum coke.^[20] The unique properties of graphite as a dry lubricant stem from its layered structure, which enables easy shearing of planes under shear stress, resulting in a low coefficient of friction typically ranging from 0.10 to 0.15.^[21] It exhibits excellent lubricity in air environments up to approximately 400°C, owing to adsorbed moisture or gases that facilitate interlayer sliding, and possesses high electrical conductivity due to delocalized π-electrons in its lattice.^[22]^[19] However, graphite begins to oxidize in air above 450°C, forming carbon dioxide and limiting its use in higher-temperature oxidizing conditions.^[23] For use as a dry lubricant, graphite is prepared as micronized powders with particle sizes of 1-10 μm to promote uniform film formation and effective coverage on surfaces.^[24] Industrial applications require purity levels exceeding 95% carbon content to minimize impurities that could impair performance.^[25] Variants include colloidal graphite, where fine particles are suspended in carriers like isopropanol for sprayable formulations that deposit a temporary dry film upon evaporation.^[26]

Molybdenum Disulfide

Molybdenum disulfide (MoS₂) consists of layered hexagonal crystals composed of molybdenum and sulfur atoms, where each layer features strong covalent bonds within the plane and weak van der Waals forces between the layers, enabling easy shear and low friction.^[27] This structure allows the layers to slide over one another, providing effective lubrication in dry conditions without relying on adsorbed moisture or vapors.^[28] As a dry lubricant, MoS₂ exhibits unique properties including thermal stability up to approximately 1100°C in vacuum and inert atmospheres and resistance to oxidation up to about 400°C in air.^[27]^[29] It maintains a low coefficient of friction ranging from 0.03 to 0.1 under various loads and environments.^[28] Additionally, MoS₂ supports high load capacities up to 250,000 psi, making it suitable for demanding mechanical contacts.^[27] Preparation of MoS₂ for dry lubrication typically involves producing platelet powders with particle sizes of 1-5 μm, available in technical grades with 85-98% purity or higher purified forms (over 98%) for specialized uses such as aerospace.^[27] Variants include micronized powders for finer dispersion and resin-bonded forms that enhance adhesion and durability on substrates.^[28] Due to its stability in vacuum, MoS₂ is particularly preferred for space applications.^[27]

Boron Nitride

Hexagonal boron nitride (h-BN), the predominant polymorph employed as a dry lubricant, features a layered structure composed of alternating boron and nitrogen atoms forming hexagonal rings within each plane, analogous to graphite's carbon lattice. Unlike graphite's nonpolar covalent C-C bonds, the intralayer B-N bonds in h-BN are polar covalent with significant ionic character, enhancing its chemical and thermal resilience while maintaining weak van der Waals forces between layers that facilitate interlayer sliding for lubrication.^[30]^[31] This structure imparts unique properties to h-BN, including high thermal stability up to 900°C in air, where it resists oxidation and retains lubricity, and excellent electrical insulation owing to its wide bandgap of approximately 6 eV. Its coefficient of friction typically ranges from 0.15 to 0.25, enabling low shear resistance, while its chemical inertness to most acids, bases, and solvents, combined with non-abrasive softness (Mohs hardness ~2), prevents surface damage in mating components.^[31]^[32]^[33] h-BN is synthesized via high-temperature reactions, such as the carbothermal reduction of boric acid with urea or ammonia precursors at 900–1200°C, yielding high-purity crystals. It is available commercially as powders with particle sizes from 0.5 to 50 μm for blending into composites or coatings, or as aerosol dispersions for direct surface application. Although cubic boron nitride (c-BN) exists as a variant with diamond-like hardness (Vickers ~4500 kg/mm²) for abrasive tools, h-BN's soft, lamellar form is specifically favored for lubrication due to its shearability.^[34]^[35]^[36] h-BN finds particular utility in high-heat environments, such as vacuum or inert atmospheres exceeding 2000°C, where it outperforms traditional lubricants.^[31]

Polytetrafluoroethylene

Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer composed of repeating units of the monomer tetrafluoroethylene (CF₂=CF₂), forming long-chain molecules that exhibit slipperiness as a dry lubricant due to their weak intermolecular forces and high molecular weight.^[37] This polymeric structure results in a material with an extremely low coefficient of static and dynamic friction, typically ranging from 0.05 to 0.1, making it suitable for low-load sliding applications where minimal wear is essential.^[38] PTFE demonstrates exceptional chemical inertness, resisting degradation from most acids, bases, and solvents across a broad pH range, which enhances its durability in harsh environments.^[39] Its operational temperature range spans from -200°C to 260°C, allowing use in both cryogenic and moderately elevated thermal conditions without significant loss of lubricity.^[40] However, PTFE's relative softness limits its load-bearing capacity to below 10,000 psi, restricting it to applications avoiding high compressive or shear stresses that could cause deformation or abrasion.^[41] In preparation for dry lubrication, PTFE is processed into fine powders with particle sizes typically between 0.1 and 10 μm, enabling easy dispersion and uniform application without clumping.^[42] These powders can also be formulated as aqueous dispersions for spray or dip coating methods, where the solvent evaporates to leave a thin, solid lubricating film.^[43] To address its inherent softness and improve mechanical stability, PTFE powders are often compounded with fillers such as glass fibers or bronze particles (up to 60% by weight), which enhance wear resistance and thermal conductivity while preserving low friction.^[44] Bronze-filled variants, in particular, provide better dimensional stability under moderate loads. Specialized variants include PTFE micropowders, which are irradiated or otherwise processed to achieve sub-micron to low-micron particle sizes for seamless blending into other lubricants or polymers at concentrations of 5-20%.^[45] These micropowders reduce the overall friction coefficient in composite formulations without altering viscosity significantly, making them ideal for enhancing the performance of greases or resins in low-load scenarios.^[46] PTFE is also commonly referenced in non-stick coatings, where its dry lubricity prevents adhesion in surface treatments.^[47]

Other Materials

Tungsten disulfide (WS₂) serves as a lamellar dry lubricant with a layered structure akin to molybdenum disulfide, enabling low shear between planes for effective lubrication. It exhibits a coefficient of friction around 0.03 and maintains stability in oxidizing environments up to approximately 450°C, surpassing the thermal limits of many conventional solid lubricants.^[48]^[49] Soft metals such as silver (Ag) and gold (Au) function as dry lubricants through plastic deformation under load, providing a conformal film that reduces friction via shear within the metal layers. These metals offer excellent performance in vacuum environments, where they maintain low coefficients of friction (0.1-0.3) and high load capacities up to 100,000 psi, making them suitable for aerospace bearings and precision mechanisms. However, their use is limited by cost and potential galling in non-vacuum conditions.^[50] Diamond-like carbon (DLC) consists of amorphous carbon films typically deposited via chemical vapor deposition (CVD), providing a hard, wear-resistant coating suitable for dry lubrication. These films achieve hardness values exceeding 1500 HV and demonstrate a low friction coefficient of about 0.1 under humid conditions, where moisture aids in surface passivation.^[51]^[52] Antimony trisulfide (Sb₂S₃) is a soft crystalline powder employed as a dry lubricant in moderate-load scenarios, particularly in legacy friction material formulations like those for brakes. Its lubricity stems from easy shear deformation, though it is less common in modern applications due to environmental concerns.^[53] Ceramic-based dry lubricants, such as lead oxide and calcium fluoride, are utilized for extreme high-temperature environments exceeding 1000°C, where organic or sulfide lubricants degrade. Lead oxide functions through plastic flow at elevated temperatures, while calcium fluoride provides stable lubrication via its ionic crystal structure up to 1000°C in non-oxidizing conditions.^[54] Emerging nanomaterials like graphene, carbon nanotubes, and MXenes have gained attention since the 2010s, with MXenes showing particular promise through 2025 for nano-scale dry lubrication due to their 2D structure enabling ultra-low friction (coefficients below 0.05) and enhanced wear resistance in micro- and nano-devices. These materials enable superlubricity, with ongoing research focusing on scalable deposition methods and hybrid composites.^[55]^[56]^[57]

Mechanisms and Properties

Structure-Function Relationship

Dry lubricants primarily achieve friction reduction through a lamellar structure, where layers of atoms or molecules are arranged in stacked sheets held together by weak van der Waals forces between the interlayers. While lamellar structures are common in materials like graphite and MoS₂, non-lamellar dry lubricants such as PTFE and soft metals operate through alternative mechanisms, including low intermolecular shear and plastic flow, respectively.^[58]^[2] This configuration enables easy sliding of the basal planes parallel to the contact surface, minimizing shear resistance during relative motion, as exemplified in hexagonal layered materials like graphite or MoS₂.^[58] The weak interlayer bonds, typically van der Waals interactions, allow the layers to shear with low energy input, directly linking the atomic-scale anisotropy to macroscopic lubricity.^[58] A key performance mechanism involves the formation of a transfer film, where lubricant particles adhere to the substrate surface, creating a thin, low-shear-strength interface that separates the contacting bodies.^[59] This adhesion occurs through mechanical interlocking or weak chemical bonds, resulting in a sacrificial layer that accommodates sliding without direct asperity contact.^[59] The transfer film's stability enhances overall friction reduction by maintaining a consistent low-friction boundary.^[60] Under applied load, the lamellar layers tend to align parallel to the sliding direction, optimizing the orientation for minimal resistance and promoting efficient load distribution across the weak planes.^[58] This shear-induced alignment exploits the structural anisotropy, where the low-adhesion interfaces facilitate reorientation into the most favorable configuration for lubricity.^[58] The fundamental relationship for friction reduction in these systems is captured by the shear stress equation \tau = \sigma \mu, where \tau is the shear stress, \sigma is the normal stress, and \mu is the coefficient of friction minimized by the inherent structural anisotropy of the lamellae.^[61] This anisotropy reduces \mu by promoting interlayer shear over in-plane deformation.^[61] Defects, such as exposed edge planes in the lamellar structure, can compromise performance by increasing surface reactivity and promoting abrasion if not controlled, as these sites exhibit stronger bonding and higher shear strength compared to basal planes.^[62] Controlling defect density is essential to preserve the low-friction benefits of the ideal layered arrangement.^[62]

Key Properties

Dry lubricants exhibit a coefficient of friction typically ranging from 0.02 to 0.3, depending on operating conditions such as load, speed, and environment.^[2]^[1] Their load-bearing capacity generally spans 10,000 to 500,000 psi, as measured using the Falex pin-and-vee block test method, which evaluates extreme pressure performance under compressive loads.^[63]^[65] Temperature stability for dry lubricants extends from cryogenic conditions around -250°C to oxidizing limits up to 1000°C, enabling use in extreme thermal environments without significant degradation.^[66]^[67] Chemically, dry lubricants demonstrate inertness to many corrosives, including acids, alkalis, and solvents, though some types show sensitivity to moisture, which can affect performance; wear rates are generally low, typically on the order of 10^{-6} to 10^{-4} mm³/Nm under standard conditions.^[66]^[68] Key testing standards include ASTM D2714, which assesses the durability of dry film lubricants under shear using a block-on-ring apparatus, providing benchmarks for friction and wear in calibrated conditions.^[66] These properties can vary slightly by material type, but the ranges represent general performance across dry lubricant formulations.^[1]

Applications

Mechanical and Industrial

Dry lubricants play a crucial role in mechanical and industrial applications, where they provide reliable friction reduction and wear protection in environments prone to contamination or where liquid lubricants are impractical. In general machinery and manufacturing, these solid materials, such as graphite and molybdenum disulfide (MoS₂), form thin films on surfaces to minimize metal-to-metal contact under boundary lubrication conditions, thereby enhancing operational efficiency and component longevity.^[69]^[70] In bearings and gears, dry lubricants significantly reduce wear in sleeve bearings, chains, and gear systems, particularly in dirty or dusty environments where traditional oils attract contaminants and accelerate degradation. For instance, dry film lubricants like tungsten disulfide (WS₂) applied to bearings prevent the ingress of particles, extending service life by maintaining low friction even under uni-directional loading that would otherwise squeeze out wet lubricants. In industrial chains and sprockets, graphite-based dry lubricants create a protective barrier that resists dust adhesion, reducing wear rates and allowing continuous operation without frequent maintenance. Similarly, for gears, these lubricants lower the coefficient of friction to as low as 0.05–0.25, which can achieve up to 50% reduction in wear under boundary conditions compared to unlubricated surfaces.^[71]^[72]^[73]^[74] For locks and hinges in mechanical assemblies, dry lubricants prevent sticking and corrosion by forming a non-sticky, durable film that withstands repeated cycles without attracting dirt. Graphite powders or PTFE-based dry lubes are commonly used in these components, ensuring smooth operation in hardware like door mechanisms and latches while avoiding the buildup associated with oil-based alternatives.^[75]^[76] In metal forming processes, dry lubricants serve as effective die lubricants for drawing and stamping operations, substantially reducing galling and surface defects on workpieces. These materials, often applied as thin films, enable higher drawing ratios and complex shapes by minimizing friction at the tool-workpiece interface, with studies showing improved formability in aluminum sheet metal compared to conventional oils. For example, third-generation dry film lubricants provide a stable boundary layer that prevents adhesion and galling, allowing for cleaner post-process handling and reduced tool wear.^[77]^[78]^[79] Textile machinery benefits from dry lubricants in lubricating high-speed spindles and other moving parts without contaminating fibers, maintaining cleanliness in production lines. MoS₂-based dry films, such as those used in spinning frames and travelers, reduce friction and wear while preventing fluff deposition and staining, supporting operations at variable speeds and loads up to 450°C. This approach ensures precise control and extends equipment life in environments sensitive to lubricant residues.^[80]^[81]

Aerospace and Automotive

Dry lubricants, particularly molybdenum disulfide (MoS₂), play a critical role in aerospace applications due to their compatibility with vacuum environments, where liquid lubricants would evaporate or degrade. In satellite mechanisms and rocket components, MoS₂ coatings provide low-friction lubrication for moving parts such as bearings, gears, and deployment hinges, preventing seizing under zero-gravity and extreme conditions.^[15] For instance, MoS₂ films are applied to gyroscopes in satellites to ensure precise, long-term operation without torque buildup or wear in the absence of atmospheric lubrication.^[15] NASA has utilized dry lubricants like MoS₂ since the Apollo era for seals and mechanisms exposed to wide temperature fluctuations, operating effectively from approximately -150°C to 150°C in space simulations and lunar conditions.^[15] These coatings endure harsh thermal cycling and radiation, maintaining integrity for critical seals in spacecraft that must withstand vacuum outgassing and micrometeoroid impacts. In simulated space tests, MoS₂-based dry films demonstrate endurance exceeding 10⁶ cycles, highlighting their reliability for high-cycle mechanisms like actuators and solar array drives.^[82] In automotive applications, dry lubricants such as MoS₂ are employed on engine valves, piston rings, and brake systems to address high-temperature and low-maintenance demands. On piston rings, MoS₂ coatings reduce friction and wear during high-speed reciprocating motion, improving fuel efficiency and extending component life under high engine operating temperatures.^[83] For engine valves, these films minimize galling and sticking in valvetrain assemblies, enabling reliable performance in high-load internal combustion engines.^[84] In brakes, MoS₂ serves as a solid lubricant in pad formulations, enhancing fade resistance and reducing noise by forming a stable transfer film during high-temperature braking events exceeding 500°C.^[85] As of 2025, dry lubricants are seeing increased adoption in electric vehicles for drivetrain components, including bearings and gears, to reduce wear and improve efficiency in high-torque, low-maintenance systems.^[86] Dry lubricants like MoS₂ and polytetrafluoroethylene (PTFE) are also applied to components in battery systems to protect against fretting wear and oxidation under high-voltage conditions, supporting reliable performance in power distribution modules operating up to 800 V. This adaptation supports the shift toward efficient, maintenance-free electrification in automotive powertrains.^[87]

Medical and Food Processing

In medical applications, dry lubricants such as polytetrafluoroethylene (PTFE) are employed to lubricate surgical tools, implants, and catheters, providing low-friction surfaces that minimize wear and enhance device performance while ensuring biocompatibility to prevent tissue irritation.^[88] PTFE coatings meet USP Class VI standards for medical applications through rigorous biocompatibility testing.^[89] In food processing, dry lubricants compliant with FDA regulations are used on conveyors and mixers to reduce friction and prevent equipment downtime while avoiding contamination of food products. These lubricants, often featuring PTFE dispersions, carry NSF H1 registration for incidental food contact, ensuring they are non-toxic and do not impart flavors or odors.^[90]^[91] For pharmaceutical machinery, hexagonal boron nitride (hBN) serves as a dry lubricant in pill presses and fillers, offering effective friction reduction at the die-punch interface to improve tablet ejection and powder flow without compromising product purity. hBN is chemically inert and non-toxic, enabling clean operation that avoids residue buildup or adulteration in formulations.^[92]^[93] Dry lubricants like PTFE exhibit compatibility with sterilization processes, withstanding autoclaving at 121°C without degradation, which allows repeated cycles for reusable medical devices while maintaining lubricity and integrity.^[94] Regulatory compliance is essential for these uses; for food contact, they adhere to 21 CFR 178.3570, permitting incidental exposure during processing with limits on migration to ensure safety.^[95]^[96]

Application Methods

Dispersion Methods

Dispersion methods for dry lubricants involve suspending solid lubricant particles in liquid carriers, such as solvents or water, to facilitate application onto surfaces, followed by carrier evaporation to leave a thin solid film. These techniques are particularly suited for achieving uniform deposition without the need for high temperatures or complex equipment during the initial application phase. Common carriers include volatile solvents like isopropyl alcohol (IPA) or deionized water, which ensure easy handling and rapid drying.^[97]^[98] Spraying is a widely used dispersion method, employing aerosol, air, or airless techniques to apply the suspension. In aerosol spraying, pre-packaged formulations allow for quick and convenient coverage, while air spraying uses conventional equipment with low-volatility solvents to handle dilute dispersions, ensuring consistent coating on larger surfaces. Airless spraying, often via handheld or automatic guns, involves applying successive thin coats with intermediate drying to prevent cracking and achieve films typically 1-10 μm thick. Upon evaporation of the carrier, such as alcohol, a solid lubricant residue forms, providing even distribution.^[97]^[98]^[1] Dipping entails immersing parts in a lubricant suspension, which is ideal for complex geometries or small components, as it promotes uniform wetting. The process includes controlled withdrawal rates to regulate coating thickness, followed by draining excess suspension and allowing the carrier to evaporate, often with optional heat curing at 300-400°F for enhanced adhesion. This method is effective for batch processing, yielding films around 5-20 μm depending on the immersion duration and suspension viscosity.^[99]^[98]^[1] Brushing provides a manual approach for spot treatments or localized applications, using pastes or suspensions with added binders to improve temporary adhesion during application. This technique suits irregular surfaces like rods or cables, where a brush or wipe applies the dispersion selectively, followed by air drying or low-heat curing. While less uniform than spraying or dipping, it allows precise control for maintenance scenarios.^[97]^[98]^[1] Key process parameters include carrier volatility, which influences evaporation rates and film uniformity; solids concentration in the dispersion, typically 5-25% to balance flowability and coverage; and drying times, ranging from minutes for air drying at room temperature to hours or 5-10 minutes under heat at 305-310°C. Proper agitation of the suspension prevents settling, and surface pretreatment enhances results. These parameters are adjusted based on the substrate and desired film properties.^[98]^[99]^[97] The primary advantages of dispersion methods lie in their ability to provide even coverage on large or intricate surfaces, enabling efficient application for initial material deposition in various industrial settings.^[1]^[99]

Powder Forms

Powder forms of dry lubricants involve the direct application of free-flowing solid particles, such as molybdenum disulfide (MoS₂) or graphite, onto surfaces without the use of liquid carriers or binders.^[16] These powders are typically applied through sifting or dusting to distribute them evenly over the target area, followed by tumbling for small parts or manual rubbing to ensure coverage.^[16] For larger components, tumbling in a barrel with the powder and media mixes the lubricant into the parts, promoting initial adhesion through mechanical action.^[100] A key step in powder application is burnishing, where the distributed particles are rubbed or compacted onto the surface using a cloth, brush, or mechanical tool to embed them and form a thin, glossy film.^[101] This process relies on mechanical interlocking of the particles with surface asperities rather than chemical bonding, resulting in a loose coating suitable for low- to moderate-wear scenarios.^[16] Particle size plays a critical role in film quality; finer particles around 1-5 μm enable smoother, more uniform films by filling microscopic surface irregularities, while larger sizes (e.g., 5-10 μm or more for MoS₂) provide better load-bearing capacity in high-pressure applications but may lead to coarser textures.^[102] Graphite powders, often in 200-mesh form (approximately 74 μm), follow similar principles for embedding.^[16] These powder methods are particularly useful for quick maintenance fixes, such as applying lubricant to gears for temporary friction reduction or to wires during drawing processes to prevent galling, with no curing time required as the film forms immediately upon burnishing.^[103]^[104] This simplicity makes them ideal for on-site repairs where rapid reassembly is needed.^[100] However, powder forms have notable limitations, including poor adhesion on smooth metal surfaces, where the lack of strong bonding leads to rapid wear and dislodgement under shear forces; effectiveness depends heavily on surface roughness for mechanical interlocking to hold the particles in place.^[100]^[69] The use of graphite dust as a dry powder lubricant dates back to the 19th century, when it was widely adopted during the Industrial Revolution for its slippery properties in machinery and metalworking.^[105]

Coating Techniques

Resin-bound coatings for dry lubricants involve mixing solid lubricant particles, such as molybdenum disulfide (MoS₂) or graphite, with thermosetting binders like epoxy or phenolic resins to form a durable anti-friction film.^[106]^[107] These mixtures are typically applied via spray methods to achieve uniform coverage on substrates, followed by air drying and heat curing at temperatures between 150°C and 200°C to cross-link the binder and secure the lubricant particles in place.^[108] For example, phenolic-bound MoS₂ formulations, such as Everlube 620 series, cure at around 300°F (149°C) to enhance thermal stability and bonding.^[109] Burn-in processes create bonded films by heating the applied lubricant particles to fuse them directly onto the substrate without a resin binder, forming layers typically 5-25 μm thick.^[109] In MoS₂-based systems, this involves spraying or dipping the substrate and then heating in a controlled atmosphere to promote adhesion via partial sintering, minimizing oxidation.^[109] Post-heating burnishing with a soft cloth refines the surface for optimal smoothness and adhesion.^[109] Vacuum deposition techniques, such as physical vapor deposition (PVD) and chemical vapor deposition (CVD), produce ultrathin dry lubricant films under high vacuum to ensure purity and uniformity.^[82] These methods vaporize MoS₂ or similar materials onto substrates, resulting in coatings thinner than 1 μm, often 0.2-0.5 μm, ideal for precision applications requiring minimal added thickness.^[82] PVD sputtering, for instance, deposits amorphous or crystalline MoS₂ layers in clean environments at temperatures below 200°C, providing low-friction performance in vacuum or inert conditions.^[110] Recent advances as of 2025 include nanotechnology-enhanced PVD and CVD methods for depositing nanocomposite MoS₂ films, which improve wear resistance and load capacity through nanostructured layers.^[111] To improve bonding on metal substrates, adhesion promoters like silane primers are applied prior to coating, forming covalent siloxane networks that enhance interface strength between the substrate and the lubricant film.^[112] Silanes, such as amino-functional variants, hydrolyze to create silanol groups that react with metal oxides, typically at room temperature or low heat, preventing delamination under shear.^[113] These coating techniques yield films with high durability, often withstanding 10⁵ to 10⁷ sliding cycles under moderate loads before significant wear, thereby enhancing material longevity in demanding environments.^[114]^[115]

Composites

Dry lubricants are integrated into polymer composites by embedding solid lubricant particles or fibers, typically at concentrations of 5-20% by volume, to create self-lubricating materials suitable for bearings and other sliding components. For instance, polytetrafluoroethylene (PTFE) is commonly incorporated into nylon matrices to enhance low-friction performance while maintaining structural integrity, allowing the composite to form a transfer film during operation that minimizes direct contact between mating surfaces.^[116]^[117] In metal-matrix composites, molybdenum disulfide (MoS₂) is sintered into metal alloys, such as copper-tin or aluminum bases, to produce bushings with improved wear resistance under high loads. The sintering process disperses MoS₂ particles within the matrix, enabling the release of lubricant layers during friction to reduce adhesive wear and maintain low coefficients of friction, often below 0.2 in dry conditions.^[118]^[119] Fiber-reinforced composites incorporate dry lubricants into carbon fiber matrices for aerospace applications, where components like bushings and actuators benefit from combined strength and lubrication. Additions of MoS₂ or PTFE to carbon fiber-reinforced polyimides provide shearable lubricant interfaces that prevent galling in high-temperature environments up to 300°C, supporting lightweight designs in aircraft structures.^[116]^[120] Fabrication of these composites typically involves extrusion or molding processes conducted at temperatures of 200-300°C to ensure uniform dispersion of the lubricant within the matrix without degrading the solid lubricant properties. Thermoplastic matrices like nylon are melted and mixed with lubricant powders before extrusion, while thermosets undergo compression molding under pressure to align fibers and achieve homogeneity.^[116]^[121] These composites exhibit performance advantages in sliding contacts, including reduced galling through the formation of protective lubricant films and wear rates 20-50% lower than unreinforced matrices, thereby extending component life in demanding applications.^[122]^[123]

References

[1]
[PDF] Solid Lubrication Fundamentals and Applications
Molybdenum disulfide is unsuitable as a dry lubricant in air because its reacts with oxygen and/or water vapor to form corrosive products [6.40, 6.41]. The ...
[2]
Solid Film Lubricants: A Practical Guide
Dry film lubricants are solid materials that provide low frictional resistance between surfaces when applied directly to interacting surfaces.Missing: definition | Show results with:definition
[3]
Solid Lubrication at High-Temperatures—A Review - PMC - NIH
Feb 24, 2022 · The objective of the present paper is to review the current state-of-the-art in solid-lubricating materials operating under dry wear conditions.
[4]
Engineers Develop Solid Lubricant to Replace Toxic Materials in ...
Oct 7, 2025 · Researchers have developed a new class of nontoxic, biodegradable solid lubricants that can be used to facilitate seed dispersal using ...
[5]
[PDF] Solid Lubrication Fundamentals and Applications
A solid lubricant can generally be defined as a material that provides lubrica- tion, under essentially dry conditions, to two surfaces moving relative to each.
[6]
How Do Solid Lubricants Work?
Solid lubricants act exclusively in the boundary regime. Their lubrication mechanism is based on their ability to form a thin film on the surfaces of moving ...Missing: principles transfer
[7]
(PDF) Graphite in archaeological context comparing to other black ...
used as a lubricant and in the production of foundry Graphite occurs in deposits of various gene- molds (Lis and Sylwestrzak 1986). In modern metal- sis ...
[8]
Graphite | Wat On Earth | University of Waterloo
Graphite was first discovered in Cumbria in North England at the beginning of the sixteenth century. Although it resembled coal, it would not burn. It did, ...Missing: locks mechanisms
[9]
Tribology History - Tribonet
Many patents for lubricants were granted during this time. Lubricants included mixtures of graphite and pig tallow, as well as mixtures of olive oil and lime in ...
[10]
The Long, Strange History of Teflon, the Indestructible Product ...
Aug 20, 2024 · On April 6, 1938, a group of chemists at DuPont gathered around part of their latest experiment: a plain metal cylinder.Missing: 1950s | Show results with:1950s
[11]
Making Teflon Stick | Invention & Technology Magazine
Du Pont stepped up its efforts to market Teflon for industrial applications, promoting the use of tape and sheets for insulation in many kinds of electrical ...<|separator|>
[12]
US3196109A - Lubricating grease containing boron nitride
Boron nitride is very inert, has a very high melting and decomposition point, and will form lubricating greases having high dropping points and very long ...Missing: commercialization | Show results with:commercialization
[13]
Graphene-Based Nanomaterials as Lubricant Additives: A Review
In this review, we summarized the recent progress which has been made in graphene-based nanomaterials for lubricant additive applications, mainly focusing ...
[14]
(PDF) Carbon Nanomaterial-Based Lubricants: Review of Recent ...
This review article summarizes the progress of research on carbon nanomaterial-based lubricants witnessed in recent years. Carbon nanomaterials, such as ...
[15]
[PDF] Lubrication of Space Systems
TABLE 3.—ADVANTAGES AND DISADVANTAGES. OF USING SOLID LUBRICANTS. Advantages. Disadvantages. Negative vapor pressure (no. Endurance life dependent on operating.
[16]
[PDF] solid lubricants - NASA Technical Reports Server (NTRS)
Bonded dry-film lubricants can provide long wear-life, good abra- sion resistance, good adhesion, and good resistance to a variety of solvents. Performance of ...
[17]
[PDF] Solid Lubrication Fundamentals and Applications
In general, optical profilers have some advantages—no specimen preparation and short analysis time—but also some disadvantages. ... solid lubricants. The ...
[18]
[PDF] AN EXPERIMENTAL INVESTIGATION CHARACTERIZING THE ...
Solid lubricants offer many advantages over liquid lubricants ... Table 1.1: Advantages and Disadvantages of Solid Lubricants [61] ... Solid lubricants can be used ...
[19]
Why is Graphite Used as a Lubricant? - Jinsun Carbon
Oct 4, 2024 · Graphite is a crystalline form of carbon that is tightly packed in a hexagonal lattice structure. Each hexagonal lattice layer is composed of ...
[20]
[PDF] Graphite - USGS Publications Warehouse
Synthetic graphite is manufactured from hydrocarbon sources using high-temperature heat treatment, and it is more expensive to produce than natural graphite.
[21]
Solid Lubricants as Friction Modifiers - DeveLub
Coefficient of friction, 0.10–0.15. Color, Blue-gray to black. Electrical ... Dry-powder lubrication: The dry powder can be sprinkled onto the load-bearing ...
[22]
An In-Depth Guide to Dry Lubricants: An Efficient Solution for Friction ...
A dry lubricant, also known as a solid lubricant, is a material that reduces wear and friction between two surfaces in contact without the need for oil or ...Missing: definition | Show results with:definition
[23]
Effect of Temperature on Graphite Oxidation Behavior | Request PDF
Aug 9, 2025 · An inert atmosphere or N 2 atmosphere is essential to preventing the oxidation of graphite, which can occur in the air above 450 • C [36] .
[24]
Graphite (C) Micron Powder, Purity: 99.9%, Size: 1-5 μm
7–11 day deliveryGraphite (C) Micron Powder, Purity: 99.9%, Size: 1-5 μm. Technical Properties. Appearance, Fine Black Powder. Carbon Content, 99.9%. Primary Particle Size, 1 ...Missing: dry micronized<|separator|>
[25]
GRPM5 Graphite – Iron Powder Manufacturers and Distributors
GRPM5 is a natural graphite with more than 95% carbon content, ground to a fine powder with average particle size of about 5 micron. Applications and Benefits.Missing: preparation | Show results with:preparation
[26]
The Colloidal Graphite Lubricant - Huron Industries
Aug 23, 2021 · The beauty of colloidal graphite lubricant is that it leaves no mess, and no contamination lubricant is needed. Wet lubricants tend to dry up, ...Missing: variants | Show results with:variants
[27]
https://doi.org/10.3390/lubricants7070057
[28]
Molybdenum Disulfide (MoS 2 ) Coatings Lubrication Review
Like graphite, MoS2 has a low friction coefficient, but, unlike graphite, it does not rely on adsorbed vapors or moisture. In fact, adsorbed vapors may actually ...
[29]
Graphite and Hexagonal Boron-Nitride have the Same Interlayer ...
Apr 10, 2012 · While graphite has nonpolar homonuclear C-C intralayer bonds, h-BN presents highly polar B-N bonds resulting in different optimal stacking ...
[30]
Boron nitride as solid lubricant - SubsTech
Dec 13, 2023 · Hexagonal boron nitride retains its lubrication properties up to 5000°F (2760°C) in inert or reducing environment and up to 1600°F (870°C) in ...<|control11|><|separator|>
[31]
[PDF] based Lubrication Additives for Improved Energy Efficiency and ...
When tested in open air, the friction coefficient of h-BN is 0.2-0.3. In high-temperature manufacturing operations, h-BN exhibits excellent chemical stability ...
[32]
Boron Nitride | BN Material Properties - Accuratus
It offers very high thermal conductivity and good thermal shock resistance. ... Coefficient of Thermal Expansion. 10–6/°C (10–6/°F). 11.9. (6.6). 3.1. (1.7).
[33]
The Synthesis and Characterization of h-BN Nanosheets with High ...
Oct 15, 2021 · The reaction temperature should be controlled between 900 and 1200 °C, below which it will lead to an extremely slow reaction. Above this ...
[34]
https://pubs.acs.org/doi/10.1021/acsomega.1c03406
[35]
Hexagonal boron nitride as a tablet lubricant and a comparison with ...
Apr 2, 2008 · Cubic boron nitride (CBN) is like diamond, being hard and abrasive (Lipp et al., 1989). Hexagonal boron nitride is like graphite being soft and ...
[36]
Polytetrafluoroethylene - PubChem - NIH
Polytetrafluoroethylene is a nonflammable, tough, inert plastic used for tubing, insulation, and as a filter or coating.
[37]
PTFE for Lubricating Greases - NLGI
PTFE is extremely slippery with coefficient of friction, COF, between 0.04 (sliding friction, D1894 [3]) and 0.1. to improve resistance to water, chemicals and ...Missing: micropowders | Show results with:micropowders
[38]
Unveiling PTFE: Properties and Qualities - PBY Plastics
Jan 15, 2024 · 1. Exceptional Chemical Resistance. PTFE is highly resistant to a wide range of chemicals, including acids, bases, and solvents. This ...
[39]
Dry Film PTFE Lubricant - ITWProBrands
Reduces Friction and Wear · Thin dry film that will not attract dust or dirt · Excellent for high temperature applications up to 500°F (260°C) · Ideal for ...
[40]
Nadcap Dry Film | Solid Film Lubricant - Wolkerstorfer
PTFE works well with loads under 5,000 psi, temperature range of -400°F to +500°F, and low speeds. MoS2 works well with loads over 5,000 psi and can handle ...
[41]
Product Finder - Micro Powders, Inc.
Micronized high quality virgin PTFE that provides superior lubricity, abrasion and temperature resistance to industrial coatings and inks.Missing: dry friction coefficient range preparation dispersions fillers
[42]
PTFE Dispersions - Daikin America
Daikin PTFE Dispersions are milky-white aqueous dispersions of stabilized minute PTFE particles designed for release coatings and impregnation of media.Missing: preparation 0.1-10 μm filled bronze
[43]
Bronze-Filled PTFE - PBY Plastics
Bronze is the most popular metallic PTFE filler. Bronze is an alloy of copper and tin, so it is attacked by acids and bases.
[44]
POLYFLON PTFE micro-powder | Fluorochemicals - Daikin Chemicals
PTFE micro-powders can also be blended with fluorocarbon or silicone oils to form very high performance lubricants and greases. PTFE based greases have ...
[45]
PTFE Micropowders Add High Resistance and Lubrication ...
Mar 27, 2023 · This PTFE micropowder can be added to rubber or plastics or dispersed as a dry lubricant to improve the friction and wear of the base material.Missing: composition variants
[46]
PTFE (Polytetrafluoroethylene) - Uses, Structure & Material Properties
Jul 8, 2025 · Polytetrafluoroethylene or PTFE is the commonly used versatile, high-performance fluoropolymer. It is made up of carbon and fluorine atoms.Missing: dry variants
[47]
[PDF] conformal tungsten disulphide solid lubricant ... - OSTI.GOV
This paper describes the synthesis, structure, tribological, and torque behavior of nanocomposite (ZnF2 in WS2 matrix) solid lubricant coatings grown by atomic ...
[48]
Tungsten Disulfide (WS2) Coating per AMS 2530 / DOD-L-85645
Low Coefficient of Friction Tungsten Disulfide (WS2) achieves a dynamic coefficient of . 030 and static . 070 to .
[49]
[PDF] lubrication by diamond and diamondlike carbon coatings
As-deposited. CVD diamond film indeed has friction and wear properties similar to those of natural and synthetic diamonds in a variety of environments.
[50]
DLC coating | Diamond-Like Carbon | IHI Ionbond
Tetrabond™ Plus T-aC is a non-hydrogenated diamond like carbon (DLC) film with a micro hardness of more than 5000 HV. This coating stands out due to its low ...
[51]
[PDF] Compositions, Functions, and Testing of Friction Brake Materials ...
These materials lubricate, raise the friction, or react with oxygen to help control interfacial films. Material. Description / Comment. Reference antimony ...
[52]
[PDF] Hardness of CaF2 and BaF2 Solid Lubricants at 25 to 670 "C
Coatings containing chemically \table CaF2 arid BaF2 are known to lubricate at temperatures from about 400 to 1000 "C, but do not lubricate at lower ...
[53]
Graphene: a new emerging lubricant - ScienceDirect.com
In this review, we provide an up-to-date survey of recent tribological studies based on graphene from the nano-scale to macro-scale.Missing: post- | Show results with:post-
[54]
The challenges and benefits of using carbon nano-tubes as friction ...
Carbon nanotubes can reduce friction, wear, and fuel consumption, but challenges include dispersion, purity, and defects.
[55]
Lubrication by lamellar solids | Proceedings of the Royal Society of ...
The structure of the lamellar solids gives rise to plate-like crystallites, and a large proportion of the surface area is composed of faces with relatively low ...
[56]
A Review of Transfer Films and Their Role in Ultra-Low-Wear ... - MDPI
This paper reviews the state of the art in the solid lubricant transfer film literature and highlights recent advances in quantitative characterization thereof.
[57]
[PDF] Tribofilms in solid lubricants
Definition. Tribofilm is defined as a thin solid film generated as a consequence of sliding contact, which is adhered on its parent worn surface but has ...
[58]
[PDF] LUBRICATION, FRICTION, AND WEAR
The effects of volatilization on lubricants of wide molecular-weight range (polymeric oils or petroleum) are to (1) increase the viscosity, (2) raise the pour ...
[59]
[PDF] ABRASION BY LAMELLAR SOLID LUBRICANTS - DTIC
The imperfect lamellar structure of boron nitride is considered to be one main reason for its inability to function as an effective solid lubricant. Page 13. 11.
[60]
Falex Pin & Vee Block
Tests a wide variety of applications! Instrument is used to evaluate wear, friction, and extreme pressure properties of lubricants, coatings, and materials.Missing: 10000-500000 | Show results with:10000-500000
[61]
Solid Film Lubricants aka Dry - Acton Metal Processing Corp.
High load carrying capacities (some exceeding 250,000 psi); Prevents galvanic corrosion at the point of contact of two dissimilar metals;
[62]
None
### Summary of Key Properties of Dry/Solid Film Lubricants
[63]
Dry Film Lubricant | When & How To Use One | Dicronite
A dry lubricant, also known as a solid film lubricant, uses a dry substance or coating to reduce friction between two surfaces.Missing: principles transfer boundary
[64]
[PDF] Friction and Wear Properties of Selected Solid Lubricating Films
coefficient of friction and wear rate, which had to be less than 0.3 and on the order of 10-6 mm3/N.m or less, respectively. The ion-plated lead films met ...
[65]
Dry Lubricants | About Tribology - Tribonet
Apr 13, 2022 · Dry lubricants are solid substances that reduce friction between sliding materials without needing liquid oil. Graphite and molybdenum ...Missing: definition | Show results with:definition
[66]
Solid Lubrication with MoS2: A Review - MDPI
MoS2 is a widely used solid lubricant, especially in aerospace, due to its lamellar structure and use when liquid lubricants are not suitable.
[67]
Dry Film Lubrication - New Hampshire Ball Bearings, Inc.
... pressure (up to 90000 psi on hard substrates). Regarding wear characteristics, however, a dry film lubricant is not as predictable as a PTFE liner. NHBB dry ...Missing: limit | Show results with:limit
[68]
Bearing Lubricant | High Precision Dry Film Coating - Dicronite
Dicronite is a dry film lubricant (tungsten disulfide WS2) that has been used as a bearing lubricant in various industries and high precision applications.
[69]
GRAPHITE DRY LUBRICANT - B'laster Products
B'laster Graphite Dry Lubricant reduces wear to extend equipment life. It creates a quick drying film that provides long-lasting lubrication.Missing: colloidal variants
[70]
[PDF] Effect of solid lubricants on friction and wear behaviour of alloyed ...
MoS2 and graphite show 30 to 50% reduction in mass loss compared to other lubricants at all sliding speeds. Friction coefficient reduces with increase in.
[71]
Lock Lubricants - EasyKeys.com
4.5 13K · 6-day delivery · 14-day returnsWe recommend you clean and lubricate the cylinder and the locking mechanism regularly with a graphite lock lubricant or a light spray, such as WD-40 high- ...<|separator|>
[72]
3-IN-ONE 2.5 oz. Lock Dry Lube, Lock Lube and Penetrant 120074
Rating 4.7 (345) · Free in-store returnsSprays on easily with a thick, protective coating for outdoor and automotive hinges, gears, sprockets, latches, door tracks, pulleys, cables and guide rails.
[73]
The use of dry film lubricants in aluminum sheet metal forming
Now dry film lubricants show advantages over conventional oil lubricants because of their higher deep drawing performance, especially on complex shaped body ...
[74]
Stamping with third-generation dry-film lubricants - The Fabricator
Oct 9, 2007 · Third-generation dry lubricants offer a controllable combination of chemical structure, hydrophilic/hydrophobic balance, polarity, physical bonding, and the ...
[75]
Dry-Film Lubricant Leads to Aha Moment - MetalForming Magazine
Aug 23, 2019 · ... reduce or eliminate metal-to-metal contact and avoid galling wear. While the process does add about 10 percent to Fleet's material cost ...
[76]
MOLYKOTE® 557 Silicone Dry Film Lubricant - DuPont
For textile, paper and woodworking industries, where it can reduce wear and friction and reduce product staining from spinning frames, knives, scissors, punches ...<|control11|><|separator|>
[77]
[PDF] Lubrication solutions for textile manufacturing equipment - DuPont
• Dry lubrication that keeps machines clean, prevents fluff deposition. • Lubrication for both low and high speeds, variable loads. • Good penetration. • Water ...
[78]
Temperature‑Dependent Friction, Wear, and Life of MoS₂ Dry Film ...
Aug 1, 2025 · Reference [20] reported five tests run at room temperature that were stopped at 5 × 106 cycles while all tests run at 200 and 250 K reached the ...
[79]
Automotive Lubricants- Solid Film Lubricants - Ws2coating
We offer two major dry film lubricants for industries – Tungsten Disulfide (WS2) and Molybdenum Disulfide (MoS2). Both coatings provide excellent service in ...
[80]
Dry film lubricant coating of MoS2 for your machines
Applications where MoS2 coating is benificial on Pistons and engine components · Piston Rings · Compression Rings · Oil Control Rings · Wrist Pins (Piston Pins) ...
[81]
Adjusting function of MoS 2 on the high-speed emergency braking ...
Mar 15, 2020 · Molybdenum disulfide (MoS2) is one of the most commonly used solid lubricant in commercial brake pads. The good lubricity of MoS2 is determined ...
[82]
Tribological coatings for electric vehicle applications - Frontiers
Solid lubricant coatings like MoS2 can benefit these applications by providing easy shear to such contact interfaces to minimize energy losses due to high- ...
[83]
[PDF] Polytetrafluoroethylene (PTFE) - FDA
Mar 31, 2021 · In addition to fundamental material biocompatibility, we focused on specific devices known to be made of PTFE.Missing: tools | Show results with:tools
[84]
Food Grade Dry Film Lubricant LDTS 1 - SKF
Free 30-day returnsSKF LDTS 1 is specially developed for automatic lubrication of flat top chains conveyors in the beverage processing industry ... NSF H1 registered. Typical ...
[85]
[PDF] VICKERLUBE FG DRY PTFE SPRAY | Vickers Oils
VICKERLUBE FG DRY PTFE SPRAY is NSF H1 Registered for incidental food contact, manufactured to ISO 9001:2015 and meets the requirements of FDA 21 CFR 178.3570.
[86]
https://www.mordorintelligence.com/industry-reports/solid-dry-lubricants-market
[87]
Evaluation of hexagonal boron nitride as a new tablet lubricant
In this study, hexagonal boron nitride (HBN) was evaluated as a new lubricant for pharmaceutical tablet manufacturing. The other conventional lubricants ...Missing: dry machinery fillers
[88]
Common Autoclave Compatible Materials - Protolabs
Oct 24, 2022 · Autoclave-compatible materials include nylon, polypropylene, polycarbonate, Teflon, PEEK, silicone, 304/316 stainless steel, and 304L/316L. ...Missing: lubricants | Show results with:lubricants
[89]
PTFE Coatings for Medical Devices & Tech - RothGreaves
RothGreaves DR PTFE cured finish is biocompatible and has passed USP Plastic Class VI testing making it suitable for use in the manufacturing of medical devices ...<|control11|><|separator|>
[90]
21 CFR 178.3570 -- Lubricants with incidental food contact. - eCFR
Lubricants with incidental food contact may be safely used on machinery used for producing, manufacturing, packing, processing, preparing, treating, packaging, ...
[91]
Food Industry Dry-Film Lubricants - vanel Tech
PTFE, FDA Compliant 21 CFR 178.3570, NSF Registered H1, Lubricants. x. Food Industry Dry-Film Lubricants Estimated Delivery - 15 to 17 days. €12.53. Product ...
[92]
Dry Lubricants in Medical Devices: Four Common Myths Dispelled
a common challenge in complex, ...
[93]
[PDF] DryFilm RA Dispersions - Miller-Stephenson Chemicals
DryFilm dispersions can be applied in any of several methods, including dipping, wiping, or brushing onto a prepared surface or by spraying (air sprays, air- ...
[94]
[PDF] Solid Lubricants. - DTIC
Dry lubricants of this type usually contain lubri- cating solids (pigments) such as lead oxide, lead sulfide, calcium fluoride, gold, silver, tellurides, ...
[95]
Dry Lubricants Explained - Acme Refining
The lubricity of many solids is attributable to a lamellar structure. The lamellae orient parallel to the surface in the direction of motion and slide easily ...
[96]
Methods of Applying Solid Lubricants - Engineers Edge
(a) Burnishing: Burnishing is a rubbing process used to apply a thin film of dry powdered solid lubricant such as graphite, MoS2 , etc., to a metal surface.Missing: sifting | Show results with:sifting
[97]
[PDF] Lubrication and Failure Mechanisms of Molybdenum Disulfide Films
In moist air, metallic-colored, coalesced films of MoS2 were transformed to a black, powdery material. X-ray diffraction studies showed that this material was ...<|control11|><|separator|>
[98]
Traxit dry lubricants – innovation since 1881
Our specialized dry drawing lubricants reduce friction during wire drawing, extend tool life, and improve wire surface quality.
[99]
Dry Lubricants and Their Use in Machinery - Nanografi
Jul 30, 2021 · The structure of graphite is made up of polycyclic carbon atoms ... Graphite is rich in mechanical properties as well as applications ...
[100]
A Brief History of The Mineral Graphite - Semco Carbon
Graphite was discovered in England, at the Borrowdale deposit in the Lake District in the 16th century, where it was used to mark sheep.Missing: locks mechanisms source
[101]
Dry Film Lubricants - Coatings For Industry, Inc
Single component slurry of Teflon™ (PTFE) in a water-based phenolic binder resin. Reduces sliding friction, limits fouling and repels water up to 500oF (260oC).
[102]
https://ntrs.nasa.gov/api/citations/19790004988/downloads/19790004988.pdf
[103]
Dry Film Lubricant Coatings | MOLYKOTE® Specialty ... - DuPont
These lubricants can be used across a variety of substrates and offer different cure options, such as heat, room temperature and UV.Missing: resin- bound epoxy phenolic
[104]
[PDF] Process Specification for Dry-Film Lubricant Application - NASA
Jun 24, 2020 · This process specification establishes the engineering requirements for the use of dry- film lubricants that are applied to metallic parts used ...Missing: burn- layers
[105]
https://www.semcocarbon.com/blog/a-brief-history-of-graphite
[106]
[PDF] Silane Coupling Agents - Gelest, Inc.
Single-component liquid-cure epoxy adhesives and coatings employ dimethylbutylidene blocked amino silanes . These materials show excellent storage stability ...<|separator|>
[107]
Silanes for Adhesion Promotion - Evonik
There are two ways to use silanes to promote adhesion in paint and coating systems. Firstly, the silane can be added when formulating the coating.
[108]
[PDF] Chameleon Coatings: Adaptive Surfaces to Reduce Friction and ...
Apr 7, 2009 · MoS2 is the most commonly used intrinsic solid lubricant, and many comprehensive studies and reviews of its properties and performance have been ...
[109]
Wear life (number of sliding cycles to DFL failure) as a function of...
The values above the plots report the number of tests in which DFL did not fail after 5×10⁶ cycles and so were stopped before wear life was reached. Source ...
[110]
[PDF] Self-Lubricating Composite Materials
Fortunately, polymers are inert in most dry bearing environments. However, some hydraulic fluids and liquid lubricants are incompatible with some polymers.
[111]
(PDF) Al2O3/PTFE Composites for Marine Self-Lubricating Bearings
Aug 9, 2025 · The 50 nm Al2O3/PTFE formed a uniformly spread friction film and transfer film during the friction process, which has better friction and wear ...
[112]
Wear and mechanical properties of sintered copper–tin composites ...
Aug 10, 2025 · However it should be noted that the addition of graphite or molybdenum disulfide (MoS2) has an adverse effect on the composites' mechanical ...
[113]
(PDF) Tribology of Self-Lubricating Metal Matrix Composites
Jul 8, 2018 · In this chapter, the current state of SLMMC research is reviewed, including materials, processing methods, and tribological performance.
[114]
Tribological properties of MoS 2 and carbon fiber reinforced ...
Aug 7, 2025 · It was found that small incorporation of MoS2 was harmful to the improvement of friction and wear behaviors of carbon fiber reinforced PI ...
[115]
[PDF] Performance of PTFE-Lined Composite Journal Bearings
Self lubricating, polymer-base composite materials are used extensively in oscillating bearings for aircraft. Examples are hinge pivot bearings for control ...
[116]
Effect of the type, size and concentration of solid lubricants on the ...
Aug 10, 2025 · The addition of solid lubricants such as nano-to-micron WS 2 and MoS 2 to PEEK can help in reducing the COF to 0.4 and wear rate by~50%, which ...
[117]
Tribological Behaviour of a PEEK/MoS 2 Polymer Composite
Aug 6, 2025 · The addition of PTFE to these composites reduced both the wear rate and the coefficient of friction. The wear rate of the different ...